NI DAQmx Python API Ation Manual Nidaqmx

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NI-DAQmx Python API Documentation
Release 0.5.0

National Instruments

May 01, 2017

API Reference:

About

Features

Installation

Usage

Support / Feedback

Bugs / Feature Requests
6.1 Information to Include When Asking for Help . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

13
13

Additional Documentation

License
8.1 nidaqmx.constants . . . . . . . . . . . . .
8.2 nidaqmx.errors . . . . . . . . . . . . . . .
8.3 nidaqmx.scale . . . . . . . . . . . . . . .
8.4 nidaqmx.stream_readers . . . . . . . . . .
8.5 nidaqmx.stream_writers . . . . . . . . . .
8.6 nidaqmx.system . . . . . . . . . . . . . .
8.6.1
nidaqmx.system.collections . . . .
8.6.2
nidaqmx.system.device . . . . . .
8.6.3
nidaqmx.system.physical_channel
8.6.4
nidaqmx.system.storage . . . . .
8.6.5
nidaqmx.system.watchdog . . . .
8.7 nidaqmx.task . . . . . . . . . . . . . . . .
8.7.1
nidaqmx.task.channel . . . . . . .
8.7.2
nidaqmx.task.channel_collection .
8.7.3
nidaqmx.task.export_signals . . .
8.7.4
nidaqmx.task.in_stream . . . . . .
8.7.5
nidaqmx.task.out_stream . . . . .
8.7.6
nidaqmx.task.timing . . . . . . .
8.7.7
nidaqmx.task.triggers . . . . . . .
8.8 nidaqmx.types . . . . . . . . . . . . . . .
8.9 nidaqmx.utils . . . . . . . . . . . . . . . .

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Indices and Tables

251

Python Module Index

253

NI-DAQmx Python API Documentation, Release 0.5.0

Info
Author

Contains a Python API for interacting with NI-DAQmx. See GitHub for the latest source.
National Instruments

API Reference:

NI-DAQmx Python API Documentation, Release 0.5.0

API Reference:

CHAPTER

About

The nidaqmx package contains an API (Application Programming Interface) for interacting with the NI-DAQmx
driver. The package is implemented in Python. This package was created and is supported by NI. The package is
implemented as a complex, highly object-oriented wrapper around the NI-DAQmx C API using the ctypes Python
library.
nidaqmx 0.5 supports all versions of the NI-DAQmx driver that ships with the C API. The C API is included in any
version of the driver that supports it. The nidaqmx package does not require installation of the C header files.
Some functions in the nidaqmx package may be unavailable with earlier versions of the NI-DAQmx driver. Visit the
ni.com/downloads to upgrade your version of NI-DAQmx.
nidaqmx supports only the Windows operating system.
nidaqmx supports CPython 2.7, 3.4+, PyPy2, and PyPy3.

NI-DAQmx Python API Documentation, Release 0.5.0

Chapter 1. About

CHAPTER

Features

The following represents a non-exhaustive list of supported features for nidaqmx:
• Fully-object oriented
• Fully-featured Task class
• Fully-featured Scale class
• Fully-featured System sub-package with System, Device, PhysicalChannel, WatchdogTask, etc. classes
• NI-DAQmx Events
• NI-DAQmx Streams
• Enums support in both Python 2 and 3
• Exceptions support
• Warnings support
• Collections that emulate Python container types
• Single, dynamic read and write methods (see Usage)
• Performant, NumPy-based reader and writer classes
• Optional parameters
• Implicitly verified properties
• Context managers
The following features are not yet supported by the nidaqmx package:
• Calibration methods
• Real-time methods

NI-DAQmx Python API Documentation, Release 0.5.0

Chapter 2. Features

CHAPTER

Installation

Running nidaqmx requires NI-DAQmx or NI-DAQmx Runtime. Visit the ni.com/downloads to download the latest
version of NI-DAQmx.
nidaqmx can be installed with pip:
$ python -m pip install nidaqmx

Or easy_install from setuptools:
$ python -m easy_install nidaqmx

You also can download the project source and run:
$ python setup.py install

NI-DAQmx Python API Documentation, Release 0.5.0

Chapter 3. Installation

CHAPTER

Usage

The following is a basic example of using an nidaqmx.task.Task object. This example illustrates how the single,
dynamic nidaqmx.task.Task.read() method returns the appropriate data type.
>>> import nidaqmx
>>> with nidaqmx.Task() as task:
...
task.ai_channels.add_ai_voltage_chan("Dev1/ai0")
...
task.read()
...
-0.07476920729381246
>>> with nidaqmx.Task() as task:
...
task.ai_channels.add_ai_voltage_chan("Dev1/ai0")
...
task.read(number_of_samples_per_channel=2)
...
[0.26001373311970705, 0.37796597238117036]
>>> from nidaqmx.constants import LineGrouping
>>> with nidaqmx.Task() as task:
...
task.di_channels.add_di_chan(
...
"cDAQ2Mod4/port0/line0:1", line_grouping=LineGrouping.CHAN_PER_LINE)
...
task.read(number_of_samples_per_channel=2)
...
[[False, True], [True, True]]

A single, dynamic nidaqmx.task.Task.write() method also exists.
>>>
>>>
>>>
...
...
...
...
1
>>>
...
...

import nidaqmx
from nidaqmx.types import CtrTime
with nidaqmx.Task() as task:
task.co_channels.add_co_pulse_chan_time("Dev1/ctr0")
sample = CtrTime(high_time=0.001, low_time=0.001)
task.write(sample)

with nidaqmx.Task() as task:
task.ao_channels.add_ao_voltage_chan("Dev1/ao0")
task.write([1.1, 2.2, 3.3, 4.4, 5.5], auto_start=True)

NI-DAQmx Python API Documentation, Release 0.5.0

...
5

Consider using the nidaqmx.stream_readers and nidaqmx.stream_writers classes to increase the performance of your application, which accept pre-allocated NumPy arrays.
Following is an example of using an nidaqmx.system.System object.
>>> import nidaqmx.system
>>> system = nidaqmx.system.System.local()
>>> system.driver_version
DriverVersion(major_version=16L, minor_version=0L, update_version=0L)
>>> for device in system.devices:
...
print(device)
...
Device(name=Dev1)
Device(name=Dev2)
Device(name=cDAQ1)
>>> import collections
>>> isinstance(system.devices, collections.Sequence)
True
>>> device = system.devices['Dev1']
>>> device == nidaqmx.system.Device('Dev1')
True
>>> isinstance(device.ai_physical_chans, collections.Sequence)
True
>>> phys_chan = device.ai_physical_chans['ai0']
>>> phys_chan
PhysicalChannel(name=Dev1/ai0)
>>> phys_chan == nidaqmx.system.PhysicalChannel('Dev1/ai0')
True
>>> phys_chan.ai_term_cfgs
[, ,
˓→]
>>> from enum import Enum
>>> isinstance(phys_chan.ai_term_cfgs[0], Enum)
True

Chapter 4. Usage

CHAPTER

Support / Feedback

The nidaqmx package is supported by NI. For support for nidaqmx, open a request through the NI support portal at
ni.com.

NI-DAQmx Python API Documentation, Release 0.5.0

Chapter 5. Support / Feedback

CHAPTER

Bugs / Feature Requests

To report a bug or submit a feature request, please use the GitHub issues page.

Information to Include When Asking for Help
Please include all of the following information when opening an issue:
• Detailed steps on how to reproduce the problem and full traceback, if applicable.
• The python version used:
$ python -c "import sys; print(sys.version)"

• The versions of the nidaqmx, numpy, six and enum34 packages used:
$ python -m pip list

• The version of the NI-DAQmx driver used. Follow this KB article to determine the version of NI-DAQmx you
have installed.
• The operating system and version, for example Windows 7, CentOS 7.2, ...

NI-DAQmx Python API Documentation, Release 0.5.0

Chapter 6. Bugs / Feature Requests

CHAPTER

Additional Documentation

Refer to the NI-DAQmx Help for API-agnostic information about NI-DAQmx or measurement concepts.
NI-DAQmx Help installs only with the full version of NI-DAQmx.

NI-DAQmx Python API Documentation, Release 0.5.0

Chapter 7. Additional Documentation

CHAPTER

License

nidaqmx is licensed under an MIT-style license (see LICENSE). Other incorporated projects may be licensed under
different licenses. All licenses allow for non-commercial and commercial use.

nidaqmx.constants
class nidaqmx.constants.ACExcitWireMode
Bases: enum.Enum
FIVE_WIRE = 5
5-wire.
FOUR_WIRE = 4
4-wire.
SIX_WIRE = 6
6-wire.
class nidaqmx.constants.ADCTimingMode
Bases: enum.Enum
AUTOMATIC = 16097
Uses the most appropriate supported timing mode based on the Sample Clock Rate.
BEST_50_HZ_REJECTION = 14713
Improves 50 Hz noise rejection while decreasing noise rejection at other frequencies.
BEST_60_HZ_REJECTION = 14714
Improves 60 Hz noise rejection while decreasing noise rejection at other frequencies.
CUSTOM = 10137
Use ai_adc_custom_timing_mode to specify a custom value controlling the tradeoff between speed and
resolution.
HIGH_RESOLUTION = 10195
Increases resolution and noise rejection while decreasing conversion rate.

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HIGH_SPEED = 14712
Increases conversion rate while decreasing resolution.
class nidaqmx.constants.AOIdleOutputBehavior
Bases: enum.Enum
HIGH_IMPEDANCE = 12527
Set the channel to high-impedance, effectively disconnecting the analog output circuitry from the I/O
connector.
MAINTAIN_EXISTING_VALUE = 12528
Continue generating the current value.
ZERO_VOLTS = 12526
Generate 0 V.
class nidaqmx.constants.AOPowerUpOutputBehavior
Bases: enum.Enum
CURRENT = 10134
Current output.
HIGH_IMPEDANCE = 12527
High-impedance state.
VOLTAGE = 10322
Voltage output.
class nidaqmx.constants.AccelChargeSensitivityUnits
Bases: enum.Enum
PICO_COULOMBS_PER_G = 16099
PicoCoulombs per g.
PICO_COULOMBS_PER_INCHES_PER_SECOND_SQUARED = 16101
PicoCoulombs per in/s^2.
PICO_COULOMBS_PER_METERS_PER_SECOND_SQUARED = 16100
PicoCoulombs per m/s^2.
class nidaqmx.constants.AccelSensitivityUnits
Bases: enum.Enum
M_VOLTS_PER_G = 12509
mVolts/g.
VOLTS_PER_G = 12510
Volts/g.
class nidaqmx.constants.AccelUnits
Bases: enum.Enum
FROM_CUSTOM_SCALE = 10065
Units a custom scale specifies. If you select this value, you must specify a custom scale name.
G = 10186
1 g is approximately equal to 9.81 m/s/s.
INCHES_PER_SECOND_SQUARED = 12471
Inches per second per second.
METERS_PER_SECOND_SQUARED = 12470
Meters per second per second.

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NI-DAQmx Python API Documentation, Release 0.5.0

class nidaqmx.constants.AcquisitionType
Bases: enum.Enum
CONTINUOUS = 10123
Acquire or generate samples until you stop the task.
FINITE = 10178
Acquire or generate a finite number of samples.
HW_TIMED_SINGLE_POINT = 12522
Acquire or generate samples continuously using hardware timing without a buffer. Hardware timed single
point sample mode is supported only for the sample clock and change detection timing types.
class nidaqmx.constants.Action
Bases: enum.Enum
CANCEL = 1
Cancel
COMMIT = 0
Commit
class nidaqmx.constants.ActiveLevel
Bases: enum.Enum
ABOVE = 10093
Pause the measurement or generation while the signal is above the threshold.
BELOW = 10107
Pause the measurement or generation while the signal is below the threshold.
class nidaqmx.constants.ActiveOrInactiveEdgeSelection
Bases: enum.Enum
ACTIVE = 14617
Active edges.
INACTIVE = 14618
Inactive edges.
class nidaqmx.constants.AngleUnits
Bases: enum.Enum
DEGREES = 10146
Degrees.
FROM_CUSTOM_SCALE = 10065
Units a custom scale specifies. If you select this value, you must specify a custom scale name.
RADIANS = 10273
Radians.
TICKS = 10304
Ticks.
class nidaqmx.constants.AngularVelocityUnits
Bases: enum.Enum
DEGREES_PER_SECOND = 16082
Degrees per second.
FROM_CUSTOM_SCALE = 10065
Units a custom scale specifies. If you select this value, you must specify a custom scale name.

8.1. nidaqmx.constants

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RADIANS_PER_SECOND = 16081
Radians per second.
RPM = 16080
Revolutions per minute.
class nidaqmx.constants.AutoZeroType
Bases: enum.Enum
EVERY_SAMPLE = 10164
Perform an auto zero at every sample of the acquisition.
NONE = 10230
Do not perform an autozero.
ONCE = 10244
Perform an auto zero at the beginning of the acquisition. This auto zero task might not run if you have
used DAQmx Control Task previously in your task.
class nidaqmx.constants.BreakMode
Bases: enum.Enum
BREAK_BEFORE_MAKE = 10110
When advancing to the next entry in the scan list, disconnect all previous connections before making any
new connections.
NO_ACTION = 10227
When advancing to the next entry in the scan list, leave all previous connections intact.
class nidaqmx.constants.BridgeConfiguration
Bases: enum.Enum
FULL_BRIDGE = 10182
Sensor is a full bridge. If you set ai_excit_use_for_scaling to True, NI-DAQmx divides the measurement
by the excitation value. Many sensors scale data to native units using scaling of volts per excitation.
HALF_BRIDGE = 10187
Sensor is a half bridge. If you set ai_excit_use_for_scaling to True, NI-DAQmx divides the measurement
by the excitation value. Many sensors scale data to native units using scaling of volts per excitation.
NO_BRIDGE = 10228
Sensor is not a Wheatstone bridge.
QUARTER_BRIDGE = 10270
Sensor is a quarter bridge. If you set ai_excit_use_for_scaling to True, NI-DAQmx divides the measurement by the excitation value. Many sensors scale data to native units using scaling of volts per excitation.
class nidaqmx.constants.BridgeElectricalUnits
Bases: enum.Enum
M_VOLTS_PER_VOLT = 15897
Millivolts per volt.
VOLTS_PER_VOLT = 15896
Volts per volt.
class nidaqmx.constants.BridgePhysicalUnits
Bases: enum.Enum
BAR = 15880
Bar.

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NI-DAQmx Python API Documentation, Release 0.5.0

FOOT_POUNDS = 15884
Pound-feet.
INCH_OUNCES = 15882
Ounce-inches.
INCH_POUNDS = 15883
Pound-inches.
KILOGRAM_FORCE = 15877
kilograms-force.
NEWTONS = 15875
Newtons.
NEWTON_METERS = 15881
Newton metres.
PASCALS = 10081
Pascals.
POUNDS = 15876
Pounds.
POUNDS_PER_SQ_INCH = 15879
Pounds per square inch.
class nidaqmx.constants.BridgeShuntCalSource
Bases: enum.Enum
BUILT_IN = 10200
Use the internal shunt.
USER_PROVIDED = 10167
Use an external shunt.
class nidaqmx.constants.BridgeUnits
Bases: enum.Enum
FROM_CUSTOM_SCALE = 10065
Units a custom scale specifies. If you select this value, you must specify a custom scale name.
FROM_TEDS = 12516
Units defined by TEDS information associated with the channel.
M_VOLTS_PER_VOLT = 15897
Millivolts per volt.
VOLTS_PER_VOLTS = 15896
Volts per volt.
class nidaqmx.constants.BusType
Bases: enum.Enum
COMPACT_DAQ = 14637
CompactDAQ.
PCI = 12582
PCI.
PCIE = 13612
PCI Express.

8.1. nidaqmx.constants

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PC_CARD = 12585
PC Card/PCMCIA.
PXI = 12583
PXI.
PXIE = 14706
PXI Express.
SCC = 14707
SCC.
SCXI = 12584
SCXI.
SWITCH_BLOCK = 15870
SwitchBlock.
TCPIP = 14828
TCP/IP.
UNKNOWN = 12588
Unknown bus type.
USB = 12586
USB.
class nidaqmx.constants.CJCSource
Bases: enum.Enum
BUILT_IN = 10200
Use a cold-junction compensation channel built into the terminal block.
CONSTANT_USER_VALUE = 10116
You must specify the cold-junction temperature.
SCANNABLE_CHANNEL = 10113
Use a channel for cold-junction compensation.
class nidaqmx.constants.CalibrationMode2
Bases: enum.Enum
CHARGE = 16105
Charge
VOLTAGE = 10322
Voltage
class nidaqmx.constants.CalibrationTerminalConfig
Bases: enum.Enum
DIFF = 10106
Differential
PSEUDO_DIFF = 12529
Pseudodifferential
class nidaqmx.constants.ChannelType
Bases: enum.Enum
ANALOG_INPUT = 10100
Analog input channel.

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NI-DAQmx Python API Documentation, Release 0.5.0

ANALOG_OUTPUT = 10102
Analog output channel.
COUNTER_INPUT = 10131
Counter input channel.
COUNTER_OUTPUT = 10132
Counter output channel.
DIGITAL_INPUT = 10151
Digital input channel.
DIGITAL_OUTPUT = 10153
Digital output channel.
class nidaqmx.constants.ChargeUnits
Bases: enum.Enum
COULOMBS = 16102
Coulombs.
FROM_CUSTOM_SCALE = 10065
Units a custom scale specifies. If you select this value, you must specify a custom scale name.
PICO_COULOMBS = 16103
PicoCoulombs.
class nidaqmx.constants.ConstrainedGenMode
Bases: enum.Enum
FIXED_50_PERCENT_DUTY_CYCLE = 14711
Pulse duty cycle must be 50 percent. The frequency can change while the task runs.
FIXED_HIGH_FREQ = 14709
Pulse frequency must be above 7.63 Hz and cannot change while the task runs. In this mode, the duty
cycle has 8 bits of resolution.
FIXED_LOW_FREQ = 14710
Pulse frequency must be below 366.21 Hz and cannot change while the task runs. In this mode, the duty
cycle has 16 bits of resolution.
UNCONSTRAINED = 14708
Counter has no restrictions on pulse generation.
class nidaqmx.constants.CountDirection
Bases: enum.Enum
COUNT_DOWN = 10124
Decrement counter.
COUNT_UP = 10128
Increment counter.
EXTERNAL_SOURCE = 10326
The state of a digital line controls the count direction. Each counter has a default count direction terminal.
class nidaqmx.constants.CounterFrequencyMethod
Bases: enum.Enum
DYNAMIC_AVERAGING = 16065
Uses one counter and automatically configures the counter settings based on the range of frequencies to be
measured. During the acquisition, the counter dynamically adjusts the number of periods that are averaged
to balance measurement accuracy and latency.

8.1. nidaqmx.constants

NI-DAQmx Python API Documentation, Release 0.5.0

HIGH_FREQUENCY_2_COUNTERS = 10157
Use two counters, one of which counts pulses of the signal to measure during the specified measurement
time.
LARGE_RANGE_2_COUNTERS = 10205
Use one counter to divide the frequency of the input signal to create a lower-frequency signal that the
second counter can more easily measure.
LOW_FREQUENCY_1_COUNTER = 10105
Use one counter that uses a constant timebase to measure the input signal.
class nidaqmx.constants.Coupling
Bases: enum.Enum
AC = 10045
Remove the DC offset from the signal.
DC = 10050
Allow NI-DAQmx to measure all of the signal.
GND = 10066
Remove the signal from the measurement and measure only ground.
class nidaqmx.constants.CurrentShuntResistorLocation
Bases: enum.Enum
EXTERNAL = 10167
Use a shunt resistor external to the device. You must specify the value of the shunt resistor by using
ai_current_shunt_resistance.
INTERNAL = 10200
Use the built-in shunt resistor of the device.
LET_DRIVER_CHOOSE = -1
class nidaqmx.constants.CurrentUnits
Bases: enum.Enum
AMPS = 10342
Amperes.
FROM_CUSTOM_SCALE = 10065
Units a custom scale specifies. If you select this value, you must specify a custom scale name.
FROM_TEDS = 12516
Units defined by TEDS information associated with the channel.
class nidaqmx.constants.DataJustification
Bases: enum.Enum
LEFT = 10209
Samples occupy the higher bits of the integer.
RIGHT = 10279
Samples occupy the lower bits of the integer.
class nidaqmx.constants.DataTransferActiveTransferMode
Bases: enum.Enum
DMA = 10054
Direct Memory Access. Data transfers take place independently from the application.

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NI-DAQmx Python API Documentation, Release 0.5.0

INTERRUPT = 10204
Data transfers take place independently from the application. Using interrupts increases CPU usage because the CPU must service interrupt requests. Typically, you should use interrupts if the device is out of
DMA channels.
POLLED = 10264
Data transfers take place when you call DAQmx Read or DAQmx Write.
USB_BULK = 12590
Data transfers take place independently from the application using a USB bulk pipe.
class nidaqmx.constants.DeassertCondition
Bases: enum.Enum
ONBOARD_MEMORY_CUSTOM_THRESHOLD = 12577
Deassert the signal when the amount of space available in the onboard memory is below the value specified
with rdy_for_xfer_event_deassert_cond_custom_threshold.
ON_BOARD_MEMORY_FULL = 10236
Deassert the signal when the onboard memory fills.
ON_BOARD_MEMORY_MORE_THAN_HALF_FULL = 10237
Deassert the signal when more than half of the onboard memory of the device fills.
class nidaqmx.constants.DigitalDriveType
Bases: enum.Enum
ACTIVE_DRIVE = 12573
Drive the output pin to approximately 0 V for logic low and +3.3 V or +5 V, depending on the device, for
logic high.
OPEN_COLLECTOR = 12574
Drive the output pin to 0 V for logic low. For logic high, the output driver assumes a high-impedance state
and does not drive a voltage.
class nidaqmx.constants.DigitalPatternCondition
Bases: enum.Enum
PATTERN_DOES_NOT_MATCH = 10253
Trigger when the physical channels do not match the specified pattern.
PATTERN_MATCHES = 10254
Trigger when the physical channels match the specified pattern.
class nidaqmx.constants.DigitalWidthUnits
Bases: enum.Enum
SAMPLE_CLOCK_PERIODS = 10286
Complete periods of the Sample Clock.
SECONDS = 10364
Seconds.
TICKS = 10304
Timebase ticks.
class nidaqmx.constants.EddyCurrentProxProbeSensitivityUnits
Bases: enum.Enum
IL = 14837
Volts/mil.

8.1. nidaqmx.constants

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ILLIMETER = 14839
Volts/mMeter.
MICRON = 14840
mVolts/micron.
MIL = 14836
mVolts/mil.
MILLIMETER = 14838
mVolts/mMeter.
class nidaqmx.constants.Edge
Bases: enum.Enum
FALLING = 10171
Falling edge(s).
RISING = 10280
Rising edge(s).
class nidaqmx.constants.EncoderType
Bases: enum.Enum
TWO_PULSE_COUNTING = 10313
Two pulse counting.
X_1 = 10090
If signal A leads signal B, count the rising edges of signal A. If signal B leads signal A, count the falling
edges of signal A.
X_2 = 10091
Count the rising and falling edges of signal A.
X_4 = 10092
Count the rising and falling edges of signal A and signal B.
class nidaqmx.constants.EncoderZIndexPhase
Bases: enum.Enum
AHIGH_BHIGH = 10040
Reset the measurement when signal A and signal B are high.
AHIGH_BLOW = 10041
Reset the measurement when signal A is high and signal B is low.
ALOW_BHIGH = 10042
Reset the measurement when signal A is low and signal B high.
ALOW_BLOW = 10043
Reset the measurement when signal A and signal B are low.
class nidaqmx.constants.EveryNSamplesEventType
Bases: enum.Enum
ACQUIRED_INTO_BUFFER = 1
Acquired Into Buffer
TRANSFERRED_FROM_BUFFER = 2
Transferred From Buffer
class nidaqmx.constants.ExcitationDCorAC
Bases: enum.Enum

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USE_AC = 10045
AC excitation.
USE_DC = 10050
DC excitation.
class nidaqmx.constants.ExcitationIdleOutputBehavior
Bases: enum.Enum
MAINTAIN_EXISTING_VALUE = 12528
Continue generating the current value.
ZERO_VOLTS_OR_AMPERES = 12526
Drive excitation output to zero.
class nidaqmx.constants.ExcitationSource
Bases: enum.Enum
EXTERNAL = 10167
Use an excitation source other than the built-in excitation source of the device. If you select this value, you
must specify the amount of excitation.
INTERNAL = 10200
Use the built-in excitation source of the device. If you select this value, you must specify the amount of
excitation.
NONE = 10230
Supply no excitation to the channel.
class nidaqmx.constants.ExcitationVoltageOrCurrent
Bases: enum.Enum
USE_CURRENT = 10134
Current excitation.
USE_VOLTAGE = 10322
Voltage excitation.
class nidaqmx.constants.ExportAction
Bases: enum.Enum
INTERLOCKED = 12549
Handshake Event deasserts after the Handshake Trigger asserts, plus the amount of time specified with
hshk_event_interlocked_deassert_delay.
LEVEL = 10210
The exported Sample Clock goes high at the beginning of the sample and goes low when the last AI
Convert begins.
PULSE = 10265
Send a pulse to the terminal.
TOGGLE = 10307
Toggle the state of the terminal from low to high or from high to low.
class nidaqmx.constants.FillMode
Bases: enum.Enum
GROUP_BY_CHANNEL = 0
Group by Channel
GROUP_BY_SCAN_NUMBER = 1
Group by Scan Number

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class nidaqmx.constants.FilterResponse
Bases: enum.Enum
BUTTERWORTH = 16076
Butterworth filter response.
CONSTANT_GROUP_DELAY = 16075
Constant group delay filter response.
ELLIPTICAL = 16077
Elliptical filter response.
HARDWARE_DEFINED = 10191
Use the hardware-defined filter response.
class nidaqmx.constants.FilterType
Bases: enum.Enum
BANDPASS = 16073
Bandpass filter.
CUSTOM = 10137
Custom filter.
HIGHPASS = 16072
Highpass filter.
LOWPASS = 16071
Lowpass filter.
NOTCH = 16074
Notch filter.
class nidaqmx.constants.ForceIEPESensorSensitivityUnits
Bases: enum.Enum
M_VOLTS_PER_NEWTON = 15891
Millivolts per newton.
M_VOLTS_PER_POUND = 15892
Millivolts per pound.
class nidaqmx.constants.ForceUnits
Bases: enum.Enum
FROM_CUSTOM_SCALE = 10065
Units a custom scale specifies. If you select this value, you must specify a custom scale name.
KILOGRAM_FORCE = 15877
Kilograms-force.
NEWTONS = 15875
Newtons.
POUNDS = 15876
Pounds.
class nidaqmx.constants.FrequencyUnits
Bases: enum.Enum
FROM_CUSTOM_SCALE = 10065
Units a custom scale specifies. If you select this value, you must specify a custom scale name.

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HZ = 10373
Hertz.
TICKS = 10304
Timebase ticks.
class nidaqmx.constants.FuncGenType
Bases: enum.Enum
SAWTOOTH = 14754
Sawtooth wave.
SINE = 14751
Sine wave.
SQUARE = 14753
Square wave.
TRIANGLE = 14752
Triangle wave.
class nidaqmx.constants.GpsSignalType
Bases: enum.Enum
IRIGB = 10070
Use the IRIG-B synchronization method. The GPS receiver sends one synchronization pulse per second, as
well as information about the number of days, hours, minutes, and seconds that elapsed since the beginning
of the current year.
NONE = 10230
Do not synchronize the counter to a GPS receiver. The timestamp measurement returns the number of
seconds that elapsed since the device powered up unless you set ci_timestamp_initial_seconds.
PPS = 10080
Use the PPS synchronization method. The GPS receiver sends one synchronization pulse per second, but
does not send any timing information. The timestamp measurement returns the number of seconds that
elapsed since the device powered up unless you set ci_timestamp_initial_seconds.
class nidaqmx.constants.HandshakeStartCondition
Bases: enum.Enum
IMMEDIATE = 10198
Device is waiting for space in the FIFO (for acquisition) or waiting for samples (for generation).
WAIT_FOR_HANDSHAKE_TRIGGER_ASSERT = 12550
Device is waiting for the Handshake Trigger to assert.
WAIT_FOR_HANDSHAKE_TRIGGER_DEASSERT = 12551
Device is waiting for the Handshake Trigger to deassert.
class nidaqmx.constants.Impedance1
Bases: enum.Enum
FIFTY_OHMS = 50
50 Ohms.
ONE_M_OHM = 1000000
1 M Ohm.
SEVENTY_FIVE_OHMS = 75
75 Ohms.

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TEN_G_OHMS = 10000000000
10 G Ohm.
class nidaqmx.constants.InputCalSource
Bases: enum.Enum
GROUND = 2
Ground
LOOPBACK_0 = 0
Loopback 0 degree shift
LOOPBACK_180 = 1
Loopback 180 degree shift
class nidaqmx.constants.InputDataTransferCondition
Bases: enum.Enum
ONBOARD_MEMORY_CUSTOM_THRESHOLD = 12577
Transfer data from the device when the
ai_data_xfer_custom_threshold are in the device FIFO.

number

samples

specified

with

ON_BOARD_MEMORY_MORE_THAN_HALF_FULL = 10237
Transfer data from the device when more than half of the onboard memory of the device fills.
ON_BOARD_MEMORY_NOT_EMPTY = 10241
Transfer data from the device when there is data in the onboard memory.
WHEN_ACQUISITION_COMPLETE = 12546
Transfer data when the acquisition is complete.
class nidaqmx.constants.LVDTSensitivityUnits
Bases: enum.Enum
M_VOLTS_PER_VOLT_PER_MILLIMETER = 12506
mVolts/Volt/mMeter.
M_VOLTS_PER_VOLT_PER_MILLI_INCH = 12505
mVolts/Volt/0.001 Inch.
class nidaqmx.constants.Language
Bases: enum.Enum
CHS = 5
DEU = 2
ENG = 0
FRA = 1
JPN = 3
KOR = 4
RAW = -1
class nidaqmx.constants.LengthUnits
Bases: enum.Enum
FROM_CUSTOM_SCALE = 10065
Units a custom scale specifies. If you select this value, you must specify a custom scale name.
INCHES = 10379
Inches.

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METERS = 10219
Meters.
TICKS = 10304
Ticks.
class nidaqmx.constants.Level
Bases: enum.Enum
HIGH = 10192
Logic high.
LOW = 10214
Logic low.
NO_CHANGE = 10160
Do not change the state of the lines. On some devices, you can select this value only for entire ports.
TRISTATE = 10310
High-impedance state. You can select this state only on devices with bidirectional lines. You cannot select
this state for dedicated digital output lines. On some devices, you can select this value only for entire ports.
class nidaqmx.constants.LineGrouping
Bases: enum.Enum
CHAN_FOR_ALL_LINES = 1
One Channel For All Lines
CHAN_PER_LINE = 0
One Channel For Each Line
class nidaqmx.constants.LoggingMode
Bases: enum.Enum
LOG = 15844
Enable logging for the task. You cannot read data using DAQmx Read when using this mode. If you
require access to the data, read from the TDMS file.
LOG_AND_READ = 15842
Enable both logging and reading data for the task. You must use DAQmx Read to read samples for NIDAQmx to stream them to disk.
OFF = 10231
Disable logging for the task.
class nidaqmx.constants.LoggingOperation
Bases: enum.Enum
CREATE = 15848
Create a new TDMS file. If the file already exists, NI-DAQmx returns an error.
CREATE_OR_REPLACE = 15847
Create a new TDMS file, or replace an existing TDMS file.
OPEN = 10437
Open an existing TDMS file, and append data to that file. If the file does not exist, NI-DAQmx returns an
error.
OPEN_OR_CREATE = 15846
Open an existing TDMS file, and append data to that file. If the file does not exist, NI-DAQmx creates a
new TDMS file.

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class nidaqmx.constants.LogicFamily
Bases: enum.Enum
FIVE_V = 14619
Compatible with TTL and 5 V CMOS signals.
THREE_POINT_THREE_V = 14621
Compatible with LVTTL signals.
TWO_POINT_FIVE_V = 14620
Compatible with 2.5 V CMOS signals.
class nidaqmx.constants.LogicLvlBehavior
Bases: enum.Enum
NONE = 10230
Supply no excitation to the channel.
PULL_UP = 16064
High logic.
class nidaqmx.constants.MIOAIConvertTimebaseSource
Bases: enum.Enum
EIGHTY_M_HZ_TIMEBASE = 14636
Use the onboard 80 MHz timebase.
EIGHT_M_HZ_TIMEBASE = 16023
Use the onboard 8 MHz timebase.
MASTER_TIMEBASE = 10282
Use the same source as the Master Timebase.
ONE_HUNDRED_M_HZ_TIMEBASE = 15857
Use the onboard 100 MHz timebase.
SAMPLE_TIMEBASE = 10284
Use the same source as Sample Clock timebase.
TWENTY_M_HZ_TIMEBASE = 12537
Use the onboard 20 MHz timebase.
class nidaqmx.constants.ModulationType
Bases: enum.Enum
AM = 14756
Amplitude modulation.
FM = 14757
Frequency modulation.
NONE = 10230
No modulation.
class nidaqmx.constants.OutputDataTransferCondition
Bases: enum.Enum
ON_BOARD_MEMORY_EMPTY = 10235
Transfer data to the device only when there is no data in the onboard memory of the device.
ON_BOARD_MEMORY_HALF_FULL_OR_LESS = 10239
Transfer data to the device any time the onboard memory is less than half full.

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ON_BOARD_MEMORY_LESS_THAN_FULL = 10242
Transfer data to the device any time the onboard memory of the device is not full.
class nidaqmx.constants.OverflowBehavior
Bases: enum.Enum
GNORE_OVERRUNS = 15863
NI-DAQmx ignores Sample Clock overruns, and the task continues to run.
TOP_TASK_AND_ERROR = 15862
Stop task and return an error.
class nidaqmx.constants.OverwriteMode
Bases: enum.Enum
DO_NOT_OVERWRITE_UNREAD_SAMPLES = 10159
The acquisition stops when it encounters a sample in the buffer that you have not read.
OVERWRITE_UNREAD_SAMPLES = 10252
When an acquisition encounters unread data in the buffer, the acquisition continues and overwrites the
unread samples with new ones. You can read the new samples by setting relative_to to ReadRelativeTo.MOST_RECENT_SAMPLE and setting offset to the appropriate number of samples.
class nidaqmx.constants.PathCapability
Bases: enum.Enum
CHANNEL_IN_USE = 10434
CHANNEL_RESERVED_FOR_ROUTING = 10436
CHANNEL_SOURCE_CONFLICT = 10435
PATH_ALREADY_EXISTS = 10432
PATH_AVAILABLE = 10431
PATH_UNSUPPORTED = 10433
class nidaqmx.constants.Polarity
Bases: enum.Enum
ACTIVE_HIGH = 10095
High state is the active state.
ACTIVE_LOW = 10096
Low state is the active state.
class nidaqmx.constants.PowerUpChannelType
Bases: enum.Enum
CHANNEL_CURRENT = 1
Current Channel
CHANNEL_HIGH_IMPEDANCE = 2
High-Impedance Channel
CHANNEL_VOLTAGE = 0
Voltage Channel
class nidaqmx.constants.PowerUpStates
Bases: enum.Enum
HIGH = 10192
Logic high.

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LOW = 10214
Logic low.
TRISTATE = 10310
High-impedance state. You can select this state only on devices with bidirectional lines. You cannot select
this state for dedicated digital output lines. On some devices, you can select this value only for entire ports.
class nidaqmx.constants.PressureUnits
Bases: enum.Enum
BAR = 15880
Bar.
FROM_CUSTOM_SCALE = 10065
Units a custom scale specifies. If you select this value, you must specify a custom scale name.
PASCALS = 10081
Pascals.
POUNDS_PER_SQ_INCH = 15879
Pounds per square inch.
class nidaqmx.constants.ProductCategory
Bases: enum.Enum
AO_SERIES = 14647
AO Series.
B_SERIES_DAQ = 14662
B Series DAQ.
COMPACT_DAQ_CHASSIS = 14658
CompactDAQ chassis.
C_SERIES_MODULE = 14659
C Series I/O module.
DIGITAL_IO = 14648
Digital I/O.
DSA = 14649
Dynamic Signal Acquisition.
E_SERIES_DAQ = 14642
E Series DAQ.
M_SERIES_DAQ = 14643
M Series DAQ.
NETWORK_DAQ = 14829
Network DAQ.
NIELVIS = 14755
NI ELVIS.
SCC_CONNECTOR_BLOCK = 14704
SCC Connector Block.
SCC_MODULE = 14705
SCC Module.
SCXI_MODULE = 14660
SCXI module.

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SC_EXPRESS = 15886
SC Express.
SC_SERIES_DAQ = 14645
SC Series DAQ.
SWITCHES = 14650
Switches.
S_SERIES_DAQ = 14644
S Series DAQ.
TIO_SERIES = 14661
TIO Series.
UNKNOWN = 12588
Unknown category.
USBDAQ = 14646
USB DAQ.
X_SERIES_DAQ = 15858
X Series DAQ.
class nidaqmx.constants.RTDType
Bases: enum.Enum
CUSTOM = 10137
You must use ai_rtd_a, ai_rtd_b, and ai_rtd_c to supply the coefficients for the Callendar-Van Dusen
equation.
PT_3750 = 12481
Pt3750.
PT_3851 = 10071
Pt3851.
PT_3911 = 12482
Pt3911.
PT_3916 = 10069
Pt3916.
PT_3920 = 10053
Pt3920.
PT_3928 = 12483
Pt3928.
class nidaqmx.constants.RVDTSensitivityUnits
Bases: enum.Enum
M_VPER_VPER_DEGREE = 12507
mVolts/Volt/Degree.
M_VPER_VPER_RADIAN = 12508
mVolts/Volt/Radian.
class nidaqmx.constants.RawDataCompressionType
Bases: enum.Enum
LOSSLESS_PACKING = 12555
Remove unused bits from samples. No resolution is lost.

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LOSSY_LSB_REMOVAL = 12556
Remove unused bits from samples. Then, if necessary, remove bits from samples until the samples are the
size specified with ai_lossy_lsb_removal_compressed_samp_size. This compression type limits resolution to the specified sample size.
NONE = 10230
Do not compress samples.
class nidaqmx.constants.ReadRelativeTo
Bases: enum.Enum
CURRENT_READ_POSITION = 10425
Start reading samples relative to the last sample returned by the previous read. For the first read operation,
this position is the first sample acquired or the first pretrigger sample if you configured a reference trigger
for the task.
FIRST_PRETRIGGER_SAMPLE = 10427
Start reading samples relative to the first pretrigger sample. You specify the number of pretrigger samples
to acquire when you configure a reference trigger.
FIRST_SAMPLE = 10424
Start reading samples relative to the first sample acquired.
MOST_RECENT_SAMPLE = 10428
Start reading samples relative to the next sample acquired. For example, use this value and set offset to -1
to read the last sample acquired.
REFERENCE_TRIGGER = 10426
Start reading samples relative to the first sample after the reference trigger occurred.
class nidaqmx.constants.RegenerationMode
Bases: enum.Enum
ALLOW_REGENERATION = 10097
Allow NI-DAQmx to regenerate samples that the device previously generated. When you choose this value,
the write marker returns to the beginning of the buffer after the device generates all samples currently in
the buffer.
DONT_ALLOW_REGENERATION = 10158
Do not allow NI-DAQmx to regenerate samples the device previously generated. When you choose this
value, NI-DAQmx waits for you to write more samples to the buffer or until the timeout expires.
class nidaqmx.constants.RelayPosition
Bases: enum.Enum
CLOSED = 10438
OPEN = 10437
class nidaqmx.constants.ResistanceConfiguration
Bases: enum.Enum
FOUR_WIRE = 4
4-wire mode.
THREE_WIRE = 3
3-wire mode.
TWO_WIRE = 2
2-wire mode.
class nidaqmx.constants.ResistanceUnits
Bases: enum.Enum

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FROM_CUSTOM_SCALE = 10065
Units a custom scale specifies. If you select this value, you must specify a custom scale name.
FROM_TEDS = 12516
Units defined by TEDS information associated with the channel.
OHMS = 10384
Ohms.
class nidaqmx.constants.ResistorState
Bases: enum.Enum
PULL_DOWN = 15951
pull down state for pull up pull down resistors
PULL_UP = 15950
pull up state for pull up/pull down resistors
class nidaqmx.constants.ResolutionType
Bases: enum.Enum
BITS = 10109
Bits.
class nidaqmx.constants.SCXI1124Range
Bases: enum.Enum
NEG_10_TO_10_V = 14634
NEG_1_TO_1_V = 14632
NEG_5_TO_5_V = 14633
ZERO_TO_FIVE_V = 14630
ZERO_TO_ONE_V = 14629
ZERO_TO_TEN_V = 14631
ZERO_TO_TWENTY_M_A = 14635
class nidaqmx.constants.SampClkOverrunBehavior
Bases: enum.Enum
REPEAT_LAST_SAMPLE = 16062
Repeat the last sample.
RETURN_SENTINEL_VALUE = 16063
Return the sentinel value.
class nidaqmx.constants.SampleInputDataWhen
Bases: enum.Enum
HANDSHAKE_TRIGGER_ASSERTS = 12552
Latch data when the Handshake Trigger asserts.
HANDSHAKE_TRIGGER_DEASSERTS = 12553
Latch data when the Handshake Trigger deasserts.
class nidaqmx.constants.SampleTimingType
Bases: enum.Enum
BURST_HANDSHAKE = 12548
Determine sample timing using burst handshaking between the device and a peripheral device.

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CHANGE_DETECTION = 12504
Acquire samples when a change occurs in the state of one or more digital input lines. The lines must be
contained within a digital input channel.
HANDSHAKE = 10389
Determine sample timing by using digital handshaking between the device and a peripheral device.
IMPLICIT = 10451
Configure only the duration of the task.
ON_DEMAND = 10390
Acquire or generate a sample on each read or write operation. This timing type is also referred to as static
or software-timed.
PIPELINED_SAMPLE_CLOCK = 14668
Device acquires or generates samples on each sample clock edge, but does not respond to certain triggers
until a few sample clock edges later. Pipelining allows higher data transfer rates at the cost of increased
trigger response latency. Refer to the device documentation for information about which triggers pipelining
affects. This timing type allows handshaking with some devices using the Pause trigger, the Ready for
Transfer event, or the Data Active event. Refer to the device documentation for more information.
SAMPLE_CLOCK = 10388
Acquire or generate samples on the specified edge of the sample clock.
class nidaqmx.constants.ScaleType
Bases: enum.Enum
LINEAR = 10447
Scale values by using the equation y=mx+b, where x is a prescaled value and y is a scaled value.
MAP_RANGES = 10448
Scale values proportionally from a range of pre-scaled values to a range of scaled values.
NONE = 10230
Do not scale electrical values to physical units.
POLYNOMIAL = 10449
Scale values by using an Nth order polynomial equation.
TABLE = 10450
Map a list of pre-scaled values to a list of corresponding scaled values, with all other values scaled proportionally.
TWO_POINT_LINEAR = 15898
You provide two pairs of electrical values and their corresponding physical values. NI-DAQmx uses those
values to calculate the slope and y-intercept of a linear equation and uses that equation to scale electrical
values to physical values.
class nidaqmx.constants.ScanRepeatMode
Bases: enum.Enum
CONTINUOUS = 10117
The task returns to the beginning of the scan list when it reaches the end of the scan list.
FINITE = 10172
The task advances through the scan list one time only. NI-DAQmx ignores any Advance Triggers after
completing the scan list.
class nidaqmx.constants.Sense
Bases: enum.Enum

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LOCAL = 16095
Local.
REMOTE = 16096
Remote.
class nidaqmx.constants.ShuntCalSelect
Bases: enum.Enum
A = 12513
Switch A.
AAND_B = 12515
Switches A and B.
B = 12514
Switch B.
class nidaqmx.constants.ShuntElementLocation
Bases: enum.Enum
NONE = 10230
R_1 = 12465
R_2 = 12466
R_3 = 12467
R_4 = 14813
class nidaqmx.constants.ShuntResistorSelect
Bases: enum.Enum
A = 12513
A
B = 12514
B
class nidaqmx.constants.Signal
Bases: enum.Enum
ADVANCE_TRIGGER = 12488
ADV_CMPLT_EVENT = 12492
AI_CONVERT_CLOCK = 12484
AI_HOLD_CMPLT_EVENT = 12493
CHANGE_DETECTION_EVENT = 12511
Timed Loop executes each time the Change Detection Event occurs.
COUNTER_OUTPUT_EVENT = 12494
Timed Loop executes each time the Counter Output Event occurs.
REFERENCE_TRIGGER = 12490
SAMPLE_CLOCK = 12487
Timed Loop executes on each active edge of the Sample Clock.
SAMPLE_COMPLETE = 12530
Timed Loop executes each time the Sample Complete Event occurs.
START_TRIGGER = 12491

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TEN_M_HZ_REF_CLOCK = 12536
TWENTY_M_HZ_TIMEBASE_CLOCK = 12486
WATCHDOG_TIMER_EXPIRED_EVENT = 12512
class nidaqmx.constants.SignalModifiers
Bases: enum.Enum
DO_NOT_INVERT_POLARITY = 0
Do not invert polarity
INVERT_POLARITY = 1
Invert polarity
class nidaqmx.constants.Slope
Bases: enum.Enum
FALLING = 10171
Trigger on the falling slope of the signal.
RISING = 10280
Trigger on the rising slope of the signal.
class nidaqmx.constants.SoftwareTrigger
Bases: enum.Enum
ADVANCE_TRIGGER = 12488
Place holder enum to make editting internal enum easier.
class nidaqmx.constants.SoundPressureUnits
Bases: enum.Enum
FROM_CUSTOM_SCALE = 10065
Units a custom scale specifies. If you select this value, you must specify a custom scale name.
PA = 10081
Pascals.
class nidaqmx.constants.SourceSelection
Bases: enum.Enum
EXTERNAL = 10167
External to the device.
INTERNAL = 10200
Internal to the device.
class nidaqmx.constants.StrainGageBridgeType
Bases: enum.Enum
FULL_BRIDGE_I = 10183
Four active gages with two pairs subjected to equal and opposite strains.
FULL_BRIDGE_II = 10184
Four active gages with two aligned with maximum principal strain and two Poisson gages in adjacent arms.
FULL_BRIDGE_III = 10185
Four active gages with two aligned with maximum principal strain and two Poisson gages in opposite arms.
HALF_BRIDGE_I = 10188
Two active gages with one aligned with maximum principal strain and one Poisson gage.
HALF_BRIDGE_II = 10189
Two active gages with equal and opposite strains.

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QUARTER_BRIDGE_I = 10271
Single active gage.
QUARTER_BRIDGE_II = 10272
Single active gage and one dummy gage.
class nidaqmx.constants.StrainGageRosetteMeasurementType
Bases: enum.Enum
CARTESIAN_SHEAR_STRAIN_XY = 15976
The tensile strain coplanar to the surface of the material under stress in the XY coordinate direction.
CARTESIAN_STRAIN_X = 15974
The tensile strain coplanar to the surface of the material under stress in the X coordinate direction.
CARTESIAN_STRAIN_Y = 15975
The tensile strain coplanar to the surface of the material under stress in the Y coordinate direction.
MAX_SHEAR_STRAIN = 15977
The maximum strain coplanar to the cross section of the material under stress.
MAX_SHEAR_STRAIN_ANGLE = 15978
The angle at which the maximum shear strain of the rosette occurs.
PRINCIPAL_STRAIN_1 = 15971
The maximum tensile strain coplanar to the surface of the material under stress.
PRINCIPAL_STRAIN_2 = 15972
The minimum tensile strain coplanar to the surface of the material under stress.
PRINCIPAL_STRAIN_ANGLE = 15973
The angle at which the principal strains of the rosette occur.
class nidaqmx.constants.StrainGageRosetteType
Bases: enum.Enum
DELTA = 15969
A delta rosette consists of three strain gages, each separated by a 60 degree angle.
RECTANGULAR = 15968
A rectangular rosette consists of three strain gages, each separated by a 45 degree angle.
TEE = 15970
A tee rosette consists of two gages oriented at 90 degrees with respect to each other.
class nidaqmx.constants.StrainUnits
Bases: enum.Enum
FROM_CUSTOM_SCALE = 10065
Units a custom scale specifies. If you select this value, you must specify a custom scale name.
STRAIN = 10299
Strain.
class nidaqmx.constants.SwitchChannelUsage
Bases: enum.Enum
LOAD_CHANNEL = 10440
You can use the channel only as the output for a signal passing through the switch.
RESERVED_FOR_ROUTING_CHANNEL = 10441
You can use the channel only to complete routes within a switch.

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SOURCE_CHANNEL = 10439
You can use the channel only as an input for a signal.
class nidaqmx.constants.SyncType
Bases: enum.Enum
MASTER = 15888
Device is the source for shared clocks and triggers.
NONE = 10230
Disables trigger skew correction.
SLAVE = 15889
Device uses clocks and triggers from the master device.
class nidaqmx.constants.TEDSUnits
Bases: enum.Enum
FROM_CUSTOM_SCALE = 10065
Units a custom scale specifies. If you select this value, you must specify a custom scale name.
FROM_TEDS = 12516
Units defined by TEDS information associated with the channel.
class nidaqmx.constants.TaskMode
Bases: enum.Enum
TASK_ABORT = 6
Abort
TASK_COMMIT = 3
Commit
TASK_RESERVE = 4
Reserve
TASK_START = 0
Start
TASK_STOP = 1
Stop
TASK_UNRESERVE = 5
Unreserve
TASK_VERIFY = 2
Verify
class nidaqmx.constants.TaskStringFormat
Bases: enum.Enum
INI = 0
JSON = 2
TAB_DELIMITED = 1
class nidaqmx.constants.TemperatureUnits
Bases: enum.Enum
DEG_C = 10143
Degrees Celsius.
DEG_F = 10144
Degrees Fahrenheit.

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DEG_R = 10145
Degrees Rankine.
FROM_CUSTOM_SCALE = 10065
Units a custom scale specifies. If you select this value, you must specify a custom scale name.
K = 10325
Kelvins.
class nidaqmx.constants.TerminalConfiguration
Bases: enum.Enum
DEFAULT = -1
Default.
DIFFERENTIAL = 10106
Differential.
NRSE = 10078
Non-Referenced Single-Ended.
PSEUDODIFFERENTIAL = 12529
Pseudodifferential.
RSE = 10083
Referenced Single-Ended.
class nidaqmx.constants.ThermocoupleType
Bases: enum.Enum
B = 10047
B-type thermocouple.
E = 10055
E-type thermocouple.
J = 10072
J-type thermocouple.
K = 10073
K-type thermocouple.
N = 10077
N-type thermocouple.
R = 10082
R-type thermocouple.
S = 10085
S-type thermocouple.
T = 10086
T-type thermocouple.
class nidaqmx.constants.TimeUnits
Bases: enum.Enum
FROM_CUSTOM_SCALE = 10065
Units a custom scale specifies. If you select this value, you must specify a custom scale name.
SECONDS = 10364
Seconds.

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TICKS = 10304
Timebase ticks.
class nidaqmx.constants.TorqueUnits
Bases: enum.Enum
FOOT_POUNDS = 15884
Pound-feet.
FROM_CUSTOM_SCALE = 10065
Units a custom scale specifies. If you select this value, you must specify a custom scale name.
INCH_OUNCES = 15882
Ounce-inches.
INCH_POUNDS = 15883
Pound-inches.
NEWTON_METERS = 15881
Newton meters.
class nidaqmx.constants.TriggerType
Bases: enum.Enum
ANALOG_EDGE = 10099
Trigger when an analog signal crosses a threshold.
ANALOG_LEVEL = 10101
Pause the measurement or generation while an analog signal is above or below a level.
ANALOG_WINDOW = 10103
Trigger when an analog signal enters or leaves a range of values.
DIGITAL_EDGE = 10150
Trigger on a rising or falling edge of a digital pulse.
DIGITAL_LEVEL = 10152
Pause the measurement or generation while a digital signal is at either a high or low state.
DIGITAL_PATTERN = 10398
Pause the measurement or generation while digital physical channels either match or do not match a digital
pattern.
INTERLOCKED = 12549
Use the Handshake Trigger as a control signal for asynchronous handshaking, such as 8255 handshaking.
NONE = 10230
Disable reference triggering for the task.
SOFTWARE = 10292
Advance to the next entry in a scan list when you call DAQmx Send Software Trigger.
class nidaqmx.constants.TriggerUsage
Bases: enum.Enum
ADVANCE = 12488
Advance trigger.
ARM_START = 14641
Arm Start trigger.
HANDSHAKE = 10389
Handshake trigger.

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PAUSE = 12489
Pause trigger.
REFERENCE = 12490
Reference trigger.
START = 12491
Start trigger.
class nidaqmx.constants.UnderflowBehavior
Bases: enum.Enum
AUSE_UNTIL_DATA_AVAILABLE = 14616
Pause the task until samples are available in the FIFO.
HALT_OUTPUT_AND_ERROR = 14615
Stop generating samples and return an error.
class nidaqmx.constants.UnitsPreScaled
Bases: enum.Enum
AMPS = 10342
Amperes.
BAR = 15880
Bar.
COULOMBS = 16102
Coulombs.
DEGREES = 10146
Degrees.
DEGREES_PER_SECOND = 16082
Degrees per second.
DEG_C = 10143
Degrees Celsius.
DEG_F = 10144
Degrees Fahrenheit.
DEG_R = 10145
Degrees Rankine.
FOOT_POUNDS = 15884
Pound-feet.
FROM_TEDS = 12516
Units defined by TEDS information associated with the channel.
G = 10186
1 g is approximately equal to 9.81 m/s/s.
HERTZ = 10373
Hertz.
INCHES = 10379
Inches.
INCHES_PER_SECOND = 15960
Inches per second.

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INCHES_PER_SECOND_SQUARED = 12471
Inches per second per second.
INCH_OUNCES = 15882
Ounce-inches.
INCH_POUNDS = 15883
Pound-inches.
K = 10325
Kelvins.
KILOGRAM_FORCE = 15877
Kilograms-force.
METERS = 10219
Meters.
METERS_PER_SECOND = 15959
Meters per second.
METERS_PER_SECOND_SQUARED = 12470
Meters per second per second.
M_VOLTS_PER_VOLT = 15897
Millivolts per volt.
NEWTONS = 15875
Newtons.
NEWTON_METERS = 15881
Newton meters.
OHMS = 10384
Ohms.
PA = 10081
Pascals.
PICO_COULOMBS = 16103
PicoCoulombs.
POUNDS = 15876
Pounds.
POUNDS_PER_SQ_INCH = 15879
Pounds per square inch.
RADIANS = 10273
Radians.
RADIANS_PER_SECOND = 16081
Radians per second.
RPM = 16080
Revolutions per minute.
SECONDS = 10364
Seconds.
STRAIN = 10299
Strain.

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TICKS = 10304
Ticks.
VOLTS = 10348
Volts.
VOLTS_PER_VOLT = 15896
Volts per volt.
class nidaqmx.constants.UsageTypeAI
Bases: enum.Enum
ACCELERATION_4_WIRE_DC_VOLTAGE = 16106
Acceleration measurement using a 4 wire DC voltage based sensor.
ACCELERATION_ACCELEROMETER_CURRENT_INPUT = 10356
Acceleration measurement using an accelerometer.
ACCELERATION_CHARGE = 16104
Acceleration measurement using a charge-based sensor.
BRIDGE = 15908
Measure voltage ratios from a Wheatstone bridge.
CHARGE = 16105
Charge measurement.
CURRENT = 10134
Current measurement.
CURRENT_ACRMS = 10351
Current RMS measurement.
FORCE_BRIDGE = 15899
Force measurement using a bridge-based sensor.
FORCE_IEPE_SENSOR = 15895
Force measurement using an IEPE Sensor.
FREQUENCY_VOLTAGE = 10181
Frequency measurement using a frequency to voltage converter.
POSITION_ANGULAR_RVDT = 10353
Position measurement using an RVDT.
POSITION_EDDY_CURRENT_PROX_PROBE = 14835
Position measurement using an eddy current proximity probe.
POSITION_LINEAR_LVDT = 10352
Position measurement using an LVDT.
PRESSURE_BRIDGE = 15902
Pressure measurement using a bridge-based sensor.
RESISTANCE = 10278
Resistance measurement.
ROSETTE_STRAIN_GAGE = 15980
Strain measurement using a rosette strain gage.
SOUND_PRESSURE_MICROPHONE = 10354
Sound pressure measurement using a microphone.

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STRAIN_STRAIN_GAGE = 10300
Strain measurement.
TEDS = 12531
Measurement type defined by TEDS.
TEMPERATURE_BUILT_IN_SENSOR = 10311
Temperature measurement using a built-in sensor on a terminal block or device. On SCXI modules, for
example, this could be the CJC sensor.
TEMPERATURE_RTD = 10301
Temperature measurement using an RTD.
TEMPERATURE_THERMISTOR = 10302
Temperature measurement using a thermistor.
TEMPERATURE_THERMOCOUPLE = 10303
Temperature measurement using a thermocouple.
TORQUE_BRIDGE = 15905
Torque measurement using a bridge-based sensor.
VELOCITY_IEPE_SENSOR = 15966
Velocity measurement using an IEPE Sensor.
VOLTAGE = 10322
Voltage measurement.
VOLTAGE_ACRMS = 10350
Voltage RMS measurement.
VOLTAGE_CUSTOM_WITH_EXCITATION = 10323
Voltage measurement with an excitation source. You can use this measurement type for custom sensors
that require excitation, but you must use a custom scale to scale the measured voltage.
class nidaqmx.constants.UsageTypeAO
Bases: enum.Enum
CURRENT = 10134
Current generation.
FUNCTION_GENERATION = 14750
Function generation.
VOLTAGE = 10322
Voltage generation.
class nidaqmx.constants.UsageTypeCI
Bases: enum.Enum
COUNT_EDGES = 10125
Count edges of a digital signal.
DUTY_CYCLE = 16070
Measure the duty cycle of a digital signal.
FREQUENCY = 10179
Measure the frequency of a digital signal.
PERIOD = 10256
Measure the period of a digital signal.
POSITION_ANGULAR_ENCODER = 10360
Angular position measurement using an angular encoder.

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POSITION_LINEAR_ENCODER = 10361
Linear position measurement using a linear encoder.
PULSE_FREQ = 15864
Pulse measurement, returning the result as frequency and duty cycle.
PULSE_TICKS = 15866
Pulse measurement, returning the result as high ticks and low ticks.
PULSE_TIME = 15865
Pulse measurement, returning the result as high time and low time.
PULSE_WIDTH_DIGITAL = 10359
Measure the width of a pulse of a digital signal.
PULSE_WIDTH_DIGITAL_SEMI_PERIOD = 10289
Measure the time between state transitions of a digital signal.
PULSE_WIDTH_DIGITAL_TWO_EDGE_SEPARATION = 10267
Measure time between edges of two digital signals.
TIME_GPS = 10362
Timestamp measurement, synchronizing the counter to a GPS receiver.
VELOCITY_ANGULAR_ENCODER = 16078
Angular velocity measurement using an angular encoder.
VELOCITY_LINEAR_ENCODER = 16079
Linear velocity measurement using a linear encoder.
class nidaqmx.constants.UsageTypeCO
Bases: enum.Enum
PULSE_FREQUENCY = 10119
Generate digital pulses defined by frequency and duty cycle.
PULSE_TICKS = 10268
Generate digital pulses defined by the number of timebase ticks that the pulse is at a low state and the
number of timebase ticks that the pulse is at a high state.
PULSE_TIME = 10269
Generate pulses defined by the time the pulse is at a low state and the time the pulse is at a high state.
class nidaqmx.constants.VelocityIEPESensorSensitivityUnits
Bases: enum.Enum
M_VOLTS_PER_INCH_PER_SECOND = 15964
Millivolts per inch per second.
M_VOLTS_PER_MILLIMETER_PER_SECOND = 15963
Millivolts per millimeter per second.
class nidaqmx.constants.VelocityUnits
Bases: enum.Enum
FROM_CUSTOM_SCALE = 10065
Units a custom scale specifies. If you select this value, you must specify a custom scale name.
INCHES_PER_SECOND = 15960
Inches per second.
METERS_PER_SECOND = 15959
Meters per second.

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class nidaqmx.constants.VoltageUnits
Bases: enum.Enum
FROM_CUSTOM_SCALE = 10065
Units a custom scale specifies. If you select this value, you must specify a custom scale name.
FROM_TEDS = 12516
Units defined by TEDS information associated with the channel.
VOLTS = 10348
Volts.
class nidaqmx.constants.WDTTaskAction
Bases: enum.Enum
CLEAR_EXPIRATION = 1
Clear Expiration
RESET_TIMER = 0
Reset Timer
class nidaqmx.constants.WaitMode
Bases: enum.Enum
POLL = 12524
Repeatedly check for available samples as fast as possible. This mode allows for the highest sampling
rates at the expense of CPU efficiency.
SLEEP = 12547
Check for available samples once per the amount of time specified in sleep_time.
WAIT_FOR_INTERRUPT = 12523
Check for available samples when the system receives an interrupt service request. This mode is the most
CPU efficient, but results in lower possible sampling rates.
YIELD = 12525
Repeatedly check for available samples, but yield control to other threads after each check. This mode
offers a balance between sampling rate and CPU efficiency.
class nidaqmx.constants.WatchdogAOExpirState
Bases: enum.Enum
CURRENT = 10134
Current output.
NO_CHANGE = 10160
Expiration does not affect the port. Do not change the state of any lines in the port, and do not lock the
port.
VOLTAGE = 10322
Voltage output.
class nidaqmx.constants.WatchdogCOExpirState
Bases: enum.Enum
HIGH = 10192
High logic.
LOW = 10214
Low logic.

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NO_CHANGE = 10160
Expiration does not affect the state of the counter output. The channels retain their states at the time of the
watchdog timer expiration, and no further counter generation runs.
class nidaqmx.constants.WaveformAttributes
Bases: enum.Enum
SAMPLES_AND_TIMING = 10140
Return the samples and timing information.
SAMPLES_ONLY = 10287
Return only samples.
SAMPLES_TIMING_AND_ATTRIBUTES = 10141
Return the samples, timing information, and other attributes, such as the name of the channel.
class nidaqmx.constants.WindowTriggerCondition1
Bases: enum.Enum
ENTERING_WINDOW = 10163
Trigger when the signal enters the window.
LEAVING_WINDOW = 10208
Trigger when the signal leaves the window.
class nidaqmx.constants.WindowTriggerCondition2
Bases: enum.Enum
INSIDE_WINDOW = 10199
Pause the measurement or generation while the trigger is inside the window.
OUTSIDE_WINDOW = 10251
Pause the measurement or generation while the signal is outside the window.
class nidaqmx.constants.WriteBasicTEDSOptions
Bases: enum.Enum
DO_NOT_WRITE = 12540
blah
WRITE_TO_EEPROM = 12538
blah
WRITE_TO_PROM = 12539
blah
class nidaqmx.constants.WriteRelativeTo
Bases: enum.Enum
CURRENT_WRITE_POSITION = 10430
Write samples relative to the current position in the buffer.
FIRST_SAMPLE = 10424
Write samples relative to the first sample.

nidaqmx.errors
exception nidaqmx.errors.DaqError(message, error_code, task_name=u’‘)
Bases: nidaqmx.errors.Error
Error raised by any DAQmx method.

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error_code
int – Specifies the NI-DAQmx error code.
error_type
nidaqmx.error_codes.DAQmxErrors – Specifies the NI-DAQmx error type.
exception nidaqmx.errors.DaqWarning(message, error_code)
Bases: exceptions.Warning
Warning raised by any NI-DAQmx method.
error_code
int – Specifies the NI-DAQmx error code.
error_type
nidaqmx.error_codes.DAQmxWarnings – Specifies the NI-DAQmx error type.
nidaqmx.errors.DaqResourceWarning
alias of _ResourceWarning

nidaqmx.scale
class nidaqmx.scale.Scale(name)
Bases: object
Represents a DAQmx scale.
__init__(name)
Parameters name (str) – Specifies the name of the scale to create.
__weakref__
list of weak references to the object (if defined)
static calculate_reverse_poly_coeff(forward_coeffs, min_val_x=-5.0, max_val_x=5.0,
num_points_to_compute=1000, reverse_poly_order=1)
Computes a set of coefficients for a polynomial that approximates the inverse of the polynomial with the
coefficients you specify with the “forward_coeffs” input. This function generates a table of x versus y
values over the range of x. This function then finds a polynomial fit, using the least squares method to
compute a polynomial that computes x when given a value for y.
Parameters
• forward_coeffs (List[float]) – Is the list of coefficients for the polynomial that
computes y given a value of x. Each element of the list corresponds to a term of the
equation.
• min_val_x (Optional[float]) – Is the minimum value of x for which you use the
polynomial. This is the smallest value of x for which the function generates a y value in
the table.
• max_val_x (Optional[float]) – Is the maximum value of x for which you use the
polynomial. This is the largest value of x for which the function generates a y value in the
table.
• num_points_to_compute (Optional[int]) – Is the number of points in the table
of x versus y values. The function spaces the values evenly between “min_val_x” and
“max_val_x”.

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• reverse_poly_order (Optional[int]) – Is the order of the reverse polynomial
to compute. For example, an input of 3 indicates a 3rd order polynomial. A value of -1
indicates a reverse polynomial of the same order as the forward polynomial.
Returns Specifies the list of coefficients for the reverse polynomial. Each element of the list
corresponds to a term of the equation. For example, if index three of the list is 9, the fourth
term of the equation is 9y^3.
Return type List[float]
static create_lin_scale(scale_name, slope, y_intercept=0.0, pre_scaled_units=, scaled_units=None)
Creates a custom scale that uses the equation y=mx+b, where x is a pre-scaled value, and y is a scaled
value. The equation is identical for input and output. If the equation is in the form x=my+b, you must first
solve for y in terms of x.
Parameters
• scale_name (str) – Specifies the name of the scale to create.
• slope (float) – Is the slope, m, in the equation.
• y_intercept (Optional[float]) – Is the y-intercept, b, in the equation.
• pre_scaled_units (Optional[nidaqmx.constants.UnitsPreScaled])
– Is the units of the values to scale.
• scaled_units (Optional[str]) – Is the units to use for the scaled value. You can
use an arbitrary string. NI-DAQmx uses the units to label a graph or chart.
Returns Indicates an object that represents the created custom scale.
Return type nidaqmx.scale.Scale
static create_map_scale(scale_name,
prescaled_min,
prescaled_max,
scaled_min,
scaled_max,
pre_scaled_units=,
scaled_units=None)
Creates a custom scale that scales values proportionally from a range of pre-scaled values to a range of
scaled values.
Parameters
• scale_name (str) – Specifies the name of the scale to create.
• prescaled_min (float) – Is the smallest value in the range of pre-scaled values.
NI-DAQmx maps this value to “scaled_min”.
• prescaled_max (float) – Is the largest value in the range of pre-scaled values. NIDAQmx maps this value to “scaled_max”.
• scaled_min (float) – Is the smallest value in the range of scaled values. NI-DAQmx
maps this value to “prescaled_min”. Read operations clip samples that are smaller than
this value. Write operations generate errors for samples that are smaller than this value.
• scaled_max (float) – Is the largest value in the range of scaled values. NI-DAQmx
maps this value to “prescaled_max”. Read operations clip samples that are larger than this
value. Write operations generate errors for samples that are larger than this value.
• pre_scaled_units (Optional[nidaqmx.constants.UnitsPreScaled])
– Is the units of the values to scale.
• scaled_units (Optional[str]) – Is the units to use for the scaled value. You can
use an arbitrary string. NI-DAQmx uses the units to label a graph or chart.
Returns Indicates an object that represents the created custom scale.
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Return type nidaqmx.scale.Scale
static create_polynomial_scale(scale_name,
forward_coeffs,
reverse_coeffs,
pre_scaled_units=,
scaled_units=None)
Creates a custom scale that uses an nth order polynomial equation. NI-DAQmx requires both a polynomial
to convert pre- scaled values to scaled values (forward) and a polynomial to convert scaled values to
pre-scaled values (reverse). If you only know one set of coefficients, use the DAQmx Compute Reverse
Polynomial Coefficients function to generate the other set.
Parameters
• scale_name (str) – Specifies the name of the scale to create.
• forward_coeffs (List[float]) – Is an list of coefficients for the polynomial that
converts pre-scaled values to scaled values. Each element of the list corresponds to a term
of the equation.
• reverse_coeffs (List[float]) – Is an list of coefficients for the polynomial that
converts scaled values to pre-scaled values. Each element of the list corresponds to a term
of the equation.
• pre_scaled_units (Optional[nidaqmx.constants.UnitsPreScaled])
– Is the units of the values to scale.
• scaled_units (Optional[str]) – Is the units to use for the scaled value. You can
use an arbitrary string. NI-DAQmx uses the units to label a graph or chart.
Returns Indicates an object that represents the created custom scale.
Return type nidaqmx.scale.Scale
static create_table_scale(scale_name,
prescaled_vals,
scaled_vals,
pre_scaled_units=,
scaled_units=None)
Creates a custom scale that maps an list of pre-scaled values to an list of corresponding scaled values.
NI-DAQmx applies linear interpolation to values that fall between the values in the table. Read operations
clip scaled samples that are outside the maximum and minimum scaled values found in the table. Write
operations generate errors for samples that are outside the minimum and maximum scaled values found in
the table.
Parameters
• scale_name (str) – Specifies the name of the scale to create.
• prescaled_vals (List[float]) – Is the list of pre-scaled values that map to the
values in “scaled_vals”.
• scaled_vals (List[float]) – Is the list of scaled values that map to the values in
“prescaled_vals”.
• pre_scaled_units (Optional[nidaqmx.constants.UnitsPreScaled])
– Is the units of the values to scale.
• scaled_units (Optional[str]) – Is the units to use for the scaled value. You can
use an arbitrary string. NI-DAQmx uses the units to label a graph or chart.
Returns Indicates an object that represents the created custom scale.
Return type nidaqmx.scale.Scale
description
str – Specifies a description for the scale.

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lin_slope
float – Specifies the slope, m, in the equation y=mx+b.
lin_y_intercept
float – Specifies the y-intercept, b, in the equation y=mx+b.
map_pre_scaled_max
float – Specifies the largest value in the range of pre-scaled values. NI-DAQmx maps this value to
map_scaled_max.
map_pre_scaled_min
float – Specifies the smallest value in the range of pre-scaled values. NI-DAQmx maps this value to
map_scaled_min.
map_scaled_max
float – Specifies the largest value in the range of scaled values. NI-DAQmx maps this value to
map_pre_scaled_max. Reads coerce samples that are larger than this value to match this value. Writes
generate errors for samples that are larger than this value.
map_scaled_min
float – Specifies the smallest value in the range of scaled values. NI-DAQmx maps this value to
map_pre_scaled_min. Reads coerce samples that are smaller than this value to match this value. Writes
generate errors for samples that are smaller than this value.
name
str – Specifies the name of this scale.
poly_forward_coeff
List[float] – Specifies a list of coefficients for the polynomial that converts pre-scaled values to scaled
values. Each element of the list corresponds to a term of the equation. For example, if index three of the
list is 9, the fourth term of the equation is 9x^3.
poly_reverse_coeff
List[float] – Specifies a list of coefficients for the polynomial that converts scaled values to pre-scaled
values. Each element of the list corresponds to a term of the equation. For example, if index three of the
list is 9, the fourth term of the equation is 9y^3.
pre_scaled_units
nidaqmx.constants.UnitsPreScaled – Specifies the units of the values that you want to scale.
save(save_as=u’‘, author=u’‘, overwrite_existing_scale=False, allow_interactive_editing=True, allow_interactive_deletion=True)
Saves this custom scale to MAX.
Parameters
• save_as (Optional[str]) – Is the name to save the task, global channel, or custom
scale as. If you do not specify a value for this input, NI-DAQmx uses the name currently
assigned to the task, global channel, or custom scale.
• author (Optional[str]) – Is a name to store with the task, global channel, or custom
scale.
• options (Optional[int]) – Specifies whether to allow the task, global channel, or
custom scale to be deleted through MAX.
• overwrite_existing_scale (Optional[bool]) – Specifies whether to overwrite a custom scale of the same name if one is already saved in MAX. If this input is
False and a custom scale of the same name is already saved in MAX, this function returns
an error.

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These values map directly to the values in ta-

nidaqmx.stream_readers
class nidaqmx.stream_readers.AnalogSingleChannelReader(task_in_stream)
Bases: nidaqmx.stream_readers.ChannelReaderBase
Reads samples from an analog input channel in an NI-DAQmx task.
read_many_sample(data, number_of_samples_per_channel=-1, timeout=10.0)
Reads one or more floating-point samples from a single analog input channel in a task.
This read method accepts a preallocated NumPy array to hold the samples requested, which can be advantageous for performance and interoperability with NumPy and SciPy.
Passing in a preallocated array is valuable in continuous acquisition scenarios, where the same array can
be used repeatedly in each call to the method.
Parameters
• data (numpy.ndarray) – Specifies a preallocated 1D NumPy array of floating-point
values to hold the samples requested.
Each element in the array corresponds to a sample from the channel. The size of the array
must be large enough to hold all requested samples from the channel in the task; otherwise,
an error is thrown.
• number_of_samples_per_channel (Optional[int]) – Specifies the number
of samples to read.
If you set this input to nidaqmx.constants. READ_ALL_AVAILABLE, NI-DAQmx determines how many samples to read based on if the task acquires samples continuously or
acquires a finite number of samples.
If the task acquires samples continuously and you set this input to
nidaqmx.constants.READ_ALL_AVAILABLE, this method reads all the samples
currently available in the buffer.

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If the task acquires a finite number of samples and you set this input to
nidaqmx.constants.READ_ALL_AVAILABLE, the method waits for the task to acquire
all requested samples, then reads those samples. If you set the “read_all_avail_samp”
property to True, the method reads the samples currently available in the buffer and does
not wait for the task to acquire all requested samples.
• timeout (Optional[float]) – Specifies the amount of time in seconds to wait for
samples to become available. If the time elapses, the method returns an error and any
samples read before the timeout elapsed. The default timeout is 10 seconds. If you set
timeout to nidaqmx.constants.WAIT_INFINITELY, the method waits indefinitely. If you
set timeout to 0, the method tries once to read the requested samples and returns an error
if it is unable to.
Returns Indicates the number of samples acquired by each channel. NI-DAQmx returns a single
value because this value is the same for all channels.
Return type int
read_one_sample(timeout=10)
Reads a single floating-point sample from a single analog input channel in a task.
Parameters timeout (Optional[float]) – Specifies the amount of time in seconds to
wait for samples to become available. If the time elapses, the method returns an error and
any samples read before the timeout elapsed. The default timeout is 10 seconds. If you set
timeout to nidaqmx.constants.WAIT_INFINITELY, the method waits indefinitely. If you set
timeout to 0, the method tries once to read the requested samples and returns an error if it is
unable to.
Returns Indicates a single floating-point sample from the task.
Return type float
verify_array_shape
bool – Indicates whether the size and shape of the user-defined NumPy arrays passed to read methods are
verified. Defaults to True when this object is instantiated.
Setting this property to True may marginally adversely impact the performance of read methods.
class nidaqmx.stream_readers.AnalogMultiChannelReader(task_in_stream)
Bases: nidaqmx.stream_readers.ChannelReaderBase
Reads samples from one or more analog input channels in an NI-DAQmx task.
read_many_sample(data, number_of_samples_per_channel=-1, timeout=10.0)
Reads one or more floating-point samples from one or more analog input channels in a task.
This read method accepts a preallocated NumPy array to hold the samples requested, which can be advantageous for performance and interoperability with NumPy and SciPy.
Passing in a preallocated array is valuable in continuous acquisition scenarios, where the same array can
be used repeatedly in each call to the method.
Parameters
• data (numpy.ndarray) – Specifies a preallocated 2D NumPy array of floating-point
values to hold the samples requested. The size of the array must be large enough to hold
all requested samples from all channels in the task; otherwise, an error is thrown.
Each row corresponds to a channel in the task. Each column corresponds to a sample
from each channel. The order of the channels in the array corresponds to the order in
which you add the channels to the task or to the order of the channels you specify with the
“channels_to_read” property.

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If the size of the array is too large or the array is shaped incorrectly, the previous statement may not hold true as the samples read may not be separated into rows and columns
properly. Set the “verify_array_shape” property on this channel reader object to True to
validate that the NumPy array object is shaped properly. Setting this property to True may
marginally adversely impact the performance of the method.
• number_of_samples_per_channel (Optional[int]) – Specifies the number
of samples to read.
If you set this input to nidaqmx.constants. READ_ALL_AVAILABLE, NI-DAQmx determines how many samples to read based on if the task acquires samples continuously or
acquires a finite number of samples.
If the task acquires samples continuously and you set this input to
nidaqmx.constants.READ_ALL_AVAILABLE, this method reads all the samples
currently available in the buffer.
If the task acquires a finite number of samples and you set this input to
nidaqmx.constants.READ_ALL_AVAILABLE, the method waits for the task to acquire
all requested samples, then reads those samples. If you set the “read_all_avail_samp”
property to True, the method reads the samples currently available in the buffer and does
not wait for the task to acquire all requested samples.
• timeout (Optional[float]) – Specifies the amount of time in seconds to wait for
samples to become available. If the time elapses, the method returns an error and any
samples read before the timeout elapsed. The default timeout is 10 seconds. If you set
timeout to nidaqmx.constants.WAIT_INFINITELY, the method waits indefinitely. If you
set timeout to 0, the method tries once to read the requested samples and returns an error
if it is unable to.
Returns Indicates the number of samples acquired by each channel. NI-DAQmx returns a single
value because this value is the same for all channels.
Return type int
read_one_sample(data, timeout=10)
Reads a single floating-point sample from one or more analog input channels in a task.
This read method accepts a preallocated NumPy array to hold the samples requested, which can be advantageous for performance and interoperability with NumPy and SciPy.
Passing in a preallocated array is valuable in continuous acquisition scenarios, where the same array can
be used repeatedly in each call to the method.
Parameters
• data (numpy.ndarray) – Specifies a preallocated 1D NumPy array of floating-point
values to hold the samples requested.
Each element in the array corresponds to a sample from each channel. The size of the
array must be large enough to hold all requested samples from the channel in the task;
otherwise, an error is thrown.
• timeout (Optional[float]) – Specifies the amount of time in seconds to wait for
samples to become available. If the time elapses, the method returns an error and any
samples read before the timeout elapsed. The default timeout is 10 seconds. If you set
timeout to nidaqmx.constants.WAIT_INFINITELY, the method waits indefinitely. If you
set timeout to 0, the method tries once to read the requested samples and returns an error
if it is unable to.

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verify_array_shape
bool – Indicates whether the size and shape of the user-defined NumPy arrays passed to read methods are
verified. Defaults to True when this object is instantiated.
Setting this property to True may marginally adversely impact the performance of read methods.
class nidaqmx.stream_readers.AnalogUnscaledReader(task_in_stream)
Bases: nidaqmx.stream_readers.ChannelReaderBase
Reads unscaled samples from one or more analog input channels in an NI-DAQmx task.
read_int16(data, number_of_samples_per_channel=-1, timeout=10.0)
Reads one or more unscaled 16-bit integer samples from one or more analog input channels in a task.
This read method accepts a preallocated NumPy array to hold the samples requested, which can be advantageous for performance and interoperability with NumPy and SciPy.
Passing in a preallocated array is valuable in continuous acquisition scenarios, where the same array can
be used repeatedly in each call to the method.
Parameters
• data (numpy.ndarray) – Specifies a preallocated 2D NumPy array of unscaled 16-bit
integer values to hold the samples requested. The size of the array must be large enough
to hold all requested samples from all channels in the task; otherwise, an error is thrown.
Each row corresponds to a channel in the task. Each column corresponds to a sample
from each channel. The order of the channels in the array corresponds to the order in
which you add the channels to the task or to the order of the channels you specify with the
“channels_to_read” property.
If the size of the array is too large or the array is shaped incorrectly, the previous statement
may not hold true as the samples read may not be separated into rows and columns properly. Set the “verify_array_shape” property on this channel reader object to True to validate that the NumPy array object is shaped properly. Setting this property may marginally
adversely impact the performance of the method.
• number_of_samples_per_channel (Optional[int]) – Specifies the number
of samples to read.
If you set this input to nidaqmx.constants. READ_ALL_AVAILABLE, NI-DAQmx determines how many samples to read based on if the task acquires samples continuously or
acquires a finite number of samples.
If the task acquires samples continuously and you set this input to
nidaqmx.constants.READ_ALL_AVAILABLE, this method reads all the samples
currently available in the buffer.
If the task acquires a finite number of samples and you set this input to
nidaqmx.constants.READ_ALL_AVAILABLE, the method waits for the task to acquire
all requested samples, then reads those samples. If you set the “read_all_avail_samp”
property to True, the method reads the samples currently available in the buffer and does
not wait for the task to acquire all requested samples.
• timeout (Optional[float]) – Specifies the amount of time in seconds to wait for
samples to become available. If the time elapses, the method returns an error and any
samples read before the timeout elapsed. The default timeout is 10 seconds. If you set
timeout to nidaqmx.constants.WAIT_INFINITELY, the method waits indefinitely. If you
set timeout to 0, the method tries once to read the requested samples and returns an error
if it is unable to.

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Returns Indicates the number of samples acquired by each channel. NI-DAQmx returns a single
value because this value is the same for all channels.
Return type int
read_int32(data, number_of_samples_per_channel=-1, timeout=10.0)
Reads one or more unscaled 32-bit integer samples from one or more analog input channels in a task.
This read method accepts a preallocated NumPy array to hold the samples requested, which can be advantageous for performance and interoperability with NumPy and SciPy.
Passing in a preallocated array is valuable in continuous acquisition scenarios, where the same array can
be used repeatedly in each call to the method.
Parameters
• data (numpy.ndarray) – Specifies a preallocated 2D NumPy array of unscaled 32-bit
integer values to hold the samples requested. The size of the array must be large enough
to hold all requested samples from all channels in the task; otherwise, an error is thrown.
Each row corresponds to a channel in the task. Each column corresponds to a sample
from each channel. The order of the channels in the array corresponds to the order in
which you add the channels to the task or to the order of the channels you specify with the
“channels_to_read” property.
If the size of the array is too large or the array is shaped incorrectly, the previous statement
may not hold true as the samples read may not be separated into rows and columns properly. Set the “verify_array_shape” property on this channel reader object to True to validate that the NumPy array object is shaped properly. Setting this property may marginally
adversely impact the performance of the method.
• number_of_samples_per_channel (Optional[int]) – Specifies the number
of samples to read.
If you set this input to nidaqmx.constants. READ_ALL_AVAILABLE, NI-DAQmx determines how many samples to read based on if the task acquires samples continuously or
acquires a finite number of samples.
If the task acquires samples continuously and you set this input to
nidaqmx.constants.READ_ALL_AVAILABLE, this method reads all the samples
currently available in the buffer.
If the task acquires a finite number of samples and you set this input to
nidaqmx.constants.READ_ALL_AVAILABLE, the method waits for the task to acquire
all requested samples, then reads those samples. If you set the “read_all_avail_samp”
property to True, the method reads the samples currently available in the buffer and does
not wait for the task to acquire all requested samples.
• timeout (Optional[float]) – Specifies the amount of time in seconds to wait for
samples to become available. If the time elapses, the method returns an error and any
samples read before the timeout elapsed. The default timeout is 10 seconds. If you set
timeout to nidaqmx.constants.WAIT_INFINITELY, the method waits indefinitely. If you
set timeout to 0, the method tries once to read the requested samples and returns an error
if it is unable to.
Returns Indicates the number of samples acquired by each channel. NI-DAQmx returns a single
value because this value is the same for all channels.
Return type int

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read_uint16(data, number_of_samples_per_channel=-1, timeout=10.0)
Reads one or more unscaled 16-bit unsigned integer samples from one or more analog input channels in a
task.
This read method accepts a preallocated NumPy array to hold the samples requested, which can be advantageous for performance and interoperability with NumPy and SciPy.
Passing in a preallocated array is valuable in continuous acquisition scenarios, where the same array can
be used repeatedly in each call to the method.
Parameters
• data (numpy.ndarray) – Specifies a preallocated 2D NumPy array of unscaled 16-bit
unsigned integer values to hold the samples requested. The size of the array must be large
enough to hold all requested samples from all channels in the task; otherwise, an error is
thrown.
Each row corresponds to a channel in the task. Each column corresponds to a sample
from each channel. The order of the channels in the array corresponds to the order in
which you add the channels to the task or to the order of the channels you specify with the
“channels_to_read” property.
If the size of the array is too large or the array is shaped incorrectly, the previous statement
may not hold true as the samples read may not be separated into rows and columns properly. Set the “verify_array_shape” property on this channel reader object to True to validate that the NumPy array object is shaped properly. Setting this property may marginally
adversely impact the performance of the method.
• number_of_samples_per_channel (Optional[int]) – Specifies the number
of samples to read.
If you set this input to nidaqmx.constants. READ_ALL_AVAILABLE, NI-DAQmx determines how many samples to read based on if the task acquires samples continuously or
acquires a finite number of samples.
If the task acquires samples continuously and you set this input to
nidaqmx.constants.READ_ALL_AVAILABLE, this method reads all the samples
currently available in the buffer.
If the task acquires a finite number of samples and you set this input to
nidaqmx.constants.READ_ALL_AVAILABLE, the method waits for the task to acquire
all requested samples, then reads those samples. If you set the “read_all_avail_samp”
property to True, the method reads the samples currently available in the buffer and does
not wait for the task to acquire all requested samples.
• timeout (Optional[float]) – Specifies the amount of time in seconds to wait for
samples to become available. If the time elapses, the method returns an error and any
samples read before the timeout elapsed. The default timeout is 10 seconds. If you set
timeout to nidaqmx.constants.WAIT_INFINITELY, the method waits indefinitely. If you
set timeout to 0, the method tries once to read the requested samples and returns an error
if it is unable to.
Returns Indicates the number of samples acquired by each channel. NI-DAQmx returns a single
value because this value is the same for all channels.
Return type int
read_uint32(data, number_of_samples_per_channel=-1, timeout=10.0)
Reads one or more unscaled unsigned 32-bit integer samples from one or more analog input channels in a
task.

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This read method accepts a preallocated NumPy array to hold the samples requested, which can be advantageous for performance and interoperability with NumPy and SciPy.
Passing in a preallocated array is valuable in continuous acquisition scenarios, where the same array can
be used repeatedly in each call to the method.
Parameters
• data (numpy.ndarray) – Specifies a preallocated 2D NumPy array of unscaled 32-bit
unsigned integer values to hold the samples requested. The size of the array must be large
enough to hold all requested samples from all channels in the task; otherwise, an error is
thrown.
Each row corresponds to a channel in the task. Each column corresponds to a sample
from each channel. The order of the channels in the array corresponds to the order in
which you add the channels to the task or to the order of the channels you specify with the
“channels_to_read” property.
If the size of the array is too large or the array is shaped incorrectly, the previous statement
may not hold true as the samples read may not be separated into rows and columns properly. Set the “verify_array_shape” property on this channel reader object to True to validate that the NumPy array object is shaped properly. Setting this property may marginally
adversely impact the performance of the method.
• number_of_samples_per_channel (Optional[int]) – Specifies the number
of samples to read.
If you set this input to nidaqmx.constants. READ_ALL_AVAILABLE, NI-DAQmx determines how many samples to read based on if the task acquires samples continuously or
acquires a finite number of samples.
If the task acquires samples continuously and you set this input to
nidaqmx.constants.READ_ALL_AVAILABLE, this method reads all the samples
currently available in the buffer.
If the task acquires a finite number of samples and you set this input to
nidaqmx.constants.READ_ALL_AVAILABLE, the method waits for the task to acquire
all requested samples, then reads those samples. If you set the “read_all_avail_samp”
property to True, the method reads the samples currently available in the buffer and does
not wait for the task to acquire all requested samples.
• timeout (Optional[float]) – Specifies the amount of time in seconds to wait for
samples to become available. If the time elapses, the method returns an error and any
samples read before the timeout elapsed. The default timeout is 10 seconds. If you set
timeout to nidaqmx.constants.WAIT_INFINITELY, the method waits indefinitely. If you
set timeout to 0, the method tries once to read the requested samples and returns an error
if it is unable to.
Returns Indicates the number of samples acquired by each channel. NI-DAQmx returns a single
value because this value is the same for all channels.
Return type int
verify_array_shape
bool – Indicates whether the size and shape of the user-defined NumPy arrays passed to read methods are
verified. Defaults to True when this object is instantiated.
Setting this property to True may marginally adversely impact the performance of read methods.
class nidaqmx.stream_readers.CounterReader(task_in_stream)
Bases: nidaqmx.stream_readers.ChannelReaderBase

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Reads samples from a counter input channel in an NI-DAQmx task.
read_many_sample_double(data, number_of_samples_per_channel=-1, timeout=10.0)
Reads one or more floating-point samples from a single counter input channel in a task.
This read method accepts a preallocated NumPy array to hold the samples requested, which can be advantageous for performance and interoperability with NumPy and SciPy.
Passing in a preallocated array is valuable in continuous acquisition scenarios, where the same array can
be used repeatedly in each call to the method.
Parameters
• data (numpy.ndarray) – Specifies a preallocated 1D NumPy array of floating-point
values to hold the samples requested.
Each element in the array corresponds to a sample from the channel. The size of the array
must be large enough to hold all requested samples from the channel in the task; otherwise,
an error is thrown.
• number_of_samples_per_channel (Optional[int]) – Specifies the number
of samples to read.
If you set this input to nidaqmx.constants. READ_ALL_AVAILABLE, NI-DAQmx determines how many samples to read based on if the task acquires samples continuously or
acquires a finite number of samples.
If the task acquires samples continuously and you set this input to
nidaqmx.constants.READ_ALL_AVAILABLE, this method reads all the samples
currently available in the buffer.
If the task acquires a finite number of samples and you set this input to
nidaqmx.constants.READ_ALL_AVAILABLE, the method waits for the task to acquire
all requested samples, then reads those samples. If you set the “read_all_avail_samp”
property to True, the method reads the samples currently available in the buffer and does
not wait for the task to acquire all requested samples.
• timeout (Optional[float]) – Specifies the amount of time in seconds to wait for
samples to become available. If the time elapses, the method returns an error and any
samples read before the timeout elapsed. The default timeout is 10 seconds. If you set
timeout to nidaqmx.constants.WAIT_INFINITELY, the method waits indefinitely. If you
set timeout to 0, the method tries once to read the requested samples and returns an error
if it is unable to.
Returns Indicates the number of samples acquired by each channel. NI-DAQmx returns a single
value because this value is the same for all channels.
Return type int
read_many_sample_pulse_frequency(frequencies,
duty_cycles,
number_of_samples_per_channel=-1, timeout=10.0)
Reads one or more pulse samples in terms of frequency from a single counter input channel in a task.
This read method accepts preallocated NumPy arrays to hold the samples requested, which can be advantageous for performance and interoperability with NumPy and SciPy.
Passing in preallocated arrays is valuable in continuous acquisition scenarios, where the same array can be
used repeatedly in each call to the method.
Parameters
• frequencies (numpy.ndarray) – Specifies a preallocated 1D NumPy array of
floating-point values to hold the frequency portion of the pulse samples requested.

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Each element in the array corresponds to a sample from the channel. The size of the array
must be large enough to hold all requested samples from the channel in the task; otherwise,
an error is thrown.
• duty_cycles (numpy.ndarray) – Specifies a preallocated 1D NumPy array of
floating-point values to hold the duty cycle portion of the pulse samples requested.
Each element in the array corresponds to a sample from the channel. The size of the array
must be large enough to hold all requested samples from the channel in the task; otherwise,
an error is thrown.
• number_of_samples_per_channel (Optional[int]) – Specifies the number
of samples to read.
If you set this input to nidaqmx.constants. READ_ALL_AVAILABLE, NI-DAQmx determines how many samples to read based on if the task acquires samples continuously or
acquires a finite number of samples.
If the task acquires samples continuously and you set this input to
nidaqmx.constants.READ_ALL_AVAILABLE, this method reads all the samples
currently available in the buffer.
If the task acquires a finite number of samples and you set this input to
nidaqmx.constants.READ_ALL_AVAILABLE, the method waits for the task to acquire
all requested samples, then reads those samples. If you set the “read_all_avail_samp”
property to True, the method reads the samples currently available in the buffer and does
not wait for the task to acquire all requested samples.
• timeout (Optional[float]) – Specifies the amount of time in seconds to wait for
samples to become available. If the time elapses, the method returns an error and any
samples read before the timeout elapsed. The default timeout is 10 seconds. If you set
timeout to nidaqmx.constants.WAIT_INFINITELY, the method waits indefinitely. If you
set timeout to 0, the method tries once to read the requested samples and returns an error
if it is unable to.
Returns Indicates the number of samples acquired by each channel. NI-DAQmx returns a single
value because this value is the same for all channels.
Return type int
read_many_sample_pulse_ticks(high_ticks, low_ticks, number_of_samples_per_channel=-1,
timeout=10.0)
Reads one or more pulse samples in terms of ticks from a single counter input channel in a task.
This read method accepts preallocated NumPy arrays to hold the samples requested, which can be advantageous for performance and interoperability with NumPy and SciPy.
Passing in preallocated arrays is valuable in continuous acquisition scenarios, where the same array can be
used repeatedly in each call to the method.
Parameters
• high_ticks (numpy.ndarray) – Specifies a preallocated 1D NumPy array of 32-bit
unsigned integer values to hold the high ticks portion of the pulse samples requested.
Each element in the array corresponds to a sample from the channel. The size of the array
must be large enough to hold all requested samples from the channel in the task; otherwise,
an error is thrown.
• low_ticks (numpy.ndarray) – Specifies a preallocated 1D NumPy array of 32-bit
unsigned integer values to hold the low ticks portion of the pulse samples requested.

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Each element in the array corresponds to a sample from the channel. The size of the array
must be large enough to hold all requested samples from the channel in the task; otherwise,
an error is thrown.
• number_of_samples_per_channel (Optional[int]) – Specifies the number
of samples to read.
If you set this input to nidaqmx.constants. READ_ALL_AVAILABLE, NI-DAQmx determines how many samples to read based on if the task acquires samples continuously or
acquires a finite number of samples.
If the task acquires samples continuously and you set this input to
nidaqmx.constants.READ_ALL_AVAILABLE, this method reads all the samples
currently available in the buffer.
If the task acquires a finite number of samples and you set this input to
nidaqmx.constants.READ_ALL_AVAILABLE, the method waits for the task to acquire
all requested samples, then reads those samples. If you set the “read_all_avail_samp”
property to True, the method reads the samples currently available in the buffer and does
not wait for the task to acquire all requested samples.
• timeout (Optional[float]) – Specifies the amount of time in seconds to wait for
samples to become available. If the time elapses, the method returns an error and any
samples read before the timeout elapsed. The default timeout is 10 seconds. If you set
timeout to nidaqmx.constants.WAIT_INFINITELY, the method waits indefinitely. If you
set timeout to 0, the method tries once to read the requested samples and returns an error
if it is unable to.
Returns Indicates the number of samples acquired by each channel. NI-DAQmx returns a single
value because this value is the same for all channels.
Return type int
read_many_sample_pulse_time(high_times, low_times, number_of_samples_per_channel=-1,
timeout=10.0)
Reads one or more pulse samples in terms of time from a single counter input channel in a task.
This read method accepts preallocated NumPy arrays to hold the samples requested, which can be advantageous for performance and interoperability with NumPy and SciPy.
Passing in preallocated arrays is valuable in continuous acquisition scenarios, where the same array can be
used repeatedly in each call to the method.
Parameters
• high_times (numpy.ndarray) – Specifies a preallocated 1D NumPy array of
floating-point values to hold the high time portion of the pulse samples requested.
Each element in the array corresponds to a sample from the channel. The size of the array
must be large enough to hold all requested samples from the channel in the task; otherwise,
an error is thrown.
• low_times (numpy.ndarray) – Specifies a preallocated 1D NumPy array of
floating-point values to hold the low time portion of the pulse samples requested.
Each element in the array corresponds to a sample from the channel. The size of the array
must be large enough to hold all requested samples from the channel in the task; otherwise,
an error is thrown.
• number_of_samples_per_channel (Optional[int]) – Specifies the number
of samples to read.

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If you set this input to nidaqmx.constants. READ_ALL_AVAILABLE, NI-DAQmx determines how many samples to read based on if the task acquires samples continuously or
acquires a finite number of samples.
If the task acquires samples continuously and you set this input to
nidaqmx.constants.READ_ALL_AVAILABLE, this method reads all the samples
currently available in the buffer.
If the task acquires a finite number of samples and you set this input to
nidaqmx.constants.READ_ALL_AVAILABLE, the method waits for the task to acquire
all requested samples, then reads those samples. If you set the “read_all_avail_samp”
property to True, the method reads the samples currently available in the buffer and does
not wait for the task to acquire all requested samples.
• timeout (Optional[float]) – Specifies the amount of time in seconds to wait for
samples to become available. If the time elapses, the method returns an error and any
samples read before the timeout elapsed. The default timeout is 10 seconds. If you set
timeout to nidaqmx.constants.WAIT_INFINITELY, the method waits indefinitely. If you
set timeout to 0, the method tries once to read the requested samples and returns an error
if it is unable to.
Returns Indicates the number of samples acquired by each channel. NI-DAQmx returns a single
value because this value is the same for all channels.
Return type int
read_many_sample_uint32(data, number_of_samples_per_channel=-1, timeout=10.0)
Reads one or more 32-bit unsigned integer samples from a single counter input channel in a task.
This read method accepts a preallocated NumPy array to hold the samples requested, which can be advantageous for performance and interoperability with NumPy and SciPy.
Passing in a preallocated array is valuable in continuous acquisition scenarios, where the same array can
be used repeatedly in each call to the method.
Parameters
• data (numpy.ndarray) – Specifies a preallocated 1D NumPy array of 32-bit unsigned
integer values to hold the samples requested.
Each element in the array corresponds to a sample from the channel. The size of the array
must be large enough to hold all requested samples from the channel in the task; otherwise,
an error is thrown.
• number_of_samples_per_channel (Optional[int]) – Specifies the number
of samples to read.
If you set this input to nidaqmx.constants. READ_ALL_AVAILABLE, NI-DAQmx determines how many samples to read based on if the task acquires samples continuously or
acquires a finite number of samples.
If the task acquires samples continuously and you set this input to
nidaqmx.constants.READ_ALL_AVAILABLE, this method reads all the samples
currently available in the buffer.
If the task acquires a finite number of samples and you set this input to
nidaqmx.constants.READ_ALL_AVAILABLE, the method waits for the task to acquire
all requested samples, then reads those samples. If you set the “read_all_avail_samp”
property to True, the method reads the samples currently available in the buffer and does
not wait for the task to acquire all requested samples.

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• timeout (Optional[float]) – Specifies the amount of time in seconds to wait for
samples to become available. If the time elapses, the method returns an error and any
samples read before the timeout elapsed. The default timeout is 10 seconds. If you set
timeout to nidaqmx.constants.WAIT_INFINITELY, the method waits indefinitely. If you
set timeout to 0, the method tries once to read the requested samples and returns an error
if it is unable to.
Returns Indicates the number of samples acquired by each channel. NI-DAQmx returns a single
value because this value is the same for all channels.
Return type int
read_one_sample_double(timeout=10)
Reads a single floating-point sample from a single counter input channel in a task.
Parameters timeout (Optional[float]) – Specifies the amount of time in seconds to
wait for samples to become available. If the time elapses, the method returns an error and
any samples read before the timeout elapsed. The default timeout is 10 seconds. If you set
timeout to nidaqmx.constants.WAIT_INFINITELY, the method waits indefinitely. If you set
timeout to 0, the method tries once to read the requested samples and returns an error if it is
unable to.
Returns
Indicates a single floating-point sample from the task.
Return type float
read_one_sample_pulse_frequency(timeout=10)
Reads a pulse sample in terms of frequency from a single counter input channel in a task.
Parameters timeout (Optional[float]) – Specifies the amount of time in seconds to
wait for samples to become available. If the time elapses, the method returns an error and
any samples read before the timeout elapsed. The default timeout is 10 seconds. If you set
timeout to nidaqmx.constants.WAIT_INFINITELY, the method waits indefinitely. If you set
timeout to 0, the method tries once to read the requested samples and returns an error if it is
unable to.
Returns Indicates a pulse sample in terms of frequency from the task.
Return type nidaqmx.types.CtrFreq
read_one_sample_pulse_ticks(timeout=10)
Reads a pulse sample in terms of ticks from a single counter input channel in a task.
Parameters timeout (Optional[float]) – Specifies the amount of time in seconds to
wait for samples to become available. If the time elapses, the method returns an error and
any samples read before the timeout elapsed. The default timeout is 10 seconds. If you set
timeout to nidaqmx.constants.WAIT_INFINITELY, the method waits indefinitely. If you set
timeout to 0, the method tries once to read the requested samples and returns an error if it is
unable to.
Returns Indicates a pulse sample in terms of ticks from the task.
Return type nidaqmx.types.CtrTick
read_one_sample_pulse_time(timeout=10)
Reads a pulse sample in terms of time from a single counter input channel in a task.
Parameters timeout (Optional[float]) – Specifies the amount of time in seconds to
wait for samples to become available. If the time elapses, the method returns an error and
any samples read before the timeout elapsed. The default timeout is 10 seconds. If you set

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timeout to nidaqmx.constants.WAIT_INFINITELY, the method waits indefinitely. If you set
timeout to 0, the method tries once to read the requested samples and returns an error if it is
unable to.
Returns Indicates a pulse sample in terms of time from the task.
Return type nidaqmx.types.CtrTime
read_one_sample_uint32(timeout=10)
Reads a single 32-bit unsigned integer sample from a single counter input channel in a task.
Parameters timeout (Optional[float]) – Specifies the amount of time in seconds to
wait for samples to become available. If the time elapses, the method returns an error and
any samples read before the timeout elapsed. The default timeout is 10 seconds. If you set
timeout to nidaqmx.constants.WAIT_INFINITELY, the method waits indefinitely. If you set
timeout to 0, the method tries once to read the requested samples and returns an error if it is
unable to.
Returns Indicates a single 32-bit unsigned integer sample from the task.
Return type int
verify_array_shape
bool – Indicates whether the size and shape of the user-defined NumPy arrays passed to read methods are
verified. Defaults to True when this object is instantiated.
Setting this property to True may marginally adversely impact the performance of read methods.
class nidaqmx.stream_readers.DigitalSingleChannelReader(task_in_stream)
Bases: nidaqmx.stream_readers.ChannelReaderBase
Reads samples from a digital input channel in an NI-DAQmx task.
read_many_sample_port_byte(data, number_of_samples_per_channel=-1, timeout=10.0)
Reads one or more 8-bit unsigned integer samples from a single digital input channel in a task.
Use this method for devices with up to 8 lines per port.
This read method accepts a preallocated NumPy array to hold the samples requested, which can be advantageous for performance and interoperability with NumPy and SciPy.
Passing in a preallocated array is valuable in continuous acquisition scenarios, where the same array can
be used repeatedly in each call to the method.
Parameters
• data (numpy.ndarray) – Specifies a preallocated 1D NumPy array of 8-bit unsigned
integer values to hold the samples requested.
Each element in the array corresponds to a sample from the channel. The size of the array
must be large enough to hold all requested samples from the channel in the task; otherwise,
an error is thrown.
• number_of_samples_per_channel (Optional[int]) – Specifies the number
of samples to read.
If you set this input to nidaqmx.constants. READ_ALL_AVAILABLE, NI-DAQmx determines how many samples to read based on if the task acquires samples continuously or
acquires a finite number of samples.
If the task acquires samples continuously and you set this input to
nidaqmx.constants.READ_ALL_AVAILABLE, this method reads all the samples
currently available in the buffer.

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If the task acquires a finite number of samples and you set this input to
nidaqmx.constants.READ_ALL_AVAILABLE, the method waits for the task to acquire
all requested samples, then reads those samples. If you set the “read_all_avail_samp”
property to True, the method reads the samples currently available in the buffer and does
not wait for the task to acquire all requested samples.
• timeout (Optional[float]) – Specifies the amount of time in seconds to wait for
samples to become available. If the time elapses, the method returns an error and any
samples read before the timeout elapsed. The default timeout is 10 seconds. If you set
timeout to nidaqmx.constants.WAIT_INFINITELY, the method waits indefinitely. If you
set timeout to 0, the method tries once to read the requested samples and returns an error
if it is unable to.
Returns Indicates the number of samples acquired by each channel. NI-DAQmx returns a single
value because this value is the same for all channels.
Return type int
read_many_sample_port_uint16(data, number_of_samples_per_channel=-1, timeout=10.0)
Reads one or more 16-bit unsigned integer samples from a single digital input channel in a task.
Use this method for devices with up to 16 lines per port.
This read method accepts a preallocated NumPy array to hold the samples requested, which can be advantageous for performance and interoperability with NumPy and SciPy.
Passing in a preallocated array is valuable in continuous acquisition scenarios, where the same array can
be used repeatedly in each call to the method.
Parameters
• data (numpy.ndarray) – Specifies a preallocated 1D NumPy array of 16-bit unsigned
integer values to hold the samples requested.
Each element in the array corresponds to a sample from the channel. The size of the array
must be large enough to hold all requested samples from the channel in the task; otherwise,
an error is thrown.
• number_of_samples_per_channel (Optional[int]) – Specifies the number
of samples to read.
If you set this input to nidaqmx.constants. READ_ALL_AVAILABLE, NI-DAQmx determines how many samples to read based on if the task acquires samples continuously or
acquires a finite number of samples.
If the task acquires samples continuously and you set this input to
nidaqmx.constants.READ_ALL_AVAILABLE, this method reads all the samples
currently available in the buffer.
If the task acquires a finite number of samples and you set this input to
nidaqmx.constants.READ_ALL_AVAILABLE, the method waits for the task to acquire
all requested samples, then reads those samples. If you set the “read_all_avail_samp”
property to True, the method reads the samples currently available in the buffer and does
not wait for the task to acquire all requested samples.
• timeout (Optional[float]) – Specifies the amount of time in seconds to wait for
samples to become available. If the time elapses, the method returns an error and any
samples read before the timeout elapsed. The default timeout is 10 seconds. If you set
timeout to nidaqmx.constants.WAIT_INFINITELY, the method waits indefinitely. If you
set timeout to 0, the method tries once to read the requested samples and returns an error
if it is unable to.

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Returns Indicates the number of samples acquired by each channel. NI-DAQmx returns a single
value because this value is the same for all channels.
Return type int
read_many_sample_port_uint32(data, number_of_samples_per_channel=-1, timeout=10.0)
Reads one or more 32-bit unsigned integer samples from a single digital input channel in a task.
Use this method for devices with up to 32 lines per port.
This read method accepts a preallocated NumPy array to hold the samples requested, which can be advantageous for performance and interoperability with NumPy and SciPy.
Passing in a preallocated array is valuable in continuous acquisition scenarios, where the same array can
be used repeatedly in each call to the method.
Parameters
• data (numpy.ndarray) – Specifies a preallocated 1D NumPy array of 32-bit unsigned
integer values to hold the samples requested.
Each element in the array corresponds to a sample from the channel. The size of the array
must be large enough to hold all requested samples from the channel in the task; otherwise,
an error is thrown.
• number_of_samples_per_channel (Optional[int]) – Specifies the number
of samples to read.
If you set this input to nidaqmx.constants. READ_ALL_AVAILABLE, NI-DAQmx determines how many samples to read based on if the task acquires samples continuously or
acquires a finite number of samples.
If the task acquires samples continuously and you set this input to
nidaqmx.constants.READ_ALL_AVAILABLE, this method reads all the samples
currently available in the buffer.
If the task acquires a finite number of samples and you set this input to
nidaqmx.constants.READ_ALL_AVAILABLE, the method waits for the task to acquire
all requested samples, then reads those samples. If you set the “read_all_avail_samp”
property to True, the method reads the samples currently available in the buffer and does
not wait for the task to acquire all requested samples.
• timeout (Optional[float]) – Specifies the amount of time in seconds to wait for
samples to become available. If the time elapses, the method returns an error and any
samples read before the timeout elapsed. The default timeout is 10 seconds. If you set
timeout to nidaqmx.constants.WAIT_INFINITELY, the method waits indefinitely. If you
set timeout to 0, the method tries once to read the requested samples and returns an error
if it is unable to.
Returns Indicates the number of samples acquired by each channel. NI-DAQmx returns a single
value because this value is the same for all channels.
Return type int
read_one_sample_multi_line(data, timeout=10)
Reads a single boolean sample from a single digital input channel in a task. The channel can contain
multiple digital lines.
This read method accepts a preallocated NumPy array to hold the samples requested, which can be advantageous for performance and interoperability with NumPy and SciPy.
Passing in a preallocated array is valuable in continuous acquisition scenarios, where the same array can
be used repeatedly in each call to the method.

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Parameters
• data (numpy.ndarray) – Specifies a preallocated 1D NumPy array of boolean values
to hold the samples requested.
Each element in the array corresponds to a sample from a line in the channel. The size of
the array must be large enough to hold all requested samples from the channel in the task;
otherwise, an error is thrown.
• timeout (Optional[float]) – Specifies the amount of time in seconds to wait for
samples to become available. If the time elapses, the method returns an error and any
samples read before the timeout elapsed. The default timeout is 10 seconds. If you set
timeout to nidaqmx.constants.WAIT_INFINITELY, the method waits indefinitely. If you
set timeout to 0, the method tries once to read the requested samples and returns an error
if it is unable to.
read_one_sample_one_line(timeout=10)
Reads a single boolean sample from a single digital input channel in a task. The channel can contain only
one digital line.
Parameters timeout (Optional[float]) – Specifies the amount of time in seconds to
wait for samples to become available. If the time elapses, the method returns an error and
any samples read before the timeout elapsed. The default timeout is 10 seconds. If you set
timeout to nidaqmx.constants.WAIT_INFINITELY, the method waits indefinitely. If you set
timeout to 0, the method tries once to read the requested samples and returns an error if it is
unable to.
Returns Indicates a single boolean sample from the task.
Return type bool
read_one_sample_port_byte(timeout=10)
Reads a single 8-bit unsigned integer sample from a single digital input channel in a task.
Use this method for devices with up to 8 lines per port.
Parameters timeout (Optional[float]) – Specifies the amount of time in seconds to
wait for samples to become available. If the time elapses, the method returns an error and
any samples read before the timeout elapsed. The default timeout is 10 seconds. If you set
timeout to nidaqmx.constants.WAIT_INFINITELY, the method waits indefinitely. If you set
timeout to 0, the method tries once to read the requested samples and returns an error if it is
unable to.
Returns Indicates a single 8-bit unsigned integer sample from the task.
Return type int
read_one_sample_port_uint16(timeout=10)
Reads a single 16-bit unsigned integer sample from a single digital input channel in a task.
Use this method for devices with up to 16 lines per port.
Parameters timeout (Optional[float]) – Specifies the amount of time in seconds to
wait for samples to become available. If the time elapses, the method returns an error and
any samples read before the timeout elapsed. The default timeout is 10 seconds. If you set
timeout to nidaqmx.constants.WAIT_INFINITELY, the method waits indefinitely. If you set
timeout to 0, the method tries once to read the requested samples and returns an error if it is
unable to.
Returns Indicates a single 16-bit unsigned integer sample from the task.
Return type int

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read_one_sample_port_uint32(timeout=10)
Reads a single 32-bit unsigned integer sample from a single digital input channel in a task.
Use this method for devices with up to 32 lines per port.
Parameters timeout (Optional[float]) – Specifies the amount of time in seconds to
wait for samples to become available. If the time elapses, the method returns an error and
any samples read before the timeout elapsed. The default timeout is 10 seconds. If you set
timeout to nidaqmx.constants.WAIT_INFINITELY, the method waits indefinitely. If you set
timeout to 0, the method tries once to read the requested samples and returns an error if it is
unable to.
Returns Indicates a single 32-bit unsigned integer sample from the task.
Return type int
verify_array_shape
bool – Indicates whether the size and shape of the user-defined NumPy arrays passed to read methods are
verified. Defaults to True when this object is instantiated.
Setting this property to True may marginally adversely impact the performance of read methods.
class nidaqmx.stream_readers.DigitalMultiChannelReader(task_in_stream)
Bases: nidaqmx.stream_readers.ChannelReaderBase
Reads samples from one or more digital input channels in an NI-DAQmx task.
read_many_sample_port_byte(data, number_of_samples_per_channel=-1, timeout=10.0)
Reads one or more 8-bit unsigned integer samples from one or more digital input channel in a task.
Use this method for devices with up to 8 lines per port.
This read method accepts a preallocated NumPy array to hold the samples requested, which can be advantageous for performance and interoperability with NumPy and SciPy.
Passing in a preallocated array is valuable in continuous acquisition scenarios, where the same array can
be used repeatedly in each call to the method.
Parameters
• data (numpy.ndarray) – Specifies a preallocated 2D NumPy array of 8-bit unsigned
integer values to hold the samples requested. The size of the array must be large enough
to hold all requested samples from all channels in the task; otherwise, an error is thrown.
Each row corresponds to a channel in the task. Each column corresponds to a sample
from each channel. The order of the channels in the array corresponds to the order in
which you add the channels to the task or to the order of the channels you specify with the
“channels_to_read” property.
If the size of the array is too large or the array is shaped incorrectly, the previous statement
may not hold true as the samples read may not be separated into rows and columns properly. Set the “verify_array_shape” property on this channel reader object to True to validate that the NumPy array object is shaped properly. Setting this property may marginally
adversely impact the performance of the method.
• number_of_samples_per_channel (Optional[int]) – Specifies the number
of samples to read.
If you set this input to nidaqmx.constants. READ_ALL_AVAILABLE, NI-DAQmx determines how many samples to read based on if the task acquires samples continuously or
acquires a finite number of samples.

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If the task acquires samples continuously and you set this input to
nidaqmx.constants.READ_ALL_AVAILABLE, this method reads all the samples
currently available in the buffer.
If the task acquires a finite number of samples and you set this input to
nidaqmx.constants.READ_ALL_AVAILABLE, the method waits for the task to acquire
all requested samples, then reads those samples. If you set the “read_all_avail_samp”
property to True, the method reads the samples currently available in the buffer and does
not wait for the task to acquire all requested samples.
• timeout (Optional[float]) – Specifies the amount of time in seconds to wait for
samples to become available. If the time elapses, the method returns an error and any
samples read before the timeout elapsed. The default timeout is 10 seconds. If you set
timeout to nidaqmx.constants.WAIT_INFINITELY, the method waits indefinitely. If you
set timeout to 0, the method tries once to read the requested samples and returns an error
if it is unable to.
Returns Indicates the number of samples acquired by each channel. NI-DAQmx returns a single
value because this value is the same for all channels.
Return type int
read_many_sample_port_uint16(data, number_of_samples_per_channel=-1, timeout=10.0)
Reads one or more 16-bit unsigned integer samples from one or more digital input channels in a task.
Use this method for devices with up to 16 lines per port.
This read method accepts a preallocated NumPy array to hold the samples requested, which can be advantageous for performance and interoperability with NumPy and SciPy.
Passing in a preallocated array is valuable in continuous acquisition scenarios, where the same array can
be used repeatedly in each call to the method.
Parameters
• data (numpy.ndarray) – Specifies a preallocated 2D NumPy array of 16-bit unsigned
integer values to hold the samples requested. The size of the array must be large enough
to hold all requested samples from all channels in the task; otherwise, an error is thrown.
Each row corresponds to a channel in the task. Each column corresponds to a sample
from each channel. The order of the channels in the array corresponds to the order in
which you add the channels to the task or to the order of the channels you specify with the
“channels_to_read” property.
If the size of the array is too large or the array is shaped incorrectly, the previous statement
may not hold true as the samples read may not be separated into rows and columns properly. Set the “verify_array_shape” property on this channel reader object to True to validate that the NumPy array object is shaped properly. Setting this property may marginally
adversely impact the performance of the method.
• number_of_samples_per_channel (Optional[int]) – Specifies the number
of samples to read.
If you set this input to nidaqmx.constants. READ_ALL_AVAILABLE, NI-DAQmx determines how many samples to read based on if the task acquires samples continuously or
acquires a finite number of samples.
If the task acquires samples continuously and you set this input to
nidaqmx.constants.READ_ALL_AVAILABLE, this method reads all the samples
currently available in the buffer.

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If the task acquires a finite number of samples and you set this input to
nidaqmx.constants.READ_ALL_AVAILABLE, the method waits for the task to acquire
all requested samples, then reads those samples. If you set the “read_all_avail_samp”
property to True, the method reads the samples currently available in the buffer and does
not wait for the task to acquire all requested samples.
• timeout (Optional[float]) – Specifies the amount of time in seconds to wait for
samples to become available. If the time elapses, the method returns an error and any
samples read before the timeout elapsed. The default timeout is 10 seconds. If you set
timeout to nidaqmx.constants.WAIT_INFINITELY, the method waits indefinitely. If you
set timeout to 0, the method tries once to read the requested samples and returns an error
if it is unable to.
Returns Indicates the number of samples acquired by each channel. NI-DAQmx returns a single
value because this value is the same for all channels.
Return type int
read_many_sample_port_uint32(data, number_of_samples_per_channel=-1, timeout=10.0)
Reads one or more 32-bit unsigned integer samples from one or more digital input channels in a task.
Use this method for devices with up to 32 lines per port.
This read method accepts a preallocated NumPy array to hold the samples requested, which can be advantageous for performance and interoperability with NumPy and SciPy.
Passing in a preallocated array is valuable in continuous acquisition scenarios, where the same array can
be used repeatedly in each call to the method.
Parameters
• data (numpy.ndarray) – Specifies a preallocated 2D NumPy array of 32-bit unsigned
integer values to hold the samples requested. The size of the array must be large enough
to hold all requested samples from all channels in the task; otherwise, an error is thrown.
Each row corresponds to a channel in the task. Each column corresponds to a sample
from each channel. The order of the channels in the array corresponds to the order in
which you add the channels to the task or to the order of the channels you specify with the
“channels_to_read” property.
If the size of the array is too large or the array is shaped incorrectly, the previous statement
may not hold true as the samples read may not be separated into rows and columns properly. Set the “verify_array_shape” property on this channel reader object to True to validate that the NumPy array object is shaped properly. Setting this property may marginally
adversely impact the performance of the method.
• number_of_samples_per_channel (Optional[int]) – Specifies the number
of samples to read.
If you set this input to nidaqmx.constants. READ_ALL_AVAILABLE, NI-DAQmx determines how many samples to read based on if the task acquires samples continuously or
acquires a finite number of samples.
If the task acquires samples continuously and you set this input to
nidaqmx.constants.READ_ALL_AVAILABLE, this method reads all the samples
currently available in the buffer.
If the task acquires a finite number of samples and you set this input to
nidaqmx.constants.READ_ALL_AVAILABLE, the method waits for the task to acquire
all requested samples, then reads those samples. If you set the “read_all_avail_samp”

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property to True, the method reads the samples currently available in the buffer and does
not wait for the task to acquire all requested samples.
• timeout (Optional[float]) – Specifies the amount of time in seconds to wait for
samples to become available. If the time elapses, the method returns an error and any
samples read before the timeout elapsed. The default timeout is 10 seconds. If you set
timeout to nidaqmx.constants.WAIT_INFINITELY, the method waits indefinitely. If you
set timeout to 0, the method tries once to read the requested samples and returns an error
if it is unable to.
Returns Indicates the number of samples acquired by each channel. NI-DAQmx returns a single
value because this value is the same for all channels.
Return type int
read_one_sample_multi_line(data, timeout=10)
Reads a single boolean sample from one or more digital input channels in a task. The channels can contain
multiple digital lines.
This read method accepts a preallocated NumPy array to hold the samples requested, which can be advantageous for performance and interoperability with NumPy and SciPy.
Passing in a preallocated array is valuable in continuous acquisition scenarios, where the same array can
be used repeatedly in each call to the method.
Parameters
• data (numpy.ndarray) – Specifies a preallocated 2D NumPy array of boolean values
to hold the samples requested. The size of the array must be large enough to hold all
requested samples from all channels in the task; otherwise, an error is thrown.
Each row corresponds to a channel in the task. Each column corresponds to a line from
each channel. The order of the channels in the array corresponds to the order in which
you add the channels to the task or to the order of the channels you specify with the
“channels_to_read” property.
If the size of the array is too large or the array is shaped incorrectly, the previous statement
may not hold true as the samples read may not be separated into rows and columns properly. Set the “verify_array_shape” property on this channel reader object to True to validate that the NumPy array object is shaped properly. Setting this property may marginally
adversely impact the performance of the method.
• timeout (Optional[float]) – Specifies the amount of time in seconds to wait for
samples to become available. If the time elapses, the method returns an error and any
samples read before the timeout elapsed. The default timeout is 10 seconds. If you set
timeout to nidaqmx.constants.WAIT_INFINITELY, the method waits indefinitely. If you
set timeout to 0, the method tries once to read the requested samples and returns an error
if it is unable to.
read_one_sample_one_line(data, timeout=10)
Reads a single boolean sample from one or more digital input channels in a task. The channel can contain
only one digital line.
This read method accepts a preallocated NumPy array to hold the samples requested, which can be advantageous for performance and interoperability with NumPy and SciPy.
Passing in a preallocated array is valuable in continuous acquisition scenarios, where the same array can
be used repeatedly in each call to the method.
Parameters

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• data (numpy.ndarray) – Specifies a preallocated 1D NumPy array of boolean values
to hold the samples requested.
Each element in the array corresponds to a sample from each channel. The size of the
array must be large enough to hold all requested samples from the channel in the task;
otherwise, an error is thrown.
• timeout (Optional[float]) – Specifies the amount of time in seconds to wait for
samples to become available. If the time elapses, the method returns an error and any
samples read before the timeout elapsed. The default timeout is 10 seconds. If you set
timeout to nidaqmx.constants.WAIT_INFINITELY, the method waits indefinitely. If you
set timeout to 0, the method tries once to read the requested samples and returns an error
if it is unable to.
read_one_sample_port_byte(data, timeout=10)
Reads a single 8-bit unsigned integer sample from one or more digital input channels in a task.
Use this method for devices with up to 8 lines per port.
This read method accepts a preallocated NumPy array to hold the samples requested, which can be advantageous for performance and interoperability with NumPy and SciPy.
Passing in a preallocated array is valuable in continuous acquisition scenarios, where the same array can
be used repeatedly in each call to the method.
Parameters
• data (numpy.ndarray) – Specifies a preallocated 1D NumPy array of 8-bit unsigned
integer values to hold the samples requested.
Each element in the array corresponds to a sample from each channel. The size of the
array must be large enough to hold all requested samples from the channel in the task;
otherwise, an error is thrown.
• timeout (Optional[float]) – Specifies the amount of time in seconds to wait for
samples to become available. If the time elapses, the method returns an error and any
samples read before the timeout elapsed. The default timeout is 10 seconds. If you set
timeout to nidaqmx.constants.WAIT_INFINITELY, the method waits indefinitely. If you
set timeout to 0, the method tries once to read the requested samples and returns an error
if it is unable to.
read_one_sample_port_uint16(data, timeout=10)
Reads a single 16-bit unsigned integer sample from one or more digital input channels in a task.
Use this method for devices with up to 16 lines per port.
This read method accepts a preallocated NumPy array to hold the samples requested, which can be advantageous for performance and interoperability with NumPy and SciPy.
Passing in a preallocated array is valuable in continuous acquisition scenarios, where the same array can
be used repeatedly in each call to the method.
Parameters
• data (numpy.ndarray) – Specifies a preallocated 1D NumPy array of 16-bit unsigned
integer values to hold the samples requested.
Each element in the array corresponds to a sample from each channel. The size of the
array must be large enough to hold all requested samples from the channel in the task;
otherwise, an error is thrown.
• timeout (Optional[float]) – Specifies the amount of time in seconds to wait for
samples to become available. If the time elapses, the method returns an error and any

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samples read before the timeout elapsed. The default timeout is 10 seconds. If you set
timeout to nidaqmx.constants.WAIT_INFINITELY, the method waits indefinitely. If you
set timeout to 0, the method tries once to read the requested samples and returns an error
if it is unable to.
read_one_sample_port_uint32(data, timeout=10)
Reads a single 32-bit unsigned integer sample from one or more digital input channels in a task.
Use this method for devices with up to 32 lines per port.
This read method accepts a preallocated NumPy array to hold the samples requested, which can be advantageous for performance and interoperability with NumPy and SciPy.
Passing in a preallocated array is valuable in continuous acquisition scenarios, where the same array can
be used repeatedly in each call to the method.
Parameters
• data (numpy.ndarray) – Specifies a preallocated 1D NumPy array of 32-bit unsigned
integer values to hold the samples requested.
Each element in the array corresponds to a sample from each channel. The size of the
array must be large enough to hold all requested samples from the channel in the task;
otherwise, an error is thrown.
• timeout (Optional[float]) – Specifies the amount of time in seconds to wait for
samples to become available. If the time elapses, the method returns an error and any
samples read before the timeout elapsed. The default timeout is 10 seconds. If you set
timeout to nidaqmx.constants.WAIT_INFINITELY, the method waits indefinitely. If you
set timeout to 0, the method tries once to read the requested samples and returns an error
if it is unable to.
verify_array_shape
bool – Indicates whether the size and shape of the user-defined NumPy arrays passed to read methods are
verified. Defaults to True when this object is instantiated.
Setting this property to True may marginally adversely impact the performance of read methods.

nidaqmx.stream_writers

class nidaqmx.stream_writers.AnalogSingleChannelWriter(task_out_stream,
auto_start=)
Bases: nidaqmx.stream_writers.ChannelWriterBase
Writes samples to an analog output channel in an NI-DAQmx task.
auto_start
bool – Specifies if the write method automatically starts the task if you did not explicitly start it with the
DAQmx Start Task method.
If you do not specify a value for this parameter, NI-DAQmx determines its value based on the type of write
method used. If you use a one sample write method, its value is True; conversely, if you use a many sample
write method, its value is False.
verify_array_shape
bool – Indicates whether the size and shape of the user-defined NumPy arrays passed to read methods are
verified. Defaults to True when this object is instantiated.
Setting this property to True may marginally adversely impact the performance of read methods.

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write_many_sample(data, timeout=10.0)
Writes one or more floating-point samples to a single analog output channel in a task.
If the task uses on-demand timing, this method returns only after the device generates all samples. Ondemand is the default timing type if you do not use the timing property on the task to configure a sample
timing type. If the task uses any timing type other than on-demand, this method returns immediately and
does not wait for the device to generate all samples. Your application must determine if the task is done to
ensure that the device generated all samples.
Parameters
• data (numpy.ndarray) – Contains a 1D NumPy array of floating-point samples to
write to the task. Each element of the array corresponds to a sample to write.
• timeout (Optional[float]) – Specifies the amount of time in seconds to wait for
the method to write all samples. NI-DAQmx performs a timeout check only if the method
must wait before it writes data. This method returns an error if the time elapses. The default timeout is 10 seconds. If you set timeout to nidaqmx.constants.WAIT_INFINITELY,
the method waits indefinitely. If you set timeout to 0, the method tries once to write the
submitted samples. If the method could not write all the submitted samples, it returns an
error and the number of samples successfully written.
Returns Specifies the actual number of samples this method successfully wrote.
Return type int
write_one_sample(data, timeout=10)
Writes a single floating-point sample to a single analog output channel in a task.
Parameters
• data (float) – Specifies the floating-point sample to write to the task.
• auto_start (Optional[bool]) – Specifies if this method automatically starts the
task if you did not explicitly start it with the DAQmx Start Task method.
• timeout (Optional[float]) – Specifies the amount of time in seconds to wait for
the method to write all samples. NI-DAQmx performs a timeout check only if the method
must wait before it writes data. This method returns an error if the time elapses. The default timeout is 10 seconds. If you set timeout to nidaqmx.constants.WAIT_INFINITELY,
the method waits indefinitely. If you set timeout to 0, the method tries once to write the
submitted samples. If the method could not write all the submitted samples, it returns an
error and the number of samples successfully written.

class nidaqmx.stream_writers.AnalogMultiChannelWriter(task_out_stream,
auto_start=)
Bases: nidaqmx.stream_writers.ChannelWriterBase
Writes samples to one or more analog output channels in an NI-DAQmx task.
auto_start
bool – Specifies if the write method automatically starts the task if you did not explicitly start it with the
DAQmx Start Task method.
If you do not specify a value for this parameter, NI-DAQmx determines its value based on the type of write
method used. If you use a one sample write method, its value is True; conversely, if you use a many sample
write method, its value is False.
verify_array_shape
bool – Indicates whether the size and shape of the user-defined NumPy arrays passed to read methods are
verified. Defaults to True when this object is instantiated.

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Setting this property to True may marginally adversely impact the performance of read methods.
write_many_sample(data, timeout=10.0)
Writes one or more floating-point samples to one or more analog output channels in a task.
If the task uses on-demand timing, this method returns only after the device generates all samples. Ondemand is the default timing type if you do not use the timing property on the task to configure a sample
timing type. If the task uses any timing type other than on-demand, this method returns immediately and
does not wait for the device to generate all samples. Your application must determine if the task is done to
ensure that the device generated all samples.
Parameters
• data (numpy.ndarray) – Contains a 2D NumPy array of floating-point samples to
write to the task.
Each row corresponds to a channel in the task. Each column corresponds to a sample to
write to each channel. The order of the channels in the array corresponds to the order in
which you add the channels to the task.
• timeout (Optional[float]) – Specifies the amount of time in seconds to wait for
the method to write all samples. NI-DAQmx performs a timeout check only if the method
must wait before it writes data. This method returns an error if the time elapses. The default timeout is 10 seconds. If you set timeout to nidaqmx.constants.WAIT_INFINITELY,
the method waits indefinitely. If you set timeout to 0, the method tries once to write the
submitted samples. If the method could not write all the submitted samples, it returns an
error and the number of samples successfully written.
Returns Specifies the actual number of samples this method successfully wrote to each channel
in the task.
Return type int
write_one_sample(data, timeout=10)
Writes a single floating-point sample to one or more analog output channels in a task.
Parameters
• data (numpy.ndarray) – Contains a 1D NumPy array of floating-point samples to
write to the task.
Each element of the array corresponds to a channel in the task. The order of the channels
in the array corresponds to the order in which you add the channels to the task.
• timeout (Optional[float]) – Specifies the amount of time in seconds to wait for
the method to write all samples. NI-DAQmx performs a timeout check only if the method
must wait before it writes data. This method returns an error if the time elapses. The default timeout is 10 seconds. If you set timeout to nidaqmx.constants.WAIT_INFINITELY,
the method waits indefinitely. If you set timeout to 0, the method tries once to write the
submitted samples. If the method could not write all the submitted samples, it returns an
error and the number of samples successfully written.
class nidaqmx.stream_writers.AnalogUnscaledWriter(task_out_stream,
auto_start=)
Bases: nidaqmx.stream_writers.ChannelWriterBase
Writes unscaled samples to one or more analog output channels in an NI-DAQmx task.
auto_start
bool – Specifies if the write method automatically starts the task if you did not explicitly start it with the
DAQmx Start Task method.

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If you do not specify a value for this parameter, NI-DAQmx determines its value based on the type of write
method used. If you use a one sample write method, its value is True; conversely, if you use a many sample
write method, its value is False.
verify_array_shape
bool – Indicates whether the size and shape of the user-defined NumPy arrays passed to read methods are
verified. Defaults to True when this object is instantiated.
Setting this property to True may marginally adversely impact the performance of read methods.
write_int16(data, timeout=10.0)
Writes one or more unscaled 16-bit integer samples to one or more analog output channels in a task.
If the task uses on-demand timing, this method returns only after the device generates all samples. Ondemand is the default timing type if you do not use the timing property on the task to configure a sample
timing type. If the task uses any timing type other than on-demand, this method returns immediately and
does not wait for the device to generate all samples. Your application must determine if the task is done to
ensure that the device generated all samples.
Parameters
• data (numpy.ndarray) – Contains a 2D NumPy array of unscaled 16-bit integer samples to write to the task.
Each row corresponds to a channel in the task. Each column corresponds to a sample to
write to each channel.
• timeout (Optional[float]) – Specifies the amount of time in seconds to wait for
the method to write all samples. NI-DAQmx performs a timeout check only if the method
must wait before it writes data. This method returns an error if the time elapses. The default timeout is 10 seconds. If you set timeout to nidaqmx.constants.WAIT_INFINITELY,
the method waits indefinitely. If you set timeout to 0, the method tries once to write the
submitted samples. If the method could not write all the submitted samples, it returns an
error and the number of samples successfully written.
Returns Specifies the actual number of samples this method successfully wrote to each channel
in the task.
Return type int
write_int32(data, timeout=10.0)
Writes one or more unscaled 32-bit integer samples to one or more analog output channels in a task.
If the task uses on-demand timing, this method returns only after the device generates all samples. Ondemand is the default timing type if you do not use the timing property on the task to configure a sample
timing type. If the task uses any timing type other than on-demand, this method returns immediately and
does not wait for the device to generate all samples. Your application must determine if the task is done to
ensure that the device generated all samples.
Parameters
• data (numpy.ndarray) – Contains a 2D NumPy array of unscaled 32-bit integer samples to write to the task.
Each row corresponds to a channel in the task. Each column corresponds to a sample to
write to each channel.
• timeout (Optional[float]) – Specifies the amount of time in seconds to wait for
the method to write all samples. NI-DAQmx performs a timeout check only if the method
must wait before it writes data. This method returns an error if the time elapses. The default timeout is 10 seconds. If you set timeout to nidaqmx.constants.WAIT_INFINITELY,
the method waits indefinitely. If you set timeout to 0, the method tries once to write the

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submitted samples. If the method could not write all the submitted samples, it returns an
error and the number of samples successfully written.
Returns Specifies the actual number of samples this method successfully wrote to each channel
in the task.
Return type int
write_uint16(data, timeout=10.0)
Writes one or more unscaled 16-bit unsigned integer samples to one or more analog output channels in a
task.
If the task uses on-demand timing, this method returns only after the device generates all samples. Ondemand is the default timing type if you do not use the timing property on the task to configure a sample
timing type. If the task uses any timing type other than on-demand, this method returns immediately and
does not wait for the device to generate all samples. Your application must determine if the task is done to
ensure that the device generated all samples.
Parameters
• data (numpy.ndarray) – Contains a 2D NumPy array of unscaled 16-bit unsigned
integer samples to write to the task.
Each row corresponds to a channel in the task. Each column corresponds to a sample to
write to each channel.
• timeout (Optional[float]) – Specifies the amount of time in seconds to wait for
the method to write all samples. NI-DAQmx performs a timeout check only if the method
must wait before it writes data. This method returns an error if the time elapses. The default timeout is 10 seconds. If you set timeout to nidaqmx.constants.WAIT_INFINITELY,
the method waits indefinitely. If you set timeout to 0, the method tries once to write the
submitted samples. If the method could not write all the submitted samples, it returns an
error and the number of samples successfully written.
Returns Specifies the actual number of samples this method successfully wrote to each channel
in the task.
Return type int
write_uint32(data, timeout=10.0)
Writes one or more unscaled 32-bit unsigned integer samples to one or more analog output channels in a
task.
If the task uses on-demand timing, this method returns only after the device generates all samples. Ondemand is the default timing type if you do not use the timing property on the task to configure a sample
timing type. If the task uses any timing type other than on-demand, this method returns immediately and
does not wait for the device to generate all samples. Your application must determine if the task is done to
ensure that the device generated all samples.
Parameters
• data (numpy.ndarray) – Contains a 2D NumPy array of unscaled 32-bit unsigned
integer samples to write to the task.
Each row corresponds to a channel in the task. Each column corresponds to a sample to
write to each channel.
• timeout (Optional[float]) – Specifies the amount of time in seconds to wait for
the method to write all samples. NI-DAQmx performs a timeout check only if the method
must wait before it writes data. This method returns an error if the time elapses. The default timeout is 10 seconds. If you set timeout to nidaqmx.constants.WAIT_INFINITELY,
the method waits indefinitely. If you set timeout to 0, the method tries once to write the

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class nidaqmx.stream_writers.CounterWriter(task_out_stream, auto_start=)
Bases: nidaqmx.stream_writers.ChannelWriterBase
Writes samples to a counter output channel in an NI-DAQmx task.
auto_start
bool – Specifies if the write method automatically starts the task if you did not explicitly start it with the
DAQmx Start Task method.
If you do not specify a value for this parameter, NI-DAQmx determines its value based on the type of write
method used. If you use a one sample write method, its value is True; conversely, if you use a many sample
write method, its value is False.
verify_array_shape
bool – Indicates whether the size and shape of the user-defined NumPy arrays passed to read methods are
verified. Defaults to True when this object is instantiated.
Setting this property to True may marginally adversely impact the performance of read methods.
write_many_sample_pulse_frequency(frequencies, duty_cycles, timeout=10.0)
Writes one or more pulse samples in terms of frequency to a single counter output channel in a task.
If the task uses on-demand timing, this method returns only after the device generates all samples. Ondemand is the default timing type if you do not use the timing property on the task to configure a sample
timing type. If the task uses any timing type other than on-demand, this method returns immediately and
does not wait for the device to generate all samples. Your application must determine if the task is done to
ensure that the device generated all samples.
Parameters
• frequencies (numpy.ndarray) – Contains a 1D NumPy array of floating-point
values that holds the frequency portion of the pulse samples to write to the task. Each
element of the array corresponds to a sample to write.
• duty_cycles (numpy.ndarray) – Contains a 1D NumPy array of floating-point
values that holds the duty cycle portion of the pulse samples to write to the task. Each
element of the array corresponds to a sample to write.
• timeout (Optional[float]) – Specifies the amount of time in seconds to wait for
the method to write all samples. NI-DAQmx performs a timeout check only if the method
must wait before it writes data. This method returns an error if the time elapses. The default timeout is 10 seconds. If you set timeout to nidaqmx.constants.WAIT_INFINITELY,
the method waits indefinitely. If you set timeout to 0, the method tries once to write the
submitted samples. If the method could not write all the submitted samples, it returns an
error and the number of samples successfully written.
Returns Specifies the actual number of samples this method successfully wrote.
Return type int
write_many_sample_pulse_ticks(high_ticks, low_ticks, timeout=10.0)
Writes one or more pulse samples in terms of ticks to a single counter output channel in a task.

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If the task uses on-demand timing, this method returns only after the device generates all samples. Ondemand is the default timing type if you do not use the timing property on the task to configure a sample
timing type. If the task uses any timing type other than on-demand, this method returns immediately and
does not wait for the device to generate all samples. Your application must determine if the task is done to
ensure that the device generated all samples.
Parameters
• high_ticks (numpy.ndarray) – Contains a 1D NumPy array of 32-bit unsigned
integer values that holds the high ticks portion of the pulse samples to write to the task.
Each element of the array corresponds to a sample to write.
• low_ticks (numpy.ndarray) – Contains a 1D NumPy array of 32-bit unsigned integer values that holds the low ticks portion of the pulse samples to write to the task. Each
element of the array corresponds to a sample to write.
• timeout (Optional[float]) – Specifies the amount of time in seconds to wait for
the method to write all samples. NI-DAQmx performs a timeout check only if the method
must wait before it writes data. This method returns an error if the time elapses. The default timeout is 10 seconds. If you set timeout to nidaqmx.constants.WAIT_INFINITELY,
the method waits indefinitely. If you set timeout to 0, the method tries once to write the
submitted samples. If the method could not write all the submitted samples, it returns an
error and the number of samples successfully written.
Returns Specifies the actual number of samples this method successfully wrote.
Return type int
write_many_sample_pulse_time(high_times, low_times, timeout=10.0)
Writes one or more pulse samples in terms of time to a single counter output channel in a task.
If the task uses on-demand timing, this method returns only after the device generates all samples. Ondemand is the default timing type if you do not use the timing property on the task to configure a sample
timing type. If the task uses any timing type other than on-demand, this method returns immediately and
does not wait for the device to generate all samples. Your application must determine if the task is done to
ensure that the device generated all samples.
Parameters
• high_times (numpy.ndarray) – Contains a 1D NumPy array of floating-point values that holds the high time portion of the pulse samples to write to the task. Each element
of the array corresponds to a sample to write.
• low_times (numpy.ndarray) – Contains a 1D NumPy array of floating-point values
that holds the low time portion of the pulse samples to write to the task. Each element of
the array corresponds to a sample to write.
• timeout (Optional[float]) – Specifies the amount of time in seconds to wait for
the method to write all samples. NI-DAQmx performs a timeout check only if the method
must wait before it writes data. This method returns an error if the time elapses. The default timeout is 10 seconds. If you set timeout to nidaqmx.constants.WAIT_INFINITELY,
the method waits indefinitely. If you set timeout to 0, the method tries once to write the
submitted samples. If the method could not write all the submitted samples, it returns an
error and the number of samples successfully written.
Returns Specifies the actual number of samples this method successfully wrote.
Return type int
write_one_sample_pulse_frequency(frequency, duty_cycle, timeout=10)
Writes a new pulse frequency and duty cycle to a single counter output channel in a task.

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Parameters
• frequency (float) – Specifies at what frequency to generate pulses.
• duty_cycle (float) – Specifies the width of the pulse divided by the pulse period.
NI-DAQmx uses this ratio combined with frequency to determine pulse width and the
interval between pulses.
• auto_start (Optional[bool]) – Specifies if this method automatically starts the
task if you did not explicitly start it with the DAQmx Start Task method.
• timeout (Optional[float]) – Specifies the amount of time in seconds to wait for
the method to write all samples. NI-DAQmx performs a timeout check only if the method
must wait before it writes data. This method returns an error if the time elapses. The default timeout is 10 seconds. If you set timeout to nidaqmx.constants.WAIT_INFINITELY,
the method waits indefinitely. If you set timeout to 0, the method tries once to write the
submitted samples. If the method could not write all the submitted samples, it returns an
error and the number of samples successfully written.
write_one_sample_pulse_ticks(high_ticks, low_ticks, timeout=10)
Writes a new pulse high tick count and low tick count to a single counter output channel in a task.
Parameters
• high_ticks (float) – Specifies the number of ticks the pulse is high.
• low_ticks (float) – Specifies the number of ticks the pulse is low.
• timeout (Optional[float]) – Specifies the amount of time in seconds to wait for
the method to write all samples. NI-DAQmx performs a timeout check only if the method
must wait before it writes data. This method returns an error if the time elapses. The default timeout is 10 seconds. If you set timeout to nidaqmx.constants.WAIT_INFINITELY,
the method waits indefinitely. If you set timeout to 0, the method tries once to write the
submitted samples. If the method could not write all the submitted samples, it returns an
error and the number of samples successfully written.
write_one_sample_pulse_time(high_time, low_time, timeout=10)
Writes a new pulse high time and low time to a single counter output channel in a task.
Parameters
• high_time (float) – Specifies the amount of time the pulse is high.
• low_time (float) – Specifies the amount of time the pulse is low.
• timeout (Optional[float]) – Specifies the amount of time in seconds to wait for
the method to write all samples. NI-DAQmx performs a timeout check only if the method
must wait before it writes data. This method returns an error if the time elapses. The default timeout is 10 seconds. If you set timeout to nidaqmx.constants.WAIT_INFINITELY,
the method waits indefinitely. If you set timeout to 0, the method tries once to write the
submitted samples. If the method could not write all the submitted samples, it returns an
error and the number of samples successfully written.

class nidaqmx.stream_writers.DigitalSingleChannelWriter(task_out_stream,
auto_start=)
Bases: nidaqmx.stream_writers.ChannelWriterBase
Writes samples to a single digital output channel in an NI-DAQmx task.
auto_start
bool – Specifies if the write method automatically starts the task if you did not explicitly start it with the
DAQmx Start Task method.
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If you do not specify a value for this parameter, NI-DAQmx determines its value based on the type of write
method used. If you use a one sample write method, its value is True; conversely, if you use a many sample
write method, its value is False.
verify_array_shape
bool – Indicates whether the size and shape of the user-defined NumPy arrays passed to read methods are
verified. Defaults to True when this object is instantiated.
Setting this property to True may marginally adversely impact the performance of read methods.
write_many_sample_port_byte(data, timeout=10.0)
Writes one or more 8-bit unsigned integer samples to a single digital output channel in a task.
Use this method for devices with up to 8 lines per port.
If the task uses on-demand timing, this method returns only after the device generates all samples. Ondemand is the default timing type if you do not use the timing property on the task to configure a sample
timing type. If the task uses any timing type other than on-demand, this method returns immediately and
does not wait for the device to generate all samples. Your application must determine if the task is done to
ensure that the device generated all samples.
Parameters
• data (numpy.ndarray) – Contains a 1D NumPy array of 8-bit unsigned integer samples to write to the task. Each element of the array corresponds to a sample to write.
• timeout (Optional[float]) – Specifies the amount of time in seconds to wait for
the method to write all samples. NI-DAQmx performs a timeout check only if the method
must wait before it writes data. This method returns an error if the time elapses. The default timeout is 10 seconds. If you set timeout to nidaqmx.constants.WAIT_INFINITELY,
the method waits indefinitely. If you set timeout to 0, the method tries once to write the
submitted samples. If the method could not write all the submitted samples, it returns an
error and the number of samples successfully written.
Returns Specifies the actual number of samples this method successfully wrote.
Return type int
write_many_sample_port_uint16(data, timeout=10.0)
Writes one or more 16-bit unsigned integer samples to a single digital output channel in a task.
Use this method for devices with up to 16 lines per port.
If the task uses on-demand timing, this method returns only after the device generates all samples. Ondemand is the default timing type if you do not use the timing property on the task to configure a sample
timing type. If the task uses any timing type other than on-demand, this method returns immediately and
does not wait for the device to generate all samples. Your application must determine if the task is done to
ensure that the device generated all samples.
Parameters
• data (numpy.ndarray) – Contains a 1D NumPy array of 16-bit unsigned integer samples to write to the task. Each element of the array corresponds to a sample to write.
• timeout (Optional[float]) – Specifies the amount of time in seconds to wait for
the method to write all samples. NI-DAQmx performs a timeout check only if the method
must wait before it writes data. This method returns an error if the time elapses. The default timeout is 10 seconds. If you set timeout to nidaqmx.constants.WAIT_INFINITELY,
the method waits indefinitely. If you set timeout to 0, the method tries once to write the
submitted samples. If the method could not write all the submitted samples, it returns an
error and the number of samples successfully written.

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Returns Specifies the actual number of samples this method successfully wrote.
Return type int
write_many_sample_port_uint32(data, timeout=10.0)
Writes one or more 32-bit unsigned integer samples to a single digital output channel in a task.
Use this method for devices with up to 32 lines per port.
If the task uses on-demand timing, this method returns only after the device generates all samples. Ondemand is the default timing type if you do not use the timing property on the task to configure a sample
timing type. If the task uses any timing type other than on-demand, this method returns immediately and
does not wait for the device to generate all samples. Your application must determine if the task is done to
ensure that the device generated all samples.
Parameters
• data (numpy.ndarray) – Contains a 1D NumPy array of 32-bit unsigned integer samples to write to the task. Each element of the array corresponds to a sample to write.
• timeout (Optional[float]) – Specifies the amount of time in seconds to wait for
the method to write all samples. NI-DAQmx performs a timeout check only if the method
must wait before it writes data. This method returns an error if the time elapses. The default timeout is 10 seconds. If you set timeout to nidaqmx.constants.WAIT_INFINITELY,
the method waits indefinitely. If you set timeout to 0, the method tries once to write the
submitted samples. If the method could not write all the submitted samples, it returns an
error and the number of samples successfully written.
Returns Specifies the actual number of samples this method successfully wrote.
Return type int
write_one_sample_multi_line(data, timeout=10)
Writes a single boolean sample to a single digital output channel in a task. The channel can contain
multiple digital lines.
Parameters
• data (numpy.ndarray) – Contains a 1D NumPy array of boolean samples to write to
the task. Each element of the array corresponds to a line in the channel.
• timeout (Optional[float]) – Specifies the amount of time in seconds to wait for
the method to write all samples. NI-DAQmx performs a timeout check only if the method
must wait before it writes data. This method returns an error if the time elapses. The default timeout is 10 seconds. If you set timeout to nidaqmx.constants.WAIT_INFINITELY,
the method waits indefinitely. If you set timeout to 0, the method tries once to write the
submitted samples. If the method could not write all the submitted samples, it returns an
error and the number of samples successfully written.
write_one_sample_one_line(data, timeout=10)
Writes a single boolean sample to a single digital output channel in a task. The channel can contain only
one digital line.
Parameters
• data (int) – Specifies the boolean sample to write to the task.
• timeout (Optional[float]) – Specifies the amount of time in seconds to wait for
the method to write all samples. NI-DAQmx performs a timeout check only if the method
must wait before it writes data. This method returns an error if the time elapses. The default timeout is 10 seconds. If you set timeout to nidaqmx.constants.WAIT_INFINITELY,
the method waits indefinitely. If you set timeout to 0, the method tries once to write the

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submitted samples. If the method could not write all the submitted samples, it returns an
error and the number of samples successfully written.
write_one_sample_port_byte(data, timeout=10)
Writes a single 8-bit unsigned integer sample to a single digital output channel in a task.
Use this method for devices with up to 8 lines per port.
Parameters
• data (int) – Specifies the 8-bit unsigned integer sample to write to the task.
• timeout (Optional[float]) – Specifies the amount of time in seconds to wait for
the method to write all samples. NI-DAQmx performs a timeout check only if the method
must wait before it writes data. This method returns an error if the time elapses. The default timeout is 10 seconds. If you set timeout to nidaqmx.constants.WAIT_INFINITELY,
the method waits indefinitely. If you set timeout to 0, the method tries once to write the
submitted samples. If the method could not write all the submitted samples, it returns an
error and the number of samples successfully written.
write_one_sample_port_uint16(data, timeout=10)
Writes a single 16-bit unsigned integer sample to a single digital output channel in a task.
Use this method for devices with up to 16 lines per port.
Parameters
• data (int) – Specifies the 16-bit unsigned integer sample to write to the task.
• timeout (Optional[float]) – Specifies the amount of time in seconds to wait for
the method to write all samples. NI-DAQmx performs a timeout check only if the method
must wait before it writes data. This method returns an error if the time elapses. The default timeout is 10 seconds. If you set timeout to nidaqmx.constants.WAIT_INFINITELY,
the method waits indefinitely. If you set timeout to 0, the method tries once to write the
submitted samples. If the method could not write all the submitted samples, it returns an
error and the number of samples successfully written.
write_one_sample_port_uint32(data, timeout=10)
Writes a single 32-bit unsigned integer sample to a single digital output channel in a task.
Use this method for devices with up to 32 lines per port.
Parameters
• data (int) – Specifies the 32-bit unsigned integer sample to write to the task.
• timeout (Optional[float]) – Specifies the amount of time in seconds to wait for
the method to write all samples. NI-DAQmx performs a timeout check only if the method
must wait before it writes data. This method returns an error if the time elapses. The default timeout is 10 seconds. If you set timeout to nidaqmx.constants.WAIT_INFINITELY,
the method waits indefinitely. If you set timeout to 0, the method tries once to write the
submitted samples. If the method could not write all the submitted samples, it returns an
error and the number of samples successfully written.

class nidaqmx.stream_writers.DigitalMultiChannelWriter(task_out_stream,
auto_start=)
Bases: nidaqmx.stream_writers.ChannelWriterBase
Writes samples to one or more digital output channels in an NI-DAQmx task.

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auto_start
bool – Specifies if the write method automatically starts the task if you did not explicitly start it with the
DAQmx Start Task method.
If you do not specify a value for this parameter, NI-DAQmx determines its value based on the type of write
method used. If you use a one sample write method, its value is True; conversely, if you use a many sample
write method, its value is False.
verify_array_shape
bool – Indicates whether the size and shape of the user-defined NumPy arrays passed to read methods are
verified. Defaults to True when this object is instantiated.
Setting this property to True may marginally adversely impact the performance of read methods.
write_many_sample_port_byte(data, timeout=10.0)
Writes one or more 8-bit unsigned integer samples to one or more digital output channels in a task.
Use this method for devices with up to 8 lines per port.
If the task uses on-demand timing, this method returns only after the device generates all samples. Ondemand is the default timing type if you do not use the timing property on the task to configure a sample
timing type. If the task uses any timing type other than on-demand, this method returns immediately and
does not wait for the device to generate all samples. Your application must determine if the task is done to
ensure that the device generated all samples.
Parameters
• data (numpy.ndarray) – Contains a 2D NumPy array of 8-bit unsigned integer samples to write to the task.
Each row corresponds to a channel in the task. Each column corresponds to a sample to
write to each channel. The order of the channels in the array corresponds to the order in
which you add the channels to the task.
• timeout (Optional[float]) – Specifies the amount of time in seconds to wait for
the method to write all samples. NI-DAQmx performs a timeout check only if the method
must wait before it writes data. This method returns an error if the time elapses. The default timeout is 10 seconds. If you set timeout to nidaqmx.constants.WAIT_INFINITELY,
the method waits indefinitely. If you set timeout to 0, the method tries once to write the
submitted samples. If the method could not write all the submitted samples, it returns an
error and the number of samples successfully written.
Returns Specifies the actual number of samples this method successfully wrote to each channel
in the task.
Return type int
write_many_sample_port_uint16(data, timeout=10.0)
Writes one or more 16-bit unsigned integer samples to one or more digital output channels in a task.
Use this method for devices with up to 16 lines per port.
If the task uses on-demand timing, this method returns only after the device generates all samples. Ondemand is the default timing type if you do not use the timing property on the task to configure a sample
timing type. If the task uses any timing type other than on-demand, this method returns immediately and
does not wait for the device to generate all samples. Your application must determine if the task is done to
ensure that the device generated all samples.
Parameters
• data (numpy.ndarray) – Contains a 2D NumPy array of 16-bit unsigned integer samples to write to the task.

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Each row corresponds to a channel in the task. Each column corresponds to a sample to
write to each channel. The order of the channels in the array corresponds to the order in
which you add the channels to the task.
• timeout (Optional[float]) – Specifies the amount of time in seconds to wait for
the method to write all samples. NI-DAQmx performs a timeout check only if the method
must wait before it writes data. This method returns an error if the time elapses. The default timeout is 10 seconds. If you set timeout to nidaqmx.constants.WAIT_INFINITELY,
the method waits indefinitely. If you set timeout to 0, the method tries once to write the
submitted samples. If the method could not write all the submitted samples, it returns an
error and the number of samples successfully written.
Returns Specifies the actual number of samples this method successfully wrote to each channel
in the task.
Return type int
write_many_sample_port_uint32(data, timeout=10.0)
Writes one or more 32-bit unsigned integer samples to one or more digital output channels in a task.
Use this method for devices with up to 32 lines per port.
If the task uses on-demand timing, this method returns only after the device generates all samples. Ondemand is the default timing type if you do not use the timing property on the task to configure a sample
timing type. If the task uses any timing type other than on-demand, this method returns immediately and
does not wait for the device to generate all samples. Your application must determine if the task is done to
ensure that the device generated all samples.
Parameters
• data (numpy.ndarray) – Contains a 2D NumPy array of 32-bit unsigned integer samples to write to the task.
Each row corresponds to a channel in the task. Each column corresponds to a sample to
write to each channel. The order of the channels in the array corresponds to the order in
which you add the channels to the task.
• timeout (Optional[float]) – Specifies the amount of time in seconds to wait for
the method to write all samples. NI-DAQmx performs a timeout check only if the method
must wait before it writes data. This method returns an error if the time elapses. The default timeout is 10 seconds. If you set timeout to nidaqmx.constants.WAIT_INFINITELY,
the method waits indefinitely. If you set timeout to 0, the method tries once to write the
submitted samples. If the method could not write all the submitted samples, it returns an
error and the number of samples successfully written.
Returns Specifies the actual number of samples this method successfully wrote to each channel
in the task.
Return type int
write_one_sample_multi_line(data, timeout=10)
Writes a single boolean sample to one or more digital output channels in a task. The channel can contain
multiple digital lines.
Parameters
• data (numpy.ndarray) – Contains a 2D NumPy array of boolean samples to write to
the task.
Each row corresponds to a channel in the task. Each column corresponds to a line from
each channel. The order of the channels in the array corresponds to the order in which you
add the channels to the task.

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• timeout (Optional[float]) – Specifies the amount of time in seconds to wait for
the method to write all samples. NI-DAQmx performs a timeout check only if the method
must wait before it writes data. This method returns an error if the time elapses. The default timeout is 10 seconds. If you set timeout to nidaqmx.constants.WAIT_INFINITELY,
the method waits indefinitely. If you set timeout to 0, the method tries once to write the
submitted samples. If the method could not write all the submitted samples, it returns an
error and the number of samples successfully written.
write_one_sample_one_line(data, timeout=10)
Writes a single boolean sample to one or more digital output channels in a task. The channel can contain
only one digital line.
Parameters
• data (numpy.ndarray) – Contains a 1D NumPy array of boolean samples to write to
the task.
Each element in the array corresponds to a channel in the task. The order of the channels
in the array corresponds to the order in which you add the channels to the task.
• timeout (Optional[float]) – Specifies the amount of time in seconds to wait for
the method to write all samples. NI-DAQmx performs a timeout check only if the method
must wait before it writes data. This method returns an error if the time elapses. The default timeout is 10 seconds. If you set timeout to nidaqmx.constants.WAIT_INFINITELY,
the method waits indefinitely. If you set timeout to 0, the method tries once to write the
submitted samples. If the method could not write all the submitted samples, it returns an
error and the number of samples successfully written.
write_one_sample_port_byte(data, timeout=10)
Writes a single 8-bit unsigned integer sample to one or more digital output channels in a task.
Use this method for devices with up to 8 lines per port.
Parameters
• data (numpy.ndarray) – Contains a 1D NumPy array of 8-bit unsigned integer samples to write to the task.
Each element in the array corresponds to a channel in the task. The order of the channels
in the array corresponds to the order in which you add the channels to the task.
• timeout (Optional[float]) – Specifies the amount of time in seconds to wait for
the method to write all samples. NI-DAQmx performs a timeout check only if the method
must wait before it writes data. This method returns an error if the time elapses. The default timeout is 10 seconds. If you set timeout to nidaqmx.constants.WAIT_INFINITELY,
the method waits indefinitely. If you set timeout to 0, the method tries once to write the
submitted samples. If the method could not write all the submitted samples, it returns an
error and the number of samples successfully written.
write_one_sample_port_uint16(data, timeout=10)
Writes a single 16-bit unsigned integer sample to one or more digital output channels in a task.
Use this method for devices with up to 16 lines per port.
Parameters
• data (numpy.ndarray) – Contains a 1D NumPy array of 16-bit unsigned integer samples to write to the task.
Each element in the array corresponds to a channel in the task. The order of the channels
in the array corresponds to the order in which you add the channels to the task.

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nidaqmx.system
class nidaqmx.system.system.System
Bases: object
Represents a DAQmx system.
Contains static properties that access tasks, scales, and global channels stored in Measurement Automation
Explorer (MAX), performs immediate operations on DAQ hardware, and creates classes from which you can
get information about the hardware.
add_cdaq_sync_connection(ports_to_connect)
Adds a cDAQ Sync connection between devices. The connection is not verified.
Parameters ports_to_connect (nidaqmx.types.CDAQSyncConnection) – Specifies the cDAQ Sync ports to connect.
are_configured_cdaq_sync_ports_disconnected(chassis_devices_ports=u’‘, timeout=1.0)
Verifies configured cDAQ Sync connections between devices. Failures generally indicate a wiring issue or
that a device has been powered off or removed. Stop all NI-DAQmx tasks running on the devices prior to
running this function because any running tasks cause the verification process to fail.
Parameters
• chassis_devices_ports (Optional[str]) – Specifies the names of the CompactDAQ chassis, C Series modules, or cDAQ Sync ports in comma separated form to
search. If no names are specified, all cDAQ Sync ports on connected, non-simulated devices are scanned.

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• timeout (Optional[float]) – Specifies the time in seconds to wait for the device
to respond before timing out.
Returns Returns the port-to-port connections that failed verification.
Return type List[nidaqmx.types.CDAQSyncConnection]
auto_configure_cdaq_sync_connections(chassis_devices_ports=u’‘, timeout=-1.0)
Detects and configures cDAQ Sync connections between devices. Stop all NI-DAQmx tasks running on
the devices prior to running this function because any running tasks cause auto-configuration to fail.
Parameters
• chassis_devices_ports (Optional[str]) – Specifies the names of the CompactDAQ chassis, C Series modules, or cDAQ Sync ports in comma separated form to
search. If no names are specified, all cDAQ Sync ports on connected, non-simulated devices are scanned.
• timeout (Optional[float]) – Specifies the time in seconds to wait for the device
to respond before timing out. If a timeout occurs, no configuration is changed.
Returns Returns the configured port-to-port connections.
Return type List[nidaqmx.types.CDAQSyncConnection]

connect_terms(source_terminal, destination_terminal, signal_modifiers=)
Creates a route between a source and destination terminal. The route can carry a variety of digital signals,
such as triggers, clocks, and hardware events.
Parameters
• source_terminal (str) – Specifies the originating terminal of the route. A DAQmx
terminal constant lists all terminals available on devices installed in the system. You also
can specify a source terminal by specifying a string that contains a terminal name.
• destination_terminal (str) – Specifies the receiving terminal of the route. A
DAQmx terminal constant provides a list of all terminals available on devices installed in
the system. You also can specify a destination terminal by specifying a string that contains
a terminal name.
• signal_modifiers
(Optional[nidaqmx.constants.
SignalModifiers]) – Specifies whether to invert the signal this function routes from
the source terminal to the destination terminal.
devices
nidaqmx.system._collections.DeviceCollection – Indicates the collection of devices for this DAQmx system.
disconnect_terms(source_terminal, destination_terminal)
Removes signal routes you created by using the DAQmx Connect Terminals function. The DAQmx Disconnect Terminals function cannot remove task-based routes, such as those you create through timing and
triggering configuration.
Parameters
• source_terminal (str) – Specifies the originating terminal of the route. A DAQmx
terminal constant lists all terminals available on devices installed in the system. You also
can specify a source terminal by specifying a string that contains a terminal name.
• destination_terminal (str) – Specifies the receiving terminal of the route. A
DAQmx terminal constant provides a list of all terminals available on devices installed in

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the system. You also can specify a destination terminal by specifying a string that contains
a terminal name.
driver_version
collections.namedtuple – Indicates the major, minor and update portions of the installed version of NIDAQmx.
•major_version (int): Indicates the major portion of the installed version of NI-DAQmx, such as 7 for
version 7.0.
•minor_version (int): Indicates the minor portion of the installed version of NI-DAQmx, such as 0 for
version 7.0.
•update_version (int): Indicates the update portion of the installed version of NI-DAQmx, such as 1
for version 9.0.1.
get_analog_power_up_states(device_name)
Gets the power up states for analog physical channels.
Parameters device_name (str) – Specifies the name as configured in MAX of the device
to which this operation applies.
Returns
Contains the physical channels and power up states set. Each element of the list contains a
physical channel and the power up state set for that physical channel.
• physical_channel (str): Specifies the physical channel that was modified.
• power_up_state (float): Specifies the power up state set for the physical channel specified
with the physical_channel input.
• channel_type (nidaqmx.constants.AOPowerUpOutputBehavior): Specifies
the output type for the physical channel specified with the physical_channel input.
Return type power_up_states (List[nidaqmx.types.AOPowerUpState])
get_analog_power_up_states_with_output_type(physical_channels)
Gets the power up states for analog physical channels.
Parameters physical_channels (List[str]) – Indicates the physical channels that
were modified.
Returns
Contains the physical channels and power up states set. Each element of the list contains a
physical channel and the power up state set for that physical channel.
• physical_channel (str): Specifies the physical channel that was modified.
• power_up_state (float): Specifies the power up state set for the physical channel specified
with the physical_channel input.
• channel_type (nidaqmx.constants.AOPowerUpOutputBehavior): Specifies
the output type for the physical channel specified with the physical_channel input.
Return type power_up_states (List[nidaqmx.types.AOPowerUpState])
get_digital_logic_family_power_up_state(device_name)
Gets the digital logic family for a device.
Parameters device_name (str) – Specifies the name as configured in MAX of the device
to which this operation applies.

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Returns Specifies the logic family to set the device to when it powers up. A logic family corresponds to voltage thresholds that are compatible with a group of voltage standards. Refer
to device documentation for information on the logic high and logic low voltages for these
logic families.
Return type nidaqmx.constants.LogicFamily
get_digital_power_up_states(device_name)
Gets the power up states for digital physical lines.
Parameters device_name (str) – Specifies the name as configured in MAX of the device
to which this operation applies.
Returns
Contains the physical channels and power up states set. Each element of the list contains a
physical channel and the power up state set for that physical channel.
• physical_channel (str): Indicates the physical channel that was modified.
• power_up_state (nidaqmx.constants.PowerUpStates): Indicates the power up
state set for the physical channel specified with the physical_channel output.
Return type List[nidaqmx.types.DOPowerUpState]
get_digital_pull_up_pull_down_states(device_name)
Gets the resistor level for lines when they are in tristate logic.
Parameters device_name (str) – Specifies the name as configured in MAX of the device
to which this operation applies.
Returns
Contains the physical channels and power up states set. Each element of the list contains a
physical channel and the power up state set for that physical channel.
• physical_channel (str): Indicates the physical channel that was modified.
• power_up_state (nidaqmx.constants.ResistorState): Indicates the power up
state set for the physical channel specified with the physical_channel output.
Return type List[nidaqmx.types.DOResistorPowerUpState]
global_channels
nidaqmx.system._collections.PersistedChannelCollection – Indicates the collection of global channels for
this DAQmx system.
static local()
nidaqmx.system.system.System: Represents the local DAQmx system.
remove_cdaq_sync_connection(ports_to_disconnect)
Removes a cDAQ Sync connection between devices. The connection is not verified.
Parameters ports_to_disconnect (nidaqmx.types.CDAQSyncConnection) –
Specifies the cDAQ Sync ports to disconnect.
scales
nidaqmx.system._collections.PersistedScaleCollection – Indicates the collection of custom scales for this
DAQmx system.
set_analog_power_up_states(device_name, power_up_states)
Updates power up states for analog physical channels.
Parameters

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• device_name (str) – Specifies the name as configured in MAX of the device to which
this operation applies.
• power_up_states (List[nidaqmx.types.AOPowerUpState]) – Contains
the physical channels and power up states to set. Each element of the list contains a
physical channel and the power up state to set for that physical channel.
– physical_channel (str): Specifies the physical channel to modify.
– power_up_state (float): Specifies the power up state to set for the physical channel
specified with the physical_channel input.
– channel_type (nidaqmx.constants.AOPowerUpOutputBehavior): Specifies the output type for the physical channel specified with the physical_channel input.
set_analog_power_up_states_with_output_type(power_up_states)
Updates power up states for analog physical channels.
Parameters power_up_states (List[nidaqmx.types.AOPowerUpState]) –
Contains the physical channels and power up states to set. Each element of the list contains
a physical channel and the power up state to set for that physical channel.
• physical_channel (str): Specifies the physical channel to modify.
• power_up_state (float): Specifies the power up state to set for the physical channel specified with the physical_channel input.
• channel_type (nidaqmx.constants.AOPowerUpOutputBehavior): Specifies
the output type for the physical channel specified with the physical_channel input.
set_digital_logic_family_power_up_state(device_name, logic_family)
Sets the digital logic family to use when the device powers up.
Parameters
• device_name (str) – Specifies the name as configured in MAX of the device to which
this operation applies.
• logic_family (nidaqmx.constants.LogicFamily) – Specifies the logic family set to the device to when it powers up. A logic family corresponds to voltage thresholds
that are compatible with a group of voltage standards. Refer to device documentation for
information on the logic high and logic low voltages for these logic families.
set_digital_power_up_states(device_name, power_up_states)
Updates power up states for digital physical channels.
Parameters
• device_name (str) – Specifies the name as configured in MAX of the device to which
this operation applies.
• power_up_states (List[nidaqmx.types.DOPowerUpState]) – Contains
the physical channels and power up states to set. Each element of the list contains a
physical channel and the power up state to set for that physical channel.
– physical_channel (str): Specifies the digital line or port to modify. You cannot modify
dedicated digital input lines.
– power_up_state (nidaqmx.constants.PowerUpStates): Specifies the power
up state to set for the physical channel specified with the physical_channel input.
set_digital_pull_up_pull_down_states(device_name, power_up_states)
Sets the resistor level to pull up or pull down for lines when they are in tristate logic.

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Parameters
• device_name (str) – Specifies the name as configured in MAX of the device to which
this operation applies.
• power_up_states (List[nidaqmx.types.DOResistorPowerUpState]) –
Contains the physical channels and power up states to set. Each element of the list contains
a physical channel and the power up state to set for that physical channel.
– physical_channel (str): Specifies the digital line or port to modify. You cannot modify
dedicated digital input lines.
– power_up_state (nidaqmx.constants.ResistorState): Specifies the power
up state to set for the physical channel specified with the physical_channel input.
tasks
nidaqmx.system._collections.PersistedTaskCollection – Indicates the collection of saved tasks for this
DAQmx system.
tristate_output_term(output_terminal)
Sets a terminal to high-impedance state. If you connect an external signal to a terminal on the I/O connector, the terminal must be in high-impedance state. Otherwise, the device could double-drive the terminal
and damage the hardware. If you use this function on a terminal in an active route, the function fails and
returns an error.
Parameters output_terminal (str) – Specifies the terminal on the I/O connector to set to
high-impedance state. A DAQmx terminal constant lists all available terminals on installed
devices. You also can specify an output terminal by using a string that contains a terminal
name.

nidaqmx.system.collections
nidaqmx.system.device_collection
class nidaqmx.system._collections.device_collection.DeviceCollection
Bases: _abcoll.Sequence
Contains the collection of devices for a DAQmx system.
This class defines methods that implements a container object.
device_names
List[str] – Indicates the names of all devices on this device collection.
nidaqmx.system.persisted_channel_collection
class nidaqmx.system._collections.persisted_channel_collection.PersistedChannelCollection
Bases: _abcoll.Sequence
Contains the collection of global channels for a DAQmx system.
This class defines methods that implements a container object.
global_channel_names
List[str] – The names of all the global channels on this collection.

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nidaqmx.system.persisted_scale_collection
class nidaqmx.system._collections.persisted_scale_collection.PersistedScaleCollection
Bases: _abcoll.Sequence
Contains the collection of custom scales on a DAQmx system.
This class defines methods that implements a container object.
scale_names
List[str] – Indicates the names of all the custom scales on this collection.
nidaqmx.system.persisted_task_collection
class nidaqmx.system._collections.persisted_task_collection.PersistedTaskCollection
Bases: _abcoll.Sequence
Contains the collection of task saved on a DAQmx system.
This class defines methods that implements a container object.
task_names
List[str] – Indicates the names of all the tasks on this collection.
nidaqmx.system.physical_channel_collection

class nidaqmx.system._collections.physical_channel_collection.AIPhysicalChannelCollection(devi
Bases:
nidaqmx.system._collections.physical_channel_collection.
PhysicalChannelCollection
Contains the collection of analog input physical channels for a DAQmx device.
This class defines methods that implements a container object.

class nidaqmx.system._collections.physical_channel_collection.AOPhysicalChannelCollection(devi
Bases:
nidaqmx.system._collections.physical_channel_collection.
PhysicalChannelCollection
Contains the collection of analog output physical channels for a DAQmx device.
This class defines methods that implements a container object.

class nidaqmx.system._collections.physical_channel_collection.CIPhysicalChannelCollection(devi
Bases:
nidaqmx.system._collections.physical_channel_collection.
PhysicalChannelCollection
Contains the collection of counter input physical channels for a DAQmx device.
This class defines methods that implements a container object.

class nidaqmx.system._collections.physical_channel_collection.COPhysicalChannelCollection(devi
Bases:
nidaqmx.system._collections.physical_channel_collection.
PhysicalChannelCollection
Contains the collection of counter output physical channels for a DAQmx device.
This class defines methods that implements a container object.
class nidaqmx.system._collections.physical_channel_collection.DILinesCollection(device_name)
Bases:
nidaqmx.system._collections.physical_channel_collection.
PhysicalChannelCollection

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Contains the collection of digital input lines for a DAQmx device.
This class defines methods that implements a container object.
class nidaqmx.system._collections.physical_channel_collection.DIPortsCollection(device_name)
Bases:
nidaqmx.system._collections.physical_channel_collection.
PhysicalChannelCollection
Contains the collection of digital input ports for a DAQmx device.
This class defines methods that implements a container object.
class nidaqmx.system._collections.physical_channel_collection.DOLinesCollection(device_name)
Bases:
nidaqmx.system._collections.physical_channel_collection.
PhysicalChannelCollection
Contains the collection of digital output lines for a DAQmx device.
This class defines methods that implements a container object.
class nidaqmx.system._collections.physical_channel_collection.DOPortsCollection(device_name)
Bases:
nidaqmx.system._collections.physical_channel_collection.
PhysicalChannelCollection
Contains the collection of digital output ports for a DAQmx device.
This class defines methods that implements a container object.

class nidaqmx.system._collections.physical_channel_collection.PhysicalChannelCollection(device_
Bases: _abcoll.Sequence
Contains the collection of physical channels for a DAQmx device.
This class defines methods that implements a container object.
all
nidaqmx.system.physical_channel.PhysicalChannel – Specifies a physical channel object that represents
the entire list of physical channels on this channel collection.
channel_names
List[str] – Specifies the entire list of physical channels on this collection.

nidaqmx.system.device
class nidaqmx.system.device.Device(name)
Bases: object
Represents a DAQmx device.
__init__(name)
Parameters name (str) – Specifies the name of the device.
__weakref__
list of weak references to the object (if defined)
accessory_product_nums
List[int] – Indicates the unique hardware identification number for accessories connected to the device.
Each list element corresponds to a connector. For example, index 0 corresponds to connector 0. The list
contains 0 for each connector with no accessory connected.
accessory_product_types
List[str] – Indicates the model names of accessories connected to the device. Each list element corresponds

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to a connector. For example, index 0 corresponds to connector 0. The list contains an empty string for
each connector with no accessory connected.
accessory_serial_nums
List[int] – Indicates the serial number for accessories connected to the device. Each list element corresponds to a connector. For example, index 0 corresponds to connector 0. The list contains 0 for each
connector with no accessory connected.
static add_network_device(ip_address, device_name=u’‘, attempt_reservation=False,
out=10.0)
Adds a Network cDAQ device to the system and, if specified, attempts to reserve it.

time-

Parameters
• ip_address (str) – Specifies the string containing the IP address (in dotted decimal
notation) or hostname of the device to add to the system.
• device_name (Optional[str]) – Indicates the name to assign to the device. If
unspecified, NI-DAQmx chooses the device name.
• attempt_reservation (Optional[bool]) – Indicates if a reservation should be
attempted after the device is successfully added. By default, this parameter is set to False.
• timeout (Optional[float]) – Specifies the time in seconds to wait for the device
to respond before timing out.
Returns Specifies the object that represents the device this operation applied to.
Return type nidaqmx.system.device.Device
ai_bridge_rngs
List[float] – Indicates pairs of input voltage ratio ranges, in volts per volt, supported by devices that acquire
using ratiometric measurements. Each pair consists of the low value followed by the high value.
ai_charge_rngs
List[float] – Indicates in coulombs pairs of input charge ranges for the device. Each pair consists of the
low value followed by the high value.
ai_couplings
List[nidaqmx.constants.Coupling] – Indicates the coupling types supported by this device.
ai_current_int_excit_discrete_vals
List[float] – Indicates the set of discrete internal current excitation values supported by this device.
ai_current_rngs
List[float] – Indicates the pairs of current input ranges supported by this device. Each pair consists of the
low value, followed by the high value.
ai_dig_fltr_lowpass_cutoff_freq_discrete_vals
List[float] – Indicates the set of discrete lowpass cutoff frequencies supported by this device. If the device
supports ranges of lowpass cutoff frequencies, use AI.DigFltr.Lowpass.CutoffFreq.RangeVals to determine
supported frequencies.
ai_dig_fltr_lowpass_cutoff_freq_range_vals
List[float] – Indicates pairs of lowpass cutoff frequency ranges supported by this device. Each pair consists
of the low value, followed by the high value. If the device supports a set of discrete lowpass cutoff
frequencies, use AI.DigFltr.Lowpass.CutoffFreq.DiscreteVals to determine the supported frequencies.
ai_dig_fltr_types
List[nidaqmx.constants.FilterType] – Indicates the AI digital filter types supported by the device.

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ai_freq_rngs
List[float] – Indicates the pairs of frequency input ranges supported by this device. Each pair consists of
the low value, followed by the high value.
ai_gains
List[float] – Indicates the input gain settings supported by this device.
ai_lowpass_cutoff_freq_discrete_vals
List[float] – Indicates the set of discrete lowpass cutoff frequencies supported by this device. If the device supports ranges of lowpass cutoff frequencies, use ai_lowpass_cutoff_freq_range_vals to determine
supported frequencies.
ai_lowpass_cutoff_freq_range_vals
List[float] – Indicates pairs of lowpass cutoff frequency ranges supported by this device. Each pair consists
of the low value, followed by the high value. If the device supports a set of discrete lowpass cutoff
frequencies, use ai_lowpass_cutoff_freq_discrete_vals to determine the supported frequencies.
ai_max_multi_chan_rate
float – Indicates the maximum sampling rate for an analog input task from this device. To find the maximum rate for the task, take the minimum of ai_max_single_chan_rate or the indicated sampling rate of
this device divided by the number of channels to acquire data from (including cold-junction compensation
and autozero channels).
ai_max_single_chan_rate
float – Indicates the maximum rate for an analog input task if the task contains only a single channel from
this device.
ai_meas_types
List[nidaqmx.constants.UsageTypeAI] – Indicates the measurement types supported by the
physical channels of the device. Refer to ai_meas_types for information on specific channels.
ai_min_rate
float – Indicates the minimum rate for an analog input task on this device. NI-DAQmx returns a warning
or error if you attempt to sample at a slower rate.
ai_physical_chans
List[nidaqmx.system._collections.PhysicalChannelCollection] – Indicates a collection that contains all the
analog input physical channels available on the device.
ai_resistance_rngs
List[float] – Indicates pairs of input resistance ranges, in ohms, supported by devices that have the necessary signal conditioning to measure resistances. Each pair consists of the low value followed by the high
value.
ai_samp_modes
List[nidaqmx.constants.AcquisitionType] – Indicates sample modes supported by devices
that support sample clocked analog input.
ai_simultaneous_sampling_supported
bool – Indicates if the device supports simultaneous sampling.
ai_trig_usage
List[nidaqmx.constants.TriggerUsage] – Indicates the triggers supported by this device for an
analog input task.
ai_voltage_int_excit_discrete_vals
List[float] – Indicates the set of discrete internal voltage excitation values supported by this device. If the
device supports ranges of internal excitation values, use ai_voltage_int_excit_range_vals to determine
supported excitation values.

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ai_voltage_int_excit_range_vals
List[float] – Indicates pairs of internal voltage excitation ranges supported by this device. Each pair consists of the low value, followed by the high value. If the device supports a set of discrete internal excitation
values, use ai_voltage_int_excit_discrete_vals to determine the supported excitation values.
ai_voltage_rngs
List[float] – Indicates pairs of input voltage ranges supported by this device. Each pair consists of the low
value, followed by the high value.
anlg_trig_supported
bool – Indicates if the device supports analog triggering.
ao_current_rngs
List[float] – Indicates pairs of output current ranges supported by this device. Each pair consists of the low
value, followed by the high value.
ao_gains
List[float] – Indicates the output gain settings supported by this device.
ao_max_rate
float – Indicates the maximum analog output rate of the device.
ao_min_rate
float – Indicates the minimum analog output rate of the device.
ao_output_types
List[nidaqmx.constants.UsageTypeAO] – Indicates the generation types supported by the physical channels of the device. Refer to ao_output_types for information on specific channels.
ao_physical_chans
List[nidaqmx.system._collections.PhysicalChannelCollection] – Indicates a collection that contains all the
analog output physical channels available on the device.
ao_samp_clk_supported
bool – Indicates if the device supports the sample clock timing type for analog output tasks.
ao_samp_modes
List[nidaqmx.constants.AcquisitionType] – Indicates sample modes supported by devices
that support sample clocked analog output.
ao_trig_usage
List[nidaqmx.constants.TriggerUsage] – Indicates the triggers supported by this device for
analog output tasks.
ao_voltage_rngs
List[float] – Indicates pairs of output voltage ranges supported by this device. Each pair consists of the
low value, followed by the high value.
bus_type
nidaqmx.constants.BusType – Indicates the bus type of the device.
carrier_serial_num
int – Indicates the serial number of the device carrier. This value is zero if the carrier does not have a serial
number.
chassis_module_devices
List[nidaqmx.system.device.Device] – Indicates a list containing the names of the modules in
the chassis.
ci_max_size
int – Indicates in bits the size of the counters on the device.

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ci_max_timebase
float – Indicates in hertz the maximum counter timebase frequency.
ci_meas_types
List[nidaqmx.constants.UsageTypeCI] – Indicates the measurement types supported by the
physical channels of the device. Refer to ci_meas_types for information on specific channels.
ci_physical_chans
List[nidaqmx.system._collections.PhysicalChannelCollection] – Indicates a collection that contains all the
counter input physical channels available on the device.
ci_samp_clk_supported
bool – Indicates if the device supports the sample clock timing type for counter input tasks.
ci_samp_modes
List[nidaqmx.constants.AcquisitionType] – Indicates sample modes supported by devices
that support sample clocked counter input.
ci_trig_usage
List[nidaqmx.constants.TriggerUsage] – Indicates the triggers supported by this device for
counter input tasks.
co_max_size
int – Indicates in bits the size of the counters on the device.
co_max_timebase
float – Indicates in hertz the maximum counter timebase frequency.
co_output_types
List[nidaqmx.constants.UsageTypeCO] – Indicates the generation types supported by the physical channels of the device. Refer to co_output_types for information on specific channels.
co_physical_chans
List[nidaqmx.system._collections.PhysicalChannelCollection] – Indicates a collection that contains all the
counter output physical channels available on the device.
co_samp_clk_supported
bool – Indicates if the device supports Sample Clock timing for counter output tasks.
co_samp_modes
List[nidaqmx.constants.AcquisitionType] – Indicates sample modes supported by devices
that support sample clocked counter output.
co_trig_usage
List[nidaqmx.constants.TriggerUsage] – Indicates the triggers supported by this device for
counter output tasks.
compact_daq_chassis_device
nidaqmx.system.device.Device – Indicates the name of the CompactDAQ chassis that contains
this module.
compact_daq_slot_num
int – Indicates the slot number in which this module is located in the CompactDAQ chassis.
delete_network_device()
Deletes a Network DAQ device previously added to the host. If the device is reserved, it is unreserved
before it is removed.
dev_is_simulated
bool – Indicates if the device is a simulated device.

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dev_serial_num
int – Indicates the serial number of the device. This value is zero if the device does not have a serial
number.
di_lines
List[nidaqmx.system._collections.PhysicalChannelCollection] – Indicates a collection that contains all the
digital input lines available on the device.
di_max_rate
float – Indicates the maximum digital input rate of the device.
di_ports
List[nidaqmx.system._collections.PhysicalChannelCollection] – Indicates a collection that contains all the
digital input ports available on the device.
di_trig_usage
List[nidaqmx.constants.TriggerUsage] – Indicates the triggers supported by this device for
digital input tasks.
dig_trig_supported
bool – Indicates if the device supports digital triggering.
do_lines
List[nidaqmx.system._collections.PhysicalChannelCollection] – Indicates a collection that contains all the
digital output lines available on the device.
do_max_rate
float – Indicates the maximum digital output rate of the device.
do_ports
List[nidaqmx.system._collections.PhysicalChannelCollection] – Indicates a collection that contains all the
digital output ports available on the device.
do_trig_usage
List[nidaqmx.constants.TriggerUsage] – Indicates the triggers supported by this device for
digital output tasks.
name
str – Specifies the name of this device.
num_dma_chans
int – Indicates the number of DMA channels on the device.
pci_bus_num
int – Indicates the PCI bus number of the device.
pci_dev_num
int – Indicates the PCI slot number of the device.
product_category
nidaqmx.constants.ProductCategory – Indicates the product category of the device. This
category corresponds to the category displayed in MAX when creating NI-DAQmx simulated devices.
product_num
int – Indicates the unique hardware identification number for the device.
product_type
str – Indicates the product name of the device.
pxi_chassis_num
int – Indicates the PXI chassis number of the device, as identified in MAX.

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pxi_slot_num
int – Indicates the PXI slot number of the device.
reserve_network_device(override_reservation=None)
Reserves the Network DAQ device for the current host. Reservation is required to run NI-DAQmx tasks,
and the device must be added in MAX before it can be reserved.
Parameters override_reservation (Optional[bool]) – Indicates if an existing
reservation on the device should be overridden by this reservation. By default, this parameter
is set to false.
reset_device()
Immediately aborts all active tasks associated with a device, disconnects any routes, and returns the device
to an initialized state. Aborting a task immediately terminates the currently active operation, such as a read
or a write. Aborting a task puts the task into an unstable but recoverable state. To recover the task, use
DAQmx Start to restart the task or use DAQmx Stop to reset the task without starting it.
self_test_device()
Performs a brief test of device resources. If a failure occurs, refer to your device documentation for more
information.
tcpip_ethernet_ip
str – Indicates the IPv4 address of the Ethernet interface in dotted decimal format. This property returns
0.0.0.0 if the Ethernet interface cannot acquire an address.
tcpip_hostname
str – Indicates the IPv4 hostname of the device.
tcpip_wireless_ip
str – Indicates the IPv4 address of the 802.11 wireless interface in dotted decimal format. This property
returns 0.0.0.0 if the wireless interface cannot acquire an address.
tedshwteds_supported
bool – Indicates whether the device supports hardware TEDS.
terminals
List[str] – Indicates a list of all terminals on the device.
unreserve_network_device()
Unreserves or releases a Network DAQ device previously reserved by the host.

nidaqmx.system.physical_channel
class nidaqmx.system.physical_channel.PhysicalChannel(name)
Bases: object
Represents a DAQmx physical channel.
__init__(name)
Parameters name (str) – Specifies the name of the physical channel.
__weakref__
list of weak references to the object (if defined)
ai_input_srcs
List[str] – Indicates the list of input sources supported by the channel. Channels may support using the
signal from the I/O connector or one of several calibration signals.

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ai_meas_types
List[nidaqmx.constants.UsageTypeAI] – Indicates the measurement types supported by the
channel.
ai_term_cfgs
List[nidaqmx.constants.TerminalConfiguration] – Indicates the list of terminal configurations supported by the channel.
ao_manual_control_amplitude
float – Indicates the current value of the front panel amplitude control for the physical channel in volts.
ao_manual_control_enable
bool – Specifies if you can control the physical channel externally via a manual control located on the
device. You cannot simultaneously control a channel manually and with NI-DAQmx.
ao_manual_control_freq
float – Indicates the current value of the front panel frequency control for the physical channel in hertz.
ao_manual_control_short_detected
bool – Indicates whether the physical channel is currently disabled due to a short detected on the channel.
ao_output_types
List[nidaqmx.constants.UsageTypeAO] – Indicates the output types supported by the channel.
ao_power_amp_channel_enable
bool – Specifies whether to enable or disable a channel for amplification. This property can also be used
to check if a channel is enabled.
ao_power_amp_gain
float – Indicates the calibrated gain of the channel.
ao_power_amp_offset
float – Indicates the calibrated offset of the channel in volts.
ao_power_amp_overcurrent
bool – Indicates if the channel detected an overcurrent condition.
ao_power_amp_scaling_coeff
List[float] – Indicates the coefficients of a polynomial equation used to scale from pre-amplified values.
ao_power_up_output_types
List[nidaqmx.constants.AOPowerUpOutputBehavior] – Indicates the power up output types
supported by the channel.
ao_term_cfgs
List[nidaqmx.constants.TerminalConfiguration] – Indicates the list of terminal configurations supported by the channel.
ci_meas_types
List[nidaqmx.constants.UsageTypeCI] – Indicates the measurement types supported by the
channel.
clear_teds()
Removes TEDS information from the physical channel you specify. This function temporarily overrides
any TEDS configuration for the physical channel that you performed in MAX.
co_output_types
List[nidaqmx.constants.UsageTypeCO] – Indicates the output types supported by the channel.
configure_teds(file_path=u’‘)
Associates TEDS information with the physical channel you specify. If you do not specify the filename of
a data sheet in the file_path input, this function attempts to find a TEDS sensor connected to the physical

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channel. This function temporarily overrides any TEDS configuration for the physical channel that you
performed in MAX.
Parameters file_path (Optional[str]) – Is the path to a Virtual TEDS data sheet that
you want to associate with the physical channel. If you do not specify anything for this input,
this function attempts to find a TEDS sensor connected to the physical channel.
di_change_detect_supported
bool – Indicates if the change detection timing type is supported for the digital input physical channel.
di_port_width
int – Indicates in bits the width of digital input port.
di_samp_clk_supported
bool – Indicates if the sample clock timing type is supported for the digital input physical channel.
di_samp_modes
List[nidaqmx.constants.AcquisitionType] – Indicates the sample modes supported by devices
that support sample clocked digital input.
do_port_width
int – Indicates in bits the width of digital output port.
do_samp_clk_supported
bool – Indicates if the sample clock timing type is supported for the digital output physical channel.
do_samp_modes
List[nidaqmx.constants.AcquisitionType] – Indicates the sample modes supported by devices
that support sample clocked digital output.
name
str – Specifies the name of this physical channel.
teds_bit_stream
List[int] – Indicates the TEDS binary bitstream without checksums.
teds_mfg_id
int – Indicates the manufacturer ID of the sensor.
teds_model_num
int – Indicates the model number of the sensor.
teds_serial_num
int – Indicates the serial number of the sensor.
teds_template_ids
List[int] – Indicates the IDs of the templates in the bitstream in teds_bit_stream.
teds_version_letter
str – Indicates the version letter of the sensor.
teds_version_num
int – Indicates the version number of the sensor.
write_to_teds_from_array(bit_stream=None, basic_teds_options=)
Writes data from a 1D list of 8-bit unsigned integers to the TEDS sensor.
Parameters
• bit_stream (Optional[List[int]]) – Is the TEDS bitstream to write to the sensor. This bitstream must be constructed according to the IEEE 1451.4 specification.

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• basic_teds_options
(Optional[nidaqmx.constants.
WriteBasicTEDSOptions]) – Specifies how to handle basic TEDS data in the
bitstream.
write_to_teds_from_file(file_path=u’‘, basic_teds_options=)
Writes data from a virtual TEDS file to the TEDS sensor.
Parameters
• file_path (Optional[str]) – Specifies the filename of a virtual TEDS file that
contains the bitstream to write.
• basic_teds_options
(Optional[nidaqmx.constants.
WriteBasicTEDSOptions]) – Specifies how to handle basic TEDS data in the
bitstream.

nidaqmx.system.storage
nidaqmx.system.persisted_channel
class nidaqmx.system.storage.persisted_channel.PersistedChannel(name)
Bases: object
Represents a saved DAQmx global channel.
Use the DAQmx Persisted Channel properties to query information about programmatically saved global channels.
__init__(name)
Parameters name – Specifies the name of the global channel.
__weakref__
list of weak references to the object (if defined)
allow_interactive_deletion
bool – Indicates whether the global channel can be deleted through MAX.
allow_interactive_editing
bool – Indicates whether the global channel can be edited in the DAQ Assistant.
author
str – Indicates the author of the global channel.
delete()
Deletes this global channel from MAX.
This function does not remove the global channel from tasks that use it.
nidaqmx.system.persisted_scale
class nidaqmx.system.storage.persisted_scale.PersistedScale(name)
Bases: object
Represents a saved DAQmx custom scale.
Use the DAQmx Persisted Scale properties to query information about programmatically saved custom scales.
__init__(name)

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Parameters name – Specifies the name of the saved scale.
__weakref__
list of weak references to the object (if defined)
allow_interactive_deletion
bool – Indicates whether the custom scale can be deleted through MAX.
allow_interactive_editing
bool – Indicates whether the custom scale can be edited in the DAQ Assistant.
author
str – Indicates the author of the custom scale.
delete()
Deletes this custom scale from MAX.
This function does not remove the custom scale from virtual channels that use it.
load()
Loads this custom scale.
Returns Indicates the loaded Scale object.
Return type nidaqmx.scale.Scale
nidaqmx.system.persisted_task
class nidaqmx.system.storage.persisted_task.PersistedTask(name)
Bases: object
Represents a saved DAQmx task.
Use the DAQmx Persisted Task properties to query information about programmatically saved tasks.
__init__(name)
Parameters name – Specifies the name of the saved task.
__weakref__
list of weak references to the object (if defined)
allow_interactive_deletion
bool – Indicates whether the task can be deleted through MAX.
allow_interactive_editing
bool – Indicates whether the task can be edited in the DAQ Assistant.
author
str – Indicates the author of the task.
delete()
Deletes this task from MAX.
This function does not clear the copy of the task stored in memory. Use the DAQmx Clear Task function
to clear that copy of the task.
load()
Loads this saved task.
If you use this function to load a task, you must use DAQmx Clear Task to destroy it.
Returns Indicates the loaded Task object.
Return type nidaqmx.task.Task
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nidaqmx.system.watchdog
class nidaqmx.system.watchdog.WatchdogTask(device_name, task_name=u’‘, timeout=10)
Bases: object
Represents the watchdog configurations for a DAQmx task.
__init__(device_name, task_name=u’‘, timeout=10)
Creates and configures a task that controls the watchdog timer of a device. The timer activates when you
start the task.
Use the DAQmx Configure Watchdog Expiration States functions to configure channel expiration states.
This class does not program the watchdog timer on a real-time controller.
Parameters
• device_name (str) – Specifies is the name as configured in MAX of the device to
which this operation applies.
• task_name (str) – Specifies the name to assign to the task. If you use this constructor
in a loop and specify a name for the task, you must use the DAQmx Clear Task method
within the loop after you are finished with the task. Otherwise, NI-DAQmx attempts to
create multiple tasks with the same name, which results in an error.
• timeout (float) – Specifies the amount of time in seconds until the watchdog timer
expires. A value of -1 means the internal timer never expires. Set this input to -1 if you
use an Expiration Trigger to expire the watchdog task. If this time elapses, the device sets
the physical channels to the states you specify with the digital physical channel expiration
states input.
__weakref__
list of weak references to the object (if defined)
cfg_watchdog_ao_expir_states(expiration_states)
Configures the expiration states for an analog watchdog timer task.
Parameters expiration_states – (List[nidaqmx.system.watchdog.AOExpirationState]):
Contains the states to which to set analog physical channels when the watchdog timer expires. Each element of the list contains an analog physical channel name, the corresponding
expiration state, and the output type for that analog physical channel. The units of “expiration state” must be specified in volts for an analog output voltage expiration state, or amps
for an analog output current expiration state.
physical_channel (str): Specifies the analog output channel to modify. You cannot modify dedicated analog input lines.
expiration_state (float): Specifies the value to set the channel to upon expiration.
output_type (nidaqmx.constants.WatchdogAOExpirState): Specifies the output type of
the physical channel.
Returns Indicates the list of objects representing the configured expiration states.
Return type List[nidaqmx.system._watchdog_modules.expiration_state.ExpirationState]
cfg_watchdog_co_expir_states(expiration_states)
Configures the expiration states for a counter watchdog timer task.
Parameters expiration_states – (List[nidaqmx.system.watchdog.COExpirationState]):
Contains the states to which to set counter physical channels when the watchdog timer expires. Each element of the list contains a counter physical channel name and the corresponding state for that counter physical channel.

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physical_channel (str): Specifies the counter output channel to modify.
modify dedicated counter input lines.

You cannot

expiration_state (nidaqmx.constants.WatchdogCOExpirState): Specifies the value to
set the channel to upon expiration.
Returns Indicates the list of objects representing the configured expiration states.
Return type List[nidaqmx.system._watchdog_modules.expiration_state.ExpirationState]
cfg_watchdog_do_expir_states(expiration_states)
Configures the expiration states for a digital watchdog timer task.
Parameters expiration_states – (List[nidaqmx.system.watchdog.DOExpirationState]):
Contains the states to which to set digital physical channels when the watchdog timer expires.
Each element of the list contains a digital physical channel name and the corresponding state
for that digital physical channel.
physical_channel (str): Specifies the digital output channel to modify. You cannot modify dedicated digital input lines.
expiration_state (nidaqmx.constants.Level): Specifies the value to set the channel to
upon expiration.
Returns Indicates the list of objects representing the configured expiration states.
Return type List[nidaqmx.system._watchdog_modules.expiration_state.ExpirationState]
clear_expiration()
Unlock a device whose watchdog timer expired.
This function does not program the watchdog timer on a real-time controller. Use the Real-Time Watchdog
VIs to program the watchdog timer on a real-time controller.
close()
Clears the task.
Before clearing, this method aborts the task, if necessary, and releases any resources the task reserved. You
cannot use a task after you clear it unless you recreate the task.
If you create a DAQmx Task object within a loop, use this method within the loop after you are finished
with the task to avoid allocating unnecessary memory.
control(action)
Alters the state of a task according to the action you specify.
Parameters action (nidaqmx.constants.TaskMode) – Specifies how to alter the task
state.
expir_trig_dig_edge_edge
nidaqmx.constants.Edge – Specifies on which edge of a digital signal to expire the watchdog task.
expir_trig_dig_edge_src
str – Specifies the name of a terminal where a digital signal exists to use as the source of the Expiration
Trigger.
expir_trig_trig_on_network_conn_loss
bool – Specifies the watchdog timer behavior when the network connection is lost between the host and the
chassis. If set to true, the watchdog timer expires when the chassis detects the loss of network connection.
expir_trig_trig_type
nidaqmx.constants.TriggerType – Specifies the type of trigger to use to expire a watchdog task.
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nidaqmx.system._watchdog_modules.expiration_states_collection. ExpirationStatesCollection:
Gets the collection of expiration states for this watchdog task.
expired
bool – Indicates if the watchdog timer expired. You can read this property only while the task is running.
name
str – Indicates the name of the task.
reset_timer()
Reset the internal timer. You must continually reset the internal timer to prevent it from timing out and
locking the device.
This function does not program the watchdog timer on a real-time controller. Use the Real-Time Watchdog
VIs to program the watchdog timer on a real-time controller.
start()
Transitions the task to the running state to begin the measurement or generation. Using this method is
required for some applications and is optional for others.
stop()
Stops the task and returns it to the state the task was in before the DAQmx Start Task method ran.
timeout
float – Specifies in seconds the amount of time until the watchdog timer expires. A value of -1 means the
internal timer never expires. Set this input to -1 if you use an Expiration Trigger to expire the watchdog
task.
nidaqmx.system.expiration_state
class nidaqmx.system._watchdog_modules.expiration_state.ExpirationState(task_handle,
physical_channel)
Bases: object
Represents a DAQmx Watchdog expiration state.
expir_states_ao_state
float – Specifies the state to set the analog output physical channels when the watchdog task expires.
expir_states_ao_type
nidaqmx.constants.WatchdogAOExpirState – Specifies the output type of the analog output
physical channels when the watchdog task expires.
expir_states_co_state
nidaqmx.constants.WatchdogCOExpirState – Specifies the state to set the counter output
channel terminal when the watchdog task expires.
expir_states_do_state
nidaqmx.constants.Level – Specifies the state to which to set the digital physical channels when
the watchdog task expires. You cannot modify the expiration state of dedicated digital input physical
channels.
nidaqmx.system.expiration_states_collection

class nidaqmx.system._watchdog_modules.expiration_states_collection.ExpirationStatesCollectio
Bases: object
Contains the collection of expiration states for a DAQmx Watchdog Task.
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This class defines methods that implements a container object.

nidaqmx.task
class nidaqmx.task.Task(new_task_name=u’‘)
Bases: object
Represents a DAQmx Task.
__init__(new_task_name=u’‘)
Creates a DAQmx task.
Parameters new_task_name (Optional[str]) – Specifies the name to assign to the task.
If you use this method in a loop and specify a name for the task, you must use the DAQmx
Clear Task method within the loop after you are finished with the task. Otherwise, NIDAQmx attempts to create multiple tasks with the same name, which results in an error.
__weakref__
list of weak references to the object (if defined)
add_global_channels(global_channels)
Adds global virtual channels from MAX to the given task.
Parameters global_channels
(List[nidaqmx.system.storage.
persisted_channel.PersistedChannel]) – Specifies the channels to add
to the task.
These channels must be valid channels available from MAX. If you pass an invalid channel,
NI-DAQmx returns an error. This value is ignored if it is empty.
ai_channels
nidaqmx._task_modules.ai_channel_collection.AIChannelCollection – Gets the
collection of analog input channels for this task.
ao_channels
nidaqmx._task_modules.ao_channel_collection.AOChannelCollection – Gets the
collection of analog output channels for this task.
channel_names
List[str] – Indicates the names of all virtual channels in the task.
channels
nidaqmx._task_modules.channels.channel.Channel – Specifies a channel object that represents the entire list of virtual channels in this task.
ci_channels
nidaqmx._task_modules.ci_channel_collection.CIChannelCollection – Gets the
collection of counter input channels for this task.
close()
Clears the task.
Before clearing, this method aborts the task, if necessary, and releases any resources the task reserved. You
cannot use a task after you clear it unless you recreate the task.
If you create a DAQmx Task object within a loop, use this method within the loop after you are finished
with the task to avoid allocating unnecessary memory.

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co_channels
nidaqmx._task_modules.co_channel_collection.COChannelCollection – Gets the
collection of counter output channels for this task.
control(action)
Alters the state of a task according to the action you specify.
Parameters action (nidaqmx.constants.TaskMode) – Specifies how to alter the task
state.
devices
List[nidaqmx.system.device.Device] – Indicates a list of Device objects representing all the
devices in the task.
di_channels
nidaqmx._task_modules.di_channel_collection.DIChannelCollection – Gets the
collection of digital input channels for this task.
do_channels
nidaqmx._task_modules.do_channel_collection.DOChannelCollection – Gets the
collection of digital output channels for this task.
export_signals
nidaqmx._task_modules.export_signals.ExportSignals – Gets the exported signal
configurations for the task.
in_stream
nidaqmx._task_modules.in_stream.InStream – Gets the read configurations for the task.
is_task_done()
Queries the status of the task and indicates if it completed execution. Use this function to ensure that the
specified operation is complete before you stop the task.
Returns Indicates if the measurement or generation completed.
Return type bool
name
str – Indicates the name of the task.
number_of_channels
int – Indicates the number of virtual channels in the task.
number_of_devices
int – Indicates the number of devices in the task.
out_stream
nidaqmx._task_modules.out_stream.OutStream – Gets the write configurations for the
task.
read(number_of_samples_per_channel=,

time-

This read method is dynamic, and is capable of inferring an appropriate return type based on these factors:
- The channel type of the task. - The number of channels to read. - The number of samples per channel.
The data type of the samples returned is independently determined by the channel type of the task.
For digital input measurements, the data type of the samples returned is determined by the line grouping
format of the digital lines. If the line grouping format is set to “one channel for all lines”, the data type of
the samples returned is int. If the line grouping format is set to “one channel per line”, the data type of the
samples returned is boolean.

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If you do not set the number of samples per channel, this method assumes one sample was requested. This
method then returns either a scalar (1 channel to read) or a list (N channels to read).
If you set the number of samples per channel to ANY value (even 1), this method assumes multiple samples
were requested. This method then returns either a list (1 channel to read) or a list of lists (N channels to
read).
Parameters
• number_of_samples_per_channel (Optional[int]) – Specifies the number
of samples to read. If this input is not set, assumes samples to read is 1. Conversely, if this
input is set, assumes there are multiple samples to read.
If you set this input to nidaqmx.constants. READ_ALL_AVAILABLE, NI-DAQmx determines how many samples to read based on if the task acquires samples continuously or
acquires a finite number of samples.
If the task acquires samples continuously and you set this input to
nidaqmx.constants.READ_ALL_AVAILABLE, this method reads all the samples
currently available in the buffer.
If the task acquires a finite number of samples and you set this input to
nidaqmx.constants.READ_ALL_AVAILABLE, the method waits for the task to acquire
all requested samples, then reads those samples. If you set the “read_all_avail_samp”
property to True, the method reads the samples currently available in the buffer and does
not wait for the task to acquire all requested samples.
• timeout (Optional[float]) – Specifies the amount of time in seconds to wait for
samples to become available. If the time elapses, the method returns an error and any
samples read before the timeout elapsed. The default timeout is 10 seconds. If you set
timeout to nidaqmx.constants.WAIT_INFINITELY, the method waits indefinitely. If you
set timeout to 0, the method tries once to read the requested samples and returns an error
if it is unable to.
Returns
The samples requested in the form of a scalar, a list, or a list of lists. See method docstring
for more info.
NI-DAQmx scales the data to the units of the measurement, including any custom scaling
you apply to the channels. Use a DAQmx Create Channel method to specify these units.
Return type dynamic
Example
>>> task = Task()
>>> task.ai_channels.add_voltage_channel('Dev1/ai0:3')
>>> data = task.read()
>>> type(data)

>>> type(data[0])

register_done_event(callback_method)
Registers a callback function to receive an event when a task stops due to an error or when a finite acquisition task or finite generation task completes execution. A Done event does not occur when a task is
stopped explicitly, such as by calling DAQmx Stop Task.

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Parameters callback_method (function) – Specifies the function that you want
DAQmx to call when the event occurs. The function you pass in this parameter must have
the following prototype:
>>> def callback(task_handle, status, callback_data):
>>>
return 0

Upon entry to the callback, the task_handle parameter contains the handle to the task on
which the event occurred. The status parameter contains the status of the task when the event
occurred. If the status value is negative, it indicates an error. If the status value is zero, it
indicates no error. If the status value is positive, it indicates a warning. The callbackData
parameter contains the value you passed in the callbackData parameter of this function.
Passing None for this parameter unregisters the event callback function.
register_every_n_samples_acquired_into_buffer_event(sample_interval,
callback_method)
Registers a callback function to receive an event when the specified number of samples is written from the
device to the buffer. This function only works with devices that support buffered tasks.
When you stop a task explicitly any pending events are discarded. For example, if you call DAQmx Stop
Task then you do not receive any pending events.
Parameters
• sample_interval (int) – Specifies the number of samples after which each event
should occur.
• callback_method (function) – Specifies the function that you want DAQmx to call
when the event occurs. The function you pass in this parameter must have the following
prototype:
>>> def callback(task_handle, every_n_samples_event_type,
>>>
number_of_samples, callback_data):
>>>
return 0

Upon entry to the callback, the task_handle parameter contains the handle to the task on
which the event occurred. The every_n_samples_event_type parameter contains the EveryNSamplesEventType.ACQUIRED_INTO_BUFFER value. The number_of_samples
parameter contains the value you passed in the sample_interval parameter of this function.
The callback_data parameter contains the value you passed in the callback_data parameter
of this function.
Passing None for this parameter unregisters the event callback function.
register_every_n_samples_transferred_from_buffer_event(sample_interval, callback_method)
Registers a callback function to receive an event when the specified number of samples is written from the
buffer to the device. This function only works with devices that support buffered tasks.
When you stop a task explicitly any pending events are discarded. For example, if you call DAQmx Stop
Task then you do not receive any pending events.
Parameters
• sample_interval (int) – Specifies the number of samples after which each event
should occur.
• callback_method (function) – Specifies the function that you want DAQmx to call
when the event occurs. The function you pass in this parameter must have the following
prototype:

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>>> def callback(task_handle, every_n_samples_event_type,
>>>
number_of_samples, callback_data):
>>>
return 0

Upon entry to the callback, the task_handle parameter contains the handle to the task
on which the event occurred. The every_n_samples_event_type parameter contains
the EveryNSamplesEventType.TRANSFERRED_FROM_BUFFER value. The number_of_samples parameter contains the value you passed in the sample_interval parameter of this function. The callback_data parameter contains the value you passed in the
callback_data parameter of this function.
Passing None for this parameter unregisters the event callback function.
register_signal_event(signal_type, callback_method)
Registers a callback function to receive an event when the specified hardware event occurs.
When you stop a task explicitly any pending events are discarded. For example, if you call DAQmx Stop
Task then you do not receive any pending events.
Parameters
• signal_type (nidaqmx.constants.Signal) – Specifies the type of signal for
which you want to receive results.
• callback_method (function) – Specifies the function that you want DAQmx to call
when the event occurs. The function you pass in this parameter must have the following
prototype:
>>> def callback(task_handle, signal_type, callback_data):
>>>
return 0

Upon entry to the callback, the task_handle parameter contains the handle to the task on
which the event occurred. The signal_type parameter contains the integer value you passed
in the signal_type parameter of this function. The callback_data parameter contains the
value you passed in the callback_data parameter of this function.
Passing None for this parameter unregisters the event callback function.
save(save_as=u’‘, author=u’‘, overwrite_existing_task=False, allow_interactive_editing=True, allow_interactive_deletion=True)
Saves this task and any local channels it contains to MAX.
This function does not save global channels. Use the DAQmx Save Global Channel function to save global
channels.
Parameters
• save_as (Optional[str]) – Is the name to save the task, global channel, or custom
scale as. If you do not specify a value for this input, NI-DAQmx uses the name currently
assigned to the task, global channel, or custom scale.
• author (Optional[str]) – Is a name to store with the task, global channel, or custom
scale.
• overwrite_existing_task (Optional[bool]) – Specifies whether to overwrite a task of the same name if one is already saved in MAX. If this input is False and a
task of the same name is already saved in MAX, this function returns an error.
• allow_interactive_editing (Optional[bool]) – Specifies whether to allow the task, global channel, or custom scale to be edited in the DAQ Assistant. If al-

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low_interactive_editing is True, the DAQ Assistant must support all task or global channel
settings.
• allow_interactive_deletion (Optional[bool]) – Specifies whether to allow the task, global channel, or custom scale to be deleted through MAX.
start()
Transitions the task to the running state to begin the measurement or generation. Using this method is
required for some applications and is optional for others.
If you do not use this method, a measurement task starts automatically when the DAQmx Read method
runs. The autostart input of the DAQmx Write method determines if a generation task starts automatically
when the DAQmx Write method runs.
If you do not use the DAQmx Start Task method and the DAQmx Stop Task method when you use the
DAQmx Read method or the DAQmx Write method multiple times, such as in a loop, the task starts and
stops repeatedly. Starting and stopping a task repeatedly reduces the performance of the application.
stop()
Stops the task and returns it to the state the task was in before the DAQmx Start Task method ran or the
DAQmx Write method ran with the autostart input set to TRUE.
If you do not use the DAQmx Start Task method and the DAQmx Stop Task method when you use the
DAQmx Read method or the DAQmx Write method multiple times, such as in a loop, the task starts and
stops repeatedly. Starting and stopping a task repeatedly reduces the performance of the application.
timing
nidaqmx._task_modules.timing.Timing – Gets the timing configurations for the task.
triggers
nidaqmx._task_modules.triggers.Triggers – Gets the trigger configurations for the task.
wait_until_done(timeout=10.0)
Waits for the measurement or generation to complete.
Use this method to ensure that the specified operation is complete before you stop the task.
Parameters timeout (Optional[float]) – Specifies the maximum amount of time
in seconds to wait for the measurement or generation to complete. This method returns an error if the time elapses. The default is 10. If you set timeout (sec) to
nidaqmx.WAIT_INFINITELY, the method waits indefinitely. If you set timeout (sec) to 0,
the method checks once and returns an error if the measurement or generation is not done.
write(data, auto_start=, timeout=10.0)
Writes samples to the task or virtual channels you specify.
This write method is dynamic, and is capable of accepting the samples to write in the various forms for
most operations:
•Scalar: Single sample for 1 channel.
•List/1D numpy.ndarray: Multiple samples for 1 channel or 1 sample for multiple channels.
•List of lists/2D numpy.ndarray: Multiple samples for multiple channels.
The data type of the samples passed in must be appropriate for the channel type of the task.
For counter output pulse operations, this write method only accepts samples in these forms:
•Scalar CtrFreq, CtrTime, CtrTick (from nidaqmx.types): Single sample for 1 channel.
•List of CtrFreq, CtrTime, CtrTick (from nidaqmx.types): Multiple samples for 1 channel or 1 sample
for multiple channels.

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nidaqmx.task.channel
class nidaqmx._task_modules.channels.channel.Channel(task_handle,
tual_or_physical_name)
Bases: object

vir-

Represents virtual channel or a list of virtual channels.
chan_type
nidaqmx.constants.ChannelType – Indicates the type of the virtual channel.
channel_names
List[str] – Specifies the unflattened list of the virtual channels.
description
str – Specifies a user-defined description for the channel.
is_global
bool – Indicates whether the channel is a global channel.
name
str – Specifies the name of the virtual channel this object represents.
physical_channel
nidaqmx.system.physical_channel.PhysicalChannel – Specifies the name of the physical channel upon which this virtual channel is based.
save(save_as=u’‘, author=u’‘, overwrite_existing_channel=False, allow_interactive_editing=True, allow_interactive_deletion=True)
Saves this local or global channel to MAX as a global channel.
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Parameters
• save_as (Optional[str]) – Is the name to save the task, global channel, or custom
scale as. If you do not specify a value for this input, NI-DAQmx uses the name currently
assigned to the task, global channel, or custom scale.
• author (Optional[str]) – Is a name to store with the task, global channel, or custom
scale.
• overwrite_existing_channel (Optional[bool]) – Specifies whether to
overwrite a global channel of the same name if one is already saved in MAX. If this input
is False and a global channel of the same name is already saved in MAX, this function
returns an error.
• allow_interactive_editing (Optional[bool]) – Specifies whether to allow the task, global channel, or custom scale to be edited in the DAQ Assistant. If allow_interactive_editing is True, the DAQ Assistant must support all task or global channel
settings.
• allow_interactive_deletion (Optional[bool]) – Specifies whether to allow the task, global channel, or custom scale to be deleted through MAX.
nidaqmx.task.ai_channel
class nidaqmx._task_modules.channels.ai_channel.AIChannel(task_handle,
virtual_or_physical_name)
Bases: nidaqmx._task_modules.channels.channel.Channel
Represents one or more analog input virtual channels and their properties.
ai_ac_excit_freq
float – Specifies the AC excitation frequency in Hertz.
ai_ac_excit_sync_enable
bool – Specifies whether to synchronize the AC excitation source of the channel to that of another channel.
Synchronize the excitation sources of multiple channels to use multichannel sensors. Set this property to
False for the master channel and to True for the slave channels.
ai_ac_excit_wire_mode
nidaqmx.constants.ACExcitWireMode – Specifies the number of leads on the LVDT or RVDT.
Some sensors require you to tie leads together to create a four- or five- wire sensor. Refer to the sensor
documentation for more information.
ai_accel_4_wire_dc_voltage_sensitivity
float – Specifies the sensitivity of the 4 wire DC voltage acceleration sensor connected to the channel.
This value is the units you specify with AI.Accel.4WireDCVoltage.SensitivityUnits. Refer to the sensor
documentation to determine this value.
ai_accel_4_wire_dc_voltage_sensitivity_units
nidaqmx.constants.AccelSensitivityUnits
AI.Accel.4WireDCVoltage.Sensitivity.

–

Specifies

the

units

ai_accel_charge_sensitivity
float – Specifies the sensitivity of the charge acceleration sensor connected to the channel. This value is the
units you specify with AI.Accel.Charge.SensitivityUnits. Refer to the sensor documentation to determine
this value.
ai_accel_charge_sensitivity_units
nidaqmx.constants.AccelChargeSensitivityUnits
AI.Accel.Charge.Sensitivity.

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Specifies

the

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ai_accel_sensitivity
float – Specifies the sensitivity of the accelerometer. This value is in the units you specify with
ai_accel_sensitivity_units. Refer to the sensor documentation to determine this value.
ai_accel_sensitivity_units
nidaqmx.constants.AccelSensitivityUnits – Specifies the units of ai_accel_sensitivity.
ai_accel_units
nidaqmx.constants.AccelUnits – Specifies the units to use to return acceleration measurements
from the channel.
ai_acceld_b_ref
float – Specifies the decibel reference level in the units of the channel. When you read samples as a
waveform, the decibel reference level is included in the waveform attributes.
ai_adc_custom_timing_mode
int – Specifies the timing mode of the ADC when ai_adc_timing_mode is ADCTimingMode.CUSTOM.
ai_adc_timing_mode
nidaqmx.constants.ADCTimingMode – Specifies the ADC timing mode, controlling the tradeoff
between speed and effective resolution. Some ADC timing modes provide increased powerline noise
rejection. On devices that have an AI Convert clock, this setting affects both the maximum and default
values for ai_conv_rate. You must use the same ADC timing mode for all channels on a device, but you
can use different ADC timing modes for different devices in the same task.
ai_atten
float – Specifies the amount of attenuation to use.
ai_auto_zero_mode
nidaqmx.constants.AutoZeroType – Specifies how often to measure ground. NI-DAQmx subtracts the measured ground voltage from every sample.
ai_averaging_win_size
int – Specifies the number of samples to average while acquiring data. Increasing the number of samples
to average reduces noise in your measurement.
ai_bridge_balance_coarse_pot
int – Specifies by how much to compensate for offset in the signal. This value can be between 0 and 127.
ai_bridge_balance_fine_pot
int – Specifies by how much to compensate for offset in the signal. This value can be between 0 and 4095.
ai_bridge_cfg
nidaqmx.constants.BridgeConfiguration – Specifies the type of Wheatstone bridge connected to the channel.
ai_bridge_electrical_units
nidaqmx.constants.BridgeElectricalUnits – Specifies from which electrical unit to scale
data. Select the same unit that the sensor data sheet or calibration certificate uses for electrical values.
ai_bridge_initial_ratio
float – Specifies in volts per volt the ratio of output voltage from the bridge to excitation voltage supplied to the bridge while not under load. NI-DAQmx subtracts this value from any measurements before
applying scaling equations. If you set ai_bridge_initial_voltage, NI-DAQmx coerces this property to
ai_bridge_initial_voltage divided by ai_excit_actual_val. If you set this property, NI-DAQmx coerces
ai_bridge_initial_voltage to the value of this property times ai_excit_actual_val. If you set both this
property and ai_bridge_initial_voltage, and their values conflict, NI-DAQmx returns an error. To avoid
this error, reset one property to its default value before setting the other.
ai_bridge_initial_voltage
float – Specifies in volts the output voltage of the bridge while not under load. NI-DAQmx subtracts

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this value from any measurements before applying scaling equations. If you set ai_bridge_initial_ratio,
NI-DAQmx coerces this property to ai_bridge_initial_ratio times ai_excit_actual_val. This property is
set by DAQmx Perform Bridge Offset Nulling Calibration. If you set this property, NI-DAQmx coerces
ai_bridge_initial_ratio to the value of this property divided by ai_excit_actual_val. If you set both this
property and ai_bridge_initial_ratio, and their values conflict, NI- DAQmx returns an error. To avoid this
error, reset one property to its default value before setting the other.
ai_bridge_nom_resistance
float – Specifies in ohms the resistance of the bridge while not under load.
ai_bridge_physical_units
nidaqmx.constants.BridgePhysicalUnits – Specifies to which physical unit to scale electrical data. Select the same unit that the sensor data sheet or calibration certificate uses for physical values.
ai_bridge_poly_forward_coeff
List[float] – Specifies an list of coefficients for the polynomial that converts electrical values to physical
values. Each element of the list corresponds to a term of the equation. For example, if index three of the
list is 9, the fourth term of the equation is 9x^3.
ai_bridge_poly_reverse_coeff
List[float] – Specifies an list of coefficients for the polynomial that converts physical values to electrical
values. Each element of the list corresponds to a term of the equation. For example, if index three of the
list is 9, the fourth term of the equation is 9x^3.
ai_bridge_scale_type
nidaqmx.constants.ScaleType – Specifies the scaling type to use when scaling electrical values
from the sensor to physical units.
ai_bridge_shunt_cal_enable
bool – Specifies whether to enable a shunt calibration switch. Use ai_bridge_shunt_cal_select to select
the switch(es) to enable.
ai_bridge_shunt_cal_gain_adjust
float – Specifies the result of a shunt calibration. This property is set by DAQmx Perform Shunt Calibration. NI-DAQmx multiplies data read from the channel by the value of this property. This value should be
close to 1.0.
ai_bridge_shunt_cal_select
nidaqmx.constants.ShuntCalSelect – Specifies which shunt calibration switch(es) to enable.
Use ai_bridge_shunt_cal_enable to enable the switch(es) you specify with this property.
ai_bridge_shunt_cal_shunt_cal_a_actual_resistance
float – Specifies in ohms the actual value of the internal shunt calibration A resistor.
ai_bridge_shunt_cal_shunt_cal_a_resistance
float – Specifies in ohms the desired value of the internal shunt calibration A resistor.
ai_bridge_shunt_cal_shunt_cal_a_src
nidaqmx.constants.BridgeShuntCalSource – Specifies whether to use internal or external
shunt when Shunt Cal A is selected.
ai_bridge_shunt_cal_shunt_cal_b_actual_resistance
float – Specifies in ohms the actual value of the internal shunt calibration B resistor.
ai_bridge_shunt_cal_shunt_cal_b_resistance
float – Specifies in ohms the desired value of the internal shunt calibration B resistor.
ai_bridge_table_electrical_vals
List[float] – Specifies the list of electrical values that map to the values in ai_bridge_table_physical_vals.
Specify this value in the unit indicated by ai_bridge_electrical_units.

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ai_bridge_table_physical_vals
List[float] – Specifies the list of physical values that map to the values in ai_bridge_table_electrical_vals.
Specify this value in the unit indicated by ai_bridge_physical_units.
ai_bridge_two_point_lin_first_electrical_val
float – Specifies the first electrical value, corresponding to ai_bridge_two_point_lin_first_physical_val.
Specify this value in the unit indicated by ai_bridge_electrical_units.
ai_bridge_two_point_lin_first_physical_val
float – Specifies the first physical value, corresponding to ai_bridge_two_point_lin_first_electrical_val.
Specify this value in the unit indicated by ai_bridge_physical_units.
ai_bridge_two_point_lin_second_electrical_val
float
–
Specifies
the
second
electrical
value,
corresponding
to
ai_bridge_two_point_lin_second_physical_val.
Specify this value in the unit indicated by
ai_bridge_electrical_units.
ai_bridge_two_point_lin_second_physical_val
float
–
Specifies
the
second
physical
value,
corresponding
to
ai_bridge_two_point_lin_second_electrical_val.
Specify this value in the unit indicated by
ai_bridge_physical_units.
ai_bridge_units
nidaqmx.constants.BridgeUnits – Specifies in which unit to return voltage ratios from the channel.
ai_charge_units
nidaqmx.constants.ChargeUnits – Specifies the units to use to return charge measurements
from the channel.
ai_coupling
nidaqmx.constants.Coupling – Specifies the coupling for the channel.
ai_current_acrms_units
nidaqmx.constants.CurrentUnits – Specifies the units to use to return current RMS measurements from the channel.
ai_current_shunt_loc
nidaqmx.constants.CurrentShuntResistorLocation – Specifies the shunt resistor location for current measurements.
ai_current_shunt_resistance
float – Specifies in ohms the external shunt resistance for current measurements.
ai_current_units
nidaqmx.constants.CurrentUnits – Specifies the units to use to return current measurements
from the channel.
ai_custom_scale
nidaqmx.system.scale.Scale – Specifies the name of a custom scale for the channel.
ai_data_xfer_custom_threshold
int – Specifies the number of samples that must be in the FIFO to transfer data from the device if ai_data_xfer_req_cond is InputDataTransferCondition.ONBOARD_MEMORY_CUSTOM_THRESHOLD.
ai_data_xfer_mech
nidaqmx.constants.DataTransferActiveTransferMode – Specifies the data transfer mode
for the device.

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ai_data_xfer_req_cond
nidaqmx.constants.InputDataTransferCondition – Specifies under what condition to
transfer data from the onboard memory of the device to the buffer.
ai_dc_offset
float – Specifies the DC value to add to the input range of the device. Use ai_rng_high and ai_rng_low to
specify the input range. This offset is in the native units of the device .
ai_dev_scaling_coeff
List[float] – Indicates the coefficients of a polynomial equation that NI-DAQmx uses to scale values from
the native format of the device to volts. Each element of the list corresponds to a term of the equation. For
example, if index two of the list is 4, the third term of the equation is 4x^2. Scaling coefficients do not
account for any custom scales or sensors contained by the channel.
ai_dig_fltr_bandpass_center_freq
float – Specifies the center frequency of the passband for the digital filter.
ai_dig_fltr_bandpass_width
float – Specifies the width of the passband centered around the center frequency for the digital filter.
ai_dig_fltr_coeff
List[float] – Specifies the digital filter coefficients.
ai_dig_fltr_enable
bool – Specifies whether the digital filter is enabled or disabled.
ai_dig_fltr_highpass_cutoff_freq
float – Specifies the highpass cutoff frequency of the digital filter.
ai_dig_fltr_lowpass_cutoff_freq
float – Specifies the lowpass cutoff frequency of the digital filter.
ai_dig_fltr_notch_center_freq
float – Specifies the center frequency of the stopband for the digital filter.
ai_dig_fltr_notch_width
float – Specifies the width of the stopband centered around the center frequency for the digital filter.
ai_dig_fltr_order
int – Specifies the order of the digital filter.
ai_dig_fltr_response
nidaqmx.constants.FilterResponse – Specifies the digital filter response.
ai_dig_fltr_type
nidaqmx.constants.FilterType – Specifies the digital filter type.
ai_dither_enable
bool – Specifies whether to enable dithering. Dithering adds Gaussian noise to the input signal. You can
use dithering to achieve higher resolution measurements by over sampling the input signal and averaging
the results.
ai_eddy_current_prox_sensitivity
float – Specifies the sensitivity of the eddy current proximity probe . This value is in the units you specify
with ai_eddy_current_prox_sensitivity_units. Refer to the sensor documentation to determine this value.
ai_eddy_current_prox_sensitivity_units
nidaqmx.constants.EddyCurrentProxProbeSensitivityUnits – Specifies the units of
ai_eddy_current_prox_sensitivity.

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ai_eddy_current_prox_units
nidaqmx.constants.LengthUnits – Specifies the units to use to return proximity measurements
from the channel.
ai_enhanced_alias_rejection_enable
bool – Specifies whether to enable enhanced alias rejection. Leave this property set to the default value for
most applications.
ai_excit_actual_val
float – Specifies the actual amount of excitation supplied by an internal excitation source. If you read an
internal excitation source more precisely with an external device, set this property to the value you read.
NI-DAQmx ignores this value for external excitation. When performing shunt calibration, some devices
set this property automatically.
ai_excit_d_cor_ac
nidaqmx.constants.ExcitationDCorAC – Specifies if the excitation supply is DC or AC.
ai_excit_idle_output_behavior
nidaqmx.constants.ExcitationIdleOutputBehavior – Specifies whether this channel will
disable excitation after the task is uncommitted. Setting this to Zero Volts or Amps disables excitation
after task uncommit. Setting this attribute to Maintain Existing Value leaves the excitation on after task
uncommit.
ai_excit_sense
nidaqmx.constants.Sense – Specifies whether to use local or remote sense to sense excitation.
ai_excit_src
nidaqmx.constants.ExcitationSource – Specifies the source of excitation.
ai_excit_use_for_scaling
bool – Specifies if NI-DAQmx divides the measurement by the excitation. You should typically set this
property to True for ratiometric transducers. If you set this property to True, set ai_max and ai_min to
reflect the scaling.
ai_excit_use_multiplexed
bool – Specifies if the SCXI-1122 multiplexes the excitation to the upper half of the channels as it advances
through the scan list.
ai_excit_val
float – Specifies the amount of excitation that the sensor requires. If ai_excit_voltage_or_current is
ExcitationVoltageOrCurrent.USE_VOLTAGE, this value is in volts. If ai_excit_voltage_or_current
is ExcitationVoltageOrCurrent.USE_CURRENT, this value is in amperes.
ai_excit_voltage_or_current
nidaqmx.constants.ExcitationVoltageOrCurrent – Specifies if the channel uses current
or voltage excitation.
ai_filter_delay
float – Indicates the amount of time between when the ADC samples data and when the sample is read
by the host device. This value is in the units you specify with ai_filter_delay_units. You can adjust this
amount of time using ai_filter_delay_adjustment.
ai_filter_delay_adjustment
float – Specifies the amount of filter delay that gets removed if ai_remove_filter_delay is enabled. This
delay adjustment is in addition to the value indicated by ai_filter_delay. This delay adjustment is in the
units you specify with ai_filter_delay_units.
ai_filter_delay_units
nidaqmx.constants.DigitalWidthUnits – Specifies the units of ai_filter_delay and
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ai_force_iepe_sensor_sensitivity
float – Specifies the sensitivity of the IEPE force sensor connected to the channel. Specify this value in the
unit indicated by ai_force_iepe_sensor_sensitivity_units.
ai_force_iepe_sensor_sensitivity_units
nidaqmx.constants.ForceIEPESensorSensitivityUnits – Specifies the units for
ai_force_iepe_sensor_sensitivity.
ai_force_read_from_chan
bool – Specifies whether to read from the channel if it is a cold-junction compensation channel. By default,
DAQmx Read does not return data from cold-junction compensation channels. Setting this property to True
forces read operations to return the cold-junction compensation channel data with the other channels in the
task.
ai_force_units
nidaqmx.constants.ForceUnits – Specifies in which unit to return force or load measurements
from the channel.
ai_freq_hyst
float – Specifies in volts a window below ai_freq_thresh_voltage. The input voltage must pass below ai_freq_thresh_voltage minus this value before NI- DAQmx recognizes a waveform repetition at
ai_freq_thresh_voltage. Hysteresis can improve the measurement accuracy when the signal contains
noise or jitter.
ai_freq_thresh_voltage
float – Specifies the voltage level at which to recognize waveform repetitions. You should select a voltage
level that occurs only once within the entire period of a waveform. You also can select a voltage that occurs
only once while the voltage rises or falls.
ai_freq_units
nidaqmx.constants.FrequencyUnits – Specifies the units to use to return frequency measurements from the channel.
ai_gain
float – Specifies a gain factor to apply to the channel.
ai_impedance
nidaqmx.constants.Impedance1 – Specifies the input impedance of the channel.
ai_input_src
str – Specifies the source of the channel. You can use the signal from the I/O connector or one of several
calibration signals. Certain devices have a single calibration signal bus. For these devices, you must
specify the same calibration signal for all channels you connect to a calibration signal.
ai_lead_wire_resistance
float – Specifies in ohms the resistance of the wires that lead to the sensor.
ai_lossy_lsb_removal_compressed_samp_size
int – Specifies the number of bits to return in a raw sample when ai_raw_data_compression_type is set
to RawDataCompressionType.LOSSY_LSB_REMOVAL.
ai_lowpass_cutoff_freq
float – Specifies the frequency in Hertz that corresponds to the -3dB cutoff of the filter.
ai_lowpass_enable
bool – Specifies whether to enable the lowpass filter of the channel.
ai_lowpass_switch_cap_clk_src
nidaqmx.constants.SourceSelection – Specifies the source of the filter clock. If you need a
higher resolution for the filter, you can supply an external clock to increase the resolution. Refer to the
SCXI-1141/1142/1143 User Manual for more information.

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ai_lowpass_switch_cap_ext_clk_div
int – Specifies the divisor for the external clock when you set ai_lowpass_switch_cap_clk_src to SourceSelection.EXTERNAL. On the SCXI-1141, SCXI-1142, and SCXI-1143, NI-DAQmx determines the
filter cutoff by using the equation f/(100*n), where f is the external frequency, and n is the external clock
divisor. Refer to the SCXI-1141/1142/1143 User Manual for more information.
ai_lowpass_switch_cap_ext_clk_freq
float – Specifies the frequency of the external clock when you set ai_lowpass_switch_cap_clk_src to
SourceSelection.EXTERNAL. NI-DAQmx uses this frequency to set the pre- and post- filters on the
SCXI-1141, SCXI-1142, and SCXI-1143. On those devices, NI-DAQmx determines the filter cutoff by
using the equation f/(100*n), where f is the external frequency, and n is the external clock divisor. Refer
to the SCXI-1141/1142/1143 User Manual for more information.
ai_lowpass_switch_cap_out_clk_div
int – Specifies the divisor for the output clock. NI-DAQmx uses the cutoff frequency to determine the
output clock frequency. Refer to the SCXI-1141/1142/1143 User Manual for more information.
ai_lvdt_sensitivity
float – Specifies the sensitivity of the LVDT. This value is in the units you specify with
ai_lvdt_sensitivity_units. Refer to the sensor documentation to determine this value.
ai_lvdt_sensitivity_units
nidaqmx.constants.LVDTSensitivityUnits – Specifies the units of ai_lvdt_sensitivity.
ai_lvdt_units
nidaqmx.constants.LengthUnits – Specifies the units to use to return linear position measurements from the channel.
ai_max
float – Specifies the maximum value you expect to measure. This value is in the units you specify with a
units property. When you query this property, it returns the coerced maximum value that the device can
measure with the current settings.
ai_meas_type
nidaqmx.constants.UsageTypeAI – Indicates the measurement to take with the analog input
channel and in some cases, such as for temperature measurements, the sensor to use.
ai_mem_map_enable
bool – Specifies for NI-DAQmx to map hardware registers to the memory space of the application, if possible. Normally, NI- DAQmx maps hardware registers to memory accessible only to the kernel. Mapping
the registers to the memory space of the application increases performance. However, if the application
accesses the memory space mapped to the registers, it can adversely affect the operation of the device and
possibly result in a system crash.
ai_microphone_sensitivity
float – Specifies the sensitivity of the microphone. This value is in mV/Pa. Refer to the sensor documentation to determine this value.
ai_min
float – Specifies the minimum value you expect to measure. This value is in the units you specify with a
units property. When you query this property, it returns the coerced minimum value that the device can
measure with the current settings.
ai_open_chan_detect_enable
bool – Specifies whether to enable open channel detection.
ai_open_thrmcpl_detect_enable
bool – Specifies whether to apply the open thermocouple detection bias voltage to the channel. Changing
the value of this property on a channel may require settling time before the data returned is valid. To
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the task. Refer to your device specifications for the required settling time. When open thermocouple
detection is enabled, use open_thrmcpl_chans_exist to determine if any channels were open.
ai_pressure_units
nidaqmx.constants.PressureUnits – Specifies in which unit to return pressure measurements
from the channel.
ai_probe_atten
float – Specifies the amount of attenuation provided by the probe connected to the channel. Specify this
attenuation as a ratio.
ai_raw_data_compression_type
nidaqmx.constants.RawDataCompressionType – Specifies the type of compression to apply
to raw samples returned from the device.
ai_raw_samp_justification
nidaqmx.constants.DataJustification – Indicates the justification of a raw sample from the
device.
ai_raw_samp_size
int – Indicates in bits the size of a raw sample from the device.
ai_remove_filter_delay
bool – Specifies if filter delay removal is enabled on the device.
ai_resistance_cfg
nidaqmx.constants.ResistanceConfiguration – Specifies the resistance configuration for
the channel. NI-DAQmx uses this value for any resistance-based measurements, including temperature
measurement using a thermistor or RTD.
ai_resistance_units
nidaqmx.constants.ResistanceUnits – Specifies the units to use to return resistance measurements.
ai_resolution
float – Indicates the resolution of the analog-to-digital converter of the channel. This value is in the units
you specify with ai_resolution_units.
ai_resolution_units
nidaqmx.constants.ResolutionType – Indicates the units of ai_resolution.
ai_rng_high
float – Specifies the upper limit of the input range of the device. This value is in the native units of the
device. On E Series devices, for example, the native units is volts.
ai_rng_low
float – Specifies the lower limit of the input range of the device. This value is in the native units of the
device. On E Series devices, for example, the native units is volts.
ai_rosette_strain_gage_gage_orientation
float – Specifies gage orientation in degrees with respect to the X axis.
ai_rosette_strain_gage_rosette_meas_type
nidaqmx.constants.StrainGageRosetteMeasurementType – Specifies the type of rosette
measurement.
ai_rosette_strain_gage_rosette_type
nidaqmx.constants.StrainGageRosetteType – Indicates the type of rosette gage.
ai_rosette_strain_gage_strain_chans
List[str] – Indicates the raw strain channels that comprise the strain rosette.

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ai_rtd_a
float – Specifies the ‘A’ constant of the Callendar-Van Dusen equation. NI-DAQmx requires this value
when you use a custom RTD.
ai_rtd_b
float – Specifies the ‘B’ constant of the Callendar-Van Dusen equation. NI-DAQmx requires this value
when you use a custom RTD.
ai_rtd_c
float – Specifies the ‘C’ constant of the Callendar-Van Dusen equation. NI-DAQmx requires this value
when you use a custom RTD.
ai_rtd_r_0
float – Specifies in ohms the sensor resistance at 0 deg C. The Callendar-Van Dusen equation requires this
value. Refer to the sensor documentation to determine this value.
ai_rtd_type
nidaqmx.constants.RTDType – Specifies the type of RTD connected to the channel.
ai_rvdt_sensitivity
float – Specifies the sensitivity of the RVDT. This value is in the units you specify with
ai_rvdt_sensitivity_units. Refer to the sensor documentation to determine this value.
ai_rvdt_sensitivity_units
nidaqmx.constants.RVDTSensitivityUnits – Specifies the units of ai_rvdt_sensitivity.
ai_rvdt_units
nidaqmx.constants.AngleUnits – Specifies the units to use to return angular position measurements from the channel.
ai_samp_and_hold_enable
bool – Specifies whether to enable the sample and hold circuitry of the device. When you disable sample
and hold circuitry, a small voltage offset might be introduced into the signal. You can eliminate this offset
by using ai_auto_zero_mode to perform an auto zero on the channel.
ai_sound_pressure_max_sound_pressure_lvl
float – Specifies the maximum instantaneous sound pressure level you expect to measure. This value is in
decibels, referenced to 20 micropascals. NI-DAQmx uses the maximum sound pressure level to calculate
values in pascals for ai_max and ai_min for the channel.
ai_sound_pressure_units
nidaqmx.constants.SoundPressureUnits – Specifies the units to use to return sound pressure
measurements from the channel.
ai_sound_pressured_b_ref
float – Specifies the decibel reference level in the units of the channel. When you read samples as a
waveform, the decibel reference level is included in the waveform attributes. NI- DAQmx also uses the
decibel reference level when converting ai_sound_pressure_max_sound_pressure_lvl to a voltage level.
ai_strain_force_read_from_chan
bool – Specifies whether the data is returned by DAQmx Read when set on a raw strain channel that is part
of a rosette configuration.
ai_strain_gage_cfg
nidaqmx.constants.StrainGageBridgeType – Specifies the bridge configuration of the strain
gages.
ai_strain_gage_gage_factor
float – Specifies the sensitivity of the strain gage. Gage factor relates the change in electrical resistance to
the change in strain. Refer to the sensor documentation for this value.

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ai_strain_gage_poisson_ratio
float – Specifies the ratio of lateral strain to axial strain in the material you are measuring.
ai_strain_units
nidaqmx.constants.StrainUnits – Specifies the units to use to return strain measurements from
the channel.
ai_teds_is_teds
bool – Indicates if the virtual channel was initialized using a TEDS bitstream from the corresponding
physical channel.
ai_teds_units
str – Indicates the units defined by TEDS information associated with the channel.
ai_temp_units
nidaqmx.constants.TemperatureUnits – Specifies the units to use to return temperature measurements from the channel.
ai_term_cfg
nidaqmx.constants.TerminalConfiguration – Specifies the terminal configuration for the
channel.
ai_thrmcpl_cjc_chan
nidaqmx._task_modules.channels.channel.Channel – Indicates the channel that acquires
the temperature of the cold junction if ai_thrmcpl_cjc_src is CJCSource1.SCANNABLE_CHANNEL.
If the channel is a temperature channel, NI-DAQmx acquires the temperature in the correct units. Other
channel types, such as a resistance channel with a custom sensor, must use a custom scale to scale values
to degrees Celsius.
ai_thrmcpl_cjc_src
nidaqmx.constants.CJCSource – Indicates the source of cold-junction compensation.
ai_thrmcpl_cjc_val
float – Specifies the temperature of the cold junction if ai_thrmcpl_cjc_src is CJCSource1.CONSTANT_USER_VALUE. Specify this value in the units of the measurement.
ai_thrmcpl_lead_offset_voltage
float – Specifies the lead offset nulling voltage to subtract from measurements on a device. This property
is ignored if open thermocouple detection is disabled.
ai_thrmcpl_scale_type
nidaqmx.constants.ScaleType – Specifies the method or equation form that the thermocouple
scale uses.
ai_thrmcpl_type
nidaqmx.constants.ThermocoupleType – Specifies the type of thermocouple connected to the
channel. Thermocouple types differ in composition and measurement range.
ai_thrmstr_a
float – Specifies the ‘A’ constant of the Steinhart-Hart thermistor equation.
ai_thrmstr_b
float – Specifies the ‘B’ constant of the Steinhart-Hart thermistor equation.
ai_thrmstr_c
float – Specifies the ‘C’ constant of the Steinhart-Hart thermistor equation.
ai_thrmstr_r_1
float – Specifies in ohms the value of the reference resistor for the thermistor if you use voltage excitation.
NI-DAQmx ignores this value for current excitation.

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ai_torque_units
nidaqmx.constants.TorqueUnits – Specifies in which unit to return torque measurements from
the channel.
ai_usb_xfer_req_count
int – Specifies the maximum number of simultaneous USB transfers used to stream data. Modify this value
to affect performance under different combinations of operating system and device.
ai_usb_xfer_req_size
int – Specifies the maximum size of a USB transfer request in bytes. Modify this value to affect performance under different combinations of operating system and device.
ai_velocity_iepe_sensor_sensitivity
float – Specifies the sensitivity of the IEPE velocity sensor connected to the channel. Specify this value in
the unit indicated by ai_velocity_iepe_sensor_sensitivity_units.
ai_velocity_iepe_sensor_sensitivity_units
nidaqmx.constants.VelocityIEPESensorSensitivityUnits – Specifies the units for
ai_velocity_iepe_sensor_sensitivity.
ai_velocity_iepe_sensord_b_ref
float – Specifies the decibel reference level in the units of the channel. When you read samples as a
waveform, the decibel reference level is included in the waveform attributes.
ai_velocity_units
nidaqmx.constants.VelocityUnits – Specifies in which unit to return velocity measurements
from the channel.
ai_voltage_acrms_units
nidaqmx.constants.VoltageUnits – Specifies the units to use to return voltage RMS measurements from the channel.
ai_voltage_units
nidaqmx.constants.VoltageUnits – Specifies the units to use to return voltage measurements
from the channel.
ai_voltaged_b_ref
float – Specifies the decibel reference level in the units of the channel. When you read samples as a
waveform, the decibel reference level is included in the waveform attributes.
chan_type
nidaqmx.constants.ChannelType – Indicates the type of the virtual channel.
channel_names
List[str] – Specifies the unflattened list of the virtual channels.
description
str – Specifies a user-defined description for the channel.
is_global
bool – Indicates whether the channel is a global channel.
name
str – Specifies the name of the virtual channel this object represents.
physical_channel
nidaqmx.system.physical_channel.PhysicalChannel – Specifies the name of the physical channel upon which this virtual channel is based.
save(save_as=u’‘, author=u’‘, overwrite_existing_channel=False, allow_interactive_editing=True, allow_interactive_deletion=True)
Saves this local or global channel to MAX as a global channel.

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Parameters
• save_as (Optional[str]) – Is the name to save the task, global channel, or custom
scale as. If you do not specify a value for this input, NI-DAQmx uses the name currently
assigned to the task, global channel, or custom scale.
• author (Optional[str]) – Is a name to store with the task, global channel, or custom
scale.
• overwrite_existing_channel (Optional[bool]) – Specifies whether to
overwrite a global channel of the same name if one is already saved in MAX. If this input
is False and a global channel of the same name is already saved in MAX, this function
returns an error.
• allow_interactive_editing (Optional[bool]) – Specifies whether to allow the task, global channel, or custom scale to be edited in the DAQ Assistant. If allow_interactive_editing is True, the DAQ Assistant must support all task or global channel
settings.
• allow_interactive_deletion (Optional[bool]) – Specifies whether to allow the task, global channel, or custom scale to be deleted through MAX.
nidaqmx.task.ao_channel
class nidaqmx._task_modules.channels.ao_channel.AOChannel(task_handle,
virtual_or_physical_name)
Bases: nidaqmx._task_modules.channels.channel.Channel
Represents one or more analog output virtual channels and their properties.
ao_current_units
nidaqmx.constants.CurrentUnits – Specifies in what units to generate current on the channel.
Write data to the channel in the units you select.
ao_custom_scale
nidaqmx.system.scale.Scale – Specifies the name of a custom scale for the channel.
ao_dac_offset_ext_src
str – Specifies the source of the DAC offset voltage if ao_dac_offset_src is SourceSelection.EXTERNAL. The valid sources for this signal vary by device.
ao_dac_offset_src
nidaqmx.constants.SourceSelection – Specifies the source of the DAC offset voltage. The
value of this voltage source determines the full-scale value of the DAC.
ao_dac_offset_val
float – Specifies in volts the value of the DAC offset voltage. To achieve best accuracy, the DAC offset
value should be hand calibrated.
ao_dac_ref_allow_conn_to_gnd
bool – Specifies whether to allow grounding the internal DAC reference at run time. You must
set this property to True and set ao_dac_ref_src to SourceSelection.INTERNAL before you can set
ao_dac_ref_conn_to_gnd to True.
ao_dac_ref_conn_to_gnd
bool – Specifies whether to ground the internal DAC reference. Grounding the internal DAC reference has the effect of grounding all analog output channels and stopping waveform generation across
all analog output channels regardless of whether the channels belong to the current task. You can
ground the internal DAC reference only when ao_dac_ref_src is SourceSelection.INTERNAL and
ao_dac_ref_allow_conn_to_gnd is True.

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ao_dac_ref_ext_src
str – Specifies the source of the DAC reference voltage if ao_dac_ref_src is SourceSelection.EXTERNAL. The valid sources for this signal vary by device.
ao_dac_ref_src
nidaqmx.constants.SourceSelection – Specifies the source of the DAC reference voltage.
The value of this voltage source determines the full-scale value of the DAC.
ao_dac_ref_val
float – Specifies in volts the value of the DAC reference voltage. This voltage determines the full-scale
range of the DAC. Smaller reference voltages result in smaller ranges, but increased resolution.
ao_dac_rng_high
float – Specifies the upper limit of the output range of the device. This value is in the native units of the
device. On E Series devices, for example, the native units is volts.
ao_dac_rng_low
float – Specifies the lower limit of the output range of the device. This value is in the native units of the
device. On E Series devices, for example, the native units is volts.
ao_data_xfer_mech
nidaqmx.constants.DataTransferActiveTransferMode – Specifies the data transfer mode
for the device.
ao_data_xfer_req_cond
nidaqmx.constants.OutputDataTransferCondition – Specifies under what condition to
transfer data from the buffer to the onboard memory of the device.
ao_dev_scaling_coeff
List[float] – Indicates the coefficients of a linear equation that NI-DAQmx uses to scale values from a
voltage to the native format of the device. Each element of the list corresponds to a term of the equation.
The first element of the list corresponds to the y-intercept, and the second element corresponds to the slope.
Scaling coefficients do not account for any custom scales that may be applied to the channel.
ao_enhanced_image_rejection_enable
bool – Specifies whether to enable the DAC interpolation filter. Disable the interpolation filter to improve
DAC signal-to- noise ratio at the expense of degraded image rejection.
ao_filter_delay
float – Specifies the amount of time between when the sample is written by the host device and when the
sample is output by the DAC. This value is in the units you specify with ao_filter_delay_units.
ao_filter_delay_adjustment
float – Specifies an additional amount of time to wait between when the sample is written by the host device
and when the sample is output by the DAC. This delay adjustment is in addition to the value indicated by
ao_filter_delay. This delay adjustment is in the units you specify with ao_filter_delay_units.
ao_filter_delay_units
nidaqmx.constants.DigitalWidthUnits – Specifies the units of ao_filter_delay and
ao_filter_delay_adjustment.
ao_func_gen_amplitude
float – Specifies the zero-to-peak amplitude of the waveform to generate in volts. Zero and negative values
are valid.
ao_func_gen_fm_deviation
float – Specifies the FM deviation in hertz per volt when ao_func_gen_modulation_type is ModulationType.FM.
ao_func_gen_freq
float – Specifies the frequency of the waveform to generate in hertz.

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ao_func_gen_modulation_type
nidaqmx.constants.ModulationType – Specifies if the device generates a modulated version of
the waveform using the original waveform as a carrier and input from an external terminal as the signal.
ao_func_gen_offset
float – Specifies the voltage offset of the waveform to generate.
ao_func_gen_square_duty_cycle
float – Specifies the square wave duty cycle of the waveform to generate.
ao_func_gen_type
nidaqmx.constants.FuncGenType – Specifies the kind of the waveform to generate.
ao_gain
float – Specifies in decibels the gain factor to apply to the channel.
ao_idle_output_behavior
nidaqmx.constants.AOIdleOutputBehavior – Specifies the state of the channel when no generation is in progress.
ao_load_impedance
float – Specifies in ohms the load impedance connected to the analog output channel.
ao_max
float – Specifies the maximum value you expect to generate. The value is in the units you specify with
a units property. If you try to write a value larger than the maximum value, NI- DAQmx generates an
error. NI-DAQmx might coerce this value to a smaller value if other task settings restrict the device from
generating the desired maximum.
ao_mem_map_enable
bool – Specifies for NI-DAQmx to map hardware registers to the memory space of the application, if possible. Normally, NI- DAQmx maps hardware registers to memory accessible only to the kernel. Mapping
the registers to the memory space of the application increases performance. However, if the application
accesses the memory space mapped to the registers, it can adversely affect the operation of the device and
possibly result in a system crash.
ao_min
float – Specifies the minimum value you expect to generate. The value is in the units you specify with
a units property. If you try to write a value smaller than the minimum value, NI- DAQmx generates an
error. NI-DAQmx might coerce this value to a larger value if other task settings restrict the device from
generating the desired minimum.
ao_output_impedance
float – Specifies in ohms the impedance of the analog output stage of the device.
ao_output_type
nidaqmx.constants.UsageTypeAO – Indicates whether the channel generates voltage, current, or
a waveform.
ao_reglitch_enable
bool – Specifies whether to enable reglitching. The output of a DAC normally glitches whenever the DAC
is updated with a new value. The amount of glitching differs from code to code and is generally largest at
major code transitions. Reglitching generates uniform glitch energy at each code transition and provides
for more uniform glitches. Uniform glitch energy makes it easier to filter out the noise introduced from
glitching during spectrum analysis.
ao_resolution
float – Indicates the resolution of the digital-to-analog converter of the channel. This value is in the units
you specify with ao_resolution_units.

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ao_resolution_units
nidaqmx.constants.ResolutionType – Specifies the units of ao_resolution.
ao_term_cfg
nidaqmx.constants.TerminalConfiguration – Specifies the terminal configuration of the
channel.
ao_usb_xfer_req_count
int – Specifies the maximum number of simultaneous USB transfers used to stream data. Modify this value
to affect performance under different combinations of operating system and device.
ao_usb_xfer_req_size
int – Specifies the maximum size of a USB transfer request in bytes. Modify this value to affect performance under different combinations of operating system and device.
ao_use_only_on_brd_mem
bool – Specifies whether to write samples directly to the onboard memory of the device, bypassing the
memory buffer. Generally, you cannot update onboard memory directly after you start the task. Onboard
memory includes data FIFOs.
ao_voltage_current_limit
float – Specifies the current limit, in amperes, for the voltage channel.
ao_voltage_units
nidaqmx.constants.VoltageUnits – Specifies in what units to generate voltage on the channel.
Write data to the channel in the units you select.
chan_type
nidaqmx.constants.ChannelType – Indicates the type of the virtual channel.
channel_names
List[str] – Specifies the unflattened list of the virtual channels.
description
str – Specifies a user-defined description for the channel.
is_global
bool – Indicates whether the channel is a global channel.
name
str – Specifies the name of the virtual channel this object represents.
physical_channel
nidaqmx.system.physical_channel.PhysicalChannel – Specifies the name of the physical channel upon which this virtual channel is based.
save(save_as=u’‘, author=u’‘, overwrite_existing_channel=False, allow_interactive_editing=True, allow_interactive_deletion=True)
Saves this local or global channel to MAX as a global channel.
Parameters
• save_as (Optional[str]) – Is the name to save the task, global channel, or custom
scale as. If you do not specify a value for this input, NI-DAQmx uses the name currently
assigned to the task, global channel, or custom scale.
• author (Optional[str]) – Is a name to store with the task, global channel, or custom
scale.
• overwrite_existing_channel (Optional[bool]) – Specifies whether to
overwrite a global channel of the same name if one is already saved in MAX. If this input
is False and a global channel of the same name is already saved in MAX, this function
returns an error.
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This value is in the units you specify with

ci_ang_encoder_pulses_per_rev
int – Specifies the number of pulses the encoder generates per revolution. This value is the number of
pulses on either signal A or signal B, not the total number of pulses on both signal A and signal B.
ci_ang_encoder_units
nidaqmx.constants.AngleUnits – Specifies the units to use to return angular position measurements from the channel.
ci_count
int – Indicates the current value of the count register.
ci_count_edges_active_edge
nidaqmx.constants.Edge – Specifies on which edges to increment or decrement the counter.
ci_count_edges_count_dir_dig_fltr_enable
bool – Specifies whether to apply the pulse width filter to the signal.
ci_count_edges_count_dir_dig_fltr_min_pulse_width
float – Specifies in seconds the minimum pulse width the filter recognizes.
ci_count_edges_count_dir_dig_fltr_timebase_rate
float – Specifies in hertz the rate of the pulse width filter timebase. NI-DAQmx uses this value to compute
settings for the filter.
ci_count_edges_count_dir_dig_fltr_timebase_src
str – Specifies the input terminal of the signal to use as the timebase of the pulse width filter.
ci_count_edges_count_dir_dig_sync_enable
bool – Specifies whether to synchronize recognition of transitions in the signal to the internal timebase of
the device.
ci_count_edges_count_dir_logic_lvl_behavior
nidaqmx.constants.LogicLvlBehavior – Specifies the logic level behavior on the count reset
line.

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ci_count_edges_count_dir_term_cfg
nidaqmx.constants.TerminalConfiguration – Specifies the input terminal configuration.
ci_count_edges_count_reset_active_edge
nidaqmx.constants.Edge – Specifies on which edge of the signal to reset the count.
ci_count_edges_count_reset_dig_fltr_enable
bool – Specifies whether to apply the pulse width filter to the signal.
ci_count_edges_count_reset_dig_fltr_min_pulse_width
float – Specifies the minimum pulse width the filter recognizes.
ci_count_edges_count_reset_dig_fltr_timebase_rate
float – Specifies in hertz the rate of the pulse width filter timebase. NI-DAQmx uses this value to compute
settings for the filter.
ci_count_edges_count_reset_dig_fltr_timebase_src
str – Specifies the input of the signal to use as the timebase of the pulse width filter.
ci_count_edges_count_reset_dig_sync_enable
bool – Specifies whether to synchronize recognition of transitions in the signal to the internal timebase of
the device.
ci_count_edges_count_reset_enable
bool – Specifies whether to reset
ci_count_edges_count_reset_term.

the

count

the

active

edge

specified

with

ci_count_edges_count_reset_logic_lvl_behavior
nidaqmx.constants.LogicLvlBehavior – Specifies the logic level behavior on the count reset
line.
ci_count_edges_count_reset_reset_cnt
int – Specifies the value to reset the count to.
ci_count_edges_count_reset_term
str – Specifies the input terminal of the signal to reset the count.
ci_count_edges_count_reset_term_cfg
nidaqmx.constants.TerminalConfiguration – Specifies the input terminal configuration.
ci_count_edges_dig_fltr_enable
bool – Specifies whether to apply the pulse width filter to the signal.
ci_count_edges_dig_fltr_min_pulse_width
float – Specifies in seconds the minimum pulse width the filter recognizes.
ci_count_edges_dig_fltr_timebase_rate
float – Specifies in hertz the rate of the pulse width filter timebase. NI-DAQmx uses this value to compute
settings for the filter.
ci_count_edges_dig_fltr_timebase_src
str – Specifies the input terminal of the signal to use as the timebase of the pulse width filter.
ci_count_edges_dig_sync_enable
bool – Specifies whether to synchronize recognition of transitions in the signal to the internal timebase of
the device.
ci_count_edges_dir
nidaqmx.constants.CountDirection – Specifies whether to increment or decrement the counter
on each edge.

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ci_count_edges_dir_term
str – Specifies the source terminal of the digital signal that controls the count direction if
ci_count_edges_dir is CountDirection1.EXTERNAL_SOURCE.
ci_count_edges_gate_dig_fltr_enable
bool – Specifies whether to apply the pulse width filter to the gate input signal.
ci_count_edges_gate_dig_fltr_min_pulse_width
float – Specifies in seconds the minimum pulse width the digital filter recognizes.
ci_count_edges_gate_dig_fltr_timebase_rate
float – Specifies in hertz the rate of the pulse width filter timebase. NI-DAQmx uses this value to compute
settings for the filter.
ci_count_edges_gate_dig_fltr_timebase_src
str – Specifies the input terminal of the signal to use as the timebase of the pulse width filter.
ci_count_edges_gate_enable
bool – Specifies whether to enable the functionality to gate the counter input signal for a count edges
measurement.
ci_count_edges_gate_logic_lvl_behavior
nidaqmx.constants.LogicLvlBehavior – Specifies the logic level behavior on the gate input
line.
ci_count_edges_gate_term
str – Specifies the gate terminal.
ci_count_edges_gate_term_cfg
nidaqmx.constants.TerminalConfiguration – Specifies the gate terminal configuration.
ci_count_edges_gate_when
nidaqmx.constants.Level – Specifies whether the counter gates input pulses while the signal is
high or low.
ci_count_edges_initial_cnt
int – Specifies the starting value from which to count.
ci_count_edges_logic_lvl_behavior
nidaqmx.constants.LogicLvlBehavior – Specifies the logic level behavior on the input line.
ci_count_edges_term
str – Specifies the input terminal of the signal to measure.
ci_count_edges_term_cfg
nidaqmx.constants.TerminalConfiguration – Specifies the input terminal configuration.
ci_ctr_timebase_active_edge
nidaqmx.constants.Edge – Specifies whether a timebase cycle is from rising edge to rising edge
or from falling edge to falling edge.
ci_ctr_timebase_dig_fltr_enable
bool – Specifies whether to apply the pulse width filter to the signal.
ci_ctr_timebase_dig_fltr_min_pulse_width
float – Specifies in seconds the minimum pulse width the filter recognizes.
ci_ctr_timebase_dig_fltr_timebase_rate
float – Specifies in hertz the rate of the pulse width filter timebase. NI-DAQmx uses this value to compute
settings for the filter.
ci_ctr_timebase_dig_fltr_timebase_src
str – Specifies the input terminal of the signal to use as the timebase of the pulse width filter.

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ci_ctr_timebase_dig_sync_enable
bool – Specifies whether to synchronize recognition of transitions in the signal to the internal timebase of
the device.
ci_ctr_timebase_master_timebase_div
int – Specifies the divisor for an external counter timebase. You can divide the counter timebase in order
to measure slower signals without causing the count register to roll over.
ci_ctr_timebase_rate
float – Specifies in Hertz the frequency of the counter timebase. Specifying the rate of a counter timebase
allows you to take measurements in terms of time or frequency rather than in ticks of the timebase. If you
use an external timebase and do not specify the rate, you can take measurements only in terms of ticks of
the timebase.
ci_ctr_timebase_src
str – Specifies the terminal of the timebase to use for the counter.
ci_custom_scale
nidaqmx.system.scale.Scale – Specifies the name of a custom scale for the channel.
ci_data_xfer_mech
nidaqmx.constants.DataTransferActiveTransferMode – Specifies the data transfer mode
for the channel.
ci_data_xfer_req_cond
nidaqmx.constants.InputDataTransferCondition – Specifies under what condition to
transfer data from the onboard memory of the device to the buffer.
ci_dup_count_prevention
bool – Specifies whether to enable duplicate count prevention for the channel. Duplicate count prevention
is enabled by default. Setting ci_prescaler disables duplicate count prevention unless you explicitly enable
it.
ci_duty_cycle_dig_fltr_enable
bool – Specifies whether to apply the pulse width filter to the signal.
ci_duty_cycle_dig_fltr_min_pulse_width
float – Specifies in seconds the minimum pulse width the digital filter recognizes.
ci_duty_cycle_dig_fltr_timebase_rate
float – Specifies in hertz the rate of the pulse width filter timebase. NI-DAQmx uses this value to compute
settings for the filter.
ci_duty_cycle_dig_fltr_timebase_src
str – Specifies the input terminal of the signal to use as the timebase of the pulse width filter.
ci_duty_cycle_logic_lvl_behavior
nidaqmx.constants.LogicLvlBehavior – Specifies the logic level behavior on the input line.
ci_duty_cycle_starting_edge
nidaqmx.constants.Edge – Specifies which edge of the input signal to begin the duty cycle measurement.
ci_duty_cycle_term
str – Specifies the input terminal of the signal to measure.
ci_duty_cycle_term_cfg
nidaqmx.constants.TerminalConfiguration – Specifies the input terminal configuration.
ci_encoder_a_input_dig_fltr_enable
bool – Specifies whether to apply the pulse width filter to the signal.

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ci_encoder_a_input_dig_fltr_min_pulse_width
float – Specifies in seconds the minimum pulse width the filter recognizes.
ci_encoder_a_input_dig_fltr_timebase_rate
float – Specifies in hertz the rate of the pulse width filter timebase. NI-DAQmx uses this value to compute
settings for the filter.
ci_encoder_a_input_dig_fltr_timebase_src
str – Specifies the input terminal of the signal to use as the timebase of the pulse width filter.
ci_encoder_a_input_dig_sync_enable
bool – Specifies whether to synchronize recognition of transitions in the signal to the internal timebase of
the device.
ci_encoder_a_input_logic_lvl_behavior
nidaqmx.constants.LogicLvlBehavior – Specifies the logic level behavior on the input line.
ci_encoder_a_input_term
str – Specifies the terminal to which signal A is connected.
ci_encoder_a_input_term_cfg
nidaqmx.constants.TerminalConfiguration – Specifies the input terminal configuration.
ci_encoder_b_input_dig_fltr_enable
bool – Specifies whether to apply the pulse width filter to the signal.
ci_encoder_b_input_dig_fltr_min_pulse_width
float – Specifies in seconds the minimum pulse width the filter recognizes.
ci_encoder_b_input_dig_fltr_timebase_rate
float – Specifies in hertz the rate of the pulse width filter timebase. NI-DAQmx uses this value to compute
settings for the filter.
ci_encoder_b_input_dig_fltr_timebase_src
str – Specifies the input terminal of the signal to use as the timebase of the pulse width filter.
ci_encoder_b_input_dig_sync_enable
bool – Specifies whether to synchronize recognition of transitions in the signal to the internal timebase of
the device.
ci_encoder_b_input_logic_lvl_behavior
nidaqmx.constants.LogicLvlBehavior – Specifies the logic level behavior on the input line.
ci_encoder_b_input_term
str – Specifies the terminal to which signal B is connected.
ci_encoder_b_input_term_cfg
nidaqmx.constants.TerminalConfiguration – Specifies the input terminal configuration.
ci_encoder_decoding_type
nidaqmx.constants.EncoderType – Specifies how to count and interpret the pulses the encoder
generates on signal A and signal B. EncoderType2.X_1, EncoderType2.X_2, and EncoderType2.X_4
are valid for quadrature encoders only. EncoderType2.TWO_PULSE_COUNTING is valid for twopulse encoders only.
ci_encoder_z_index_enable
bool – Specifies whether to use Z indexing for the channel.
ci_encoder_z_index_phase
nidaqmx.constants.EncoderZIndexPhase – Specifies the states at which signal A and signal
B must be while signal Z is high for NI-DAQmx to reset the measurement. If signal Z is never high

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while signal A and signal B are high, for example, you must choose a phase other than EncoderZIndexPhase1.AHIGH_BHIGH.
ci_encoder_z_index_val
float – Specifies the value to which to reset the measurement when signal Z is high and signal A and signal
B are at the states you specify with ci_encoder_z_index_phase. Specify this value in the units of the
measurement.
ci_encoder_z_input_dig_fltr_enable
bool – Specifies whether to apply the pulse width filter to the signal.
ci_encoder_z_input_dig_fltr_min_pulse_width
float – Specifies in seconds the minimum pulse width the filter recognizes.
ci_encoder_z_input_dig_fltr_timebase_rate
float – Specifies in hertz the rate of the pulse width filter timebase. NI-DAQmx uses this value to compute
settings for the filter.
ci_encoder_z_input_dig_fltr_timebase_src
str – Specifies the input terminal of the signal to use as the timebase of the pulse width filter.
ci_encoder_z_input_dig_sync_enable
bool – Specifies whether to synchronize recognition of transitions in the signal to the internal timebase of
the device.
ci_encoder_z_input_logic_lvl_behavior
nidaqmx.constants.LogicLvlBehavior – Specifies the logic level behavior on the input line.
ci_encoder_z_input_term
str – Specifies the terminal to which signal Z is connected.
ci_encoder_z_input_term_cfg
nidaqmx.constants.TerminalConfiguration – Specifies the input terminal configuration.
ci_freq_dig_fltr_enable
bool – Specifies whether to apply the pulse width filter to the signal.
ci_freq_dig_fltr_min_pulse_width
float – Specifies in seconds the minimum pulse width the filter recognizes.
ci_freq_dig_fltr_timebase_rate
float – Specifies in hertz the rate of the pulse width filter timebase. NI-DAQmx uses this value to compute
settings for the filter.
ci_freq_dig_fltr_timebase_src
str – Specifies the input terminal of the signal to use as the timebase of the pulse width filter.
ci_freq_dig_sync_enable
bool – Specifies whether to synchronize recognition of transitions in the signal to the internal timebase of
the device.
ci_freq_div
int – Specifies the value by which to divide the input signal if ci_freq_meas_meth is CounterFrequencyMethod.LARGE_RANGE_2_COUNTERS. The larger the divisor, the more accurate the measurement. However, too large a value could cause the count register to roll over, which results in an incorrect
measurement.
ci_freq_enable_averaging
bool – Specifies whether to enable averaging mode for Sample Clock-timed frequency measurements.
ci_freq_logic_lvl_behavior
nidaqmx.constants.LogicLvlBehavior – Specifies the logic level behavior on the input line.

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ci_freq_meas_meth
nidaqmx.constants.CounterFrequencyMethod – Specifies the method to use to measure the
frequency of the signal.
ci_freq_meas_time
float – Specifies in seconds the length of time to measure the frequency of the signal if
ci_freq_meas_meth is CounterFrequencyMethod.HIGH_FREQUENCY_2_COUNTERS. Measurement accuracy increases with increased measurement time and with increased signal frequency. If you
measure a high-frequency signal for too long, however, the count register could roll over, which results in
an incorrect measurement.
ci_freq_starting_edge
nidaqmx.constants.Edge – Specifies between which edges to measure the frequency of the signal.
ci_freq_term
str – Specifies the input terminal of the signal to measure.
ci_freq_term_cfg
nidaqmx.constants.TerminalConfiguration – Specifies the input terminal configuration.
ci_freq_units
nidaqmx.constants.FrequencyUnits – Specifies the units to use to return frequency measurements.
ci_gps_sync_method
nidaqmx.constants.GpsSignalType – Specifies the method to use to synchronize the counter to
a GPS receiver.
ci_gps_sync_src
str – Specifies the terminal to which the GPS synchronization signal is connected.
ci_lin_encoder_dist_per_pulse
float – Specifies the distance to measure for each pulse the encoder generates on signal A or signal B. This
value is in the units you specify with ci_lin_encoder_units.
ci_lin_encoder_initial_pos
float – Specifies the position of the encoder when the measurement begins. This value is in the units you
specify with ci_lin_encoder_units.
ci_lin_encoder_units
nidaqmx.constants.LengthUnits – Specifies the units to use to return linear encoder measurements from the channel.
ci_max
float – Specifies the maximum value you expect to measure. This value is in the units you specify with a
units property. When you query this property, it returns the coerced maximum value that the hardware can
measure with the current settings.
ci_max_meas_period
float – Specifies the maximum period (in seconds) in which the device will recognize signals. For frequency measurements, a signal with a higher period than the one set in this property will return 0 Hz. For
duty cycle, the device will return 0 or 1 depending on the state of the line during the max defined period
of time. Period measurements will return NaN. Pulse width measurement will return zero.
ci_meas_type
nidaqmx.constants.UsageTypeCI – Indicates the measurement to take with the channel.
ci_mem_map_enable
bool – Specifies for NI-DAQmx to map hardware registers to the memory space of the application, if possible. Normally, NI- DAQmx maps hardware registers to memory accessible only to the kernel. Mapping
the registers to the memory space of the application increases performance. However, if the application

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accesses the memory space mapped to the registers, it can adversely affect the operation of the device and
possibly result in a system crash.
ci_min
float – Specifies the minimum value you expect to measure. This value is in the units you specify with a
units property. When you query this property, it returns the coerced minimum value that the hardware can
measure with the current settings.
ci_num_possibly_invalid_samps
int – Indicates the number of samples that the device might have overwritten before it could transfer them
to the buffer.
ci_output_state
nidaqmx.constants.Level – Indicates the current state of the out terminal of the counter.
ci_period_dig_fltr_enable
bool – Specifies whether to apply the pulse width filter to the signal.
ci_period_dig_fltr_min_pulse_width
float – Specifies in seconds the minimum pulse width the filter recognizes.
ci_period_dig_fltr_timebase_rate
float – Specifies in hertz the rate of the pulse width filter timebase. NI-DAQmx uses this value to compute
settings for the filter.
ci_period_dig_fltr_timebase_src
str – Specifies the input terminal of the signal to use as the timebase of the pulse width filter.
ci_period_dig_sync_enable
bool – Specifies whether to synchronize recognition of transitions in the signal to the internal timebase of
the device.
ci_period_div
int – Specifies the value by which to divide the input signal if ci_period_meas_meth is CounterFrequencyMethod.LARGE_RANGE_2_COUNTERS. The larger the divisor, the more accurate the measurement. However, too large a value could cause the count register to roll over, which results in an
incorrect measurement.
ci_period_enable_averaging
bool – Specifies whether to enable averaging mode for Sample Clock-timed period measurements.
ci_period_logic_lvl_behavior
nidaqmx.constants.LogicLvlBehavior – Specifies the logic level behavior on the input line.
ci_period_meas_meth
nidaqmx.constants.CounterFrequencyMethod – Specifies the method to use to measure the
period of the signal.
ci_period_meas_time
float – Specifies in seconds the length of time to measure the period of the signal if ci_period_meas_meth
is CounterFrequencyMethod.HIGH_FREQUENCY_2_COUNTERS. Measurement accuracy increases with increased measurement time and with increased signal frequency. If you measure a highfrequency signal for too long, however, the count register could roll over, which results in an incorrect
measurement.
ci_period_starting_edge
nidaqmx.constants.Edge – Specifies between which edges to measure the period of the signal.
ci_period_term
str – Specifies the input terminal of the signal to measure.

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ci_period_term_cfg
nidaqmx.constants.TerminalConfiguration – Specifies the input terminal configuration.
ci_period_units
nidaqmx.constants.TimeUnits – Specifies the unit to use to return period measurements.
ci_prescaler
int – Specifies the divisor to apply to the signal you connect to the counter source terminal. Scaled
data that you read takes this setting into account. You should use a prescaler only when you connect
an external signal to the counter source terminal and when that signal has a higher frequency than the
fastest onboard timebase. Setting this value disables duplicate count prevention unless you explicitly set
ci_dup_count_prevention to True.
ci_pulse_freq_dig_fltr_enable
bool – Specifies whether to apply a digital filter to the signal to measure.
ci_pulse_freq_dig_fltr_min_pulse_width
float – Specifies in seconds the minimum pulse width the filter recognizes.
ci_pulse_freq_dig_fltr_timebase_rate
float – Specifies in hertz the rate of the digital filter timebase. NI-DAQmx uses this value to compute
settings for the filter.
ci_pulse_freq_dig_fltr_timebase_src
str – Specifies the terminal of the signal to use as the timebase of the digital filter.
ci_pulse_freq_dig_sync_enable
bool – Specifies whether to synchronize recognition of transitions in the signal to the internal timebase of
the device.
ci_pulse_freq_logic_lvl_behavior
nidaqmx.constants.LogicLvlBehavior – Specifies the logic level behavior on the count reset
line.
ci_pulse_freq_starting_edge
nidaqmx.constants.Edge – Specifies on which edge of the input signal to begin pulse measurement.
ci_pulse_freq_term
str – Specifies the input terminal of the signal to measure.
ci_pulse_freq_term_cfg
nidaqmx.constants.TerminalConfiguration – Specifies the input terminal configuration.
ci_pulse_freq_units
nidaqmx.constants.FrequencyUnits – Specifies the units to use to return pulse specifications
in terms of frequency.
ci_pulse_ticks_dig_fltr_enable
bool – Specifies whether to apply a digital filter to the signal to measure.
ci_pulse_ticks_dig_fltr_min_pulse_width
float – Specifies in seconds the minimum pulse width the filter recognizes.
ci_pulse_ticks_dig_fltr_timebase_rate
float – Specifies in hertz the rate of the digital filter timebase. NI-DAQmx uses this value to compute
settings for the filter.
ci_pulse_ticks_dig_fltr_timebase_src
str – Specifies the terminal of the signal to use as the timebase of the digital filter.

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ci_pulse_ticks_dig_sync_enable
bool – Specifies whether to synchronize recognition of transitions in the signal to the internal timebase of
the device.
ci_pulse_ticks_logic_lvl_behavior
nidaqmx.constants.LogicLvlBehavior – Specifies the logic level behavior on the count reset
line.
ci_pulse_ticks_starting_edge
nidaqmx.constants.Edge – Specifies on which edge of the input signal to begin pulse measurement.
ci_pulse_ticks_term
str – Specifies the input terminal of the signal to measure.
ci_pulse_ticks_term_cfg
nidaqmx.constants.TerminalConfiguration – Specifies the input terminal configuration.
ci_pulse_time_dig_fltr_enable
bool – Specifies whether to apply a digital filter to the signal to measure.
ci_pulse_time_dig_fltr_min_pulse_width
float – Specifies in seconds the minimum pulse width the filter recognizes.
ci_pulse_time_dig_fltr_timebase_rate
float – Specifies in hertz the rate of the digital filter timebase. NI-DAQmx uses this value to compute
settings for the filter.
ci_pulse_time_dig_fltr_timebase_src
str – Specifies the terminal of the signal to use as the timebase of the digital filter.
ci_pulse_time_dig_sync_enable
bool – Specifies whether to synchronize recognition of transitions in the signal to the internal timebase of
the device.
ci_pulse_time_logic_lvl_behavior
nidaqmx.constants.LogicLvlBehavior – Specifies the logic level behavior on the count reset
line.
ci_pulse_time_starting_edge
nidaqmx.constants.Edge – Specifies on which edge of the input signal to begin pulse measurement.
ci_pulse_time_term
str – Specifies the input terminal of the signal to measure.
ci_pulse_time_term_cfg
nidaqmx.constants.TerminalConfiguration – Specifies the input terminal configuration.
ci_pulse_time_units
nidaqmx.constants.TimeUnits – Specifies the units to use to return pulse specifications in terms
of high time and low time.
ci_pulse_width_dig_fltr_enable
bool – Specifies whether to apply the pulse width filter to the signal.
ci_pulse_width_dig_fltr_min_pulse_width
float – Specifies in seconds the minimum pulse width the filter recognizes.
ci_pulse_width_dig_fltr_timebase_rate
float – Specifies in hertz the rate of the pulse width filter timebase. NI-DAQmx uses this value to compute
settings for the filter.

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ci_pulse_width_dig_fltr_timebase_src
str – Specifies the input terminal of the signal to use as the timebase of the pulse width filter.
ci_pulse_width_dig_sync_enable
bool – Specifies whether to synchronize recognition of transitions in the signal to the internal timebase of
the device.
ci_pulse_width_logic_lvl_behavior
nidaqmx.constants.LogicLvlBehavior – Specifies the logic level behavior on the input line.
ci_pulse_width_starting_edge
nidaqmx.constants.Edge – Specifies on which edge of the input signal to begin each pulse width
measurement.
ci_pulse_width_term
str – Specifies the input terminal of the signal to measure.
ci_pulse_width_term_cfg
nidaqmx.constants.TerminalConfiguration – Specifies the input terminal configuration.
ci_pulse_width_units
nidaqmx.constants.TimeUnits – Specifies the units to use to return pulse width measurements.
ci_samp_clk_overrun_behavior
nidaqmx.constants.SampClkOverrunBehavior – Specifies the counter behavior when data is
read but a new value was not detected during a sample clock.
ci_samp_clk_overrun_sentinel_val
int – Specifies the sentinel value returned when the No New Sample Behavior is set to Sentinel Value.
ci_semi_period_dig_fltr_enable
bool – Specifies whether to apply the pulse width filter to the signal.
ci_semi_period_dig_fltr_min_pulse_width
float – Specifies in seconds the minimum pulse width the filter recognizes.
ci_semi_period_dig_fltr_timebase_rate
float – Specifies in hertz the rate of the pulse width filter timebase. NI-DAQmx uses this value to compute
settings for the filter.
ci_semi_period_dig_fltr_timebase_src
str – Specifies the input terminal of the signal to use as the timebase of the pulse width filter.
ci_semi_period_dig_sync_enable
bool – Specifies whether to synchronize recognition of transitions in the signal to the internal timebase of
the device.
ci_semi_period_logic_lvl_behavior
nidaqmx.constants.LogicLvlBehavior – Specifies the logic level behavior on the count reset
line.
ci_semi_period_starting_edge
nidaqmx.constants.Edge – Specifies on which edge of the input signal to begin semi-period measurement. Semi-period measurements alternate between high time and low time, starting on this edge.
ci_semi_period_term
str – Specifies the input terminal of the signal to measure.
ci_semi_period_term_cfg
nidaqmx.constants.TerminalConfiguration – Specifies the input terminal configuration.
ci_semi_period_units
nidaqmx.constants.TimeUnits – Specifies the units to use to return semi-period measurements.

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ci_tc_reached
bool – Indicates whether the counter rolled over. When you query this property, NI-DAQmx resets it to
False.
ci_thresh_voltage
float – Specifies the digital threshold value in Volts for high and low input transitions. Some devices do
not support this for differential channels.
ci_timestamp_initial_seconds
int – Specifies the number of seconds that elapsed since the beginning of the current year. This value is
ignored if ci_gps_sync_method is GpsSignalType1.IRIGB.
ci_timestamp_units
nidaqmx.constants.TimeUnits – Specifies the units to use to return timestamp measurements.
ci_two_edge_sep_first_dig_fltr_enable
bool – Specifies whether to apply the pulse width filter to the signal.
ci_two_edge_sep_first_dig_fltr_min_pulse_width
float – Specifies in seconds the minimum pulse width the filter recognizes.
ci_two_edge_sep_first_dig_fltr_timebase_rate
float – Specifies in hertz the rate of the pulse width filter timebase. NI-DAQmx uses this value to compute
settings for the filter.
ci_two_edge_sep_first_dig_fltr_timebase_src
str – Specifies the input terminal of the signal to use as the timebase of the pulse width filter.
ci_two_edge_sep_first_dig_sync_enable
bool – Specifies whether to synchronize recognition of transitions in the signal to the internal timebase of
the device.
ci_two_edge_sep_first_edge
nidaqmx.constants.Edge – Specifies on which edge of the first signal to start each measurement.
ci_two_edge_sep_first_logic_lvl_behavior
nidaqmx.constants.LogicLvlBehavior – Specifies the logic level behavior on the input line.
ci_two_edge_sep_first_term
str – Specifies the source terminal of the digital signal that starts each measurement.
ci_two_edge_sep_first_term_cfg
nidaqmx.constants.TerminalConfiguration – Specifies the input terminal configuration.
ci_two_edge_sep_second_dig_fltr_enable
bool – Specifies whether to apply the pulse width filter to the signal.
ci_two_edge_sep_second_dig_fltr_min_pulse_width
float – Specifies in seconds the minimum pulse width the filter recognizes.
ci_two_edge_sep_second_dig_fltr_timebase_rate
float – Specifies in hertz the rate of the pulse width filter timebase. NI-DAQmx uses this value to compute
settings for the filter.
ci_two_edge_sep_second_dig_fltr_timebase_src
str – Specifies the input terminal of the signal to use as the timebase of the pulse width filter.
ci_two_edge_sep_second_dig_sync_enable
bool – Specifies whether to synchronize recognition of transitions in the signal to the internal timebase of
the device.
ci_two_edge_sep_second_edge
nidaqmx.constants.Edge – Specifies on which edge of the second signal to stop each measurement.

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ci_two_edge_sep_second_logic_lvl_behavior
nidaqmx.constants.LogicLvlBehavior – Specifies the logic level behavior on the count reset
line.
ci_two_edge_sep_second_term
str – Specifies the source terminal of the digital signal that stops each measurement.
ci_two_edge_sep_second_term_cfg
nidaqmx.constants.TerminalConfiguration – Specifies the input terminal configuration.
ci_two_edge_sep_units
nidaqmx.constants.TimeUnits – Specifies the units to use to return two-edge separation measurements from the channel.
ci_usb_xfer_req_count
int – Specifies the maximum number of simultaneous USB transfers used to stream data. Modify this value
to affect performance under different combinations of operating system and device.
ci_usb_xfer_req_size
int – Specifies the maximum size of a USB transfer request in bytes. Modify this value to affect performance under different combinations of operating system and device.
ci_velocity_a_input_dig_fltr_enable
bool – Specifies whether to apply the pulse width filter to the signal.
ci_velocity_a_input_dig_fltr_min_pulse_width
float – Specifies in seconds the minimum pulse width the digital filter recognizes.
ci_velocity_a_input_dig_fltr_timebase_rate
float – Specifies in hertz the rate of the pulse width filter timebase. NI-DAQmx uses this value to compute
settings for the filter.
ci_velocity_a_input_dig_fltr_timebase_src
str – Specifies the input terminal of the signal to use as the timebase of the pulse width filter.
ci_velocity_a_input_logic_lvl_behavior
nidaqmx.constants.LogicLvlBehavior – Specifies the logic level behavior of the input terminal.
ci_velocity_a_input_term
str – Specifies the terminal to which signal A is connected.
ci_velocity_a_input_term_cfg
nidaqmx.constants.TerminalConfiguration – Specifies the input terminal configuration.
ci_velocity_ang_encoder_pulses_per_rev
int – Specifies the number of pulses the encoder generates per revolution. This value is the number of
pulses on either signal A or signal B, not the total number of pulses on both signal A and signal B.
ci_velocity_ang_encoder_units
nidaqmx.constants.AngularVelocityUnits – Specifies the units to use to return angular velocity counter measurements.
ci_velocity_b_input_dig_fltr_enable
bool – Specifies whether to apply the pulse width filter to the signal.
ci_velocity_b_input_dig_fltr_min_pulse_width
float – Specifies in seconds the minimum pulse width the digital filter recognizes.
ci_velocity_b_input_dig_fltr_timebase_rate
float – Specifies in hertz the rate of the pulse width filter timebase. NI-DAQmx uses this value to compute
settings for the filter.

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ci_velocity_b_input_dig_fltr_timebase_src
str – Specifies the input terminal of the signal to use as the timebase of the pulse width filter.
ci_velocity_b_input_logic_lvl_behavior
nidaqmx.constants.LogicLvlBehavior – Specifies the logic level behavior of the input terminal.
ci_velocity_b_input_term
str – Specifies the terminal to which signal B is connected.
ci_velocity_b_input_term_cfg
nidaqmx.constants.TerminalConfiguration – Specifies the input terminal configuration.
ci_velocity_div
int – Specifies the value by which to divide the input signal.
ci_velocity_encoder_decoding_type
nidaqmx.constants.EncoderType – Specifies how to count and interpret the pulses the encoder
generates on signal A and signal B. X1, X2, and X4 are valid for quadrature encoders only. Two Pulse
Counting is valid for two-pulse encoders only.
ci_velocity_lin_encoder_dist_per_pulse
float – Specifies the distance to measure for each pulse the encoder generates on signal A or signal B. This
value is in the units you specify in CI.Velocity.LinEncoder.DistUnits.
ci_velocity_lin_encoder_units
nidaqmx.constants.VelocityUnits – Specifies the units to use to return linear encoder velocity
measurements from the channel.
ci_velocity_meas_time
float – Specifies in seconds the length of time to measure the velocity of the signal.
description
str – Specifies a user-defined description for the channel.
is_global
bool – Indicates whether the channel is a global channel.
name
str – Specifies the name of the virtual channel this object represents.
physical_channel
nidaqmx.system.physical_channel.PhysicalChannel – Specifies the name of the physical channel upon which this virtual channel is based.
save(save_as=u’‘, author=u’‘, overwrite_existing_channel=False, allow_interactive_editing=True, allow_interactive_deletion=True)
Saves this local or global channel to MAX as a global channel.
Parameters
• save_as (Optional[str]) – Is the name to save the task, global channel, or custom
scale as. If you do not specify a value for this input, NI-DAQmx uses the name currently
assigned to the task, global channel, or custom scale.
• author (Optional[str]) – Is a name to store with the task, global channel, or custom
scale.
• overwrite_existing_channel (Optional[bool]) – Specifies whether to
overwrite a global channel of the same name if one is already saved in MAX. If this input
is False and a global channel of the same name is already saved in MAX, this function
returns an error.

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• allow_interactive_editing (Optional[bool]) – Specifies whether to allow the task, global channel, or custom scale to be edited in the DAQ Assistant. If allow_interactive_editing is True, the DAQ Assistant must support all task or global channel
settings.
• allow_interactive_deletion (Optional[bool]) – Specifies whether to allow the task, global channel, or custom scale to be deleted through MAX.
nidaqmx.task.co_channel
class nidaqmx._task_modules.channels.co_channel.COChannel(task_handle,
virtual_or_physical_name)
Bases: nidaqmx._task_modules.channels.channel.Channel
Represents one or more counter output virtual channels and their properties.
chan_type
nidaqmx.constants.ChannelType – Indicates the type of the virtual channel.
channel_names
List[str] – Specifies the unflattened list of the virtual channels.
co_auto_incr_cnt
int – Specifies a number of timebase ticks by which to increase the time spent in the idle state for each
successive pulse.
co_constrained_gen_mode
nidaqmx.constants.ConstrainedGenMode – Specifies constraints to apply when the counter
generates pulses. Constraining the counter reduces the device resources required for counter operation.
Constraining the counter can also allow additional analog or counter tasks on the device to run concurrently. For continuous counter tasks, NI-DAQmx consumes no device resources when the counter is constrained. For finite counter tasks, resource use increases with the frequency regardless of the constraint
mode. However, fixed frequency constraints significantly reduce resource usage, and fixed duty cycle
constraint marginally reduces it.
co_count
int – Indicates the current value of the count register.
co_ctr_timebase_active_edge
nidaqmx.constants.Edge – Specifies whether a timebase cycle is from rising edge to rising edge
or from falling edge to falling edge.
co_ctr_timebase_dig_fltr_enable
bool – Specifies whether to apply the pulse width filter to the signal.
co_ctr_timebase_dig_fltr_min_pulse_width
float – Specifies in seconds the minimum pulse width the filter recognizes.
co_ctr_timebase_dig_fltr_timebase_rate
float – Specifies in hertz the rate of the pulse width filter timebase. NI-DAQmx uses this value to compute
settings for the filter.
co_ctr_timebase_dig_fltr_timebase_src
str – Specifies the input terminal of the signal to use as the timebase of the pulse width filter.
co_ctr_timebase_dig_sync_enable
bool – Specifies whether to synchronize recognition of transitions in the signal to the internal timebase of
the device.

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co_ctr_timebase_master_timebase_div
int – Specifies the divisor for an external counter timebase. You can divide the counter timebase in order
to generate slower signals without causing the count register to roll over.
co_ctr_timebase_rate
float – Specifies in Hertz the frequency of the counter timebase. Specifying the rate of a counter timebase
allows you to define output pulses in seconds rather than in ticks of the timebase. If you use an external
timebase and do not specify the rate, you can define output pulses only in ticks of the timebase.
co_ctr_timebase_src
str – Specifies the terminal of the timebase to use for the counter. Typically, NI-DAQmx uses one of the
internal counter timebases when generating pulses. Use this property to specify an external timebase and
produce custom pulse widths that are not possible using the internal timebases.
co_data_xfer_mech
nidaqmx.constants.DataTransferActiveTransferMode – Specifies the data transfer mode
for the device. For buffered operations, use DMA or USB Bulk. For non-buffered operations, use Polled.
co_data_xfer_req_cond
nidaqmx.constants.OutputDataTransferCondition – Specifies under what condition to
transfer data from the buffer to the onboard memory of the device.
co_enable_initial_delay_on_retrigger
bool – Specifies whether to apply the initial delay to retriggered pulse trains.
co_mem_map_enable
bool – Specifies for NI-DAQmx to map hardware registers to the memory space of the application, if possible. Normally, NI- DAQmx maps hardware registers to memory accessible only to the kernel. Mapping
the registers to the memory space of the application increases performance. However, if the application
accesses the memory space mapped to the registers, it can adversely affect the operation of the device and
possibly result in a system crash.
co_output_state
nidaqmx.constants.Level – Indicates the current state of the output terminal of the counter.
co_output_type
nidaqmx.constants.UsageTypeCO – Indicates how to define pulses generated on the channel.
co_prescaler
int – Specifies the divisor to apply to the signal you connect to the counter source terminal. Pulse generations defined by frequency or time take this setting into account, but pulse generations defined by ticks do
not. You should use a prescaler only when you connect an external signal to the counter source terminal
and when that signal has a higher frequency than the fastest onboard timebase.
co_pulse_done
bool – Indicates if the task completed pulse generation. Use this value for retriggerable pulse generation
when you need to determine if the device generated the current pulse. For retriggerable tasks, when you
query this property, NI-DAQmx resets it to False.
co_pulse_duty_cyc
float – Specifies the duty cycle of the pulses. The duty cycle of a signal is the width of the pulse divided
by period. NI- DAQmx uses this ratio and the pulse frequency to determine the width of the pulses and the
delay between pulses.
co_pulse_freq
float – Specifies the frequency of the pulses to generate. This value is in the units you specify with
co_pulse_freq_units or when you create the channel.
co_pulse_freq_initial_delay
float – Specifies in seconds the amount of time to wait before generating the first pulse.

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co_pulse_freq_units
nidaqmx.constants.FrequencyUnits – Specifies the units in which to define pulse frequency.
co_pulse_high_ticks
int – Specifies the number of ticks the pulse is high.
co_pulse_high_time
float – Specifies the amount of time that the pulse is at a high voltage. This value is in the units you specify
with co_pulse_time_units or when you create the channel.
co_pulse_idle_state
nidaqmx.constants.Level – Specifies the resting state of the output terminal.
co_pulse_low_ticks
int – Specifies the number of ticks the pulse is low.
co_pulse_low_time
float – Specifies the amount of time that the pulse is at a low voltage. This value is in the units you specify
with co_pulse_time_units or when you create the channel.
co_pulse_term
str – Specifies on which terminal to generate pulses.
co_pulse_ticks_initial_delay
int – Specifies the number of ticks to wait before generating the first pulse.
co_pulse_time_initial_delay
float – Specifies in seconds the amount of time to wait before generating the first pulse.
co_pulse_time_units
nidaqmx.constants.TimeUnits – Specifies the units in which to define high and low pulse time.
co_rdy_for_new_val
bool – Indicates whether the counter is ready for new continuous pulse train values.
co_usb_xfer_req_count
int – Specifies the maximum number of simultaneous USB transfers used to stream data. Modify this value
to affect performance under different combinations of operating system and device.
co_usb_xfer_req_size
int – Specifies the maximum size of a USB transfer request in bytes. Modify this value to affect performance under different combinations of operating system and device.
co_use_only_on_brd_mem
bool – Specifies whether to write samples directly to the onboard memory of the device, bypassing the
memory buffer. Generally, you cannot update onboard memory directly after you start the task. Onboard
memory includes data FIFOs.
description
str – Specifies a user-defined description for the channel.
is_global
bool – Indicates whether the channel is a global channel.
name
str – Specifies the name of the virtual channel this object represents.
physical_channel
nidaqmx.system.physical_channel.PhysicalChannel – Specifies the name of the physical channel upon which this virtual channel is based.

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save(save_as=u’‘, author=u’‘, overwrite_existing_channel=False, allow_interactive_editing=True, allow_interactive_deletion=True)
Saves this local or global channel to MAX as a global channel.
Parameters
• save_as (Optional[str]) – Is the name to save the task, global channel, or custom
scale as. If you do not specify a value for this input, NI-DAQmx uses the name currently
assigned to the task, global channel, or custom scale.
• author (Optional[str]) – Is a name to store with the task, global channel, or custom
scale.
• overwrite_existing_channel (Optional[bool]) – Specifies whether to
overwrite a global channel of the same name if one is already saved in MAX. If this input
is False and a global channel of the same name is already saved in MAX, this function
returns an error.
• allow_interactive_editing (Optional[bool]) – Specifies whether to allow the task, global channel, or custom scale to be edited in the DAQ Assistant. If allow_interactive_editing is True, the DAQ Assistant must support all task or global channel
settings.
• allow_interactive_deletion (Optional[bool]) – Specifies whether to allow the task, global channel, or custom scale to be deleted through MAX.
nidaqmx.task.di_channel
class nidaqmx._task_modules.channels.di_channel.DIChannel(task_handle,
virtual_or_physical_name)
Bases: nidaqmx._task_modules.channels.channel.Channel
Represents one or more digital input virtual channels and their properties.
chan_type
nidaqmx.constants.ChannelType – Indicates the type of the virtual channel.
channel_names
List[str] – Specifies the unflattened list of the virtual channels.
description
str – Specifies a user-defined description for the channel.
di_acquire_on
nidaqmx.constants.ActiveOrInactiveEdgeSelection – Specifies on which edge of the
sample clock to acquire samples.
di_data_xfer_mech
nidaqmx.constants.DataTransferActiveTransferMode – Specifies the data transfer mode
for the device.
di_data_xfer_req_cond
nidaqmx.constants.InputDataTransferCondition – Specifies under what condition to
transfer data from the onboard memory of the device to the buffer.
di_dig_fltr_enable
bool – Specifies whether to enable the digital filter for the line(s) or port(s). You can enable the filter on a
line-by- line basis. You do not have to enable the filter for all lines in a channel.

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di_dig_fltr_enable_bus_mode
bool – Specifies whether to enable bus mode for digital filtering. If you set this property to True, NIDAQmx treats all lines that use common filtering settings as a bus. If any line in the bus has jitter, all lines
in the bus hold state until the entire bus stabilizes, or until 2 times the minimum pulse width elapses. If you
set this property to False, NI-DAQmx filters all lines individually. Jitter in one line does not affect other
lines.
di_dig_fltr_min_pulse_width
float – Specifies in seconds the minimum pulse width the filter recognizes as a valid high or low state
transition.
di_dig_fltr_timebase_rate
float – Specifies in hertz the rate of the digital filter timebase. NI-DAQmx uses this value to compute
settings for the filter.
di_dig_fltr_timebase_src
str – Specifies the terminal of the signal to use as the timebase of the digital filter.
di_dig_sync_enable
bool – Specifies whether to synchronize recognition of transitions in the signal to the internal timebase of
the device.
di_invert_lines
bool – Specifies whether to invert the lines in the channel. If you set this property to True, the lines are at
high logic when off and at low logic when on.
di_logic_family
nidaqmx.constants.LogicFamily – Specifies the logic family to use for acquisition. A logic
family corresponds to voltage thresholds that are compatible with a group of voltage standards. Refer to
the device documentation for information on the logic high and logic low voltages for these logic families.
di_mem_map_enable
bool – Specifies for NI-DAQmx to map hardware registers to the memory space of the application, if possible. Normally, NI- DAQmx maps hardware registers to memory accessible only to the kernel. Mapping
the registers to the memory space of the application increases performance. However, if the application
accesses the memory space mapped to the registers, it can adversely affect the operation of the device and
possibly result in a system crash.
di_num_lines
int – Indicates the number of digital lines in the channel.
di_tristate
bool – Specifies whether to tristate the lines in the channel. If you set this property to True, NI-DAQmx
tristates the lines in the channel. If you set this property to False, NI-DAQmx does not modify the configuration of the lines even if the lines were previously tristated. Set this property to False to read lines in
other tasks or to read output-only lines.
di_usb_xfer_req_count
int – Specifies the maximum number of simultaneous USB transfers used to stream data. Modify this value
to affect performance under different combinations of operating system and device.
di_usb_xfer_req_size
int – Specifies the maximum size of a USB transfer request in bytes. Modify this value to affect performance under different combinations of operating system and device.
is_global
bool – Indicates whether the channel is a global channel.
name
str – Specifies the name of the virtual channel this object represents.

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physical_channel
nidaqmx.system.physical_channel.PhysicalChannel – Specifies the name of the physical channel upon which this virtual channel is based.
save(save_as=u’‘, author=u’‘, overwrite_existing_channel=False, allow_interactive_editing=True, allow_interactive_deletion=True)
Saves this local or global channel to MAX as a global channel.
Parameters
• save_as (Optional[str]) – Is the name to save the task, global channel, or custom
scale as. If you do not specify a value for this input, NI-DAQmx uses the name currently
assigned to the task, global channel, or custom scale.
• author (Optional[str]) – Is a name to store with the task, global channel, or custom
scale.
• overwrite_existing_channel (Optional[bool]) – Specifies whether to
overwrite a global channel of the same name if one is already saved in MAX. If this input
is False and a global channel of the same name is already saved in MAX, this function
returns an error.
• allow_interactive_editing (Optional[bool]) – Specifies whether to allow the task, global channel, or custom scale to be edited in the DAQ Assistant. If allow_interactive_editing is True, the DAQ Assistant must support all task or global channel
settings.
• allow_interactive_deletion (Optional[bool]) – Specifies whether to allow the task, global channel, or custom scale to be deleted through MAX.
nidaqmx.task.do_channel
class nidaqmx._task_modules.channels.do_channel.DOChannel(task_handle,
virtual_or_physical_name)
Bases: nidaqmx._task_modules.channels.channel.Channel
Represents one or more digital output virtual channels and their properties.
chan_type
nidaqmx.constants.ChannelType – Indicates the type of the virtual channel.
channel_names
List[str] – Specifies the unflattened list of the virtual channels.
description
str – Specifies a user-defined description for the channel.
do_data_xfer_mech
nidaqmx.constants.DataTransferActiveTransferMode – Specifies the data transfer mode
for the device.
do_data_xfer_req_cond
nidaqmx.constants.OutputDataTransferCondition – Specifies under what condition to
transfer data from the buffer to the onboard memory of the device.
do_generate_on
nidaqmx.constants.ActiveOrInactiveEdgeSelection – Specifies on which edge of the
sample clock to generate samples.

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do_invert_lines
bool – Specifies whether to invert the lines in the channel. If you set this property to True, the lines are at
high logic when off and at low logic when on.
do_line_states_done_state
nidaqmx.constants.Level – Specifies the state of the lines in a digital output task when the task
completes execution.
do_line_states_paused_state
nidaqmx.constants.Level – Specifies the state of the lines in a digital output task when the task
pauses.
do_line_states_start_state
nidaqmx.constants.Level – Specifies the state of the lines in a digital output task when the task
starts.
do_logic_family
nidaqmx.constants.LogicFamily – Specifies the logic family to use for generation. A logic
family corresponds to voltage thresholds that are compatible with a group of voltage standards. Refer to
the device documentation for information on the logic high and logic low voltages for these logic families.
do_mem_map_enable
bool – Specifies for NI-DAQmx to map hardware registers to the memory space of the application, if possible. Normally, NI- DAQmx maps hardware registers to memory accessible only to the kernel. Mapping
the registers to the memory space of the application increases performance. However, if the application
accesses the memory space mapped to the registers, it can adversely affect the operation of the device and
possibly result in a system crash.
do_num_lines
int – Indicates the number of digital lines in the channel.
do_output_drive_type
nidaqmx.constants.DigitalDriveType – Specifies the drive type for digital output channels.
do_overcurrent_auto_reenable
bool – Specifies whether to automatically reenable channels after they no longer exceed the current limit
specified by do_overcurrent_limit.
do_overcurrent_limit
float – Specifies the current threshold in Amperes for the channel. A value of 0 means the channel observes
no limit. Devices can monitor only a finite number of current thresholds simultaneously. If you attempt to
monitor additional thresholds, NI-DAQmx returns an error.
do_overcurrent_reenable_period
float – Specifies the delay in seconds between the time a channel no longer exceeds the current limit and
the reactivation of that channel, if do_overcurrent_auto_reenable is True.
do_tristate
bool – Specifies whether to stop driving the channel and set it to a high-impedance state. You must commit
the task for this setting to take effect.
do_usb_xfer_req_count
int – Specifies the maximum number of simultaneous USB transfers used to stream data. Modify this value
to affect performance under different combinations of operating system and device.
do_usb_xfer_req_size
int – Specifies the maximum size of a USB transfer request in bytes. Modify this value to affect performance under different combinations of operating system and device.
do_use_only_on_brd_mem
bool – Specifies whether to write samples directly to the onboard memory of the device, bypassing the

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memory buffer. Generally, you cannot update onboard memory after you start the task. Onboard memory
includes data FIFOs.
is_global
bool – Indicates whether the channel is a global channel.
name
str – Specifies the name of the virtual channel this object represents.
physical_channel
nidaqmx.system.physical_channel.PhysicalChannel – Specifies the name of the physical channel upon which this virtual channel is based.
save(save_as=u’‘, author=u’‘, overwrite_existing_channel=False, allow_interactive_editing=True, allow_interactive_deletion=True)
Saves this local or global channel to MAX as a global channel.
Parameters
• save_as (Optional[str]) – Is the name to save the task, global channel, or custom
scale as. If you do not specify a value for this input, NI-DAQmx uses the name currently
assigned to the task, global channel, or custom scale.
• author (Optional[str]) – Is a name to store with the task, global channel, or custom
scale.
• overwrite_existing_channel (Optional[bool]) – Specifies whether to
overwrite a global channel of the same name if one is already saved in MAX. If this input
is False and a global channel of the same name is already saved in MAX, this function
returns an error.
• allow_interactive_editing (Optional[bool]) – Specifies whether to allow the task, global channel, or custom scale to be edited in the DAQ Assistant. If allow_interactive_editing is True, the DAQ Assistant must support all task or global channel
settings.
• allow_interactive_deletion (Optional[bool]) – Specifies whether to allow the task, global channel, or custom scale to be deleted through MAX.

nidaqmx.task.channel_collection
class nidaqmx._task_modules.channel_collection.ChannelCollection(task_handle)
Bases: _abcoll.Sequence
Contains the collection of channels for a DAQmx Task.
This class defines methods that implements a container object.
all
nidaqmx._task_modules.channels.channel.Channel – Specifies a channel object that represents the entire list of virtual channels on this channel collection.
channel_names
List[str] – Specifies the entire list of virtual channels on this channel collection.
nidaqmx.task.ai_channel_collection
class nidaqmx._task_modules.ai_channel_collection.AIChannelCollection(task_handle)
Bases: nidaqmx._task_modules.channel_collection.ChannelCollection

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Contains the collection of analog input channels for a DAQmx Task.
add_ai_accel_4_wire_dc_voltage_chan(physical_channel, name_to_assign_to_channel=u’‘,
terminal_config=,
min_val=-5.0,
max_val=5.0,
units=,
sensitivity=1000.0,
sensitivity_units=, voltage_excit_source=,
voltage_excit_val=0.0,
use_excit_for_scaling=False,
custom_scale_name=u’‘)
Creates channel(s) to measure acceleration. Use this instance for custom sensors that require excitation.
You can use the excitation to scale the measurement.
Parameters
• physical_channel (str) – Specifies the names of the physical channels to use to
create virtual channels. The DAQmx physical channel constant lists all physical channels
on devices and modules installed in the system.
• name_to_assign_to_channel (Optional[str]) – Specifies a name to assign
to the virtual channel this function creates. If you do not specify a value for this input,
NI-DAQmx uses the physical channel name as the virtual channel name.
• terminal_config
(Optional[nidaqmx.constants.
TerminalConfiguration]) – Specifies the input terminal configuration for
the channel.
• min_val (Optional[float]) – Specifies in units the minimum value you expect to
measure.
• max_val (Optional[float]) – Specifies in units the maximum value you expect to
measure.
• units (Optional[nidaqmx.constants.AccelUnits]) – Specifies the units to
use to return acceleration measurements from the channel.
• sensitivity (Optional[float]) – Is the sensitivity of the sensor. This value is in
the units you specify with the sensitivity_units input. Refer to the sensor documentation
to determine this value.
• sensitivity_units
(Optional[nidaqmx.constants.
AccelSensitivityUnits]) – Specifies the units of the sensitivity input.
• voltage_excit_source
(Optional[nidaqmx.constants.
ExcitationSource]) – Specifies the source of excitation.
• voltage_excit_val (Optional[float]) – Specifies in volts the amount of excitation supplied to the sensor. Refer to the sensor documentation to determine appropriate
excitation values.
• use_excit_for_scaling (Optional[bool]) – Specifies if NI- DAQmx divides
the measurement by the excitation. You should typically set use_excit_for_scaling to
True for ratiometric transducers. If you set use_excit_for_scaling to True, set max_val
and min_val to reflect the scaling.
• custom_scale_name (Optional[str]) – Specifies the name of a custom scale for
the channel. If you want the channel to use a custom scale, specify the name of the custom
scale to this input and set units to FROM_CUSTOM_SCALE.
Returns Indicates the newly created channel object.
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Return type nidaqmx._task_modules.channels.ai_channel.AIChannel
add_ai_accel_chan(physical_channel,
name_to_assign_to_channel=u’‘,
terminal_config=,
min_val=-5.0,
max_val=5.0, units=, sensitivity=1000.0, sensitivity_units=,
current_excit_source=,
current_excit_val=0.004, custom_scale_name=u’‘)
Creates channel(s) that use an accelerometer to measure acceleration.
Parameters
• physical_channel (str) – Specifies the names of the physical channels to use to
create virtual channels. The DAQmx physical channel constant lists all physical channels
on devices and modules installed in the system.
• name_to_assign_to_channel (Optional[str]) – Specifies a name to assign
to the virtual channel this function creates. If you do not specify a value for this input,
NI-DAQmx uses the physical channel name as the virtual channel name.
• terminal_config
(Optional[nidaqmx.constants.
TerminalConfiguration]) – Specifies the input terminal configuration for
the channel.
• min_val (Optional[float]) – Specifies in units the minimum value you expect to
measure.
• max_val (Optional[float]) – Specifies in units the maximum value you expect to
measure.
• units (Optional[nidaqmx.constants.AccelUnits]) – Specifies the units to
use to return acceleration measurements from the channel.
• sensitivity (Optional[float]) – Is the sensitivity of the sensor. This value is in
the units you specify with the sensitivity_units input. Refer to the sensor documentation
to determine this value.
• sensitivity_units
(Optional[nidaqmx.constants.
AccelSensitivityUnits]) – Specifies the units of the sensitivity input.
• current_excit_source
(Optional[nidaqmx.constants.
ExcitationSource]) – Specifies the source of excitation.
• current_excit_val (Optional[float]) – Specifies in amperes the amount of
excitation to supply to the sensor. Refer to the sensor documentation to determine this
value.
• custom_scale_name (Optional[str]) – Specifies the name of a custom scale for
the channel. If you want the channel to use a custom scale, specify the name of the custom
scale to this input and set units to FROM_CUSTOM_SCALE.
Returns Indicates the newly created channel object.
Return type nidaqmx._task_modules.channels.ai_channel.AIChannel
add_ai_accel_charge_chan(physical_channel,
name_to_assign_to_channel=u’‘,
terminal_config=,
min_val=-5.0,
max_val=5.0,
units=,
sensitivity=100.0,
sensitivity_units=, custom_scale_name=u’‘)
Creates channel(s) that use a charge-based sensor to measure acceleration.

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Parameters
• physical_channel (str) – Specifies the names of the physical channels to use to
create virtual channels. The DAQmx physical channel constant lists all physical channels
on devices and modules installed in the system.
• name_to_assign_to_channel (Optional[str]) – Specifies a name to assign
to the virtual channel this function creates. If you do not specify a value for this input,
NI-DAQmx uses the physical channel name as the virtual channel name.
• terminal_config
(Optional[nidaqmx.constants.
TerminalConfiguration]) – Specifies the input terminal configuration for
the channel.
• min_val (Optional[float]) – Specifies in units the minimum value you expect to
measure.
• max_val (Optional[float]) – Specifies in units the maximum value you expect to
measure.
• units (Optional[nidaqmx.constants.AccelUnits]) – Specifies the units to
use to return acceleration measurements from the channel.
• sensitivity (Optional[float]) – Is the sensitivity of the sensor. This value is in
the units you specify with the sensitivity_units input. Refer to the sensor documentation
to determine this value.
• sensitivity_units
(Optional[nidaqmx.constants.
AccelChargeSensitivityUnits]) – Specifies the units of the sensitivity
input.
• custom_scale_name (Optional[str]) – Specifies the name of a custom scale for
the channel. If you want the channel to use a custom scale, specify the name of the custom
scale to this input and set units to FROM_CUSTOM_SCALE.
Returns Indicates the newly created channel object.
Return type nidaqmx._task_modules.channels.ai_channel.AIChannel
add_ai_bridge_chan(physical_channel,
name_to_assign_to_channel=u’‘,
min_val=0.002,
max_val=0.002,
units=,
bridge_config=, voltage_excit_source=,
voltage_excit_val=2.5,
nominal_bridge_resistance=350.0,
custom_scale_name=u’‘)
Creates channel(s) that measure voltage ratios from a Wheatstone bridge. Use this instance with bridgebased sensors that measure phenomena other than strain, force, pressure, or torque, or that scale data to
physical units NI-DAQmx does not support.
Parameters
• physical_channel (str) – Specifies the names of the physical channels to use to
create virtual channels. The DAQmx physical channel constant lists all physical channels
on devices and modules installed in the system.
• name_to_assign_to_channel (Optional[str]) – Specifies a name to assign
to the virtual channel this function creates. If you do not specify a value for this input,
NI-DAQmx uses the physical channel name as the virtual channel name.
• min_val (Optional[float]) – Specifies in units the minimum value you expect to
measure.

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• max_val (Optional[float]) – Specifies in units the maximum value you expect to
measure.
• units (Optional[nidaqmx.constants.BridgeUnits]) – Specifies in which
unit to return voltage ratios from the channel.
• bridge_config
(Optional[nidaqmx.constants.
BridgeConfiguration]) – Specifies information about the bridge configuration and
measurement.
• voltage_excit_source
(Optional[nidaqmx.constants.
ExcitationSource]) – Specifies information about the bridge configuration
and measurement.
• voltage_excit_val (Optional[float]) – Specifies information about the
bridge configuration and measurement.
• nominal_bridge_resistance (Optional[float]) – Specifies information
about the bridge configuration and measurement.
• custom_scale_name (Optional[str]) – Specifies the name of a custom scale for
the channel. If you want the channel to use a custom scale, specify the name of the custom
scale to this input and set units to FROM_CUSTOM_SCALE.
Returns Indicates the newly created channel object.
Return type nidaqmx._task_modules.channels.ai_channel.AIChannel
add_ai_charge_chan(physical_channel,
name_to_assign_to_channel=u’‘,
terminal_config=,
min_val=-1e-09,
max_val=1e-09,
units=,
custom_scale_name=u’‘)
Creates channel(s) that use a sensor with charge output.
Parameters
• physical_channel (str) – Specifies the names of the physical channels to use to
create virtual channels. The DAQmx physical channel constant lists all physical channels
on devices and modules installed in the system.
• name_to_assign_to_channel (Optional[str]) – Specifies a name to assign
to the virtual channel this function creates. If you do not specify a value for this input,
NI-DAQmx uses the physical channel name as the virtual channel name.
• terminal_config
(Optional[nidaqmx.constants.
TerminalConfiguration]) – Specifies the input terminal configuration for
the channel.
• min_val (Optional[float]) – Specifies in units the minimum value you expect to
measure.
• max_val (Optional[float]) – Specifies in units the maximum value you expect to
measure.
• units (Optional[nidaqmx.constants.ChargeUnits]) – Specifies the units
to use to return charge measurements from the channel.
• custom_scale_name (Optional[str]) – Specifies the name of a custom scale for
the channel. If you want the channel to use a custom scale, specify the name of the custom
scale to this input and set units to FROM_CUSTOM_SCALE.
Returns Indicates the newly created channel object.
Return type nidaqmx._task_modules.channels.ai_channel.AIChannel
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add_ai_current_chan(physical_channel,
name_to_assign_to_channel=u’‘,
terminal_config=,
min_val=0.01,
max_val=0.01,
units=,
shunt_resistor_loc=, ext_shunt_resistor_val=249.0, custom_scale_name=u’‘)
Creates channel(s) to measure current.
Parameters
• physical_channel (str) – Specifies the names of the physical channels to use to
create virtual channels. The DAQmx physical channel constant lists all physical channels
on devices and modules installed in the system.
• name_to_assign_to_channel (Optional[str]) – Specifies a name to assign
to the virtual channel this function creates. If you do not specify a value for this input,
NI-DAQmx uses the physical channel name as the virtual channel name.
• terminal_config
(Optional[nidaqmx.constants.
TerminalConfiguration]) – Specifies the input terminal configuration for
the channel.
• min_val (Optional[float]) – Specifies in units the minimum value you expect to
measure.
• max_val (Optional[float]) – Specifies in units the maximum value you expect to
measure.
• units (Optional[nidaqmx.constants.CurrentUnits]) – Specifies the
units to use to return current measurements.
• shunt_resistor_loc
(Optional[nidaqmx.constants.
CurrentShuntResistorLocation]) – Specifies the location of the shunt
resistor. For devices with built-in shunt resistors, specify the location as INTERNAL.
For devices that do not have built-in shunt resistors, you must attach an external one, set
this input to EXTERNAL and use the ext_shunt_resistor_val input to specify the value
of the resistor.
• ext_shunt_resistor_val (Optional[float]) – Specifies in ohms the resistance of an external shunt resistor.
• custom_scale_name (Optional[str]) – Specifies the name of a custom scale for
the channel. If you want the channel to use a custom scale, specify the name of the custom
scale to this input and set units to FROM_CUSTOM_SCALE.
Returns Indicates the newly created channel object.
Return type nidaqmx._task_modules.channels.ai_channel.AIChannel
add_ai_current_rms_chan(physical_channel,
name_to_assign_to_channel=u’‘,
terminal_config=, min_val=0.01,
max_val=0.01,
units=,
shunt_resistor_loc=, ext_shunt_resistor_val=249.0, custom_scale_name=u’‘)
Creates a channel to measure current RMS, the average (mean) power of the acquired current.
Parameters
• physical_channel (str) – Specifies the names of the physical channels to use to
create virtual channels. The DAQmx physical channel constant lists all physical channels
on devices and modules installed in the system.

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• name_to_assign_to_channel (Optional[str]) – Specifies a name to assign
to the virtual channel this function creates. If you do not specify a value for this input,
NI-DAQmx uses the physical channel name as the virtual channel name.
• terminal_config
(Optional[nidaqmx.constants.
TerminalConfiguration]) – Specifies the input terminal configuration for
the channel.
• min_val (Optional[float]) – Specifies in units the minimum value you expect to
measure.
• max_val (Optional[float]) – Specifies in units the maximum value you expect to
measure.
• units (Optional[nidaqmx.constants.CurrentUnits]) – Specifies the
units to use to return current measurements.
• shunt_resistor_loc
(Optional[nidaqmx.constants.
CurrentShuntResistorLocation]) – Specifies the location of the shunt
resistor. For devices with built-in shunt resistors, specify the location as INTERNAL.
For devices that do not have built-in shunt resistors, you must attach an external one, set
this input to EXTERNAL and use the ext_shunt_resistor_val input to specify the value
of the resistor.
• ext_shunt_resistor_val (Optional[float]) – Specifies in ohms the resistance of an external shunt resistor.
• custom_scale_name (Optional[str]) – Specifies the name of a custom scale for
the channel. If you want the channel to use a custom scale, specify the name of the custom
scale to this input and set units to FROM_CUSTOM_SCALE.
Returns Indicates the newly created channel object.
Return type nidaqmx._task_modules.channels.ai_channel.AIChannel
add_ai_force_bridge_polynomial_chan(physical_channel, name_to_assign_to_channel=u’‘,
min_val=-100.0,
max_val=100.0,
units=,
bridge_config=, voltage_excit_source=,
voltage_excit_val=2.5,
nominal_bridge_resistance=350.0,
forward_coeffs=None, reverse_coeffs=None, electrical_units=, physical_units=, custom_scale_name=u’‘)
Creates channel(s) that use a Wheatstone bridge to measure force or load. Use this instance with sensors
whose specifications provide a polynomial to convert electrical values to physical values. When you
use this scaling type, NI-DAQmx requires coefficients for a polynomial that converts electrical values to
physical values (forward), as well as coefficients for a polynomial that converts physical values to electrical
values (reverse). If you only know one set of coefficients, use the DAQmx Compute Reverse Polynomial
Coefficients function to generate the other set.
Parameters
• physical_channel (str) – Specifies the names of the physical channels to use to
create virtual channels. The DAQmx physical channel constant lists all physical channels
on devices and modules installed in the system.
• name_to_assign_to_channel (Optional[str]) – Specifies a name to assign
to the virtual channel this function creates. If you do not specify a value for this input,
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NI-DAQmx uses the physical channel name as the virtual channel name.
• min_val (Optional[float]) – Specifies in units the minimum value you expect to
measure.
• max_val (Optional[float]) – Specifies in units the maximum value you expect to
measure.
• units (Optional[nidaqmx.constants.ForceUnits]) – Specifies in which
unit to return force measurements from the channel.
• bridge_config
(Optional[nidaqmx.constants.
BridgeConfiguration]) – Specifies information about the bridge configuration and
measurement.
• voltage_excit_source
(Optional[nidaqmx.constants.
ExcitationSource]) – Specifies information about the bridge configuration
and measurement.
• voltage_excit_val (Optional[float]) – Specifies information about the
bridge configuration and measurement.
• nominal_bridge_resistance (Optional[float]) – Specifies information
about the bridge configuration and measurement.
• forward_coeffs (Optional[List[float]]) – Specifies how to scale electrical
values from the sensor to physical units.
• reverse_coeffs (Optional[List[float]]) – Specifies how to scale electrical
values from the sensor to physical units.
• electrical_units
(Optional[nidaqmx.constants.
BridgeElectricalUnits]) – Specifies how to scale electrical values from
the sensor to physical units.
• physical_units
(Optional[nidaqmx.constants.
BridgePhysicalUnits]) – Specifies how to scale electrical values from the
sensor to physical units.
• custom_scale_name (Optional[str]) – Specifies the name of a custom scale for
the channel. If you want the channel to use a custom scale, specify the name of the custom
scale to this input and set units to FROM_CUSTOM_SCALE.
Returns Indicates the newly created channel object.
Return type nidaqmx._task_modules.channels.ai_channel.AIChannel
add_ai_force_bridge_table_chan(physical_channel,
name_to_assign_to_channel=u’‘,
min_val=-100.0,
max_val=100.0,
units=,
bridge_config=, voltage_excit_source=,
voltage_excit_val=2.5,
nominal_bridge_resistance=350.0,
electrical_vals=None,
electrical_units=,
physical_vals=None,
physical_units=,
custom_scale_name=u’‘)
Creates channel(s) that use a Wheatstone bridge to measure force or load. Use this instance with sensors
whose specifications provide a table of electrical values and the corresponding physical values. When
you use this scaling type, NI-DAQmx performs linear scaling between each pair of electrical and physical
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values. The input limits specified with min_val and max_val must fall within the smallest and largest
physical values. For any data outside those endpoints, NI-DAQmx coerces that data to the endpoints.
Parameters
• physical_channel (str) – Specifies the names of the physical channels to use to
create virtual channels. The DAQmx physical channel constant lists all physical channels
on devices and modules installed in the system.
• name_to_assign_to_channel (Optional[str]) – Specifies a name to assign
to the virtual channel this function creates. If you do not specify a value for this input,
NI-DAQmx uses the physical channel name as the virtual channel name.
• min_val (Optional[float]) – Specifies in units the minimum value you expect to
measure.
• max_val (Optional[float]) – Specifies in units the maximum value you expect to
measure.
• units (Optional[nidaqmx.constants.ForceUnits]) – Specifies in which
unit to return force measurements from the channel.
• bridge_config
(Optional[nidaqmx.constants.
BridgeConfiguration]) – Specifies information about the bridge configuration and
measurement.
• voltage_excit_source
(Optional[nidaqmx.constants.
ExcitationSource]) – Specifies information about the bridge configuration
and measurement.
• voltage_excit_val (Optional[float]) – Specifies information about the
bridge configuration and measurement.
• nominal_bridge_resistance (Optional[float]) – Specifies information
about the bridge configuration and measurement.
• electrical_vals (Optional[List[float]]) – Specifies how to scale electrical values from the sensor to physical units.
• electrical_units
(Optional[nidaqmx.constants.
BridgeElectricalUnits]) – Specifies how to scale electrical values from
the sensor to physical units.
• physical_vals (Optional[List[float]]) – Specifies how to scale electrical
values from the sensor to physical units.
• physical_units
(Optional[nidaqmx.constants.
BridgePhysicalUnits]) – Specifies how to scale electrical values from the
sensor to physical units.
• custom_scale_name (Optional[str]) – Specifies the name of a custom scale for
the channel. If you want the channel to use a custom scale, specify the name of the custom
scale to this input and set units to FROM_CUSTOM_SCALE.
Returns Indicates the newly created channel object.
Return type nidaqmx._task_modules.channels.ai_channel.AIChannel

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add_ai_force_bridge_two_point_lin_chan(physical_channel,
name_to_assign_to_channel=u’‘,
min_val=-100.0,
max_val=100.0,
units=,
bridge_config=,
voltage_excit_source=,
voltage_excit_val=2.5,
nominal_bridge_resistance=350.0,
first_electrical_val=0.0,
second_electrical_val=2.0,
electrical_units=,
first_physical_val=0.0,
second_physical_val=100.0,
physical_units=, custom_scale_name=u’‘)
Creates channel(s) that use a Wheatstone bridge to measure force or load. Use this instance with sensors
whose specifications do not provide a polynomial for scaling or a table of electrical and physical values.
When you use this scaling type, NI-DAQmx uses two points of electrical and physical values to calculate
the slope and y-intercept of a linear equation and uses that equation to scale electrical values to physical
values.
Parameters
• physical_channel (str) – Specifies the names of the physical channels to use to
create virtual channels. The DAQmx physical channel constant lists all physical channels
on devices and modules installed in the system.
• name_to_assign_to_channel (Optional[str]) – Specifies a name to assign
to the virtual channel this function creates. If you do not specify a value for this input,
NI-DAQmx uses the physical channel name as the virtual channel name.
• min_val (Optional[float]) – Specifies in units the minimum value you expect to
measure.
• max_val (Optional[float]) – Specifies in units the maximum value you expect to
measure.
• units (Optional[nidaqmx.constants.ForceUnits]) – Specifies in which
unit to return force measurements from the channel.
• bridge_config
(Optional[nidaqmx.constants.
BridgeConfiguration]) – Specifies information about the bridge configuration and
measurement.
• voltage_excit_source
(Optional[nidaqmx.constants.
ExcitationSource]) – Specifies information about the bridge configuration
and measurement.
• voltage_excit_val (Optional[float]) – Specifies information about the
bridge configuration and measurement.
• nominal_bridge_resistance (Optional[float]) – Specifies information
about the bridge configuration and measurement.
• first_electrical_val (Optional[float]) – Specifies how to scale electrical
values from the sensor to physical units.
• second_electrical_val (Optional[float]) – Specifies how to scale electrical values from the sensor to physical units.

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• electrical_units
(Optional[nidaqmx.constants.
BridgeElectricalUnits]) – Specifies how to scale electrical values from
the sensor to physical units.
• first_physical_val (Optional[float]) – Specifies how to scale electrical values from the sensor to physical units.
• second_physical_val (Optional[float]) – Specifies how to scale electrical
values from the sensor to physical units.
• physical_units
(Optional[nidaqmx.constants.
BridgePhysicalUnits]) – Specifies how to scale electrical values from the
sensor to physical units.
• custom_scale_name (Optional[str]) – Specifies the name of a custom scale for
the channel. If you want the channel to use a custom scale, specify the name of the custom
scale to this input and set units to FROM_CUSTOM_SCALE.
Returns Indicates the newly created channel object.
Return type nidaqmx._task_modules.channels.ai_channel.AIChannel
add_ai_force_iepe_chan(physical_channel,
name_to_assign_to_channel=u’‘,
terminal_config=,
min_val=-2000.0,
max_val=2000.0,
units=, sensitivity=2.25, sensitivity_units=,
current_excit_source=, current_excit_val=0.004, custom_scale_name=u’‘)
Creates channel(s) that use an IEPE force sensor to measure force or load.
Parameters
• physical_channel (str) – Specifies the names of the physical channels to use to
create virtual channels. The DAQmx physical channel constant lists all physical channels
on devices and modules installed in the system.
• name_to_assign_to_channel (Optional[str]) – Specifies a name to assign
to the virtual channel this function creates. If you do not specify a value for this input,
NI-DAQmx uses the physical channel name as the virtual channel name.
• terminal_config
(Optional[nidaqmx.constants.
TerminalConfiguration]) – Specifies the input terminal configuration for
the channel.
• min_val (Optional[float]) – Specifies in units the minimum value you expect to
measure.
• max_val (Optional[float]) – Specifies in units the maximum value you expect to
measure.
• units (Optional[nidaqmx.constants.ForceUnits]) – Specifies in which
unit to return force measurements from the channel.
• sensitivity (Optional[float]) – Is the sensitivity of the sensor. This value is in
the units you specify with the sensitivity_units input. Refer to the sensor documentation
to determine this value.
• sensitivity_units
(Optional[nidaqmx.constants.
ForceIEPESensorSensitivityUnits]) – Specifies the units of the sensitivity
input.

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• current_excit_source
(Optional[nidaqmx.constants.
ExcitationSource]) – Specifies the source of excitation.
• current_excit_val (Optional[float]) – Specifies in amperes the amount of
excitation to supply to the sensor. Refer to the sensor documentation to determine this
value.
• custom_scale_name (Optional[str]) – Specifies the name of a custom scale for
the channel. If you want the channel to use a custom scale, specify the name of the custom
scale to this input and set units to FROM_CUSTOM_SCALE.
Returns Indicates the newly created channel object.
Return type nidaqmx._task_modules.channels.ai_channel.AIChannel
add_ai_freq_voltage_chan(physical_channel, name_to_assign_to_channel=u’‘, min_val=1,
max_val=100, units=, threshold_level=0.0, hysteresis=0.0, custom_scale_name=u’‘)
Creates channel(s) that use a frequency-to-voltage converter to measure frequency.
Parameters
• physical_channel (str) – Specifies the names of the physical channels to use to
create virtual channels. The DAQmx physical channel constant lists all physical channels
on devices and modules installed in the system.
• name_to_assign_to_channel (Optional[str]) – Specifies a name to assign
to the virtual channel this function creates. If you do not specify a value for this input,
NI-DAQmx uses the physical channel name as the virtual channel name.
• min_val (Optional[float]) – Specifies in units the minimum value you expect to
measure.
• max_val (Optional[float]) – Specifies in units the maximum value you expect to
measure.
• units (Optional[nidaqmx.constants.FrequencyUnits]) – Specifies the
units to use to return frequency measurements.
• threshold_level (Optional[float]) – Specifies in volts the level at which to
recognize waveform repetitions. You should select a voltage level that occurs only once
within the entire period of a waveform. You also can select a voltage that occurs only once
while the voltage rises or falls.
• hysteresis (Optional[float]) – Specifies in volts a window below level. The
input voltage must pass below threshold_level minus hysteresis before NI-DAQmx recognizes a waveform repetition. Hysteresis can improve measurement accuracy when the
signal contains noise or jitter.
• custom_scale_name (Optional[str]) – Specifies the name of a custom scale for
the channel. If you want the channel to use a custom scale, specify the name of the custom
scale to this input and set units to FROM_CUSTOM_SCALE.
Returns Indicates the newly created channel object.
Return type nidaqmx._task_modules.channels.ai_channel.AIChannel
add_ai_microphone_chan(physical_channel,
name_to_assign_to_channel=u’‘,
terminal_config=,
units=,
mic_sensitivity=10.0,
max_snd_press_level=100.0,
current_excit_source=,
current_excit_val=0.004, custom_scale_name=u’‘)
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Creates channel(s) that use a microphone to measure sound pressure.
Parameters
• physical_channel (str) – Specifies the names of the physical channels to use to
create virtual channels. The DAQmx physical channel constant lists all physical channels
on devices and modules installed in the system.
• name_to_assign_to_channel (Optional[str]) – Specifies a name to assign
to the virtual channel this function creates. If you do not specify a value for this input,
NI-DAQmx uses the physical channel name as the virtual channel name.
• terminal_config
(Optional[nidaqmx.constants.
TerminalConfiguration]) – Specifies the input terminal configuration for
the channel.
• units (Optional[nidaqmx.constants.SoundPressureUnits]) – Specifies the units to use to return sound pressure measurements.
• mic_sensitivity (Optional[float]) – Is the sensitivity of the microphone.
Specify this value in mV/Pa.
• max_snd_press_level (Optional[float]) – Is the maximum instantaneous
sound pressure level you expect to measure. This value is in decibels, referenced to 20
micropascals.
• current_excit_source
(Optional[nidaqmx.constants.
ExcitationSource]) – Specifies the source of excitation.
• current_excit_val (Optional[float]) – Specifies in amperes the amount of
excitation to supply to the sensor. Refer to the sensor documentation to determine this
value.
• custom_scale_name (Optional[str]) – Specifies the name of a custom scale for
the channel. If you want the channel to use a custom scale, specify the name of the custom
scale to this input and set units to FROM_CUSTOM_SCALE.
Returns Indicates the newly created channel object.
Return type nidaqmx._task_modules.channels.ai_channel.AIChannel
add_ai_pos_eddy_curr_prox_probe_chan(physical_channel,
name_to_assign_to_channel=u’‘,
min_val=0.0,
max_val=0.00254,
units=,
sensitivity=200.0,
sensitivity_units=, custom_scale_name=u’‘)
Creates channel(s) that use an eddy current proximity probe to measure position.
Parameters
• physical_channel (str) – Specifies the names of the physical channels to use to
create virtual channels. The DAQmx physical channel constant lists all physical channels
on devices and modules installed in the system.
• name_to_assign_to_channel (Optional[str]) – Specifies a name to assign
to the virtual channel this function creates. If you do not specify a value for this input,
NI-DAQmx uses the physical channel name as the virtual channel name.
• min_val (Optional[float]) – Specifies in units the minimum value you expect to
measure.

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• max_val (Optional[float]) – Specifies in units the maximum value you expect to
measure.
• units (Optional[nidaqmx.constants.LengthUnits]) – Specifies the units
to use to return position measurements from the channel.
• sensitivity (Optional[float]) – Is the sensitivity of the sensor. This value is in
the units you specify with the sensitivity_units input. Refer to the sensor documentation
to determine this value.
• sensitivity_units
(Optional[nidaqmx.constants.
EddyCurrentProxProbeSensitivityUnits]) – Specifies the units of the
sensitivity input.
• custom_scale_name (Optional[str]) – Specifies the name of a custom scale for
the channel. If you want the channel to use a custom scale, specify the name of the custom
scale to this input and set units to FROM_CUSTOM_SCALE.
Returns Indicates the newly created channel object.
Return type nidaqmx._task_modules.channels.ai_channel.AIChannel
add_ai_pos_lvdt_chan(physical_channel,
name_to_assign_to_channel=u’‘,
min_val=-0.1,
max_val=0.1, units=, sensitivity=50.0,
sensitivity_units=,
voltage_excit_source=,
voltage_excit_val=1.0,
voltage_excit_freq=2500.0,
ac_excit_wire_mode=,
custom_scale_name=u’‘)
Creates channel(s) that use an LVDT to measure linear position.
Parameters
• physical_channel (str) – Specifies the names of the physical channels to use to
create virtual channels. The DAQmx physical channel constant lists all physical channels
on devices and modules installed in the system.
• name_to_assign_to_channel (Optional[str]) – Specifies a name to assign
to the virtual channel this function creates. If you do not specify a value for this input,
NI-DAQmx uses the physical channel name as the virtual channel name.
• min_val (Optional[float]) – Specifies in units the minimum value you expect to
measure.
• max_val (Optional[float]) – Specifies in units the maximum value you expect to
measure.
• units (Optional[nidaqmx.constants.LengthUnits]) – Specifies the units
to use to return linear position measurements from the channel.
• sensitivity (Optional[float]) – Is the sensitivity of the sensor. This value is in
the units you specify with the sensitivity_units input. Refer to the sensor documentation
to determine this value.
• sensitivity_units
(Optional[nidaqmx.constants.
LVDTSensitivityUnits]) – Specifies the units of the sensitivity input.
• voltage_excit_source
(Optional[nidaqmx.constants.
ExcitationSource]) – Specifies the source of excitation.
• voltage_excit_val (Optional[float]) – Specifies in volts the amount of excitation supplied to the sensor. Refer to the sensor documentation to determine appropriate
excitation values.
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• voltage_excit_freq (Optional[float]) – Specifies in hertz the excitation frequency that the sensor requires. Refer to the sensor documentation to determine this value.
• ac_excit_wire_mode
(Optional[nidaqmx.constants.
ACExcitWireMode]) – Is the number of leads on the sensor. Some sensors
require you to tie leads together to create a four- or five- wire sensor. Refer to the sensor
documentation for more information.
• custom_scale_name (Optional[str]) – Specifies the name of a custom scale for
the channel. If you want the channel to use a custom scale, specify the name of the custom
scale to this input and set units to FROM_CUSTOM_SCALE.
Returns Indicates the newly created channel object.
Return type nidaqmx._task_modules.channels.ai_channel.AIChannel
add_ai_pos_rvdt_chan(physical_channel, name_to_assign_to_channel=u’‘, min_val=-70.0,
max_val=70.0, units=, sensitivity=50.0,
sensitivity_units=,
voltage_excit_source=,
voltage_excit_val=1.0,
voltage_excit_freq=2500.0,
ac_excit_wire_mode=,
custom_scale_name=u’‘)
Creates channel(s) that use an RVDT to measure angular position.
Parameters
• physical_channel (str) – Specifies the names of the physical channels to use to
create virtual channels. The DAQmx physical channel constant lists all physical channels
on devices and modules installed in the system.
• name_to_assign_to_channel (Optional[str]) – Specifies a name to assign
to the virtual channel this function creates. If you do not specify a value for this input,
NI-DAQmx uses the physical channel name as the virtual channel name.
• min_val (Optional[float]) – Specifies in units the minimum value you expect to
measure.
• max_val (Optional[float]) – Specifies in units the maximum value you expect to
measure.
• units (Optional[nidaqmx.constants.AngleUnits]) – Specifies the units to
use to return angular position measurements from the channel.
• sensitivity (Optional[float]) – Is the sensitivity of the sensor. This value is in
the units you specify with the sensitivity_units input. Refer to the sensor documentation
to determine this value.
• sensitivity_units
(Optional[nidaqmx.constants.
RVDTSensitivityUnits]) – Specifies the units of the sensitivity input.
• voltage_excit_source
(Optional[nidaqmx.constants.
ExcitationSource]) – Specifies the source of excitation.
• voltage_excit_val (Optional[float]) – Specifies in volts the amount of excitation supplied to the sensor. Refer to the sensor documentation to determine appropriate
excitation values.
• voltage_excit_freq (Optional[float]) – Specifies in hertz the excitation frequency that the sensor requires. Refer to the sensor documentation to determine this value.
• ac_excit_wire_mode
(Optional[nidaqmx.constants.
ACExcitWireMode]) – Is the number of leads on the sensor. Some sensors
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require you to tie leads together to create a four- or five- wire sensor. Refer to the sensor
documentation for more information.
• custom_scale_name (Optional[str]) – Specifies the name of a custom scale for
the channel. If you want the channel to use a custom scale, specify the name of the custom
scale to this input and set units to FROM_CUSTOM_SCALE.
Returns Indicates the newly created channel object.
Return type nidaqmx._task_modules.channels.ai_channel.AIChannel
add_ai_pressure_bridge_polynomial_chan(physical_channel,
name_to_assign_to_channel=u’‘,
min_val=-100.0,
max_val=100.0,
units=, bridge_config=,
voltage_excit_source=,
voltage_excit_val=2.5,
nominal_bridge_resistance=350.0,
forward_coeffs=None,
reverse_coeffs=None,
electrical_units=,
physical_units=, custom_scale_name=u’‘)
Creates channel(s) that use a Wheatstone bridge to measure pressure. Use this instance with sensors
whose specifications provide a polynomial to convert electrical values to physical values. When you
use this scaling type, NI-DAQmx requires coefficients for a polynomial that converts electrical values to
physical values (forward), as well as coefficients for a polynomial that converts physical values to electrical
values (reverse). If you only know one set of coefficients, use the DAQmx Compute Reverse Polynomial
Coefficients function to generate the other set.
Parameters
• physical_channel (str) – Specifies the names of the physical channels to use to
create virtual channels. The DAQmx physical channel constant lists all physical channels
on devices and modules installed in the system.
• name_to_assign_to_channel (Optional[str]) – Specifies a name to assign
to the virtual channel this function creates. If you do not specify a value for this input,
NI-DAQmx uses the physical channel name as the virtual channel name.
• min_val (Optional[float]) – Specifies in units the minimum value you expect to
measure.
• max_val (Optional[float]) – Specifies in units the maximum value you expect to
measure.
• units (Optional[nidaqmx.constants.PressureUnits]) – Specifies in
which unit to return pressure measurements from the channel.
• bridge_config
(Optional[nidaqmx.constants.
BridgeConfiguration]) – Specifies information about the bridge configuration and
measurement.
• voltage_excit_source
(Optional[nidaqmx.constants.
ExcitationSource]) – Specifies information about the bridge configuration
and measurement.

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• voltage_excit_val (Optional[float]) – Specifies information about the
bridge configuration and measurement.
• nominal_bridge_resistance (Optional[float]) – Specifies information
about the bridge configuration and measurement.
• forward_coeffs (Optional[List[float]]) – Specifies how to scale electrical
values from the sensor to physical units.
• reverse_coeffs (Optional[List[float]]) – Specifies how to scale electrical
values from the sensor to physical units.
• electrical_units
(Optional[nidaqmx.constants.
BridgeElectricalUnits]) – Specifies how to scale electrical values from
the sensor to physical units.
• physical_units
(Optional[nidaqmx.constants.
BridgePhysicalUnits]) – Specifies how to scale electrical values from the
sensor to physical units.
• custom_scale_name (Optional[str]) – Specifies the name of a custom scale for
the channel. If you want the channel to use a custom scale, specify the name of the custom
scale to this input and set units to FROM_CUSTOM_SCALE.
Returns Indicates the newly created channel object.
Return type nidaqmx._task_modules.channels.ai_channel.AIChannel
add_ai_pressure_bridge_table_chan(physical_channel, name_to_assign_to_channel=u’‘,
min_val=-100.0,
max_val=100.0,
units=, bridge_config=, voltage_excit_source=,
voltage_excit_val=2.5,
nominal_bridge_resistance=350.0,
electrical_vals=None,
electrical_units=,
physical_vals=None,
physical_units=, custom_scale_name=u’‘)
Creates channel(s) that use a Wheatstone bridge to measure pressure. Use this instance with sensors whose
specifications provide a table of electrical values and the corresponding physical values. When you use
this scaling type, NI-DAQmx performs linear scaling between each pair of electrical and physical values.
The input limits specified with min_val and max_val must fall within the smallest and largest physical
values. For any data outside those endpoints, NI-DAQmx coerces that data to the endpoints.
Parameters
• physical_channel (str) – Specifies the names of the physical channels to use to
create virtual channels. The DAQmx physical channel constant lists all physical channels
on devices and modules installed in the system.
• name_to_assign_to_channel (Optional[str]) – Specifies a name to assign
to the virtual channel this function creates. If you do not specify a value for this input,
NI-DAQmx uses the physical channel name as the virtual channel name.
• min_val (Optional[float]) – Specifies in units the minimum value you expect to
measure.
• max_val (Optional[float]) – Specifies in units the maximum value you expect to
measure.

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• units (Optional[nidaqmx.constants.PressureUnits]) – Specifies in
which unit to return pressure measurements from the channel.
• bridge_config
(Optional[nidaqmx.constants.
BridgeConfiguration]) – Specifies information about the bridge configuration and
measurement.
• voltage_excit_source
(Optional[nidaqmx.constants.
ExcitationSource]) – Specifies information about the bridge configuration
and measurement.
• voltage_excit_val (Optional[float]) – Specifies information about the
bridge configuration and measurement.
• nominal_bridge_resistance (Optional[float]) – Specifies information
about the bridge configuration and measurement.
• electrical_vals (Optional[List[float]]) – Specifies how to scale electrical values from the sensor to physical units.
• electrical_units
(Optional[nidaqmx.constants.
BridgeElectricalUnits]) – Specifies how to scale electrical values from
the sensor to physical units.
• physical_vals (Optional[List[float]]) – Specifies how to scale electrical
values from the sensor to physical units.
• physical_units
(Optional[nidaqmx.constants.
BridgePhysicalUnits]) – Specifies how to scale electrical values from the
sensor to physical units.
• custom_scale_name (Optional[str]) – Specifies the name of a custom scale for
the channel. If you want the channel to use a custom scale, specify the name of the custom
scale to this input and set units to FROM_CUSTOM_SCALE.
Returns Indicates the newly created channel object.
Return type nidaqmx._task_modules.channels.ai_channel.AIChannel
add_ai_pressure_bridge_two_point_lin_chan(physical_channel,
name_to_assign_to_channel=u’‘,
min_val=-100.0,
max_val=100.0,
units=, bridge_config=,
voltage_excit_source=,
voltage_excit_val=2.5,
nominal_bridge_resistance=350.0,
first_electrical_val=0.0,
second_electrical_val=2.0,
electrical_units=,
first_physical_val=0.0,
second_physical_val=100.0,
physical_units=, custom_scale_name=u’‘)
Creates channel(s) that use a Wheatstone bridge to measure pressure. Use this instance with sensors whose
specifications do not provide a polynomial for scaling or a table of electrical and physical values. When
you use this scaling type, NI-DAQmx uses two points of electrical and physical values to calculate the slope
and y-intercept of a linear equation and uses that equation to scale electrical values to physical values.
Parameters
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• physical_channel (str) – Specifies the names of the physical channels to use to
create virtual channels. The DAQmx physical channel constant lists all physical channels
on devices and modules installed in the system.
• name_to_assign_to_channel (Optional[str]) – Specifies a name to assign
to the virtual channel this function creates. If you do not specify a value for this input,
NI-DAQmx uses the physical channel name as the virtual channel name.
• min_val (Optional[float]) – Specifies in units the minimum value you expect to
measure.
• max_val (Optional[float]) – Specifies in units the maximum value you expect to
measure.
• units (Optional[nidaqmx.constants.PressureUnits]) – Specifies in
which unit to return pressure measurements from the channel.
• bridge_config
(Optional[nidaqmx.constants.
BridgeConfiguration]) – Specifies information about the bridge configuration and
measurement.
• voltage_excit_source
(Optional[nidaqmx.constants.
ExcitationSource]) – Specifies information about the bridge configuration
and measurement.
• voltage_excit_val (Optional[float]) – Specifies information about the
bridge configuration and measurement.
• nominal_bridge_resistance (Optional[float]) – Specifies information
about the bridge configuration and measurement.
• first_electrical_val (Optional[float]) – Specifies how to scale electrical
values from the sensor to physical units.
• second_electrical_val (Optional[float]) – Specifies how to scale electrical values from the sensor to physical units.
• electrical_units
(Optional[nidaqmx.constants.
BridgeElectricalUnits]) – Specifies how to scale electrical values from
the sensor to physical units.
• first_physical_val (Optional[float]) – Specifies how to scale electrical values from the sensor to physical units.
• second_physical_val (Optional[float]) – Specifies how to scale electrical
values from the sensor to physical units.
• physical_units
(Optional[nidaqmx.constants.
BridgePhysicalUnits]) – Specifies how to scale electrical values from the
sensor to physical units.
• custom_scale_name (Optional[str]) – Specifies the name of a custom scale for
the channel. If you want the channel to use a custom scale, specify the name of the custom
scale to this input and set units to FROM_CUSTOM_SCALE.
Returns Indicates the newly created channel object.
Return type nidaqmx._task_modules.channels.ai_channel.AIChannel

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add_ai_resistance_chan(physical_channel, name_to_assign_to_channel=u’‘, min_val=100.0,
max_val=1000.0, units=, resistance_config=, current_excit_source=,
current_excit_val=0.001, custom_scale_name=u’‘)
Creates channel(s) to measure resistance.
Parameters
• physical_channel (str) – Specifies the names of the physical channels to use to
create virtual channels. The DAQmx physical channel constant lists all physical channels
on devices and modules installed in the system.
• name_to_assign_to_channel (Optional[str]) – Specifies a name to assign
to the virtual channel this function creates. If you do not specify a value for this input,
NI-DAQmx uses the physical channel name as the virtual channel name.
• min_val (Optional[float]) – Specifies in units the minimum value you expect to
measure.
• max_val (Optional[float]) – Specifies in units the maximum value you expect to
measure.
• units (Optional[nidaqmx.constants.ResistanceUnits]) – Specifies the
units to use to return resistance measurements.
• resistance_config
(Optional[nidaqmx.constants.
ResistanceConfiguration]) – Specifies the number of wires to use for
resistive measurements.
• current_excit_source
(Optional[nidaqmx.constants.
ExcitationSource]) – Specifies the source of excitation.
• current_excit_val (Optional[float]) – Specifies in amperes the amount of
excitation to supply to the sensor. Refer to the sensor documentation to determine this
value.
• custom_scale_name (Optional[str]) – Specifies the name of a custom scale for
the channel. If you want the channel to use a custom scale, specify the name of the custom
scale to this input and set units to FROM_CUSTOM_SCALE.
Returns Indicates the newly created channel object.
Return type nidaqmx._task_modules.channels.ai_channel.AIChannel
add_ai_rosette_strain_gage_chan(physical_channel,
rosette_type,
gage_orientation,
rosette_meas_types,
name_to_assign_to_channel=u’‘,
min_val=-0.001,
max_val=0.001,
strain_config=, voltage_excit_source=,
voltage_excit_val=2.5,
gage_factor=2.0,
nominal_gage_resistance=350.0,
poisson_ratio=0.3,
lead_wire_resistance=0.0)
Creates channels to measure two-dimensional strain using a rosette strain gage.
Parameters
• physical_channel (str) – Specifies the names of the physical channels to use to
create the strain gage virtual channels necessary to calculate the rosette measurements
channels.

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• rosette_type (nidaqmx.constants.StrainGageRosetteType) – Specifies information about the rosette configuration and measurements.
• gage_orientation (float) – Specifies information about the rosette configuration
and measurements.
• rosette_meas_types (List[int]) – Specifies information about the rosette configuration and measurements.
• name_to_assign_to_channel (Optional[str]) – Specifies a name to assign
to the virtual channel this function creates. If you do not specify a value for this input,
NI-DAQmx creates a default channel name.
• min_val (Optional[float]) – Specifies the minimum strain you expect to measure.
This value applies to each strain gage in the rosette.
• max_val (Optional[float]) – Specifies the maximum strain you expect to measure.
This value applies to each strain gage in the rosette.
• strain_config
(Optional[nidaqmx.constants.
StrainGageBridgeType]) – Specifies information about the bridge configuration
and measurement.
• voltage_excit_source
(Optional[nidaqmx.constants.
ExcitationSource]) – Specifies information about the bridge configuration
and measurement.
• voltage_excit_val (Optional[float]) – Specifies information about the
bridge configuration and measurement.
• gage_factor (Optional[float]) – Contains information about the strain gage and
measurement.
• nominal_gage_resistance (Optional[float]) – Contains information about
the strain gage and measurement.
• poisson_ratio (Optional[float]) – Contains information about the strain gage
and measurement.
• lead_wire_resistance (Optional[float]) – Specifies information about the
bridge configuration and measurement.
Returns Indicates the newly created channel object.
Return type nidaqmx._task_modules.channels.ai_channel.AIChannel
add_ai_rtd_chan(physical_channel,
name_to_assign_to_channel=u’‘,
min_val=0.0,
max_val=100.0,
units=,
rtd_type=,
resistance_config=,
current_excit_source=,
current_excit_val=0.0025, r_0=100.0)
Creates channel(s) that use an RTD to measure temperature.
Parameters
• physical_channel (str) – Specifies the names of the physical channels to use to
create virtual channels. The DAQmx physical channel constant lists all physical channels
on devices and modules installed in the system.
• name_to_assign_to_channel (Optional[str]) – Specifies a name to assign
to the virtual channel this function creates. If you do not specify a value for this input,
NI-DAQmx uses the physical channel name as the virtual channel name.

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• min_val (Optional[float]) – Specifies in units the minimum value you expect to
measure.
• max_val (Optional[float]) – Specifies in units the maximum value you expect to
measure.
• units (Optional[nidaqmx.constants.TemperatureUnits]) – Specifies
the units to use to return temperature measurements.
• rtd_type (Optional[nidaqmx.constants.RTDType]) – Specifies the type of
RTD connected to the channel.
• resistance_config
(Optional[nidaqmx.constants.
ResistanceConfiguration]) – Specifies the number of wires to use for
resistive measurements.
• current_excit_source
(Optional[nidaqmx.constants.
ExcitationSource]) – Specifies the source of excitation.
• current_excit_val (Optional[float]) – Specifies in amperes the amount of
excitation to supply to the sensor. Refer to the sensor documentation to determine this
value.
• r_0 (Optional[float]) – Is the sensor resistance in ohms at 0 degrees Celsius. The
Callendar-Van Dusen equation requires this value. Refer to the sensor documentation to
determine this value.
Returns Indicates the newly created channel object.
Return type nidaqmx._task_modules.channels.ai_channel.AIChannel
add_ai_strain_gage_chan(physical_channel, name_to_assign_to_channel=u’‘, min_val=0.001, max_val=0.001, units=,
strain_config=,
voltage_excit_source=,
voltage_excit_val=2.5,
gage_factor=2.0,
initial_bridge_voltage=0.0, nominal_gage_resistance=350.0, poisson_ratio=0.3, lead_wire_resistance=0.0, custom_scale_name=u’‘)
Creates channel(s) to measure strain.
Parameters
• physical_channel (str) – Specifies the names of the physical channels to use to
create virtual channels. The DAQmx physical channel constant lists all physical channels
on devices and modules installed in the system.
• name_to_assign_to_channel (Optional[str]) – Specifies a name to assign
to the virtual channel this function creates. If you do not specify a value for this input,
NI-DAQmx uses the physical channel name as the virtual channel name.
• min_val (Optional[float]) – Specifies in units the minimum value you expect to
measure.
• max_val (Optional[float]) – Specifies in units the maximum value you expect to
measure.
• units (Optional[nidaqmx.constants.StrainUnits]) – Specifies the units
to use to return strain measurements.
• strain_config
(Optional[nidaqmx.constants.
StrainGageBridgeType]) – Specifies information about the bridge configuration
and measurement.

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• voltage_excit_source
(Optional[nidaqmx.constants.
ExcitationSource]) – Specifies information about the bridge configuration
and measurement.
• voltage_excit_val (Optional[float]) – Specifies information about the
bridge configuration and measurement.
• gage_factor (Optional[float]) – Contains information about the strain gage and
measurement.
• initial_bridge_voltage (Optional[float]) – Specifies information about
the bridge configuration and measurement.
• nominal_gage_resistance (Optional[float]) – Contains information about
the strain gage and measurement.
• poisson_ratio (Optional[float]) – Contains information about the strain gage
and measurement.
• lead_wire_resistance (Optional[float]) – Specifies information about the
bridge configuration and measurement.
• custom_scale_name (Optional[str]) – Specifies the name of a custom scale for
the channel. If you want the channel to use a custom scale, specify the name of the custom
scale to this input and set units to FROM_CUSTOM_SCALE.
Returns Indicates the newly created channel object.
Return type nidaqmx._task_modules.channels.ai_channel.AIChannel
add_ai_temp_built_in_sensor_chan(physical_channel,
name_to_assign_to_channel=u’‘,
units=)
Creates channel(s) that use the built-in sensor of a terminal block or device to measure temperature. On
SCXI modules, for example, the built-in sensor could be the CJC sensor.
Parameters
• physical_channel (str) – Specifies the names of the physical channels to use to
create virtual channels. The DAQmx physical channel constant lists all physical channels
on devices and modules installed in the system.
• name_to_assign_to_channel (Optional[str]) – Specifies a name to assign
to the virtual channel this function creates. If you do not specify a value for this input,
NI-DAQmx uses the physical channel name as the virtual channel name.
• units (Optional[nidaqmx.constants.TemperatureUnits]) – Specifies
the units to use to return temperature measurements.
Returns Indicates the newly created channel object.
Return type nidaqmx._task_modules.channels.ai_channel.AIChannel
add_ai_thrmcpl_chan(physical_channel,
name_to_assign_to_channel=u’‘,
min_val=0.0,
max_val=100.0,
units=,
thermocouple_type=,
cjc_source=,
cjc_val=25.0, cjc_channel=u’‘)
Creates channel(s) that use a thermocouple to measure temperature.
Parameters
• physical_channel (str) – Specifies the names of the physical channels to use to
create virtual channels. The DAQmx physical channel constant lists all physical channels
on devices and modules installed in the system.
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• name_to_assign_to_channel (Optional[str]) – Specifies a name to assign
to the virtual channel this function creates. If you do not specify a value for this input,
NI-DAQmx uses the physical channel name as the virtual channel name.
• min_val (Optional[float]) – Specifies in units the minimum value you expect to
measure.
• max_val (Optional[float]) – Specifies in units the maximum value you expect to
measure.
• units (Optional[nidaqmx.constants.TemperatureUnits]) – Specifies
the units to use to return temperature measurements.
• thermocouple_type
(Optional[nidaqmx.constants.
ThermocoupleType]) – Specifies the type of thermocouple connected to the
channel. Thermocouple types differ in composition and measurement range.
• cjc_source (Optional[nidaqmx.constants.CJCSource]) – Specifies the
source of cold-junction compensation.
• cjc_val (Optional[float]) – Specifies in units the temperature of the cold junction if you set cjc_source to CONSTANT_VALUE.
• cjc_channel (Optional[str]) – Specifies the channel that acquires the temperature of the thermocouple cold- junction if you set cjc_source to CHANNEL.
Returns Indicates the newly created channel object.
Return type nidaqmx._task_modules.channels.ai_channel.AIChannel
add_ai_thrmstr_chan_iex(physical_channel, name_to_assign_to_channel=u’‘, min_val=0.0,
max_val=100.0, units=, resistance_config=,
current_excit_source=,
current_excit_val=0.00015, a=0.001295361, b=0.0002343159,
c=1.018703e-07)
Creates channel(s) that use a thermistor to measure temperature. Use this instance when the thermistor
requires current excitation.
Parameters
• physical_channel (str) – Specifies the names of the physical channels to use to
create virtual channels. The DAQmx physical channel constant lists all physical channels
on devices and modules installed in the system.
• name_to_assign_to_channel (Optional[str]) – Specifies a name to assign
to the virtual channel this function creates. If you do not specify a value for this input,
NI-DAQmx uses the physical channel name as the virtual channel name.
• min_val (Optional[float]) – Specifies in units the minimum value you expect to
measure.
• max_val (Optional[float]) – Specifies in units the maximum value you expect to
measure.
• units (Optional[nidaqmx.constants.TemperatureUnits]) – Specifies
the units to use to return temperature measurements.
• resistance_config
(Optional[nidaqmx.constants.
ResistanceConfiguration]) – Specifies the number of wires to use for
resistive measurements.

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• current_excit_source
(Optional[nidaqmx.constants.
ExcitationSource]) – Specifies the source of excitation.
• current_excit_val (Optional[float]) – Specifies in amperes the amount of
excitation to supply to the sensor. Refer to the sensor documentation to determine this
value.
• a (Optional[float]) – Contains the constants for the Steinhart-Hart thermistor equation. Refer to the sensor documentation to determine values for these constants.
• b (Optional[float]) – Contains the constants for the Steinhart-Hart thermistor equation. Refer to the sensor documentation to determine values for these constants.
• c (Optional[float]) – Contains the constants for the Steinhart-Hart thermistor equation. Refer to the sensor documentation to determine values for these constants.
Returns Indicates the newly created channel object.
Return type nidaqmx._task_modules.channels.ai_channel.AIChannel
add_ai_thrmstr_chan_vex(physical_channel, name_to_assign_to_channel=u’‘, min_val=0.0,
max_val=100.0, units=, resistance_config=,
voltage_excit_source=, voltage_excit_val=2.5, a=0.001295361, b=0.0002343159, c=1.018703e07, r_1=5000.0)
Creates channel(s) that use a thermistor to measure temperature. Use this instance when the thermistor
requires voltage excitation.
Parameters
• physical_channel (str) – Specifies the names of the physical channels to use to
create virtual channels. The DAQmx physical channel constant lists all physical channels
on devices and modules installed in the system.
• name_to_assign_to_channel (Optional[str]) – Specifies a name to assign
to the virtual channel this function creates. If you do not specify a value for this input,
NI-DAQmx uses the physical channel name as the virtual channel name.
• min_val (Optional[float]) – Specifies in units the minimum value you expect to
measure.
• max_val (Optional[float]) – Specifies in units the maximum value you expect to
measure.
• units (Optional[nidaqmx.constants.TemperatureUnits]) – Specifies
the units to use to return temperature measurements.
• resistance_config
(Optional[nidaqmx.constants.
ResistanceConfiguration]) – Specifies the number of wires to use for
resistive measurements.
• voltage_excit_source
(Optional[nidaqmx.constants.
ExcitationSource]) – Specifies the source of excitation.
• voltage_excit_val (Optional[float]) – Specifies in volts the amount of excitation supplied to the sensor. Refer to the sensor documentation to determine appropriate
excitation values.
• a (Optional[float]) – Contains the constants for the Steinhart-Hart thermistor equation. Refer to the sensor documentation to determine values for these constants.

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• b (Optional[float]) – Contains the constants for the Steinhart-Hart thermistor equation. Refer to the sensor documentation to determine values for these constants.
• c (Optional[float]) – Contains the constants for the Steinhart-Hart thermistor equation. Refer to the sensor documentation to determine values for these constants.
• r_1 (Optional[float]) – Specifies in ohms the value of the reference resistor.
Returns Indicates the newly created channel object.
Return type nidaqmx._task_modules.channels.ai_channel.AIChannel
add_ai_torque_bridge_polynomial_chan(physical_channel,
name_to_assign_to_channel=u’‘,
min_val=-100.0,
max_val=100.0,
units=,
bridge_config=, voltage_excit_source=,
voltage_excit_val=2.5,
nominal_bridge_resistance=350.0,
forward_coeffs=None, reverse_coeffs=None, electrical_units=, physical_units=, custom_scale_name=u’‘)
Creates channel(s) that use a Wheatstone bridge to measure torque. Use this instance with sensors whose
specifications provide a polynomial to convert electrical values to physical values. When you use this
scaling type, NI-DAQmx requires coefficients for a polynomial that converts electrical values to physical
values (forward), as well as coefficients for a polynomial that converts physical values to electrical values (reverse). If you only know one set of coefficients, use the DAQmx Compute Reverse Polynomial
Coefficients function to generate the other set.
Parameters
• physical_channel (str) – Specifies the names of the physical channels to use to
create virtual channels. The DAQmx physical channel constant lists all physical channels
on devices and modules installed in the system.
• name_to_assign_to_channel (Optional[str]) – Specifies a name to assign
to the virtual channel this function creates. If you do not specify a value for this input,
NI-DAQmx uses the physical channel name as the virtual channel name.
• min_val (Optional[float]) – Specifies in units the minimum value you expect to
measure.
• max_val (Optional[float]) – Specifies in units the maximum value you expect to
measure.
• units (Optional[nidaqmx.constants.TorqueUnits]) – Specifies in which
unit to return torque measurements from the channel.
• bridge_config
(Optional[nidaqmx.constants.
BridgeConfiguration]) – Specifies information about the bridge configuration and
measurement.
• voltage_excit_source
(Optional[nidaqmx.constants.
ExcitationSource]) – Specifies information about the bridge configuration
and measurement.
• voltage_excit_val (Optional[float]) – Specifies information about the
bridge configuration and measurement.

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• nominal_bridge_resistance (Optional[float]) – Specifies information
about the bridge configuration and measurement.
• forward_coeffs (Optional[List[float]]) – Specifies how to scale electrical
values from the sensor to physical units.
• reverse_coeffs (Optional[List[float]]) – Specifies how to scale electrical
values from the sensor to physical units.
• electrical_units
(Optional[nidaqmx.constants.
BridgeElectricalUnits]) – Specifies how to scale electrical values from
the sensor to physical units.
• physical_units
(Optional[nidaqmx.constants.
BridgePhysicalUnits]) – Specifies how to scale electrical values from the
sensor to physical units.
• custom_scale_name (Optional[str]) – Specifies the name of a custom scale for
the channel. If you want the channel to use a custom scale, specify the name of the custom
scale to this input and set units to FROM_CUSTOM_SCALE.
Returns Indicates the newly created channel object.
Return type nidaqmx._task_modules.channels.ai_channel.AIChannel
add_ai_torque_bridge_table_chan(physical_channel,
name_to_assign_to_channel=u’‘,
min_val=-100.0,
max_val=100.0,
units=,
bridge_config=, voltage_excit_source=,
voltage_excit_val=2.5,
nominal_bridge_resistance=350.0,
electrical_vals=None,
electrical_units=,
physical_vals=None,
physical_units=, custom_scale_name=u’‘)
Creates channel(s) that use a Wheatstone bridge to measure torque. Use this instance with sensors whose
specifications provide a table of electrical values and the corresponding physical values. When you use
this scaling type, NI-DAQmx performs linear scaling between each pair of electrical and physical values.
The input limits specified with min_val and max_val must fall within the smallest and largest physical
values. For any data outside those endpoints, NI-DAQmx coerces that data to the endpoints.
Parameters
• physical_channel (str) – Specifies the names of the physical channels to use to
create virtual channels. The DAQmx physical channel constant lists all physical channels
on devices and modules installed in the system.
• name_to_assign_to_channel (Optional[str]) – Specifies a name to assign
to the virtual channel this function creates. If you do not specify a value for this input,
NI-DAQmx uses the physical channel name as the virtual channel name.
• min_val (Optional[float]) – Specifies in units the minimum value you expect to
measure.
• max_val (Optional[float]) – Specifies in units the maximum value you expect to
measure.
• units (Optional[nidaqmx.constants.TorqueUnits]) – Specifies in which
unit to return torque measurements from the channel.

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• bridge_config
(Optional[nidaqmx.constants.
BridgeConfiguration]) – Specifies information about the bridge configuration and
measurement.
• voltage_excit_source
(Optional[nidaqmx.constants.
ExcitationSource]) – Specifies information about the bridge configuration
and measurement.
• voltage_excit_val (Optional[float]) – Specifies information about the
bridge configuration and measurement.
• nominal_bridge_resistance (Optional[float]) – Specifies information
about the bridge configuration and measurement.
• electrical_vals (Optional[List[float]]) – Specifies how to scale electrical values from the sensor to physical units.
• electrical_units
(Optional[nidaqmx.constants.
BridgeElectricalUnits]) – Specifies how to scale electrical values from
the sensor to physical units.
• physical_vals (Optional[List[float]]) – Specifies how to scale electrical
values from the sensor to physical units.
• physical_units
(Optional[nidaqmx.constants.
BridgePhysicalUnits]) – Specifies how to scale electrical values from the
sensor to physical units.
• custom_scale_name (Optional[str]) – Specifies the name of a custom scale for
the channel. If you want the channel to use a custom scale, specify the name of the custom
scale to this input and set units to FROM_CUSTOM_SCALE.
Returns Indicates the newly created channel object.
Return type nidaqmx._task_modules.channels.ai_channel.AIChannel
add_ai_torque_bridge_two_point_lin_chan(physical_channel,
name_to_assign_to_channel=u’‘,
min_val=-100.0,
max_val=100.0,
units=, bridge_config=,
voltage_excit_source=,
voltage_excit_val=2.5,
nominal_bridge_resistance=350.0,
first_electrical_val=0.0,
second_electrical_val=2.0,
electrical_units=,
first_physical_val=0.0,
second_physical_val=100.0,
physical_units=, custom_scale_name=u’‘)
Creates channel(s) that use a Wheatstone bridge to measure torque. Use this instance with sensors whose
specifications do not provide a polynomial for scaling or a table of electrical and physical values. When
you use this scaling type, NI-DAQmx uses two points of electrical and physical values to calculate the slope
and y-intercept of a linear equation and uses that equation to scale electrical values to physical values.
Parameters
• physical_channel (str) – Specifies the names of the physical channels to use to
create virtual channels. The DAQmx physical channel constant lists all physical channels
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on devices and modules installed in the system.
• name_to_assign_to_channel (Optional[str]) – Specifies a name to assign
to the virtual channel this function creates. If you do not specify a value for this input,
NI-DAQmx uses the physical channel name as the virtual channel name.
• min_val (Optional[float]) – Specifies in units the minimum value you expect to
measure.
• max_val (Optional[float]) – Specifies in units the maximum value you expect to
measure.
• units (Optional[nidaqmx.constants.TorqueUnits]) – Specifies in which
unit to return torque measurements from the channel.
• bridge_config
(Optional[nidaqmx.constants.
BridgeConfiguration]) – Specifies information about the bridge configuration and
measurement.
• voltage_excit_source
(Optional[nidaqmx.constants.
ExcitationSource]) – Specifies information about the bridge configuration
and measurement.
• voltage_excit_val (Optional[float]) – Specifies information about the
bridge configuration and measurement.
• nominal_bridge_resistance (Optional[float]) – Specifies information
about the bridge configuration and measurement.
• first_electrical_val (Optional[float]) – Specifies how to scale electrical
values from the sensor to physical units.
• second_electrical_val (Optional[float]) – Specifies how to scale electrical values from the sensor to physical units.
• electrical_units
(Optional[nidaqmx.constants.
BridgeElectricalUnits]) – Specifies how to scale electrical values from
the sensor to physical units.
• first_physical_val (Optional[float]) – Specifies how to scale electrical values from the sensor to physical units.
• second_physical_val (Optional[float]) – Specifies how to scale electrical
values from the sensor to physical units.
• physical_units
(Optional[nidaqmx.constants.
BridgePhysicalUnits]) – Specifies how to scale electrical values from the
sensor to physical units.
• custom_scale_name (Optional[str]) – Specifies the name of a custom scale for
the channel. If you want the channel to use a custom scale, specify the name of the custom
scale to this input and set units to FROM_CUSTOM_SCALE.
Returns Indicates the newly created channel object.
Return type nidaqmx._task_modules.channels.ai_channel.AIChannel

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add_ai_velocity_iepe_chan(physical_channel,
name_to_assign_to_channel=u’‘,
terminal_config=,
min_val=-50.0,
max_val=50.0,
units=,
sensitivity=100.0,
sensitivity_units=, current_excit_source=, current_excit_val=0.002, custom_scale_name=u’‘)
Creates channel(s) that use an IEPE velocity sensor to measure velocity.
Parameters
• physical_channel (str) – Specifies the names of the physical channels to use to
create virtual channels. The DAQmx physical channel constant lists all physical channels
on devices and modules installed in the system.
• name_to_assign_to_channel (Optional[str]) – Specifies a name to assign
to the virtual channel this function creates. If you do not specify a value for this input,
NI-DAQmx uses the physical channel name as the virtual channel name.
• terminal_config
(Optional[nidaqmx.constants.
TerminalConfiguration]) – Specifies the input terminal configuration for
the channel.
• min_val (Optional[float]) – Specifies in units the minimum value you expect to
measure.
• max_val (Optional[float]) – Specifies in units the maximum value you expect to
measure.
• units (Optional[nidaqmx.constants.VelocityUnits]) – Specifies in
which unit to return velocity measurements from the channel.
• sensitivity (Optional[float]) – Is the sensitivity of the sensor. This value is in
the units you specify with the sensitivity_units input. Refer to the sensor documentation
to determine this value.
• sensitivity_units
(Optional[nidaqmx.constants.
VelocityIEPESensorSensitivityUnits]) – Specifies the units of the
sensitivity input.
• current_excit_source
(Optional[nidaqmx.constants.
ExcitationSource]) – Specifies the source of excitation.
• current_excit_val (Optional[float]) – Specifies in amperes the amount of
excitation to supply to the sensor. Refer to the sensor documentation to determine this
value.
• custom_scale_name (Optional[str]) – Specifies the name of a custom scale for
the channel. If you want the channel to use a custom scale, specify the name of the custom
scale to this input and set units to FROM_CUSTOM_SCALE.
Returns Indicates the newly created channel object.
Return type nidaqmx._task_modules.channels.ai_channel.AIChannel
add_ai_voltage_chan(physical_channel,
name_to_assign_to_channel=u’‘,
terminal_config=,
min_val=5.0,
max_val=5.0,
units=,
custom_scale_name=u’‘)
Creates channel(s) to measure voltage. If the measurement requires the use of internal excitation or you
need excitation to scale the voltage, use the AI Custom Voltage with Excitation instance of this function.
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Parameters
• physical_channel (str) – Specifies the names of the physical channels to use to
create virtual channels. The DAQmx physical channel constant lists all physical channels
on devices and modules installed in the system.
• name_to_assign_to_channel (Optional[str]) – Specifies a name to assign
to the virtual channel this function creates. If you do not specify a value for this input,
NI-DAQmx uses the physical channel name as the virtual channel name.
• terminal_config
(Optional[nidaqmx.constants.
TerminalConfiguration]) – Specifies the input terminal configuration for
the channel.
• min_val (Optional[float]) – Specifies in units the minimum value you expect to
measure.
• max_val (Optional[float]) – Specifies in units the maximum value you expect to
measure.
• units (Optional[nidaqmx.constants.VoltageUnits]) – Specifies the
units to use to return voltage measurements.
• custom_scale_name (Optional[str]) – Specifies the name of a custom scale for
the channel. If you want the channel to use a custom scale, specify the name of the custom
scale to this input and set units to FROM_CUSTOM_SCALE.
Returns Indicates the newly created channel object.
Return type nidaqmx._task_modules.channels.ai_channel.AIChannel
add_ai_voltage_chan_with_excit(physical_channel,
name_to_assign_to_channel=u’‘,
terminal_config=,
min_val=-10.0,
max_val=10.0,
units=,
bridge_config=, voltage_excit_source=,
voltage_excit_val=0.0,
use_excit_for_scaling=False, custom_scale_name=u’‘)
Creates channel(s) to measure voltage. Use this instance for custom sensors that require excitation. You
can use the excitation to scale the measurement.
Parameters
• physical_channel (str) – Specifies the names of the physical channels to use to
create virtual channels. The DAQmx physical channel constant lists all physical channels
on devices and modules installed in the system.
• name_to_assign_to_channel (Optional[str]) – Specifies a name to assign
to the virtual channel this function creates. If you do not specify a value for this input,
NI-DAQmx uses the physical channel name as the virtual channel name.
• terminal_config
(Optional[nidaqmx.constants.
TerminalConfiguration]) – Specifies the input terminal configuration for
the channel.
• min_val (Optional[float]) – Specifies in units the minimum value you expect to
measure.
• max_val (Optional[float]) – Specifies in units the maximum value you expect to
measure.

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• units (Optional[nidaqmx.constants.VoltageUnits]) – Specifies the
units to use to return voltage measurements.
• bridge_config
(Optional[nidaqmx.constants.
BridgeConfiguration]) – Specifies what type of Wheatstone bridge the sensor
is.
• voltage_excit_source
(Optional[nidaqmx.constants.
ExcitationSource]) – Specifies the source of excitation.
• voltage_excit_val (Optional[float]) – Specifies in volts the amount of excitation supplied to the sensor. Refer to the sensor documentation to determine appropriate
excitation values.
• use_excit_for_scaling (Optional[bool]) – Specifies if NI- DAQmx divides
the measurement by the excitation. You should typically set use_excit_for_scaling to
True for ratiometric transducers. If you set use_excit_for_scaling to True, set max_val
and min_val to reflect the scaling.
• custom_scale_name (Optional[str]) – Specifies the name of a custom scale for
the channel. If you want the channel to use a custom scale, specify the name of the custom
scale to this input and set units to FROM_CUSTOM_SCALE.
Returns Indicates the newly created channel object.
Return type nidaqmx._task_modules.channels.ai_channel.AIChannel
add_ai_voltage_rms_chan(physical_channel,
name_to_assign_to_channel=u’‘,
terminal_config=, min_val=5.0, max_val=5.0, units=, custom_scale_name=u’‘)
Creates channel(s) to measure voltage RMS, the average (mean) power of the acquired voltage.
Parameters
• physical_channel (str) – Specifies the names of the physical channels to use to
create virtual channels. The DAQmx physical channel constant lists all physical channels
on devices and modules installed in the system.
• name_to_assign_to_channel (Optional[str]) – Specifies a name to assign
to the virtual channel this function creates. If you do not specify a value for this input,
NI-DAQmx uses the physical channel name as the virtual channel name.
• terminal_config
(Optional[nidaqmx.constants.
TerminalConfiguration]) – Specifies the input terminal configuration for
the channel.
• min_val (Optional[float]) – Specifies in units the minimum value you expect to
measure.
• max_val (Optional[float]) – Specifies in units the maximum value you expect to
measure.
• units (Optional[nidaqmx.constants.VoltageUnits]) – Specifies the
units to use to return voltage measurements.
• custom_scale_name (Optional[str]) – Specifies the name of a custom scale for
the channel. If you want the channel to use a custom scale, specify the name of the custom
scale to this input and set units to FROM_CUSTOM_SCALE.
Returns Indicates the newly created channel object.
Return type nidaqmx._task_modules.channels.ai_channel.AIChannel

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add_teds_ai_accel_chan(physical_channel,
name_to_assign_to_channel=u’‘,
terminal_config=,
min_val=5.0,
max_val=5.0,
units=,
current_excit_source=,
current_excit_val=0.004, custom_scale_name=u’‘)
Creates channel(s) that use an accelerometer to measure acceleration. You must configure the physical
channel(s) with TEDS information to use this function.
Parameters
• physical_channel (str) – Specifies the names of the physical channels to use to
create virtual channels. The DAQmx physical channel constant lists all physical channels
on devices and modules installed in the system.
• name_to_assign_to_channel (Optional[str]) – Specifies a name to assign
to the virtual channel this function creates. If you do not specify a value for this input,
NI-DAQmx uses the physical channel name as the virtual channel name.
• terminal_config
(Optional[nidaqmx.constants.
TerminalConfiguration]) – Specifies the input terminal configuration for
the channel.
• min_val (Optional[float]) – Specifies in units the minimum value you expect to
measure.
• max_val (Optional[float]) – Specifies in units the maximum value you expect to
measure.
• units (Optional[nidaqmx.constants.AccelUnits]) – Specifies the units to
use to return acceleration measurements from the channel.
• current_excit_source
(Optional[nidaqmx.constants.
ExcitationSource]) – Specifies the source of excitation.
• current_excit_val (Optional[float]) – Specifies in amperes the amount of
excitation to supply to the sensor. Refer to the sensor documentation to determine this
value.
• custom_scale_name (Optional[str]) – Specifies the name of a custom scale for
the channel. If you want the channel to use a custom scale, specify the name of the custom
scale to this input and set units to FROM_CUSTOM_SCALE.
Returns Indicates the newly created channel object.
Return type nidaqmx._task_modules.channels.ai_channel.AIChannel
add_teds_ai_bridge_chan(physical_channel, name_to_assign_to_channel=u’‘, min_val=0.002, max_val=0.002, units=,
voltage_excit_source=,
voltage_excit_val=2.5, custom_scale_name=u’‘)
Creates channel(s) that measure a Wheatstone bridge. You must configure the physical channel(s) with
TEDS information to use this function. Use this instance with bridge-based sensors that measure phenomena other than strain, force, pressure, or torque, or that scale data to physical units NI-DAQmx does not
support.
Parameters
• physical_channel (str) – Specifies the names of the physical channels to use to
create virtual channels. The DAQmx physical channel constant lists all physical channels
on devices and modules installed in the system.

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• name_to_assign_to_channel (Optional[str]) – Specifies a name to assign
to the virtual channel this function creates. If you do not specify a value for this input,
NI-DAQmx uses the physical channel name as the virtual channel name.
• min_val (Optional[float]) – Specifies in units the minimum value you expect to
measure.
• max_val (Optional[float]) – Specifies in units the maximum value you expect to
measure.
• units (Optional[nidaqmx.constants.TEDSUnits]) – Specifies in which
unit to return measurements from the channel.
• voltage_excit_source
(Optional[nidaqmx.constants.
ExcitationSource]) – Specifies the source of excitation.
• voltage_excit_val (Optional[float]) – Specifies in volts the amount of excitation supplied to the sensor. Refer to the sensor documentation to determine appropriate
excitation values.
• custom_scale_name (Optional[str]) – Specifies the name of a custom scale for
the channel. If you want the channel to use a custom scale, specify the name of the custom
scale to this input and set units to FROM_CUSTOM_SCALE.
Returns Indicates the newly created channel object.
Return type nidaqmx._task_modules.channels.ai_channel.AIChannel
add_teds_ai_current_chan(physical_channel,
name_to_assign_to_channel=u’‘,
terminal_config=, min_val=0.01, max_val=0.01, units=,
shunt_resistor_loc=, ext_shunt_resistor_val=249.0, custom_scale_name=u’‘)
Creates channel(s) to measure current. You must configure the physical channel(s) with TEDS information
to use this function.
Parameters
• physical_channel (str) – Specifies the names of the physical channels to use to
create virtual channels. The DAQmx physical channel constant lists all physical channels
on devices and modules installed in the system.
• name_to_assign_to_channel (Optional[str]) – Specifies a name to assign
to the virtual channel this function creates. If you do not specify a value for this input,
NI-DAQmx uses the physical channel name as the virtual channel name.
• terminal_config
(Optional[nidaqmx.constants.
TerminalConfiguration]) – Specifies the input terminal configuration for
the channel.
• min_val (Optional[float]) – Specifies in units the minimum value you expect to
measure.
• max_val (Optional[float]) – Specifies in units the maximum value you expect to
measure.
• units (Optional[nidaqmx.constants.TEDSUnits]) – Specifies the units to
use to return measurements.
• shunt_resistor_loc
(Optional[nidaqmx.constants.
CurrentShuntResistorLocation]) – Specifies the location of the shunt
resistor. For devices with built-in shunt resistors, specify the location as INTERNAL.
For devices that do not have built-in shunt resistors, you must attach an external one, set
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this input to EXTERNAL and use the ext_shunt_resistor_val input to specify the value
of the resistor.
• ext_shunt_resistor_val (Optional[float]) – Specifies in ohms the resistance of an external shunt resistor.
• custom_scale_name (Optional[str]) – Specifies the name of a custom scale for
the channel. If you want the channel to use a custom scale, specify the name of the custom
scale to this input and set units to FROM_CUSTOM_SCALE.
Returns Indicates the newly created channel object.
Return type nidaqmx._task_modules.channels.ai_channel.AIChannel
add_teds_ai_force_bridge_chan(physical_channel,
name_to_assign_to_channel=u’‘,
min_val=-100.0,
max_val=100.0,
units=,
voltage_excit_source=,
voltage_excit_val=2.5, custom_scale_name=u’‘)
Creates channel(s) that use a Wheatstone bridge to measure force or load. You must configure the physical
channel(s) with TEDS information to use this function. NI-DAQmx scales electrical values to physical
values according to that TEDS information.
Parameters
• physical_channel (str) – Specifies the names of the physical channels to use to
create virtual channels. The DAQmx physical channel constant lists all physical channels
on devices and modules installed in the system.
• name_to_assign_to_channel (Optional[str]) – Specifies a name to assign
to the virtual channel this function creates. If you do not specify a value for this input,
NI-DAQmx uses the physical channel name as the virtual channel name.
• min_val (Optional[float]) – Specifies in units the minimum value you expect to
measure.
• max_val (Optional[float]) – Specifies in units the maximum value you expect to
measure.
• units (Optional[nidaqmx.constants.ForceUnits]) – Specifies in which
unit to return force measurements from the channel.
• voltage_excit_source
(Optional[nidaqmx.constants.
ExcitationSource]) – Specifies the source of excitation.
• voltage_excit_val (Optional[float]) – Specifies in volts the amount of excitation supplied to the sensor. Refer to the sensor documentation to determine appropriate
excitation values.
• custom_scale_name (Optional[str]) – Specifies the name of a custom scale for
the channel. If you want the channel to use a custom scale, specify the name of the custom
scale to this input and set units to FROM_CUSTOM_SCALE.
Returns Indicates the newly created channel object.
Return type nidaqmx._task_modules.channels.ai_channel.AIChannel
add_teds_ai_force_iepe_chan(physical_channel,
name_to_assign_to_channel=u’‘,
terminal_config=,
min_val=-2000.0,
max_val=2000.0,
units=,
current_excit_source=,
current_excit_val=0.001, custom_scale_name=u’‘)
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Creates channel(s) that use an IEPE force sensor to measure force or load. You must configure the physical
channel(s) with TEDS information to use this function.
Parameters
• physical_channel (str) – Specifies the names of the physical channels to use to
create virtual channels. The DAQmx physical channel constant lists all physical channels
on devices and modules installed in the system.
• name_to_assign_to_channel (Optional[str]) – Specifies a name to assign
to the virtual channel this function creates. If you do not specify a value for this input,
NI-DAQmx uses the physical channel name as the virtual channel name.
• terminal_config
(Optional[nidaqmx.constants.
TerminalConfiguration]) – Specifies the input terminal configuration for
the channel.
• min_val (Optional[float]) – Specifies in units the minimum value you expect to
measure.
• max_val (Optional[float]) – Specifies in units the maximum value you expect to
measure.
• units (Optional[nidaqmx.constants.ForceUnits]) – Specifies in which
unit to return force measurements from the channel.
• current_excit_source
(Optional[nidaqmx.constants.
ExcitationSource]) – Specifies the source of excitation.
• current_excit_val (Optional[float]) – Specifies in amperes the amount of
excitation to supply to the sensor. Refer to the sensor documentation to determine this
value.
• custom_scale_name (Optional[str]) – Specifies the name of a custom scale for
the channel. If you want the channel to use a custom scale, specify the name of the custom
scale to this input and set units to FROM_CUSTOM_SCALE.
Returns Indicates the newly created channel object.
Return type nidaqmx._task_modules.channels.ai_channel.AIChannel
add_teds_ai_microphone_chan(physical_channel,
name_to_assign_to_channel=u’‘,
terminal_config=,
units=,
max_snd_press_level=100.0,
current_excit_source=,
current_excit_val=0.004, custom_scale_name=u’‘)
Creates channel(s) that use a microphone to measure sound pressure. You must configure the physical
channel(s) with TEDS information to use this function.
Parameters
• physical_channel (str) – Specifies the names of the physical channels to use to
create virtual channels. You must use physical channels that you configured with TEDS
information. The DAQmx physical channel constant lists all physical channels on devices
and modules installed in the system.
• name_to_assign_to_channel (Optional[str]) – Specifies a name to assign
to the virtual channel this function creates. If you do not specify a value for this input,
NI-DAQmx uses the physical channel name as the virtual channel name.

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• terminal_config
(Optional[nidaqmx.constants.
TerminalConfiguration]) – Specifies the input terminal configuration for
the channel.
• units (Optional[nidaqmx.constants.SoundPressureUnits]) – Specifies the units to use to return sound pressure measurements.
• max_snd_press_level (Optional[float]) – Is the maximum instantaneous
sound pressure level you expect to measure. This value is in decibels, referenced to 20
micropascals.
• current_excit_source
(Optional[nidaqmx.constants.
ExcitationSource]) – Specifies the source of excitation.
• current_excit_val (Optional[float]) – Specifies in amperes the amount of
excitation to supply to the sensor. Refer to the sensor documentation to determine this
value.
• custom_scale_name (Optional[str]) – Specifies the name of a custom scale for
the channel. If you want the channel to use a custom scale, specify the name of the custom
scale to this input and set units to FROM_CUSTOM_SCALE.
Returns Indicates the newly created channel object.
Return type nidaqmx._task_modules.channels.ai_channel.AIChannel
add_teds_ai_pos_lvdt_chan(physical_channel, name_to_assign_to_channel=u’‘, min_val=0.1, max_val=0.1, units=,
voltage_excit_source=,
voltage_excit_val=1.0,
voltage_excit_freq=2500.0,
ac_excit_wire_mode=,
custom_scale_name=u’‘)
Creates channel(s) that use an LVDT to measure linear position. You must configure the physical channel(s) with TEDS information to use this function.
Parameters
• physical_channel (str) – Specifies the names of the physical channels to use to
create virtual channels. The DAQmx physical channel constant lists all physical channels
on devices and modules installed in the system.
• name_to_assign_to_channel (Optional[str]) – Specifies a name to assign
to the virtual channel this function creates. If you do not specify a value for this input,
NI-DAQmx uses the physical channel name as the virtual channel name.
• min_val (Optional[float]) – Specifies in units the minimum value you expect to
measure.
• max_val (Optional[float]) – Specifies in units the maximum value you expect to
measure.
• units (Optional[nidaqmx.constants.LengthUnits]) – Specifies the units
to use to return linear position measurements from the channel.
• voltage_excit_source
(Optional[nidaqmx.constants.
ExcitationSource]) – Specifies the source of excitation.
• voltage_excit_val (Optional[float]) – Specifies in volts the amount of excitation supplied to the sensor. Refer to the sensor documentation to determine appropriate
excitation values.
• voltage_excit_freq (Optional[float]) – Specifies in hertz the excitation frequency that the sensor requires. Refer to the sensor documentation to determine this value.
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• ac_excit_wire_mode
(Optional[nidaqmx.constants.
ACExcitWireMode]) – Is the number of leads on the sensor. Some sensors
require you to tie leads together to create a four- or five- wire sensor. Refer to the sensor
documentation for more information.
• custom_scale_name (Optional[str]) – Specifies the name of a custom scale for
the channel. If you want the channel to use a custom scale, specify the name of the custom
scale to this input and set units to FROM_CUSTOM_SCALE.
Returns Indicates the newly created channel object.
Return type nidaqmx._task_modules.channels.ai_channel.AIChannel
add_teds_ai_pos_rvdt_chan(physical_channel, name_to_assign_to_channel=u’‘, min_val=70.0,
max_val=70.0,
units=, voltage_excit_source=,
voltage_excit_val=1.0,
voltage_excit_freq=2500.0,
ac_excit_wire_mode=,
custom_scale_name=u’‘)
Creates channel(s) that use an RVDT to measure angular position. You must configure the physical channel(s) with TEDS information to use this function.
Parameters
• physical_channel (str) – Specifies the names of the physical channels to use to
create virtual channels. The DAQmx physical channel constant lists all physical channels
on devices and modules installed in the system.
• name_to_assign_to_channel (Optional[str]) – Specifies a name to assign
to the virtual channel this function creates. If you do not specify a value for this input,
NI-DAQmx uses the physical channel name as the virtual channel name.
• min_val (Optional[float]) – Specifies in units the minimum value you expect to
measure.
• max_val (Optional[float]) – Specifies in units the maximum value you expect to
measure.
• units (Optional[nidaqmx.constants.AngleUnits]) – Specifies the units to
use to return angular position measurements from the channel.
• voltage_excit_source
(Optional[nidaqmx.constants.
ExcitationSource]) – Specifies the source of excitation.
• voltage_excit_val (Optional[float]) – Specifies in volts the amount of excitation supplied to the sensor. Refer to the sensor documentation to determine appropriate
excitation values.
• voltage_excit_freq (Optional[float]) – Specifies in hertz the excitation frequency that the sensor requires. Refer to the sensor documentation to determine this value.
• ac_excit_wire_mode
(Optional[nidaqmx.constants.
ACExcitWireMode]) – Is the number of leads on the sensor. Some sensors
require you to tie leads together to create a four- or five- wire sensor. Refer to the sensor
documentation for more information.
• custom_scale_name (Optional[str]) – Specifies the name of a custom scale for
the channel. If you want the channel to use a custom scale, specify the name of the custom
scale to this input and set units to FROM_CUSTOM_SCALE.
Returns Indicates the newly created channel object.
Return type nidaqmx._task_modules.channels.ai_channel.AIChannel
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add_teds_ai_pressure_bridge_chan(physical_channel,
name_to_assign_to_channel=u’‘,
min_val=-100.0,
max_val=100.0,
units=, voltage_excit_source=,
voltage_excit_val=2.5,
custom_scale_name=u’‘)
Creates channel(s) that use a Wheatstone bridge to measure pressure. You must configure the physical
channel(s) with TEDS information to use this function. NI-DAQmx scales electrical values to physical
values according to that TEDS information.
Parameters
• physical_channel (str) – Specifies the names of the physical channels to use to
create virtual channels. The DAQmx physical channel constant lists all physical channels
on devices and modules installed in the system.
• name_to_assign_to_channel (Optional[str]) – Specifies a name to assign
to the virtual channel this function creates. If you do not specify a value for this input,
NI-DAQmx uses the physical channel name as the virtual channel name.
• min_val (Optional[float]) – Specifies in units the minimum value you expect to
measure.
• max_val (Optional[float]) – Specifies in units the maximum value you expect to
measure.
• units (Optional[nidaqmx.constants.PressureUnits]) – Specifies in
which unit to return pressure measurements from the channel.
• voltage_excit_source
(Optional[nidaqmx.constants.
ExcitationSource]) – Specifies the source of excitation.
• voltage_excit_val (Optional[float]) – Specifies in volts the amount of excitation supplied to the sensor. Refer to the sensor documentation to determine appropriate
excitation values.
• custom_scale_name (Optional[str]) – Specifies the name of a custom scale for
the channel. If you want the channel to use a custom scale, specify the name of the custom
scale to this input and set units to FROM_CUSTOM_SCALE.
Returns Indicates the newly created channel object.
Return type nidaqmx._task_modules.channels.ai_channel.AIChannel
add_teds_ai_resistance_chan(physical_channel,
name_to_assign_to_channel=u’‘,
min_val=100.0,
max_val=1000.0,
units=,
resistance_config=, current_excit_source=,
current_excit_val=0.001, custom_scale_name=u’‘)
Creates channel(s) to measure resistance. You must configure the physical channel(s) with TEDS information to use this function.
Parameters
• physical_channel (str) – Specifies the names of the physical channels to use to
create virtual channels. The DAQmx physical channel constant lists all physical channels
on devices and modules installed in the system.
• name_to_assign_to_channel (Optional[str]) – Specifies a name to assign
to the virtual channel this function creates. If you do not specify a value for this input,
NI-DAQmx uses the physical channel name as the virtual channel name.
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• min_val (Optional[float]) – Specifies in units the minimum value you expect to
measure.
• max_val (Optional[float]) – Specifies in units the maximum value you expect to
measure.
• units (Optional[nidaqmx.constants.TEDSUnits]) – Specifies the units to
use to return measurements.
• resistance_config
(Optional[nidaqmx.constants.
ResistanceConfiguration]) – Specifies the number of wires to use for
resistive measurements.
• current_excit_source
(Optional[nidaqmx.constants.
ExcitationSource]) – Specifies the source of excitation.
• current_excit_val (Optional[float]) – Specifies in amperes the amount of
excitation to supply to the sensor. Refer to the sensor documentation to determine this
value.
• custom_scale_name (Optional[str]) – Specifies the name of a custom scale for
the channel. If you want the channel to use a custom scale, specify the name of the custom
scale to this input and set units to FROM_CUSTOM_SCALE.
Returns Indicates the newly created channel object.
Return type nidaqmx._task_modules.channels.ai_channel.AIChannel
add_teds_ai_rtd_chan(physical_channel,
name_to_assign_to_channel=u’‘,
min_val=0.0,
max_val=100.0,
units=,
resistance_config=,
current_excit_source=,
current_excit_val=0.0025)
Creates channel(s) that use an RTD to measure temperature. You must configure the physical channel(s)
with TEDS information to use this function.
Parameters
• physical_channel (str) – Specifies the names of the physical channels to use to
create virtual channels. The DAQmx physical channel constant lists all physical channels
on devices and modules installed in the system.
• name_to_assign_to_channel (Optional[str]) – Specifies a name to assign
to the virtual channel this function creates. If you do not specify a value for this input,
NI-DAQmx uses the physical channel name as the virtual channel name.
• min_val (Optional[float]) – Specifies in units the minimum value you expect to
measure.
• max_val (Optional[float]) – Specifies in units the maximum value you expect to
measure.
• units (Optional[nidaqmx.constants.TemperatureUnits]) – Specifies
the units to use to return temperature measurements.
• resistance_config
(Optional[nidaqmx.constants.
ResistanceConfiguration]) – Specifies the number of wires to use for
resistive measurements.
• current_excit_source
(Optional[nidaqmx.constants.
ExcitationSource]) – Specifies the source of excitation.

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• current_excit_val (Optional[float]) – Specifies in amperes the amount of
excitation to supply to the sensor. Refer to the sensor documentation to determine this
value.
Returns Indicates the newly created channel object.
Return type nidaqmx._task_modules.channels.ai_channel.AIChannel
add_teds_ai_strain_gage_chan(physical_channel,
name_to_assign_to_channel=u’‘,
min_val=-0.001,
max_val=0.001,
units=,
voltage_excit_source=,
voltage_excit_val=2.5,
initial_bridge_voltage=0.0,
lead_wire_resistance=0.0, custom_scale_name=u’‘)
Creates channel(s) to measure strain. You must configure the physical channel(s) with TEDS information
to use this function.
Parameters
• physical_channel (str) – Specifies the names of the physical channels to use to
create virtual channels. The DAQmx physical channel constant lists all physical channels
on devices and modules installed in the system.
• name_to_assign_to_channel (Optional[str]) – Specifies a name to assign
to the virtual channel this function creates. If you do not specify a value for this input,
NI-DAQmx uses the physical channel name as the virtual channel name.
• min_val (Optional[float]) – Specifies in units the minimum value you expect to
measure.
• max_val (Optional[float]) – Specifies in units the maximum value you expect to
measure.
• units (Optional[nidaqmx.constants.StrainUnits]) – Specifies the units
to use to return strain measurements.
• voltage_excit_source
(Optional[nidaqmx.constants.
ExcitationSource]) – Specifies information about the bridge configuration
and measurement.
• voltage_excit_val (Optional[float]) – Specifies information about the
bridge configuration and measurement.
• initial_bridge_voltage (Optional[float]) – Specifies information about
the bridge configuration and measurement.
• lead_wire_resistance (Optional[float]) – Specifies information about the
bridge configuration and measurement.
• custom_scale_name (Optional[str]) – Specifies the name of a custom scale for
the channel. If you want the channel to use a custom scale, specify the name of the custom
scale to this input and set units to FROM_CUSTOM_SCALE.
Returns Indicates the newly created channel object.
Return type nidaqmx._task_modules.channels.ai_channel.AIChannel
add_teds_ai_thrmcpl_chan(physical_channel, name_to_assign_to_channel=u’‘, min_val=0.0,
max_val=100.0,
units=,
cjc_source=,
cjc_val=25.0, cjc_channel=u’‘)
Creates channel(s) that use a thermocouple to measure temperature. You must configure the physical
channel(s) with TEDS information to use this function.
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Parameters
• physical_channel (str) – Specifies the names of the physical channels to use to
create virtual channels. The DAQmx physical channel constant lists all physical channels
on devices and modules installed in the system.
• name_to_assign_to_channel (Optional[str]) – Specifies a name to assign
to the virtual channel this function creates. If you do not specify a value for this input,
NI-DAQmx uses the physical channel name as the virtual channel name.
• min_val (Optional[float]) – Specifies in units the minimum value you expect to
measure.
• max_val (Optional[float]) – Specifies in units the maximum value you expect to
measure.
• units (Optional[nidaqmx.constants.TemperatureUnits]) – Specifies
the units to use to return temperature measurements.
• cjc_source (Optional[nidaqmx.constants.CJCSource]) – Specifies the
source of cold-junction compensation.
• cjc_val (Optional[float]) – Specifies in units the temperature of the cold junction if you set cjc_source to CONSTANT_VALUE.
• cjc_channel (Optional[str]) – Specifies the channel that acquires the temperature of the thermocouple cold- junction if you set cjc_source to CHANNEL.
Returns Indicates the newly created channel object.
Return type nidaqmx._task_modules.channels.ai_channel.AIChannel
add_teds_ai_thrmstr_chan_iex(physical_channel,
name_to_assign_to_channel=u’‘,
min_val=0.0,
max_val=100.0,
units=,
resistance_config=, current_excit_source=, current_excit_val=0.00015)
Creates channel(s) that use a thermistor to measure temperature. Use this instance when the thermistor
requires current excitation. You must configure the physical channel(s) with TEDS information to use this
function.
Parameters
• physical_channel (str) – Specifies the names of the physical channels to use to
create virtual channels. The DAQmx physical channel constant lists all physical channels
on devices and modules installed in the system.
• name_to_assign_to_channel (Optional[str]) – Specifies a name to assign
to the virtual channel this function creates. If you do not specify a value for this input,
NI-DAQmx uses the physical channel name as the virtual channel name.
• min_val (Optional[float]) – Specifies in units the minimum value you expect to
measure.
• max_val (Optional[float]) – Specifies in units the maximum value you expect to
measure.
• units (Optional[nidaqmx.constants.TemperatureUnits]) – Specifies
the units to use to return temperature measurements.

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• resistance_config
(Optional[nidaqmx.constants.
ResistanceConfiguration]) – Specifies the number of wires to use for
resistive measurements.
• current_excit_source
(Optional[nidaqmx.constants.
ExcitationSource]) – Specifies the source of excitation.
• current_excit_val (Optional[float]) – Specifies in amperes the amount of
excitation to supply to the sensor. Refer to the sensor documentation to determine this
value.
Returns Indicates the newly created channel object.
Return type nidaqmx._task_modules.channels.ai_channel.AIChannel
add_teds_ai_thrmstr_chan_vex(physical_channel,
name_to_assign_to_channel=u’‘,
min_val=0.0,
max_val=100.0,
units=,
resistance_config=, voltage_excit_source=, voltage_excit_val=2.5, r_1=5000.0)
Creates channel(s) that use a thermistor to measure temperature. Use this instance when the thermistor
requires voltage excitation. You must configure the physical channel(s) with TEDS information to use this
function.
Parameters
• physical_channel (str) – Specifies the names of the physical channels to use to
create virtual channels. The DAQmx physical channel constant lists all physical channels
on devices and modules installed in the system.
• name_to_assign_to_channel (Optional[str]) – Specifies a name to assign
to the virtual channel this function creates. If you do not specify a value for this input,
NI-DAQmx uses the physical channel name as the virtual channel name.
• min_val (Optional[float]) – Specifies in units the minimum value you expect to
measure.
• max_val (Optional[float]) – Specifies in units the maximum value you expect to
measure.
• units (Optional[nidaqmx.constants.TemperatureUnits]) – Specifies
the units to use to return temperature measurements.
• resistance_config
(Optional[nidaqmx.constants.
ResistanceConfiguration]) – Specifies the number of wires to use for
resistive measurements.
• voltage_excit_source
(Optional[nidaqmx.constants.
ExcitationSource]) – Specifies the source of excitation.
• voltage_excit_val (Optional[float]) – Specifies in volts the amount of excitation supplied to the sensor. Refer to the sensor documentation to determine appropriate
excitation values.
• r_1 (Optional[float]) – Specifies in ohms the value of the reference resistor.
Returns Indicates the newly created channel object.
Return type nidaqmx._task_modules.channels.ai_channel.AIChannel

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add_teds_ai_torque_bridge_chan(physical_channel,
name_to_assign_to_channel=u’‘,
min_val=-100.0,
max_val=100.0,
units=,
voltage_excit_source=, voltage_excit_val=2.5, custom_scale_name=u’‘)
Creates channel(s) that use a Wheatstone bridge to measure torque. You must configure the physical
channel(s) with TEDS information to use this function. NI-DAQmx scales electrical values to physical
values according to that TEDS information.
Parameters
• physical_channel (str) – Specifies the names of the physical channels to use to
create virtual channels. The DAQmx physical channel constant lists all physical channels
on devices and modules installed in the system.
• name_to_assign_to_channel (Optional[str]) – Specifies a name to assign
to the virtual channel this function creates. If you do not specify a value for this input,
NI-DAQmx uses the physical channel name as the virtual channel name.
• min_val (Optional[float]) – Specifies in units the minimum value you expect to
measure.
• max_val (Optional[float]) – Specifies in units the maximum value you expect to
measure.
• units (Optional[nidaqmx.constants.TorqueUnits]) – Specifies in which
unit to return torque measurements from the channel.
• voltage_excit_source
(Optional[nidaqmx.constants.
ExcitationSource]) – Specifies the source of excitation.
• voltage_excit_val (Optional[float]) – Specifies in volts the amount of excitation supplied to the sensor. Refer to the sensor documentation to determine appropriate
excitation values.
• custom_scale_name (Optional[str]) – Specifies the name of a custom scale for
the channel. If you want the channel to use a custom scale, specify the name of the custom
scale to this input and set units to FROM_CUSTOM_SCALE.
Returns Indicates the newly created channel object.
Return type nidaqmx._task_modules.channels.ai_channel.AIChannel
add_teds_ai_voltage_chan(physical_channel,
name_to_assign_to_channel=u’‘,
terminal_config=, min_val=5.0, max_val=5.0, units=,
custom_scale_name=u’‘)
Creates channel(s) to measure voltage. You must configure the physical channel(s) with TEDS information
to use this function. If the measurement requires the use of internal excitation or you need excitation to
scale the voltage, use the TEDS AI Custom Voltage with Excitation instance of this function.
Parameters
• physical_channel (str) – Specifies the names of the physical channels to use to
create virtual channels. The DAQmx physical channel constant lists all physical channels
on devices and modules installed in the system.
• name_to_assign_to_channel (Optional[str]) – Specifies a name to assign
to the virtual channel this function creates. If you do not specify a value for this input,
NI-DAQmx uses the physical channel name as the virtual channel name.

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• terminal_config
(Optional[nidaqmx.constants.
TerminalConfiguration]) – Specifies the input terminal configuration for
the channel.
• min_val (Optional[float]) – Specifies in units the minimum value you expect to
measure.
• max_val (Optional[float]) – Specifies in units the maximum value you expect to
measure.
• units (Optional[nidaqmx.constants.TEDSUnits]) – Specifies the units to
use to return measurements.
• custom_scale_name (Optional[str]) – Specifies the name of a custom scale for
the channel. If you want the channel to use a custom scale, specify the name of the custom
scale to this input and set units to FROM_CUSTOM_SCALE.
Returns Indicates the newly created channel object.
Return type nidaqmx._task_modules.channels.ai_channel.AIChannel
add_teds_ai_voltage_chan_with_excit(physical_channel, name_to_assign_to_channel=u’‘,
terminal_config=,
min_val=-10.0,
max_val=10.0,
units=, voltage_excit_source=,
voltage_excit_val=0.0,
custom_scale_name=u’‘)
Creates channel(s) to measure voltage. Use this instance for custom sensors that require excitation. You
can use the excitation to scale the measurement. You must configure the physical channel(s) with TEDS
information to use this function.
Parameters
• physical_channel (str) – Specifies the names of the physical channels to use to
create virtual channels. The DAQmx physical channel constant lists all physical channels
on devices and modules installed in the system.
• name_to_assign_to_channel (Optional[str]) – Specifies a name to assign
to the virtual channel this function creates. If you do not specify a value for this input,
NI-DAQmx uses the physical channel name as the virtual channel name.
• terminal_config
(Optional[nidaqmx.constants.
TerminalConfiguration]) – Specifies the input terminal configuration for
the channel.
• min_val (Optional[float]) – Specifies in units the minimum value you expect to
measure.
• max_val (Optional[float]) – Specifies in units the maximum value you expect to
measure.
• units (Optional[nidaqmx.constants.TEDSUnits]) – Specifies the units to
use to return measurements.
• voltage_excit_source
(Optional[nidaqmx.constants.
ExcitationSource]) – Specifies the source of excitation.
• voltage_excit_val (Optional[float]) – Specifies in volts the amount of excitation supplied to the sensor. Refer to the sensor documentation to determine appropriate
excitation values.

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• custom_scale_name (Optional[str]) – Specifies the name of a custom scale for
the channel. If you want the channel to use a custom scale, specify the name of the custom
scale to this input and set units to FROM_CUSTOM_SCALE.
Returns Indicates the newly created channel object.
Return type nidaqmx._task_modules.channels.ai_channel.AIChannel
all
nidaqmx._task_modules.channels.channel.Channel – Specifies a channel object that represents the entire list of virtual channels on this channel collection.
channel_names
List[str] – Specifies the entire list of virtual channels on this channel collection.
count(value) → integer – return number of occurrences of value
index(value) → integer – return first index of value.
Raises ValueError if the value is not present.
nidaqmx.task.ao_channel_collection
class nidaqmx._task_modules.ao_channel_collection.AOChannelCollection(task_handle)
Bases: nidaqmx._task_modules.channel_collection.ChannelCollection
Contains the collection of analog output channels for a DAQmx Task.
add_ao_current_chan(physical_channel,
name_to_assign_to_channel=u’‘,
min_val=0.0,
max_val=0.02,
units=,
custom_scale_name=u’‘)
Creates channel(s) to generate current.
Parameters
• physical_channel (str) – Specifies the names of the physical channels to use to
create virtual channels. The DAQmx physical channel constant lists all physical channels
on devices and modules installed in the system.
• name_to_assign_to_channel (Optional[str]) – Specifies a name to assign
to the virtual channel this function creates. If you do not specify a value for this input,
NI-DAQmx uses the physical channel name as the virtual channel name.
• min_val (Optional[float]) – Specifies in units the minimum value you expect to
measure.
• max_val (Optional[float]) – Specifies in units the maximum value you expect to
measure.
• units (Optional[nidaqmx.constants.CurrentUnits]) – Specifies the
units to use to generate current.
• custom_scale_name (Optional[str]) – Specifies the name of a custom scale for
the channel. If you want the channel to use a custom scale, specify the name of the custom
scale to this input and set units to FROM_CUSTOM_SCALE.
Returns Indicates the newly created channel object.
Return type nidaqmx._task_modules.channels.ao_channel.AOChannel
add_ao_func_gen_chan(physical_channel,
name_to_assign_to_channel=u’‘,
type=, freq=1000.0, amplitude=5.0,
offset=0.0)
Creates a channel for continually generating a waveform on the selected physical channel.
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Parameters
• physical_channel (str) – Specifies the names of the physical channels to use to
create virtual channels. The DAQmx physical channel constant lists all physical channels
on devices and modules installed in the system.
• name_to_assign_to_channel (Optional[str]) – Specifies a name to assign
to the virtual channel this function creates. If you do not specify a value for this input,
NI-DAQmx uses the physical channel name as the virtual channel name.
• type (Optional[nidaqmx.constants.FuncGenType]) – Specifies the kind of
waveform to generate.
• freq (Optional[float]) – Is the frequency of the waveform to generate in hertz.
• amplitude (Optional[float]) – Is the zero-to-peak amplitude of the waveform to
generate in volts. Zero and negative values are valid.
• offset (Optional[float]) – Is the voltage offset of the waveform to generate.
Returns Indicates the newly created channel object.
Return type nidaqmx._task_modules.channels.ao_channel.AOChannel
add_ao_voltage_chan(physical_channel,
name_to_assign_to_channel=u’‘,
min_val=10.0, max_val=10.0, units=, custom_scale_name=u’‘)
Creates channel(s) to generate voltage.
Parameters
• physical_channel (str) – Specifies the names of the physical channels to use to
create virtual channels. The DAQmx physical channel constant lists all physical channels
on devices and modules installed in the system.
• name_to_assign_to_channel (Optional[str]) – Specifies a name to assign
to the virtual channel this function creates. If you do not specify a value for this input,
NI-DAQmx uses the physical channel name as the virtual channel name.
• min_val (Optional[float]) – Specifies in units the minimum value you expect to
generate.
• max_val (Optional[float]) – Specifies in units the maximum value you expect to
generate.
• units (Optional[nidaqmx.constants.VoltageUnits]) – Specifies the
units to use to generate voltage.
• custom_scale_name (Optional[str]) – Specifies the name of a custom scale for
the channel. If you want the channel to use a custom scale, specify the name of the custom
scale to this input and set units to FROM_CUSTOM_SCALE.
Returns Indicates the newly created channel object.
Return type nidaqmx._task_modules.channels.ao_channel.AOChannel
all
nidaqmx._task_modules.channels.channel.Channel – Specifies a channel object that represents the entire list of virtual channels on this channel collection.
channel_names
List[str] – Specifies the entire list of virtual channels on this channel collection.
count(value) → integer – return number of occurrences of value

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index(value) → integer – return first index of value.
Raises ValueError if the value is not present.
nidaqmx.task.ci_channel_collection
class nidaqmx._task_modules.ci_channel_collection.CIChannelCollection(task_handle)
Bases: nidaqmx._task_modules.channel_collection.ChannelCollection
Contains the collection of counter input channels for a DAQmx Task.
add_ci_ang_encoder_chan(counter,
name_to_assign_to_channel=u’‘,
decoding_type=,
zidx_enable=False,
zidx_val=0, zidx_phase=,
units=,
pulses_per_rev=24, initial_angle=0.0, custom_scale_name=u’‘)
Creates a channel that uses an angular encoder to measure angular position. With the exception of devices
that support multi-counter tasks, you can create only one counter input channel at a time with this function
because a task can contain only one counter input channel. To read from multiple counters simultaneously,
use a separate task for each counter. Connect the input signals to the default input terminals of the counter
unless you select different input terminals.
Parameters
• counter (str) – Specifies the name of the counter to use to create the virtual channel.
The DAQmx physical channel constant lists all physical channels, including counters, for
devices installed in the system.
• name_to_assign_to_channel (Optional[str]) – Specifies a name to assign
to the virtual channel this function creates. If you do not specify a value for this input,
NI-DAQmx uses the physical channel name as the virtual channel name.
• decoding_type (Optional[nidaqmx.constants.EncoderType]) – Specifies how to count and interpret the pulses the encoder generates on signal A and signal B.
X_1, X_2, and X_4 are valid for quadrature encoders only. TWO_PULSE_COUNTING
is valid only for two-pulse encoders.
• zidx_enable (Optional[bool]) – Specifies whether to use Z indexing for the
channel.
• zidx_val (Optional[float]) – Specifies in units the value to which to reset the
measurement when signal Z is high and signal A and signal B are at the states you specify
with zidx_phase.
• zidx_phase (Optional[nidaqmx.constants.EncoderZIndexPhase]) –
Specifies the states at which signal A and signal B must be while signal Z is high for
NI-DAQmx to reset the measurement. If signal Z is never high while signal A and signal
B are high, for example, you must choose a phase other than A_HIGH_B_HIGH.
• units (Optional[nidaqmx.constants.AngleUnits]) – Specifies the units to
use to return angular position measurements from the channel.
• pulses_per_rev (Optional[int]) – Is the number of pulses the encoder generates
per revolution. This value is the number of pulses on either signal A or signal B, not the
total number of pulses on both signal A and signal B.
• initial_angle (Optional[float]) – Is the starting angle of the encoder. This
value is in the units you specify with the units input.

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• custom_scale_name (Optional[str]) – Specifies the name of a custom scale for
the channel. If you want the channel to use a custom scale, specify the name of the custom
scale to this input and set units to FROM_CUSTOM_SCALE.
Returns Indicates the newly created channel object.
Return type nidaqmx._task_modules.channels.ci_channel.CIChannel
add_ci_ang_velocity_chan(counter,
name_to_assign_to_channel=u’‘,
min_val=0.0,
max_val=1.0, decoding_type=,
units=, pulses_per_rev=24,
custom_scale_name=u’‘)
Creates a channel to measure the angular velocity of a digital signal. With the exception of devices that
support multi-counter tasks, you can create only one counter input channel at a time with this function
because a task can contain only one counter input channel. To read from multiple counters simultaneously,
use a separate task for each counter. Connect the input signal to the default input terminal of the counter
unless you select a different input terminal.
Parameters
• counter (str) – Specifies the name of the counter to use to create the virtual channel.
The DAQmx physical channel constant lists all physical channels, including counters, for
devices installed in the system.
• name_to_assign_to_channel (Optional[str]) – Specifies a name to assign
to the virtual channel this function creates. If you do not specify a value for this input,
NI-DAQmx uses the physical channel name as the virtual channel name.
• min_val (Optional[float]) – Specifies in units the minimum value you expect to
measure.
• max_val (Optional[float]) – Specifies in units the maximum value you expect to
measure.
• decoding_type (Optional[nidaqmx.constants.EncoderType]) – Specifies how to count and interpret the pulses the encoder generates on signal A and signal B.
X_1, X_2, and X_4 are valid for quadrature encoders only. TWO_PULSE_COUNTING
is valid only for two-pulse encoders.
• units (Optional[nidaqmx.constants.AngularVelocityUnits]) – Specifies in which unit to return velocity measurements from the channel.
• pulses_per_rev (Optional[int]) – Is the number of pulses the encoder generates
per revolution. This value is the number of pulses on either signal A or signal B, not the
total number of pulses on both signal A and signal B.
• custom_scale_name (Optional[str]) – Specifies the name of a custom scale for
the channel. If you want the channel to use a custom scale, specify the name of the custom
scale to this input and set units to FROM_CUSTOM_SCALE.
Returns Indicates the newly created channel object.
Return type nidaqmx._task_modules.channels.ci_channel.CIChannel
add_ci_count_edges_chan(counter,
name_to_assign_to_channel=u’‘,
edge=,
initial_count=0,
count_direction=)
Creates a channel to count the number of rising or falling edges of a digital signal. With the exception
of devices that support multi-counter tasks, you can create only one counter input channel at a time with
this function because a task can contain only one counter input channel. To read from multiple counters
simultaneously, use a separate task for each counter. Connect the input signal to the default input terminal
of the counter unless you select a different input terminal.
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Parameters
• counter (str) – Specifies the name of the counter to use to create the virtual channel.
The DAQmx physical channel constant lists all physical channels, including counters, for
devices installed in the system.
• name_to_assign_to_channel (Optional[str]) – Specifies a name to assign
to the virtual channel this function creates. If you do not specify a value for this input,
NI-DAQmx uses the physical channel name as the virtual channel name.
• edge (Optional[nidaqmx.constants.Edge]) – Specifies on which edges of the
input signal to increment or decrement the count.
• initial_count (Optional[int]) – Is the value from which to start counting.
• count_direction (Optional[nidaqmx.constants.CountDirection]) –
Specifies whether to increment or decrement the counter on each edge.
Returns Indicates the newly created channel object.
Return type nidaqmx._task_modules.channels.ci_channel.CIChannel
add_ci_duty_cycle_chan(counter,
name_to_assign_to_channel=u’‘,
min_freq=2.0,
max_freq=10000.0,
edge=,
custom_scale_name=u’‘)
Creates channel(s) to duty cycle of a digital pulse. Connect the input signal to the default input terminal of
the counter unless you select a different input terminal. With the exception of devices that support multicounter tasks, you can create only one counter input channel at a time with this function because a task
can contain only one counter input channel. To read from multiple counters simultaneously, use a separate
task for each counter.
Parameters
• counter (str) – Specifies the name of the counter to use to create the virtual channel.
The DAQmx physical channel constant lists all physical channels, including counters, for
devices installed in the system.
• name_to_assign_to_channel (Optional[str]) – Specifies a name to assign
to the virtual channel this function creates. If you do not specify a value for this input,
NI-DAQmx uses the physical channel name as the virtual channel name.
• min_freq (Optional[float]) – Specifies the minimum frequency you expect to
measure.
• max_freq (Optional[float]) – Specifies the maximum frequency you expect to
measure.
• edge (Optional[nidaqmx.constants.Edge]) – Specifies between which edges
to measure the frequency or period of the signal.
• custom_scale_name (Optional[str]) – Specifies the name of a custom scale for
the channel. If you want the channel to use a custom scale, specify the name of the custom
scale to this input and set units to FROM_CUSTOM_SCALE.
Returns Indicates the newly created channel object.
Return type nidaqmx._task_modules.channels.ci_channel.CIChannel
add_ci_freq_chan(counter, name_to_assign_to_channel=u’‘, min_val=2.0, max_val=100.0,
units=,
edge=,
meas_method=, meas_time=0.001, divisor=4, custom_scale_name=u’‘)
Creates a channel to measure the frequency of a digital signal. With the exception of devices that support

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multi-counter tasks, you can create only one counter input channel at a time with this function because
a task can contain only one counter input channel. To read from multiple counters simultaneously, use a
separate task for each counter. Connect the input signal to the default input terminal of the counter unless
you select a different input terminal.
Parameters
• counter (str) – Specifies the name of the counter to use to create the virtual channel.
The DAQmx physical channel constant lists all physical channels, including counters, for
devices installed in the system.
• name_to_assign_to_channel (Optional[str]) – Specifies a name to assign
to the virtual channel this function creates. If you do not specify a value for this input,
NI-DAQmx uses the physical channel name as the virtual channel name.
• min_val (Optional[float]) – Specifies in units the minimum value you expect to
measure.
• max_val (Optional[float]) – Specifies in units the maximum value you expect to
measure.
• units (Optional[nidaqmx.constants.FrequencyUnits]) – Specifies the
units to use to return frequency measurements.
• edge (Optional[nidaqmx.constants.Edge]) – Specifies between which edges
to measure the frequency or period of the signal.
• meas_method
(Optional[nidaqmx.constants.
CounterFrequencyMethod]) – Specifies the method to use to calculate the
period or frequency of the signal.
• meas_time (Optional[float]) – Is the length of time in seconds
to measure the frequency or period of the signal if meas_method is
HIGH_FREQUENCYWITH_2_COUNTERS. Leave this input unspecified if
meas_method is not HIGH_FREQUENCYWITH_2_COUNTERS.
• divisor (Optional[int]) – Is the value by which to divide the input signal when
meas_method is LARGE_RANGEWITH_2_COUNTERS. Leave this input unspecified if meas_method is not LARGE_RANGEWITH_2_COUNTERS.
• custom_scale_name (Optional[str]) – Specifies the name of a custom scale for
the channel. If you want the channel to use a custom scale, specify the name of the custom
scale to this input and set units to FROM_CUSTOM_SCALE.
Returns Indicates the newly created channel object.
Return type nidaqmx._task_modules.channels.ci_channel.CIChannel
add_ci_gps_timestamp_chan(counter,
name_to_assign_to_channel=u’‘,
units=,
sync_method=,
custom_scale_name=u’‘)
Creates a channel that uses a special purpose counter to take a timestamp and synchronizes that counter
to a GPS receiver. With the exception of devices that support multi-counter tasks, you can create only
one counter input channel at a time with this function because a task can contain only one counter input
channel. To read from multiple counters simultaneously, use a separate task for each counter. Connect the
input signals to the default input terminals of the counter unless you select different input terminals.
Parameters

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• counter (str) – Specifies the name of the counter to use to create the virtual channel.
The DAQmx physical channel constant lists all physical channels, including counters, for
devices installed in the system.
• name_to_assign_to_channel (Optional[str]) – Specifies a name to assign
to the virtual channel this function creates. If you do not specify a value for this input,
NI-DAQmx uses the physical channel name as the virtual channel name.
• units (Optional[nidaqmx.constants.TimeUnits]) – Specifies the units to
use to return the timestamp.
• sync_method (Optional[nidaqmx.constants.GpsSignalType]) – Specifies the method to use to synchronize the counter to a GPS receiver.
• custom_scale_name (Optional[str]) – Specifies the name of a custom scale for
the channel. If you want the channel to use a custom scale, specify the name of the custom
scale to this input and set units to FROM_CUSTOM_SCALE.
Returns Indicates the newly created channel object.
Return type nidaqmx._task_modules.channels.ci_channel.CIChannel
add_ci_lin_encoder_chan(counter,
name_to_assign_to_channel=u’‘,
decoding_type=,
zidx_enable=False,
zidx_val=0, zidx_phase=,
units=,
dist_per_pulse=0.001, initial_pos=0.0, custom_scale_name=u’‘)
Creates a channel that uses a linear encoder to measure linear position. With the exception of devices that
support multi- counter tasks, you can create only one counter input channel at a time with this function
because a task can contain only one counter input channel. To read from multiple counters simultaneously,
use a separate task for each counter. Connect the input signals to the default input terminals of the counter
unless you select different input terminals.
Parameters
• counter (str) – Specifies the name of the counter to use to create the virtual channel.
The DAQmx physical channel constant lists all physical channels, including counters, for
devices installed in the system.
• name_to_assign_to_channel (Optional[str]) – Specifies a name to assign
to the virtual channel this function creates. If you do not specify a value for this input,
NI-DAQmx uses the physical channel name as the virtual channel name.
• decoding_type (Optional[nidaqmx.constants.EncoderType]) – Specifies how to count and interpret the pulses the encoder generates on signal A and signal B.
X_1, X_2, and X_4 are valid for quadrature encoders only. TWO_PULSE_COUNTING
is valid only for two-pulse encoders.
• zidx_enable (Optional[bool]) – Specifies whether to use Z indexing for the
channel.
• zidx_val (Optional[float]) – Specifies in units the value to which to reset the
measurement when signal Z is high and signal A and signal B are at the states you specify
with zidx_phase.
• zidx_phase (Optional[nidaqmx.constants.EncoderZIndexPhase]) –
Specifies the states at which signal A and signal B must be while signal Z is high for
NI-DAQmx to reset the measurement. If signal Z is never high while signal A and signal
B are high, for example, you must choose a phase other than A_HIGH_B_HIGH.
• units (Optional[nidaqmx.constants.LengthUnits]) – Specifies the units
to use to return linear position measurements from the channel.
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• dist_per_pulse (Optional[float]) – Is the distance to measure for each pulse
the encoder generates on signal A or signal B. This value is in the units you specify with
the units input.
• initial_pos (Optional[float]) – Is the position of the encoder when you begin
the measurement. This value is in the units you specify with the units input.
• custom_scale_name (Optional[str]) – Specifies the name of a custom scale for
the channel. If you want the channel to use a custom scale, specify the name of the custom
scale to this input and set units to FROM_CUSTOM_SCALE.
Returns Indicates the newly created channel object.
Return type nidaqmx._task_modules.channels.ci_channel.CIChannel
add_ci_lin_velocity_chan(counter,
name_to_assign_to_channel=u’‘,
min_val=0.0,
max_val=1.0, decoding_type=,
units=,
dist_per_pulse=0.001, custom_scale_name=u’‘)
Creates a channel that uses a linear encoder to measure linear velocity. With the exception of devices that
support multi- counter tasks, you can create only one counter input channel at a time with this function
because a task can contain only one counter input channel. To read from multiple counters simultaneously,
use a separate task for each counter. Connect the input signal to the default input terminal of the counter
unless you select a different input terminal.
Parameters
• counter (str) – Specifies the name of the counter to use to create the virtual channel.
The DAQmx physical channel constant lists all physical channels, including counters, for
devices installed in the system.
• name_to_assign_to_channel (Optional[str]) – Specifies a name to assign
to the virtual channel this function creates. If you do not specify a value for this input,
NI-DAQmx uses the physical channel name as the virtual channel name.
• min_val (Optional[float]) – Specifies in units the minimum value you expect to
measure.
• max_val (Optional[float]) – Specifies in units the maximum value you expect to
measure.
• decoding_type (Optional[nidaqmx.constants.EncoderType]) – Specifies how to count and interpret the pulses the encoder generates on signal A and signal B.
X_1, X_2, and X_4 are valid for quadrature encoders only. TWO_PULSE_COUNTING
is valid only for two-pulse encoders.
• units (Optional[nidaqmx.constants.VelocityUnits]) – Specifies in
which unit to return velocity measurements from the channel.
• dist_per_pulse (Optional[float]) – Is the distance to measure for each pulse
the encoder generates on signal A or signal B. This value is in the units you specify with
the units input.
• custom_scale_name (Optional[str]) – Specifies the name of a custom scale for
the channel. If you want the channel to use a custom scale, specify the name of the custom
scale to this input and set units to FROM_CUSTOM_SCALE.
Returns Indicates the newly created channel object.
Return type nidaqmx._task_modules.channels.ci_channel.CIChannel

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add_ci_period_chan(counter, name_to_assign_to_channel=u’‘, min_val=1e-06, max_val=0.1,
units=, edge=,
meas_method=, meas_time=0.001, divisor=4, custom_scale_name=u’‘)
Creates a channel to measure the period of a digital signal. With the exception of devices that support
multi-counter tasks, you can create only one counter input channel at a time with this function because
a task can contain only one counter input channel. To read from multiple counters simultaneously, use a
separate task for each counter. Connect the input signal to the default input terminal of the counter unless
you select a different input terminal.
Parameters
• counter (str) – Specifies the name of the counter to use to create the virtual channel.
The DAQmx physical channel constant lists all physical channels, including counters, for
devices installed in the system.
• name_to_assign_to_channel (Optional[str]) – Specifies a name to assign
to the virtual channel this function creates. If you do not specify a value for this input,
NI-DAQmx uses the physical channel name as the virtual channel name.
• min_val (Optional[float]) – Specifies in units the minimum value you expect to
measure.
• max_val (Optional[float]) – Specifies in units the maximum value you expect to
measure.
• units (Optional[nidaqmx.constants.TimeUnits]) – Specifies the units to
use to return time or period measurements.
• edge (Optional[nidaqmx.constants.Edge]) – Specifies between which edges
to measure the frequency or period of the signal.
• meas_method
(Optional[nidaqmx.constants.
CounterFrequencyMethod]) – Specifies the method to use to calculate the
period or frequency of the signal.
• meas_time (Optional[float]) – Is the length of time in seconds
to measure the frequency or period of the signal if meas_method is
HIGH_FREQUENCYWITH_2_COUNTERS. Leave this input unspecified if
meas_method is not HIGH_FREQUENCYWITH_2_COUNTERS.
• divisor (Optional[int]) – Is the value by which to divide the input signal when
meas_method is LARGE_RANGEWITH_2_COUNTERS. Leave this input unspecified if meas_method is not LARGE_RANGEWITH_2_COUNTERS.
• custom_scale_name (Optional[str]) – Specifies the name of a custom scale for
the channel. If you want the channel to use a custom scale, specify the name of the custom
scale to this input and set units to FROM_CUSTOM_SCALE.
Returns Indicates the newly created channel object.
Return type nidaqmx._task_modules.channels.ci_channel.CIChannel
add_ci_pulse_chan_freq(counter,
name_to_assign_to_channel=u’‘,
min_val=1000,
max_val=1000000, units=)
Creates a channel to measure pulse specifications, returning the measurements as pairs of frequency and
duty cycle. With the exception of devices that support multi-counter tasks, you can create only one counter
input channel at a time with this function because a task can contain only one counter input channel. To
read from multiple counters simultaneously, use a separate task for each counter. Connect the input signal
to the default input terminal of the counter unless you select a different input terminal.
Parameters
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• counter (str) – Specifies the name of the counter to use to create the virtual channel.
The DAQmx physical channel constant lists all physical channels, including counters, for
devices installed in the system.
• name_to_assign_to_channel (Optional[str]) – Specifies a name to assign
to the virtual channel this function creates. If you do not specify a value for this input,
NI-DAQmx uses the physical channel name as the virtual channel name.
• min_val (Optional[float]) – Specifies in units the minimum value you expect to
measure.
• max_val (Optional[float]) – Specifies in units the maximum value you expect to
measure.
• units (Optional[nidaqmx.constants.FrequencyUnits]) – Specifies the
units to use to return pulse specifications in terms of frequency.
Returns Indicates the newly created channel object.
Return type nidaqmx._task_modules.channels.ci_channel.CIChannel
add_ci_pulse_chan_ticks(counter,
name_to_assign_to_channel=u’‘,
source_terminal=u’OnboardClock’,
min_val=1000,
max_val=1000000)
Creates a channel to measure pulse specifications, returning the measurements as pairs of high ticks and
low ticks. With the exception of devices that support multi-counter tasks, you can create only one counter
input channel at a time with this function because a task can contain only one counter input channel. To
read from multiple counters simultaneously, use a separate task for each counter. Connect the input signal
to the default input terminal of the counter unless you select a different input terminal.
Parameters
• counter (str) – Specifies the name of the counter to use to create the virtual channel.
The DAQmx physical channel constant lists all physical channels, including counters, for
devices installed in the system.
• name_to_assign_to_channel (Optional[str]) – Specifies a name to assign
to the virtual channel this function creates. If you do not specify a value for this input,
NI-DAQmx uses the physical channel name as the virtual channel name.
• source_terminal (Optional[str]) – Is the terminal to which you connect a signal to use as the source of ticks. A DAQmx terminal constant lists all terminals available
on devices installed in the system. You also can specify a source terminal by specifying a
string that contains a terminal name. If you specify OnboardClock, or do not specify any
terminal, NI-DAQmx selects the fastest onboard timebase available on the device.
• min_val (Optional[float]) – Specifies in units the minimum value you expect to
measure.
• max_val (Optional[float]) – Specifies in units the maximum value you expect to
measure.
Returns Indicates the newly created channel object.
Return type nidaqmx._task_modules.channels.ci_channel.CIChannel
add_ci_pulse_chan_time(counter,
name_to_assign_to_channel=u’‘,
min_val=1e-06,
max_val=0.001, units=)
Creates a channel to measure pulse specifications, returning the measurements as pairs of high time and
low time. With the exception of devices that support multi-counter tasks, you can create only one counter
input channel at a time with this function because a task can contain only one counter input channel. To

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read from multiple counters simultaneously, use a separate task for each counter. Connect the input signal
to the default input terminal of the counter unless you select a different input terminal.
Parameters
• counter (str) – Specifies the name of the counter to use to create the virtual channel.
The DAQmx physical channel constant lists all physical channels, including counters, for
devices installed in the system.
• name_to_assign_to_channel (Optional[str]) – Specifies a name to assign
to the virtual channel this function creates. If you do not specify a value for this input,
NI-DAQmx uses the physical channel name as the virtual channel name.
• min_val (Optional[float]) – Specifies in units the minimum value you expect to
measure.
• max_val (Optional[float]) – Specifies in units the maximum value you expect to
measure.
• units (Optional[nidaqmx.constants.TimeUnits]) – Specifies the units to
use to return pulse specifications in terms of high time and low time.
Returns Indicates the newly created channel object.
Return type nidaqmx._task_modules.channels.ci_channel.CIChannel
add_ci_pulse_width_chan(counter,
name_to_assign_to_channel=u’‘,
min_val=1e-06,
max_val=0.1,
units=,
starting_edge=, custom_scale_name=u’‘)
Creates a channel to measure the width of a digital pulse. starting_edge determines whether to measure a
high pulse or low pulse. With the exception of devices that support multi- counter tasks, you can create only
one counter input channel at a time with this function because a task can contain only one counter input
channel. To read from multiple counters simultaneously, use a separate task for each counter. Connect the
input signal to the default input terminal of the counter unless you select a different input terminal.
Parameters
• counter (str) – Specifies the name of the counter to use to create the virtual channel.
The DAQmx physical channel constant lists all physical channels, including counters, for
devices installed in the system.
• name_to_assign_to_channel (Optional[str]) – Specifies a name to assign
to the virtual channel this function creates. If you do not specify a value for this input,
NI-DAQmx uses the physical channel name as the virtual channel name.
• min_val (Optional[float]) – Specifies in units the minimum value you expect to
measure.
• max_val (Optional[float]) – Specifies in units the maximum value you expect to
measure.
• units (Optional[nidaqmx.constants.TimeUnits]) – Specifies the units to
use to return time or period measurements.
• starting_edge (Optional[nidaqmx.constants.Edge]) – Specifies on
which edge to begin measuring pulse width.
• custom_scale_name (Optional[str]) – Specifies the name of a custom scale for
the channel. If you want the channel to use a custom scale, specify the name of the custom
scale to this input and set units to FROM_CUSTOM_SCALE.
Returns Indicates the newly created channel object.
Return type nidaqmx._task_modules.channels.ci_channel.CIChannel
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add_ci_semi_period_chan(counter,
name_to_assign_to_channel=u’‘,
min_val=1e-06,
max_val=0.1,
units=,
custom_scale_name=u’‘)
Creates a channel to measure the time between state transitions of a digital signal. With the exception
of devices that support multi-counter tasks, you can create only one counter input channel at a time with
this function because a task can contain only one counter input channel. To read from multiple counters
simultaneously, use a separate task for each counter. Connect the input signal to the default input terminal
of the counter unless you select a different input terminal.
Parameters
• counter (str) – Specifies the name of the counter to use to create the virtual channel.
The DAQmx physical channel constant lists all physical channels, including counters, for
devices installed in the system.
• name_to_assign_to_channel (Optional[str]) – Specifies a name to assign
to the virtual channel this function creates. If you do not specify a value for this input,
NI-DAQmx uses the physical channel name as the virtual channel name.
• min_val (Optional[float]) – Specifies in units the minimum value you expect to
measure.
• max_val (Optional[float]) – Specifies in units the maximum value you expect to
measure.
• units (Optional[nidaqmx.constants.TimeUnits]) – Specifies the units to
use to return time or period measurements.
• custom_scale_name (Optional[str]) – Specifies the name of a custom scale for
the channel. If you want the channel to use a custom scale, specify the name of the custom
scale to this input and set units to FROM_CUSTOM_SCALE.
Returns Indicates the newly created channel object.
Return type nidaqmx._task_modules.channels.ci_channel.CIChannel
add_ci_two_edge_sep_chan(counter,
name_to_assign_to_channel=u’‘,
min_val=1e06,
max_val=1.0,
units=,
first_edge=,
second_edge=, custom_scale_name=u’‘)
Creates a channel that measures the amount of time between the rising or falling edge of one digital signal
and the rising or falling edge of another digital signal. With the exception of devices that support multicounter tasks, you can create only one counter input channel at a time with this function because a task
can contain only one counter input channel. To read from multiple counters simultaneously, use a separate
task for each counter. Connect the input signals to the default input terminals of the counter unless you
select different input terminals.
Parameters
• counter (str) – Specifies the name of the counter to use to create the virtual channel.
The DAQmx physical channel constant lists all physical channels, including counters, for
devices installed in the system.
• name_to_assign_to_channel (Optional[str]) – Specifies a name to assign
to the virtual channel this function creates. If you do not specify a value for this input,
NI-DAQmx uses the physical channel name as the virtual channel name.
• min_val (Optional[float]) – Specifies in units the minimum value you expect to
measure.
• max_val (Optional[float]) – Specifies in units the maximum value you expect to
measure.
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• units (Optional[nidaqmx.constants.TimeUnits]) – Specifies the units to
use to return time or period measurements.
• first_edge (Optional[nidaqmx.constants.Edge]) – Specifies on which
edge of the first signal to start each measurement.
• second_edge (Optional[nidaqmx.constants.Edge]) – Specifies on which
edge of the second signal to stop each measurement.
• custom_scale_name (Optional[str]) – Specifies the name of a custom scale for
the channel. If you want the channel to use a custom scale, specify the name of the custom
scale to this input and set units to FROM_CUSTOM_SCALE.
Returns Indicates the newly created channel object.
Return type nidaqmx._task_modules.channels.ci_channel.CIChannel
all
nidaqmx._task_modules.channels.channel.Channel – Specifies a channel object that represents the entire list of virtual channels on this channel collection.
channel_names
List[str] – Specifies the entire list of virtual channels on this channel collection.
count(value) → integer – return number of occurrences of value
index(value) → integer – return first index of value.
Raises ValueError if the value is not present.
nidaqmx.task.co_channel_collection
class nidaqmx._task_modules.co_channel_collection.COChannelCollection(task_handle)
Bases: nidaqmx._task_modules.channel_collection.ChannelCollection
Contains the collection of counter output channels for a DAQmx Task.
add_co_pulse_chan_freq(counter,
name_to_assign_to_channel=u’‘,
units=,
idle_state=, initial_delay=0.0, freq=1.0, duty_cycle=0.5)
Creates channel(s) to generate digital pulses that freq and duty_cycle define. The pulses appear on the
default output terminal of the counter unless you select a different output terminal.
Parameters
• counter (str) – Specifies the names of the counters to use to create the virtual channels.
The DAQmx physical channel constant lists all physical channels, including counters, for
devices installed in the system.
• name_to_assign_to_channel (Optional[str]) – Specifies a name to assign
to the virtual channel this function creates. If you do not specify a value for this input,
NI-DAQmx uses the physical channel name as the virtual channel name.
• units (Optional[nidaqmx.constants.FrequencyUnits]) – Specifies the
units in which to define pulse frequency.
• idle_state (Optional[nidaqmx.constants.Level]) – Specifies the resting
state of the output terminal.
• initial_delay (Optional[float]) – Is the amount of time in seconds to wait
before generating the first pulse.
• freq (Optional[float]) – Specifies at what frequency to generate pulses.

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• duty_cycle (Optional[float]) – Is the width of the pulse divided by the pulse
period. NI-DAQmx uses this ratio combined with frequency to determine pulse width and
the interval between pulses.
Returns Indicates the newly created channel object.
Return type nidaqmx._task_modules.channels.co_channel.COChannel
add_co_pulse_chan_ticks(counter,
source_terminal,
name_to_assign_to_channel=u’‘,
idle_state=, initial_delay=0, low_ticks=100,
high_ticks=100)
Creates channel(s) to generate digital pulses defined by the number of timebase ticks that the pulse is at a
high state and the number of timebase ticks that the pulse is at a low state. The pulses appear on the default
output terminal of the counter unless you select a different output terminal.
Parameters
• counter (str) – Specifies the names of the counters to use to create the virtual channels.
The DAQmx physical channel constant lists all physical channels, including counters, for
devices installed in the system.
• source_terminal (str) – Is the terminal to which you connect an external timebase.
A DAQmx terminal constant lists all terminals available on devices installed in the system.
You also can specify a source terminal by specifying a string that contains a terminal name.
• name_to_assign_to_channel (Optional[str]) – Specifies a name to assign
to the virtual channel this function creates. If you do not specify a value for this input,
NI-DAQmx uses the physical channel name as the virtual channel name.
• idle_state (Optional[nidaqmx.constants.Level]) – Specifies the resting
state of the output terminal.
• initial_delay (Optional[int]) – Is the number of timebase ticks to wait before
generating the first pulse.
• low_ticks (Optional[int]) – Is the number of ticks the pulse is low.
• high_ticks (Optional[int]) – Is the number of ticks the pulse is high.
Returns Indicates the newly created channel object.
Return type nidaqmx._task_modules.channels.co_channel.COChannel
add_co_pulse_chan_time(counter,
name_to_assign_to_channel=u’‘,
units=, idle_state=, initial_delay=0.0, low_time=0.01, high_time=0.01)
Creates channel(s) to generate digital pulses defined by the amount of time the pulse is at a high state and
the amount of time the pulse is at a low state. The pulses appear on the default output terminal of the
counter unless you select a different output terminal.
Parameters
• counter (str) – Specifies the names of the counters to use to create the virtual channels.
The DAQmx physical channel constant lists all physical channels, including counters, for
devices installed in the system.
• name_to_assign_to_channel (Optional[str]) – Specifies a name to assign
to the virtual channel this function creates. If you do not specify a value for this input,
NI-DAQmx uses the physical channel name as the virtual channel name.
• units (Optional[nidaqmx.constants.TimeUnits]) – Specifies the units in
which to define pulse high and low time.

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• idle_state (Optional[nidaqmx.constants.Level]) – Specifies the resting
state of the output terminal.
• initial_delay (Optional[float]) – Is the amount of time in seconds to wait
before generating the first pulse.
• low_time (Optional[float]) – Is the amount of time the pulse is low.
• high_time (Optional[float]) – Is the amount of time the pulse is high.
Returns Indicates the newly created channel object.
Return type nidaqmx._task_modules.channels.co_channel.COChannel
all
nidaqmx._task_modules.channels.channel.Channel – Specifies a channel object that represents the entire list of virtual channels on this channel collection.
channel_names
List[str] – Specifies the entire list of virtual channels on this channel collection.
count(value) → integer – return number of occurrences of value
index(value) → integer – return first index of value.
Raises ValueError if the value is not present.
nidaqmx.task.di_channel_collection
class nidaqmx._task_modules.di_channel_collection.DIChannelCollection(task_handle)
Bases: nidaqmx._task_modules.channel_collection.ChannelCollection
Contains the collection of digital input channels for a DAQmx Task.
add_di_chan(lines, name_to_assign_to_lines=u’‘, line_grouping=)
Creates channel(s) to measure digital signals. You can group digital lines into one digital channel or
separate them into multiple digital channels. If you specify one or more entire ports in the lines input by
using port physical channel names, you cannot separate the ports into multiple channels. To separate ports
into multiple channels, use this function multiple times with a different port each time.
Parameters
• lines (str) – Specifies the names of the digital lines or ports to use to create virtual
channels. The DAQmx physical channel constant lists all lines and ports for devices installed in the system.
• name_to_assign_to_lines (Optional[str]) – Specifies a name to assign to
the virtual channel this function creates. If you do not specify a value for this input, NIDAQmx uses the physical channel name as the virtual channel name.
• line_grouping (Optional[nidaqmx.constants.LineGrouping]) – Specifies how to group digital lines into one or more virtual channels. If you specify one or
more entire ports with the lines input, you must set this input to one channel for all lines.
Returns Indicates the newly created channel object.
Return type nidaqmx._task_modules.channels.di_channel.DIChannel
all
nidaqmx._task_modules.channels.channel.Channel – Specifies a channel object that represents the entire list of virtual channels on this channel collection.

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channel_names
List[str] – Specifies the entire list of virtual channels on this channel collection.
count(value) → integer – return number of occurrences of value
index(value) → integer – return first index of value.
Raises ValueError if the value is not present.
nidaqmx.task.do_channel_collection
class nidaqmx._task_modules.do_channel_collection.DOChannelCollection(task_handle)
Bases: nidaqmx._task_modules.channel_collection.ChannelCollection
Contains the collection of digital output channels for a DAQmx Task.
add_do_chan(lines, name_to_assign_to_lines=u’‘, line_grouping=)
Creates channel(s) to generate digital signals. You can group digital lines into one digital channel or
separate them into multiple digital channels. If you specify one or more entire ports in lines input by using
port physical channel names, you cannot separate the ports into multiple channels. To separate ports into
multiple channels, use this function multiple times with a different port each time.
Parameters
• lines (str) – Specifies the names of the digital lines or ports to use to create virtual
channels. The DAQmx physical channel constant lists all lines and ports for devices installed in the system.
• name_to_assign_to_lines (Optional[str]) – Specifies a name to assign to
the virtual channel this function creates. If you do not specify a value for this input, NIDAQmx uses the physical channel name as the virtual channel name.
• line_grouping (Optional[nidaqmx.constants.LineGrouping]) – Specifies how to group digital lines into one or more virtual channels. If you specify one or
more entire ports with the lines input, you must set this input to one channel for all lines.
Returns Indicates the newly created channel object.
Return type nidaqmx._task_modules.channels.do_channel.DOChannel
all
nidaqmx._task_modules.channels.channel.Channel – Specifies a channel object that represents the entire list of virtual channels on this channel collection.
channel_names
List[str] – Specifies the entire list of virtual channels on this channel collection.
count(value) → integer – return number of occurrences of value
index(value) → integer – return first index of value.
Raises ValueError if the value is not present.

nidaqmx.task.export_signals
class nidaqmx._task_modules.export_signals.ExportSignals(task_handle)
Bases: object
Represents the exported signal configurations for a DAQmx task.
adv_cmplt_event_delay
float – Specifies the output signal delay in periods of the sample clock.
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adv_cmplt_event_output_term
str – Specifies the terminal to which to route the Advance Complete Event.
adv_cmplt_event_pulse_polarity
nidaqmx.constants.Polarity – Specifies the polarity of the exported Advance Complete Event.
adv_cmplt_event_pulse_width
float – Specifies the width of the exported Advance Complete Event pulse.
adv_trig_output_term
str – Specifies the terminal to which to route the Advance Trigger.
adv_trig_pulse_polarity
nidaqmx.constants.Polarity – Indicates the polarity of the exported Advance Trigger.
adv_trig_pulse_width
float – Specifies the width of an exported Advance Trigger pulse. Specify this value in the units you specify
with adv_trig_pulse_width_units.
adv_trig_pulse_width_units
nidaqmx.constants.DigitalWidthUnits – Specifies the units of adv_trig_pulse_width.
ai_conv_clk_output_term
str – Specifies the terminal to which to route the AI Convert Clock.
ai_conv_clk_pulse_polarity
nidaqmx.constants.Polarity – Indicates the polarity of the exported AI Convert Clock. The
polarity is fixed and independent of the active edge of the source of the AI Convert Clock.
ai_hold_cmplt_event_output_term
str – Specifies the terminal to which to route the AI Hold Complete Event.
ai_hold_cmplt_event_pulse_polarity
nidaqmx.constants.Polarity – Specifies the polarity of an exported AI Hold Complete Event
pulse.
change_detect_event_output_term
str – Specifies the terminal to which to route the Change Detection Event.
change_detect_event_pulse_polarity
nidaqmx.constants.Polarity – Specifies the polarity of an exported Change Detection Event
pulse.
ctr_out_event_output_behavior
nidaqmx.constants.ExportAction – Specifies whether the exported Counter Output Event
pulses or changes from one state to the other when the counter reaches terminal count.
ctr_out_event_output_term
str – Specifies the terminal to which to route the Counter Output Event.
ctr_out_event_pulse_polarity
nidaqmx.constants.Polarity – Specifies the polarity of the pulses at the output terminal of
the counter when ctr_out_event_output_behavior is ExportActions2.PULSE. NI-DAQmx ignores this
property if ctr_out_event_output_behavior is ExportActions2.TOGGLE.
ctr_out_event_toggle_idle_state
nidaqmx.constants.Level – Specifies the initial state of the output terminal of the counter when
ctr_out_event_output_behavior is ExportActions2.TOGGLE. The terminal enters this state when NIDAQmx commits the task.
data_active_event_lvl_active_lvl
nidaqmx.constants.Polarity – Specifies the polarity of the exported Data Active Event.

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data_active_event_output_term
str – Specifies the terminal to which to export the Data Active Event.
divided_samp_clk_timebase_output_term
str – Specifies the terminal to which to route the Divided Sample Clock Timebase.
export_signal(signal_id, output_terminal)
Routes a control signal to the terminal you specify. The output terminal can reside on the device that
generates the control signal or on a different device. You can use this function to share clocks and triggers
among multiple tasks and devices. The routes this function creates are task-based routes.
Parameters
• signal_id (nidaqmx.constants.Signal) – Is the name of the trigger, clock, or
event to export.
• output_terminal (str) – Is the destination of the exported signal. A DAQmx terminal constant lists all terminals on installed devices. You can also specify a string containing
a comma-delimited list of terminal names.
exported_10_m_hz_ref_clk_output_term
str – Specifies the terminal to which to route the 10MHz Clock.
exported_20_m_hz_timebase_output_term
str – Specifies the terminal to which to route the 20MHz Timebase.
hshk_event_delay
float – Specifies the number of seconds to delay after the Handshake Trigger deasserts before asserting the
Handshake Event.
hshk_event_interlocked_assert_on_start
bool – Specifies to assert the Handshake Event when the task starts if hshk_event_output_behavior is
ExportActions5.INTERLOCKED.
hshk_event_interlocked_asserted_lvl
nidaqmx.constants.Level – Specifies the asserted level of the exported Handshake Event if
hshk_event_output_behavior is ExportActions5.INTERLOCKED.
hshk_event_interlocked_deassert_delay
float – Specifies in seconds the amount of time to wait after the Handshake Trigger asserts before deasserting the Handshake Event if hshk_event_output_behavior is ExportActions5.INTERLOCKED.
hshk_event_output_behavior
nidaqmx.constants.ExportAction – Specifies the output behavior of the Handshake Event.
hshk_event_output_term
str – Specifies the terminal to which to route the Handshake Event.
hshk_event_pulse_polarity
nidaqmx.constants.Polarity – Specifies the polarity of the exported Handshake Event if
hshk_event_output_behavior is ExportActions5.PULSE.
hshk_event_pulse_width
float – Specifies in seconds the pulse width of
hshk_event_output_behavior is ExportActions5.PULSE.

the

exported

Handshake

Event

pause_trig_lvl_active_lvl
nidaqmx.constants.Polarity – Specifies the active level of the exported Pause Trigger.
pause_trig_output_term
str – Specifies the terminal to which to route the Pause Trigger.

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rdy_for_start_event_lvl_active_lvl
nidaqmx.constants.Polarity – Specifies the polarity of the exported Ready for Start Event.
rdy_for_start_event_output_term
str – Specifies the terminal to which to route the Ready for Start Event.
rdy_for_xfer_event_deassert_cond
nidaqmx.constants.DeassertCondition – Specifies when the ready for transfer event deasserts.
rdy_for_xfer_event_deassert_cond_custom_threshold
int – Specifies in samples the threshold below which the Ready for Transfer Event deasserts. This threshold
is an amount of space available in the onboard memory of the device. rdy_for_xfer_event_deassert_cond
must be DeassertCondition.ONBOARD_MEMORY_CUSTOM_THRESHOLD to use a custom
threshold.
rdy_for_xfer_event_lvl_active_lvl
nidaqmx.constants.Polarity – Specifies the active level of the exported Ready for Transfer
Event.
rdy_for_xfer_event_output_term
str – Specifies the terminal to which to route the Ready for Transfer Event.
ref_trig_output_term
str – Specifies the terminal to which to route the Reference Trigger.
ref_trig_pulse_polarity
nidaqmx.constants.Polarity – Specifies the polarity of the exported Reference Trigger.
samp_clk_delay_offset
float – Specifies in seconds the amount of time to offset the exported Sample clock. Refer to timing
diagrams for generation applications in the device documentation for more information about this value.
samp_clk_output_behavior
nidaqmx.constants.ExportAction – Specifies whether the exported Sample Clock issues a pulse
at the beginning of a sample or changes to a high state for the duration of the sample.
samp_clk_output_term
str – Specifies the terminal to which to route the Sample Clock.
samp_clk_pulse_polarity
nidaqmx.constants.Polarity – Specifies the polarity of the exported Sample Clock if
samp_clk_output_behavior is ExportActions3.PULSE.
samp_clk_timebase_output_term
str – Specifies the terminal to which to route the Sample Clock Timebase.
start_trig_output_term
str – Specifies the terminal to which to route the Start Trigger.
start_trig_pulse_polarity
nidaqmx.constants.Polarity – Specifies the polarity of the exported Start Trigger.
sync_pulse_event_output_term
str – Specifies the terminal to which to route the Synchronization Pulse Event.
watchdog_expired_event_output_term
str – Specifies the terminal to which to route the Watchdog Timer Expired Event.

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nidaqmx.task.in_stream
class nidaqmx._task_modules.in_stream.InStream(task)
Bases: object
Exposes an input data stream on a DAQmx task.
The input data stream be used to control reading behavior and can be used in conjunction with reader classes to
read samples from an NI-DAQmx task.
accessory_insertion_or_removal_detected
bool – Indicates if any device(s) in the task detected the insertion or removal of an accessory since the task
started. Reading this property clears the accessory change status for all channels in the task. You must read
this property before you read devs_with_inserted_or_removed_accessories. Otherwise, you will receive
an error.
auto_start
bool – Specifies if DAQmx Read automatically starts the task if you did not start the task explicitly by
using DAQmx Start. The default value is True. When DAQmx Read starts a finite acquisition task, it also
stops the task after reading the last sample.
avail_samp_per_chan
int – Indicates the number of samples available to read per channel. This value is the same for all channels
in the task.
change_detect_overflowed
bool – Indicates if samples were missed because change detection events occurred faster than the device
could handle them. Some devices detect overflows differently than others.
channels_to_read
nidaqmx._task_modules.channels.channel.Channel – Specifies a subset of channels in
the task from which to read.
common_mode_range_error_chans
List[str] – Indicates a list of names of any virtual channels in the task for which the device(s) detected
a common mode range violation. You must read common_mode_range_error_chans_exist before you
read this property. Otherwise, you will receive an error.
common_mode_range_error_chans_exist
bool – Indicates if the device(s) detected a common mode range violation for any virtual channel in the task.
Common mode range violation occurs when the voltage of either the positive terminal or negative terminal
to ground are out of range. Reading this property clears the common mode range violation status for all
channels in the task. You must read this property before you read common_mode_range_error_chans.
Otherwise, you will receive an error.
configure_logging(file_path,
logging_mode=,
group_name=u’‘,
operation=)
Configures TDMS file logging for the task.
Parameters
• file_path (str) – Specifies the path to the TDMS file to which you want to log data.
• logging_mode (Optional[nidaqmx.constants.LoggingMode]) – Specifies whether to enable logging and whether to allow reading data while logging. “log”
mode allows for the best performance. However, you cannot read data while logging if you
specify this mode. If you want to read data while logging, specify “LOG_AND_READ”
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• group_name (Optional[str]) – Specifies the name of the group to create within
the TDMS file for data from this task. If you append data to an existing file and the
specified group already exists, NI-DAQmx appends a number symbol and a number to
the group name, incrementing that number until finding a group name that does not exist.
For example, if you specify a group name of Voltage Task, and that group already exists,
NI-DAQmx assigns the group name Voltage Task #1, then Voltage Task #2. If you do not
specify a group name, NI-DAQmx uses the name of the task.
• operation (Optional[nidaqmx.constants.LoggingOperation]) – Specifies how to open the TDMS file.
curr_read_pos
float – Indicates in samples per channel the current position in the buffer.
devs_with_inserted_or_removed_accessories
List[str] – Indicates the names of any devices that detected the insertion or removal of an accessory since
the task started. You must read accessory_insertion_or_removal_detected before you read this property.
Otherwise, you will receive an error.
di_num_booleans_per_chan
int – Indicates the number of booleans per channel that NI-DAQmx returns in a sample for line-based
reads. If a channel has fewer lines than this number, the extra booleans are False.
excit_fault_chans
List[str] – Indicates a list of names of any virtual channels in the task for which the device(s) detected an
excitation fault condition. You must read excit_fault_chans_exist before you read this property. Otherwise, you will receive an error.
excit_fault_chans_exist
bool – Indicates if the device(s) detected an excitation fault condition for any virtual channel in the task.
Reading this property clears the excitation fault status for all channels in the task. You must read this
property before you read excit_fault_chans. Otherwise, you will receive an error.
input_buf_size
int – Specifies the number of samples the input buffer can hold for each channel in the task. Zero indicates
to allocate no buffer. Use a buffer size of 0 to perform a hardware-timed operation without using a buffer.
Setting this property overrides the automatic input buffer allocation that NI- DAQmx performs.
input_onbrd_buf_size
int – Indicates in samples per channel the size of the onboard input buffer of the device.
logging_file_path
str – Specifies the path to the TDMS file to which you want to log data. If the file path is changed while
the task is running, this takes effect on the next sample interval (if Logging.SampsPerFile has been set) or
when DAQmx Start New File is called. New file paths can be specified by ending with “” or “/”. Files
created after specifying a new file path retain the same name and numbering sequence.
logging_file_preallocation_size
long – Specifies a size in samples to be used to pre-allocate space on disk. Pre-allocation can improve file
I/O performance, especially in situations where multiple files are being written to disk. For finite tasks,
the default behavior is to pre-allocate the file based on the number of samples you configure the task to
acquire.
logging_file_write_size
int – Specifies the size, in samples, in which data will be written to disk. The size must be evenly divisible
by the volume sector size, in bytes.
logging_mode
nidaqmx.constants.LoggingMode – Specifies whether to enable logging and whether to allow
reading data while logging. Log mode allows for the best performance. However, you cannot read data

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while logging if you specify this mode. If you want to read data while logging, specify Log and Read
mode.
logging_pause
bool – Specifies whether logging is paused while a task is executing. If logging_mode is set to Log and
Read mode, this value is taken into consideration on the next call to DAQmx Read, where data is written
to disk. If logging_mode is set to Log Only mode, this value is taken into consideration the next time that
data is written to disk. A new TDMS group is written when logging is resumed from a paused state.
logging_samps_per_file
long – Specifies how many samples to write to each file. When the file reaches the number of samples
specified, a new file is created with the naming convention of _####.tdms, where #### starts
at 0001 and increments automatically with each new file. For example, if the file specified is C:data.tdms,
the next file name used is C:data_0001.tdms. To disable file spanning behavior, set this attribute to 0.
If logging_file_path is changed while this attribute is set, the new file path takes effect on the next file
created.
logging_tdms_group_name
str – Specifies the name of the group to create within the TDMS file for data from this task. If you append
data to an existing file and the specified group already exists, NI- DAQmx appends a number symbol and
a number to the group name, incrementing that number until finding a group name that does not exist. For
example, if you specify a group name of Voltage Task, and that group already exists, NI- DAQmx assigns
the group name Voltage Task #1, then Voltage Task #2.
logging_tdms_operation
nidaqmx.constants.LoggingOperation – Specifies how to open the TDMS file.
num_chans
int – Indicates the number of channels that DAQmx Read reads from the task. This value is the number of
channels in the task or the number of channels you specify with channels_to_read.
offset
int – Specifies an offset in samples per channel at which to begin a read operation. This offset is relative
to the location you specify with relative_to.
open_chans
List[str] – Indicates a list of names of any open virtual channels. You must read open_chans_exist before
you read this property. Otherwise you will receive an error.
open_chans_details
List[str] – Indicates a list of details of any open virtual channels. You must read open_chans_exist before
you read this property. Otherwise you will receive an error.
open_chans_exist
bool – Indicates if the device or devices detected an open channel condition in any virtual channel in the
task. Reading this property clears the open channel status for all channels in this task. You must read this
property before you read open_chans. Otherwise, you will receive an error.
open_current_loop_chans
List[str] – Indicates a list of names of any virtual channels in the task for which the device(s) detected
an open current loop. You must read open_current_loop_chans_exist before you read this property.
Otherwise, you will receive an error.
open_current_loop_chans_exist
bool – Indicates if the device(s) detected an open current loop for any virtual channel in the task. Reading
this property clears the open current loop status for all channels in the task. You must read this property
before you read open_current_loop_chans. Otherwise, you will receive an error.
open_thrmcpl_chans
List[str] – Indicates a list of names of any virtual channels in the task for which the device(s) detected an

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open thermcouple. You must read open_thrmcpl_chans_exist before you read this property. Otherwise,
you will receive an error.
open_thrmcpl_chans_exist
bool – Indicates if the device(s) detected an open thermocouple connected to any virtual channel in the
task. Reading this property clears the open thermocouple status for all channels in the task. You must read
this property before you read open_thrmcpl_chans. Otherwise, you will receive an error.
over_write
nidaqmx.constants.OverwriteMode – Specifies whether to overwrite samples in the buffer that
you have not yet read.
overcurrent_chans
List[str] – Indicates a list of names of any virtual channels in the task for which the device(s) detected an
overcurrent condition. You must read overcurrent_chans_exist before you read this property. Otherwise,
you will receive an error. On some devices, you must restart the task for all overcurrent channels to recover.
overcurrent_chans_exist
bool – Indicates if the device(s) detected an overcurrent condition for any virtual channel in the task.
Reading this property clears the overcurrent status for all channels in the task. You must read this property
before you read overcurrent_chans. Otherwise, you will receive an error.
overloaded_chans
List[str] – Indicates a list of names of any overloaded virtual channels in the task. You must read overloaded_chans_exist before you read this property. Otherwise, you will receive an error.
overloaded_chans_exist
bool – Indicates if the device(s) detected an overload in any virtual channel in the task. Reading this
property clears the overload status for all channels in the task. You must read this property before you read
overloaded_chans. Otherwise, you will receive an error.
overtemperature_chans
List[str] – Indicates a list of names of any overtemperature virtual channels. You must read overtemperature_chans_exist before you read this property. Otherwise, you will receive an error.
overtemperature_chans_exist
bool – Indicates if the device(s) detected an overtemperature condition in any virtual channel in the task.
Reading this property clears the overtemperature status for all channels in the task. You must read this
property before you read overtemperature_chans. Otherwise, you will receive an error.
raw_data_width
int – Indicates in bytes the size of a raw sample from the task.
read(number_of_samples_per_channel=-1)
Reads raw samples from the task or virtual channels you specify.
Raw samples constitute the internal representation of samples in a device, read directly from the device
or buffer without scaling or reordering. The native format of a device can be an 8-, 16-, or 32-bit integer,
signed or unsigned.
NI-DAQmx does not separate raw data into channels. It returns data in an interleaved or non-interleaved
1D array, depending on the raw ordering of the device. Refer to your device documentation for more
information.
This method determines a NumPy array of appropriate size and data type to create and return based on
your device specifications.
Use the “timeout” property on the stream to specify the amount of time in seconds to wait for samples
to become available. If the time elapses, the method returns an error and any samples read before the
timeout elapsed. The default timeout is 10 seconds. If you set timeout to nidaqmx.WAIT_INFINITELY,

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the method waits indefinitely. If you set timeout to 0, the method tries once to read the requested samples
and returns an error if it is unable to.
Parameters number_of_samples_per_channel (int) – Specifies the number of samples to read.
If you set this input to nidaqmx.READ_ALL_AVAILABLE, NI-DAQmx determines how
many samples to read based on if the task acquires samples continuously or acquires a finite
number of samples.
If the task acquires samples continuously and you set this input to
nidaqmx.READ_ALL_AVAILABLE, this method reads all the samples currently available
in the buffer.
If the task acquires a finite number of samples and you set this input to
nidaqmx.READ_ALL_AVAILABLE, the method waits for the task to acquire all requested
samples, then reads those samples. If you set the “read_all_avail_samp” property to TRUE,
the method reads the samples currently available in the buffer and does not wait for the task
to acquire all requested samples.
Returns The samples requested in the form of a 1D NumPy array. This method determines a
NumPy array of appropriate size and data type to create and return based on your device
specifications.
Return type numpy.ndarray
read_all_avail_samp
bool – Specifies whether subsequent read operations read all samples currently available in the buffer or
wait for the buffer to become full before reading. NI-DAQmx uses this setting for finite acquisitions and
only when the number of samples to read is -1. For continuous acquisitions when the number of samples
to read is -1, a read operation always reads all samples currently available in the buffer.
readall()
Reads all available raw samples from the task or virtual channels you specify.
NI-DAQmx determines how many samples to read based on if the task acquires samples continuously or
acquires a finite number of samples.
If the task acquires samples continuously, this method reads all the samples currently available in the
buffer.
If the task acquires a finite number of samples, the method waits for the task to acquire all requested
samples, then reads those samples. If you set the “read_all_avail_samp” property to TRUE, the method
reads the samples currently available in the buffer and does not wait for the task to acquire all requested
samples.
Raw samples constitute the internal representation of samples in a device, read directly from the device
or buffer without scaling or reordering. The native format of a device can be an 8-, 16-, or 32-bit integer,
signed or unsigned.
NI-DAQmx does not separate raw data into channels. It returns data in an interleaved or non-interleaved
1D array, depending on the raw ordering of the device. Refer to your device documentation for more
information.
This method determines a NumPy array of appropriate size and data type to create and return based on
your device specifications.
Use the “timeout” property on the stream to specify the amount of time in seconds to wait for samples
to become available. If the time elapses, the method returns an error and any samples read before the
timeout elapsed. The default timeout is 10 seconds. If you set timeout to nidaqmx.WAIT_INFINITELY,

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the method waits indefinitely. If you set timeout to 0, the method tries once to read the requested samples
and returns an error if it is unable to.
Returns The samples requested in the form of a 1D NumPy array. This method determines a
NumPy array of appropriate size and data type to create and return based on your device
specifications.
Return type numpy.ndarray
readinto(numpy_array)
Reads raw samples from the task or virtual channels you specify into numpy_array.
The object numpy_array should be a pre-allocated, writable 1D numpy array.
The number of samples per channel to read is determined using the following equation:
number_of_samples_per_channel = math.floor(
numpy_array_size_in_bytes / ( number_of_channels_to_read * raw_sample_size_in_bytes))
Raw samples constitute the internal representation of samples in a device, read directly from the device
or buffer without scaling or reordering. The native format of a device can be an 8-, 16-, or 32-bit integer,
signed or unsigned.
If you use a different integer size than the native format of the device, one integer can contain multiple
samples or one sample can stretch across multiple integers. For example, if you use 32-bit integers, but the
device uses 8-bit samples, one integer contains up to four samples. If you use 8-bit integers, but the device
uses 16-bit samples, a sample might require two integers. This behavior varies from device to device.
Refer to your device documentation for more information.
NI-DAQmx does not separate raw data into channels. It returns data in an interleaved or non-interleaved
1D array, depending on the raw ordering of the device. Refer to your device documentation for more
information.
Use the “timeout” property on the stream to specify the amount of time in seconds to wait for samples to
become available. If the time elapses, the method returns an error and any samples read before the timeout
elapsed. The default timeout is 10 seconds. If you set timeout to -1, the method waits indefinitely. If you
set timeout to 0, the method tries once to read the requested samples and returns an error if it is unable to.
Parameters numpy_array – Specifies the 1D NumPy array object into which the samples
requested are read.
Returns Indicates the total number of samples read.
Return type int
relative_to
nidaqmx.constants.ReadRelativeTo – Specifies the point in the buffer at which to begin a read operation. If you also specify an offset with offset, the read operation begins at
that offset relative to the point you select with this property. The default value is ReadRelativeTo.CURRENT_READ_POSITION unless you configure a Reference Trigger for the task. If you
configure a Reference Trigger, the default value is ReadRelativeTo.FIRST_PRETRIGGER_SAMPLE.
sleep_time
float – Specifies in seconds the amount of time to sleep after checking for available samples if wait_mode
is WaitMode.SLEEP.
start_new_file(file_path)
Starts a new TDMS file the next time data is written to disk.
Parameters file_path (str) – Specifies the path to the TDMS file to which you want to log
data.

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timeout
float – Specifies the amount of time in seconds to wait for samples to become available. If the time elapses,
the read method returns an error and any samples read before the timeout elapsed. The default timeout is
10 seconds. If you set timeout to nidaqmx.WAIT_INFINITELY, the read method waits indefinitely. If you
set timeout to 0, the read method tries once to read the requested samples and returns an error if it is unable
to.
total_samp_per_chan_acquired
float – Indicates the total number of samples acquired by each channel. NI-DAQmx returns a single value
because this value is the same for all channels. For retriggered acquisitions, this value is the cumulative
number of samples across all retriggered acquisitions.
wait_mode
nidaqmx.constants.WaitMode – Specifies how DAQmx Read waits for samples to become available.

nidaqmx.task.out_stream
class nidaqmx._task_modules.out_stream.OutStream(task)
Bases: object
Exposes an output data stream on a DAQmx task.
The output data stream be used to control writing behavior and can be used in conjunction with writer classes to
write samples to an NI-DAQmx task.
accessory_insertion_or_removal_detected
bool – Indicates if any devices in the task detected the insertion or removal of an accessory since the task
started. Reading this property clears the accessory change status for all channels in the task. You must read
this property before you read devs_with_inserted_or_removed_accessories. Otherwise, you will receive
an error.
auto_start
bool – Specifies if the “write” method automatically starts the stream’s owning task if you did not explicitly
start it with the DAQmx Start Task method.
curr_write_pos
float – Indicates the position in the buffer of the next sample to generate. This value is identical for all
channels in the task.
devs_with_inserted_or_removed_accessories
List[str] – Indicates the names of any devices that detected the insertion or removal of an accessory since
the task started. You must read accessory_insertion_or_removal_detected before you read this property.
Otherwise, you will receive an error.
do_num_booleans_per_chan
int – Indicates the number of Boolean values expected per channel in a sample for line-based writes. This
property is determined by the channel in the task with the most digital lines. If a channel has fewer lines
than this number, NI- DAQmx ignores the extra Boolean values.
external_overvoltage_chans
List[str] – Indicates a list of names of any virtual channels in the task for which an External Overvoltage
condition has been detected. You must read External OvervoltageChansExist before you read this property.
Otherwise, you will receive an error.
external_overvoltage_chans_exist
bool – Indicates if the device(s) detected an External Overvoltage condition for any channel in the task.
Reading this property clears the External Overvoltage status for all channels in the task. You must read
this property before you read External OvervoltageChans. Otherwise, you will receive an error.
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num_chans
int – Indicates the number of channels that DAQmx Write writes to the task. This value is the number of
channels in the task.
offset
int – Specifies in samples per channel an offset at which a write operation begins. This offset is relative to
the location you specify with relative_to.
open_current_loop_chans
List[str] – Indicates a list of names of any virtual channels in the task for which the device(s) detected
an open current loop. You must read open_current_loop_chans_exist before you read this property.
Otherwise, you will receive an error.
open_current_loop_chans_exist
bool – Indicates if the device(s) detected an open current loop for any channel in the task. Reading this
property clears the open current loop status for all channels in the task. You must read this property before
you read open_current_loop_chans. Otherwise, you will receive an error.
output_buf_size
int – Specifies the number of samples the output buffer can hold for each channel in the task. Zero indicates
to allocate no buffer. Use a buffer size of 0 to perform a hardware-timed operation without using a buffer.
Setting this property overrides the automatic output buffer allocation that NI- DAQmx performs.
output_onbrd_buf_size
int – Specifies in samples per channel the size of the onboard output buffer of the device.
overcurrent_chans
List[str] – Indicates a list of names of any virtual channels in the task for which an overcurrent condition
has been detected. You must read overcurrent_chans_exist before you read this property. Otherwise, you
will receive an error.
overcurrent_chans_exist
bool – Indicates if the device(s) detected an overcurrent condition for any channel in the task. Reading this
property clears the overcurrent status for all channels in the task. You must read this property before you
read overcurrent_chans. Otherwise, you will receive an error.
overloaded_chans
List[str] – Indicates a list of names of any overloaded virtual channels in the task. You must read overloaded_chans_exist before you read this property. Otherwise, you will receive an error.
overloaded_chans_exist
bool – Indicates if the device(s) detected an overload in any virtual channel in the task. Reading this
property clears the overload status for all channels in the task. You must read this property before you read
overloaded_chans. Otherwise, you will receive an error.
overtemperature_chans
List[str] – Indicates a list of names of any overtemperature virtual channels. You must read overtemperature_chans_exist before you read this property. Otherwise, you will receive an error. The list of names
may be empty if the device cannot determine the source of the overtemperature.
overtemperature_chans_exist
bool – Indicates if the device(s) detected an overtemperature condition in any virtual channel in the task.
Reading this property clears the overtemperature status for all channels in the task. You must read this
property before you read overtemperature_chans. Otherwise, you will receive an error.
power_supply_fault_chans
List[str] – Indicates a list of names of any virtual channels in the task that have a power supply fault. You
must read power_supply_fault_chans_exist before you read this property. Otherwise, you will receive
an error.

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power_supply_fault_chans_exist
bool – Indicates if the device(s) detected a power supply fault for any channel in the task. Reading this
property clears the power supply fault status for all channels in the task. You must read this property before
you read power_supply_fault_chans. Otherwise, you will receive an error.
raw_data_width
int – Indicates in bytes the required size of a raw sample to write to the task.
regen_mode
nidaqmx.constants.RegenerationMode – Specifies whether to allow NI-DAQmx to generate
the same data multiple times.
relative_to
nidaqmx.constants.WriteRelativeTo – Specifies the point in the buffer at which to write data.
If you also specify an offset with offset, the write operation begins at that offset relative to this point you
select with this property.
sleep_time
float – Specifies in seconds the amount of time to sleep after checking for available buffer space if
wait_mode is WaitMode2.SLEEP.
space_avail
int – Indicates in samples per channel the amount of available space in the buffer.
timeout
float – Specifies the amount of time in seconds to wait for the write method to write all samples. NIDAQmx performs a timeout check only if the write method must wait before it writes data. The write
method returns an error if the time elapses. The default timeout is 10 seconds. If you set “timeout”
to nidaqmx.WAIT_INFINITELY, the write method waits indefinitely. If you set timeout to 0, the write
method tries once to write the submitted samples. If the write method could not write all the submitted
samples, it returns an error and the number of samples successfully written in the number of samples
written per channel output.
total_samp_per_chan_generated
float – Indicates the total number of samples generated by each channel in the task. This value is identical
for all channels in the task.
wait_mode
nidaqmx.constants.WaitMode – Specifies how DAQmx Write waits for space to become available
in the buffer.
write(numpy_array)
Writes raw samples to the task or virtual channels you specify.
The number of samples per channel to write is determined using the following equation:
number_of_samples_per_channel = math.floor(
numpy_array_size_in_bytes / ( number_of_channels_to_write * raw_sample_size_in_bytes))
Raw samples constitute the internal representation of samples in a device, read directly from the device
or buffer without scaling or reordering. The native format of a device can be an 8-, 16-, or 32-bit integer,
signed or unsigned.
If you use a different integer size than the native format of the device, one integer can contain multiple
samples or one sample can stretch across multiple integers. For example, if you use 32-bit integers, but the
device uses 8-bit samples, one integer contains up to four samples. If you use 8-bit integers, but the device
uses 16-bit samples, a sample might require two integers. This behavior varies from device to device.
Refer to your device documentation for more information.

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NI-DAQmx does not separate raw data into channels. It accepts data in an interleaved or non-interleaved
1D array, depending on the raw ordering of the device. Refer to your device documentation for more
information.
If the task uses on-demand timing, this method returns only after the device generates all samples. Ondemand is the default timing type if you do not use the timing property on the task to configure a sample
timing type. If the task uses any timing type other than on-demand, this method returns immediately and
does not wait for the device to generate all samples. Your application must determine if the task is done to
ensure that the device generated all samples.
Use the “auto_start” property on the stream to specify if this method automatically starts the stream’s
owning task if you did not explicitly start it with the DAQmx Start Task method.
Use the “timeout” property on the stream to specify the amount of time in seconds to wait for the method
to write all samples. NI-DAQmx performs a timeout check only if the method must wait before it writes
data. This method returns an error if the time elapses. The default timeout is 10 seconds. If you set timeout
to nidaqmx.WAIT_INFINITELY, the method waits indefinitely. If you set timeout to 0, the method tries
once to write the submitted samples. If the method could not write all the submitted samples, it returns an
error and the number of samples successfully written.
Parameters numpy_array (numpy.ndarray) – Specifies a 1D NumPy array that contains
the raw samples to write to the task.
Returns Specifies the actual number of samples per channel successfully written to the buffer.
Return type int

nidaqmx.task.timing
class nidaqmx._task_modules.timing.Timing(task_handle)
Bases: object
Represents the timing configurations for a DAQmx task.
ai_conv_active_edge
nidaqmx.constants.Edge – Specifies on which edge of the clock pulse an analog-to-digital conversion takes place.
ai_conv_dig_fltr_enable
bool – Specifies whether to apply a digital filter to the AI Convert Clock.
ai_conv_dig_fltr_min_pulse_width
float – Specifies in seconds the minimum pulse width the filter recognizes.
ai_conv_dig_fltr_timebase_rate
float – Specifies in hertz the rate of the digital filter timebase. NI-DAQmx uses this value to compute
settings for the filter.
ai_conv_dig_fltr_timebase_src
str – Specifies the terminal of the signal to use as the timebase of the digital filter.
ai_conv_dig_sync_enable
bool – Specifies whether to synchronize recognition of transitions in the signal to the internal timebase of
the device.
ai_conv_max_rate
float – Indicates the maximum convert rate supported by the task, given the current devices and channel
count.

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ai_conv_rate
float – Specifies in Hertz the rate at which to clock the analog- to-digital converter. This clock is specific
to the analog input section of multiplexed devices.
ai_conv_src
str – Specifies the terminal of the signal to use as the AI Convert Clock.
ai_conv_timebase_div
int – Specifies the number of AI Convert Clock Timebase pulses needed to produce a single AI Convert
Clock pulse.
ai_conv_timebase_src
nidaqmx.constants.MIOAIConvertTimebaseSource – Specifies the terminal of the signal to
use as the AI Convert Clock Timebase.
cfg_burst_handshaking_timing_export_clock(sample_clk_rate, sample_clk_outp_term,
sample_mode=, samps_per_chan=1000, sample_clk_pulse_polarity=,
pause_when=, ready_event_active_level=)
Configures when the DAQ device transfers data to a peripheral device, using the onboard Sample Clock
of the DAQ device to control burst handshake timing and exporting that clock for use by the peripheral
device.
Parameters
• sample_clk_rate (float) – Specifies in hertz the rate of the Sample Clock.
• sample_clk_outp_term (str) – Specifies the terminal to which to export the Sample Clock.
• sample_mode (Optional[nidaqmx.constants.AcquisitionType]) –
Specifies if the task acquires or generates samples continuously or if it acquires or
generates a finite number of samples.
• samps_per_chan (Optional[long]) – Specifies the number of samples to acquire
or generate for each channel in the task if sample_mode is FINITE_SAMPLES. If sample_mode is CONTINUOUS_SAMPLES, NI-DAQmx uses this value to determine the
buffer size. This function returns an error if the specified value is negative.
• sample_clk_pulse_polarity
(Optional[nidaqmx.constants.
Polarity]) – Specifies the polarity of the exported Sample Clock.
• pause_when (Optional[nidaqmx.constants.Level]) – Specifies whether
the task pauses while the trigger signal is high or low.
• ready_event_active_level
(Optional[nidaqmx.constants.
Polarity]) – Specifies the polarity of the Ready for Transfer Event.
cfg_burst_handshaking_timing_import_clock(sample_clk_rate, sample_clk_src, sample_mode=, samps_per_chan=1000, sample_clk_active_edge=,
pause_when=, ready_event_active_level=)
Configures when the DAQ device transfers data to a peripheral device, using an imported sample clock to
control burst handshake timing.

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Parameters
• sample_clk_rate (float) – Specifies in hertz the rate of the Sample Clock.
• sample_clk_src (str) – Specifies the source terminal of the Sample Clock. Leave
this input unspecified to use the default onboard clock of the device.
• sample_mode (Optional[nidaqmx.constants.AcquisitionType]) –
Specifies if the task acquires or generates samples continuously or if it acquires or
generates a finite number of samples.
• samps_per_chan (Optional[long]) – Specifies the number of samples to acquire
or generate for each channel in the task if sample_mode is FINITE_SAMPLES. If sample_mode is CONTINUOUS_SAMPLES, NI-DAQmx uses this value to determine the
buffer size. This function returns an error if the specified value is negative.
• sample_clk_active_edge (Optional[nidaqmx.constants.Edge])
Specifies on which edges of Sample Clock pulses to acquire or generate samples.

–

• pause_when (Optional[nidaqmx.constants.Level]) – Specifies whether
the task pauses while the trigger signal is high or low.
• ready_event_active_level
(Optional[nidaqmx.constants.
Polarity]) – Specifies the polarity of the Ready for Transfer Event.
cfg_change_detection_timing(rising_edge_chan=u’‘,
falling_edge_chan=u’‘,
sample_mode=,
samps_per_chan=1000)
Configures the task to acquire samples on the rising and/or falling edges of the lines or ports you specify.
To detect both rising and falling edges on a line or port, specify the name of that line or port to both
rising_edge_chan and falling_edge_chan.
Parameters
• rising_edge_chan (Optional[str]) – Specifies the names of the digital lines or
ports on which to detect rising edges. The DAQmx physical channel constant lists all lines
and ports for devices installed in your system.
• falling_edge_chan (Optional[str]) – Specifies the names of the digital lines
or ports on which to detect falling edges. The DAQmx physical channel constant lists all
lines and ports for devices installed in your system.
• sample_mode (Optional[nidaqmx.constants.AcquisitionType]) –
Specifies if the task acquires samples continuously or if it acquires a finite number of
samples.
• samps_per_chan (Optional[long]) – Specifies the number of samples to acquire
from each channel in the task if sample_mode is FINITE_SAMPLES. This function
returns an error if the specified value is negative.
cfg_handshaking_timing(sample_mode=,
samps_per_chan=1000)
Determines the number of digital samples to acquire or generate using digital handshaking between the
device and a peripheral device.
Parameters
• sample_mode (Optional[nidaqmx.constants.AcquisitionType]) –
Specifies if the task acquires or generates samples continuously or if it acquires or
generates a finite number of samples.

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• samps_per_chan (Optional[long]) – Specifies the number of samples to acquire
or generate for each channel in the task if sample_mode is FINITE_SAMPLES. If sample_mode is CONTINUOUS_SAMPLES, NI-DAQmx uses this value to determine the
buffer size. This function returns an error if the specified value is negative.
cfg_implicit_timing(sample_mode=,
samps_per_chan=1000)
Sets only the number of samples to acquire or generate without specifying timing. Typically, you should
use this instance when the task does not require sample timing, such as tasks that use counters for buffered
frequency measurement, buffered period measurement, or pulse train generation. For finite counter output
tasks, samps_per_chan is the number of pulses to generate.
Parameters
• sample_mode (Optional[nidaqmx.constants.AcquisitionType]) –
Specifies if the task acquires or generates samples continuously or if it acquires or
generates a finite number of samples.
• samps_per_chan (Optional[long]) – Specifies the number of samples to acquire
or generate for each channel in the task if sample_mode is FINITE_SAMPLES. If sample_mode is CONTINUOUS_SAMPLES, NI-DAQmx uses this value to determine the
buffer size. This function returns an error if the specified value is negative.
cfg_pipelined_samp_clk_timing(rate, source=u’‘, active_edge=,
sample_mode=,
samps_per_chan=1000)
“Sets the source of the Sample Clock, the rate of the Sample Clock, and the number of samples
to acquire or generate. The device acquires or generates samples on each Sample Clock edge,
but it does not respond to certain triggers until a few Sample Clock edges later. Pipelining allows
higher data transfer rates at the cost of increased trigger response latency. Refer to the device
documentation for information about which triggers pipelining affects.
This timing type allows handshaking using the Pause trigger and either the Ready for Transfer event or
the Data Active event. Refer to the device documentation for more information.
This timing type is supported only by the NI 6536 and NI 6537.”
Args:
rate (float): Specifies the sampling rate in samples per channel per second. If you use an external source for the Sample Clock, set this input to the maximum expected rate of that clock.
source (Optional[str]): Specifies the source terminal of the Sample Clock. Leave this input
unspecified to use the default onboard clock of the device.
active_edge (Optional[nidaqmx.constants.Edge]): Specifies on which edges of Sample Clock
pulses to acquire or generate samples.
sample_mode (Optional[nidaqmx.constants.AcquisitionType]): Specifies if the task acquires
or generates samples continuously or if it acquires or generates a finite number of samples.
samps_per_chan (Optional[long]): Specifies the number of samples to acquire or generate
for each channel in the task if sample_mode is FINITE_SAMPLES. If sample_mode is
CONTINUOUS_SAMPLES, NI-DAQmx uses this value to determine the buffer size. This
function returns an error if the specified value is negative.
cfg_samp_clk_timing(rate,
source=u’‘,
active_edge=,
sample_mode=, samps_per_chan=1000)
Sets the source of the Sample Clock, the rate of the Sample Clock, and the number of samples to acquire
or generate.

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Parameters
• rate (float) – Specifies the sampling rate in samples per channel per second. If you
use an external source for the Sample Clock, set this input to the maximum expected rate
of that clock.
• source (Optional[str]) – Specifies the source terminal of the Sample Clock. Leave
this input unspecified to use the default onboard clock of the device.
• active_edge (Optional[nidaqmx.constants.Edge]) – Specifies on which
edges of Sample Clock pulses to acquire or generate samples.
• sample_mode (Optional[nidaqmx.constants.AcquisitionType]) –
Specifies if the task acquires or generates samples continuously or if it acquires or
generates a finite number of samples.
• samps_per_chan (Optional[long]) – Specifies the number of samples to acquire
or generate for each channel in the task if sample_mode is FINITE_SAMPLES. If sample_mode is CONTINUOUS_SAMPLES, NI-DAQmx uses this value to determine the
buffer size. This function returns an error if the specified value is negative.
change_detect_di_falling_edge_physical_chans
nidaqmx.system.physical_channel.PhysicalChannel – Specifies the names of the digital
lines or ports on which to detect falling edges. The lines or ports must be used by virtual channels in the
task. You also can specify a string that contains a list or range of digital lines or ports.
change_detect_di_rising_edge_physical_chans
nidaqmx.system.physical_channel.PhysicalChannel – Specifies the names of the digital
lines or ports on which to detect rising edges. The lines or ports must be used by virtual channels in the
task. You also can specify a string that contains a list or range of digital lines or ports.
change_detect_di_tristate
bool – Specifies whether to tristate lines specified with change_detect_di_rising_edge_physical_chans
and change_detect_di_falling_edge_physical_chans that are not in a virtual channel in the task. If you
set this property to True, NI-DAQmx tristates rising/falling edge lines that are not in a virtual channel in
the task. If you set this property to False, NI-DAQmx does not modify the configuration of rising/falling
edge lines that are not in a virtual channel in the task, even if the lines were previously tristated. Set this
property to False to detect changes on lines in other tasks or to detect changes on output-only lines.
delay_from_samp_clk_delay
float – Specifies the amount of time to wait after receiving a Sample Clock edge before beginning to
acquire the sample. This value is in the units you specify with delay_from_samp_clk_delay_units.
delay_from_samp_clk_delay_units
nidaqmx.constants.DigitalWidthUnits
lay_from_samp_clk_delay.

–

Specifies

the

units

de-

hshk_delay_after_xfer
float – Specifies the number of seconds to wait after a handshake cycle before starting a new handshake
cycle.
hshk_sample_input_data_when
nidaqmx.constants.SampleInputDataWhen – Specifies on which edge of the Handshake Trigger an input task latches the data from the peripheral device.
hshk_start_cond
nidaqmx.constants.HandshakeStartCondition – Specifies the point in the handshake cycle
that the device is in when the task starts.
implicit_underflow_behavior

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nidaqmx.constants.UnderflowBehavior – Specifies the action to take when the onboard memory of the device becomes empty.
master_timebase_rate
float – Specifies the rate of the Master Timebase.
master_timebase_src
str – Specifies the terminal of the signal to use as the Master Timebase. On an E Series device, you can
choose only between the onboard 20MHz Timebase or the RTSI7 terminal.
ref_clk_rate
float – Specifies the frequency of the Reference Clock.
ref_clk_src
str – Specifies the terminal of the signal to use as the Reference Clock.
samp_clk_active_edge
nidaqmx.constants.Edge – Specifies on which edge of a clock pulse sampling takes place. This
property is useful primarily when the signal you use as the Sample Clock is not a periodic clock.
samp_clk_dig_fltr_enable
bool – Specifies whether to apply the pulse width filter to the signal.
samp_clk_dig_fltr_min_pulse_width
float – Specifies in seconds the minimum pulse width the filter recognizes.
samp_clk_dig_fltr_timebase_rate
float – Specifies in hertz the rate of the pulse width filter timebase. NI-DAQmx uses this value to compute
settings for the filter.
samp_clk_dig_fltr_timebase_src
str – Specifies the input terminal of the signal to use as the timebase of the pulse width filter.
samp_clk_dig_sync_enable
bool – Specifies whether to synchronize recognition of transitions in the signal to the internal timebase of
the device.
samp_clk_max_rate
float – Indicates the maximum Sample Clock rate supported by the task, based on other timing settings.
For output tasks, the maximum Sample Clock rate is the maximum rate of the DAC. For input tasks,
NI-DAQmx calculates the maximum sampling rate differently for multiplexed devices than simultaneous
sampling devices.
samp_clk_overrun_behavior
nidaqmx.constants.OverflowBehavior – Specifies the action to take if Sample Clock edges
occur faster than the device can handle them.
samp_clk_rate
float – Specifies the sampling rate in samples per channel per second. If you use an external source for the
Sample Clock, set this input to the maximum expected rate of that clock.
samp_clk_src
str – Specifies the terminal of the signal to use as the Sample Clock.
samp_clk_term
str – Indicates the name of the internal Sample Clock terminal for the task. This property does not return
the name of the Sample Clock source terminal specified with samp_clk_src.
samp_clk_timebase_active_edge
nidaqmx.constants.Edge – Specifies on which edge to recognize a Sample Clock Timebase pulse.
This property is useful primarily when the signal you use as the Sample Clock Timebase is not a periodic
clock.

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samp_clk_timebase_div
int – Specifies the number of Sample Clock Timebase pulses needed to produce a single Sample Clock
pulse.
samp_clk_timebase_master_timebase_div
int – Specifies the number of pulses of the Master Timebase needed to produce a single pulse of the Sample
Clock Timebase.
samp_clk_timebase_rate
float – Specifies the rate of the Sample Clock Timebase. Some applications require that you specify a rate
when you use any signal other than the onboard Sample Clock Timebase. NI- DAQmx requires this rate
to calculate other timing parameters.
samp_clk_timebase_src
str – Specifies the terminal of the signal to use as the Sample Clock Timebase.
samp_clk_timebase_term
str – Indicates the name of the internal Sample Clock Timebase terminal for the task. This
property does not return the name of the Sample Clock Timebase source terminal specified with
samp_clk_timebase_src.
samp_clk_underflow_behavior
nidaqmx.constants.UnderflowBehavior – Specifies the action to take when the onboard memory of the device becomes empty. In either case, the sample clock does not stop.
samp_clk_write_wfm_use_initial_wfm_dt
bool – Specifies that the value of samp_clk_rate will be determined by the dt component of the initial
DAQmx Write waveform input for Output tasks.
samp_quant_samp_mode
nidaqmx.constants.AcquisitionType – Specifies if a task acquires or generates a finite number
of samples or if it continuously acquires or generates samples.
samp_quant_samp_per_chan
float – Specifies the number of samples to acquire or generate for each channel if
samp_quant_samp_mode is AcquisitionType.FINITE. If samp_quant_samp_mode is AcquisitionType.CONTINUOUS, NI-DAQmx uses this value to determine the buffer size.
samp_timing_engine
int – Specifies which timing engine to use for the task.
samp_timing_type
nidaqmx.constants.SampleTimingType – Specifies the type of sample timing to use for the
task.
simultaneous_ao_enable
bool – Specifies whether to update all channels in the task simultaneously, rather than updating channels
independently when you write a sample to that channel.
sync_clk_interval
int – Specifies the interval, in Sample Clock periods, between each internal Synchronization Clock pulse.
NI-DAQmx uses this pulse for synchronization of triggers between multiple devices at different rates.
Refer to device documentation for information about how to calculate this value.
sync_pulse_min_delay_to_start
float – Specifies in seconds the amount of time that elapses after the master device issues the synchronization pulse before the task starts.
sync_pulse_reset_delay
float – Specifies in seconds the amount of time to wait after the Synchronization Pulse before resetting the
ADCs or DACs on the device. When synchronizing devices, query sync_pulse_reset_time on all devices

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and note the largest reset time. Then, for each device, subtract the reset time from the largest reset time
and set this property to the resulting value.
sync_pulse_reset_time
float – Indicates in seconds the amount of time required for the ADCs or DACs on the device to reset.
When synchronizing devices, query this property on all devices and note the largest reset time. Then, for
each device, subtract the value of this property from the largest reset time and set sync_pulse_reset_delay
to the resulting value.
sync_pulse_src
str – Specifies the terminal of the signal to use as the synchronization pulse. The synchronization pulse
resets the clock dividers and the ADCs/DACs on the device.
sync_pulse_sync_time
float – Indicates in seconds the delay required to reset the ADCs/DACs after the device receives the synchronization pulse.
sync_pulse_term
str – Indicates the name of the internal Synchronization Pulse terminal for the task. This property does not
return the name of the source terminal.

nidaqmx.task.triggers
class nidaqmx._task_modules.triggers.Triggers(task_handle)
Bases: object
Represents the trigger configurations for a DAQmx task.
arm_start_trigger
nidaqmx._task_modules.triggering.arm_start_trigger.ArmStartTrigger
Gets the arm start trigger configurations for the task.

–

handshake_trigger
nidaqmx._task_modules.triggering.handshake_trigger.HandshakeTrigger
Gets the handshake trigger configurations for the task.

–

pause_trigger
nidaqmx._task_modules.triggering.pause_trigger.PauseTrigger – Gets the pause
trigger configurations for the task.
reference_trigger
nidaqmx._task_modules.triggering.reference_trigger.ReferenceTrigger
Gets the reference trigger configurations for the task.

–

start_trigger
nidaqmx._task_modules.triggering.start_trigger.StartTrigger – Gets the start
trigger configurations for the task.
sync_type
nidaqmx.constants.SyncType – Specifies the role of the device in a synchronized system. Setting
this value to SyncType.MASTER or SyncType.SLAVE enables trigger skew correction. If you enable
trigger skew correction, set this property to SyncType.MASTER on only one device, and set this property
to SyncType.SLAVE on the other devices.
nidaqmx.task.arm_start_trigger
class nidaqmx._task_modules.triggering.arm_start_trigger.ArmStartTrigger(task_handle)
Bases: object
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Represents the arm start trigger configurations for a DAQmx task.
dig_edge_dig_fltr_enable
bool – Specifies whether to apply the pulse width filter to the signal.
dig_edge_dig_fltr_min_pulse_width
float – Specifies in seconds the minimum pulse width the filter recognizes.
dig_edge_dig_fltr_timebase_rate
float – Specifies in hertz the rate of the pulse width filter timebase. NI-DAQmx uses this value to compute
settings for the filter.
dig_edge_dig_fltr_timebase_src
str – Specifies the input terminal of the signal to use as the timebase of the pulse width filter.
dig_edge_dig_sync_enable
bool – Specifies whether to synchronize recognition of transitions in the signal to the internal timebase of
the device.
dig_edge_edge
nidaqmx.constants.Edge – Specifies on which edge of a digital signal to arm the task for a Start
Trigger.
dig_edge_src
str – Specifies the name of a terminal where there is a digital signal to use as the source of the Arm Start
Trigger.
term
str – Indicates the name of the internal Arm Start Trigger terminal for the task. This property does not
return the name of the trigger source terminal.
trig_type
nidaqmx.constants.TriggerType – Specifies the type of trigger to use to arm the task for a Start
Trigger. If you configure an Arm Start Trigger, the task does not respond to a Start Trigger until the device
receives the Arm Start Trigger.
nidaqmx.task.handshake_trigger
class nidaqmx._task_modules.triggering.handshake_trigger.HandshakeTrigger(task_handle)
Bases: object
Represents the handshake trigger configurations for a DAQmx task.
interlocked_asserted_lvl
nidaqmx.constants.Level – Specifies the asserted level of the Handshake Trigger.
interlocked_src
str – Specifies the source terminal of the Handshake Trigger.
trig_type
nidaqmx.constants.TriggerType – Specifies the type of Handshake Trigger to use.
nidaqmx.task.pause_trigger
class nidaqmx._task_modules.triggering.pause_trigger.PauseTrigger(task_handle)
Bases: object
Represents the pause trigger configurations for a DAQmx task.

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anlg_lvl_coupling
nidaqmx.constants.Coupling – Specifies the coupling for the source signal of the trigger if the
source is a terminal rather than a virtual channel.
anlg_lvl_dig_fltr_enable
bool – Specifies whether to apply a digital filter to the digital output of the analog triggering circuitry (the
Analog Comparison Event). When enabled, the analog signal must stay above or below the trigger level
for the minimum pulse width before being recognized. Use filtering for noisy trigger signals that transition
in and out of the hysteresis window rapidly.
anlg_lvl_dig_fltr_min_pulse_width
float – Specifies in seconds the minimum pulse width the filter recognizes.
anlg_lvl_dig_fltr_timebase_rate
float – Specifies in hertz the rate of the digital filter timebase. NI-DAQmx uses this value to compute
settings for the filter.
anlg_lvl_dig_fltr_timebase_src
str – Specifies the terminal of the signal to use as the timebase of the digital filter.
anlg_lvl_dig_sync_enable
bool – Specifies whether to synchronize recognition of transitions in the signal to the internal timebase of
the device.
anlg_lvl_hyst
float – Specifies a hysteresis level in the units of the measurement or generation. If anlg_lvl_when is
ActiveLevel.ABOVE, the trigger does not deassert until the source signal passes below anlg_lvl_lvl minus
the hysteresis. If anlg_lvl_when is ActiveLevel.BELOW, the trigger does not deassert until the source
signal passes above anlg_lvl_lvl plus the hysteresis. Hysteresis is always enabled. Set this property to a
non-zero value to use hysteresis.
anlg_lvl_lvl
float – Specifies the threshold at which to pause the task. Specify this value in the units of the measurement
or generation. Use anlg_lvl_when to specify whether the task pauses above or below this threshold.
anlg_lvl_src
str – Specifies the name of a virtual channel or terminal where there is an analog signal to use as the source
of the trigger.
anlg_lvl_when
nidaqmx.constants.ActiveLevel – Specifies whether the task pauses above or below the threshold you specify with anlg_lvl_lvl.
anlg_win_btm
float – Specifies the lower limit of the window. Specify this value in the units of the measurement or
generation.
anlg_win_coupling
nidaqmx.constants.Coupling – Specifies the coupling for the source signal of the terminal if the
source is a terminal rather than a virtual channel.
anlg_win_dig_fltr_enable
bool – Specifies whether to apply a digital filter to the digital output of the analog triggering circuitry (the
Analog Comparison Event). When enabled, the analog signal must stay within the trigger window for the
minimum pulse width before being recognized. Use filtering for noisy trigger signals that transition in and
out of the window rapidly.
anlg_win_dig_fltr_min_pulse_width
float – Specifies in seconds the minimum pulse width the filter recognizes.

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anlg_win_dig_fltr_timebase_rate
float – Specifies in hertz the rate of the digital filter timebase. NI-DAQmx uses this value to compute
settings for the filter.
anlg_win_dig_fltr_timebase_src
str – Specifies the terminal of the signal to use as the timebase of the digital filter.
anlg_win_dig_sync_enable
bool – Specifies whether to synchronize recognition of transitions in the signal to the internal timebase of
the device.
anlg_win_src
str – Specifies the name of a virtual channel or terminal where there is an analog signal to use as the source
of the trigger.
anlg_win_top
float – Specifies the upper limit of the window. Specify this value in the units of the measurement or
generation.
anlg_win_when
nidaqmx.constants.WindowTriggerCondition2 – Specifies whether the task pauses while
the trigger signal is inside or outside the window you specify with anlg_win_btm and anlg_win_top.
dig_lvl_dig_fltr_enable
bool – Specifies whether to apply a digital filter to the trigger signal.
dig_lvl_dig_fltr_min_pulse_width
float – Specifies in seconds the minimum pulse width the filter recognizes.
dig_lvl_dig_fltr_timebase_rate
float – Specifies in hertz the rate of the pulse width filter timebase. NI-DAQmx uses this value to compute
settings for the filter.
dig_lvl_dig_fltr_timebase_src
str – Specifies the input terminal of the signal to use as the timebase of the pulse width filter.
dig_lvl_dig_sync_enable
bool – Specifies whether to synchronize recognition of transitions in the signal to the internal timebase of
the device.
dig_lvl_src
str – Specifies the name of a terminal where there is a digital signal to use as the source of the Pause
Trigger.
dig_lvl_when
nidaqmx.constants.Level – Specifies whether the task pauses while the signal is high or low.
dig_pattern_pattern
str – Specifies the digital pattern that must be met for the Pause Trigger to occur.
dig_pattern_src
nidaqmx.system.physical_channel.PhysicalChannel – Specifies the physical channels
to use for pattern matching. The order of the physical channels determines the order of the pattern. If a
port is included, the lines within the port are in ascending order.
dig_pattern_when
nidaqmx.constants.DigitalPatternCondition – Specifies if the Pause Trigger occurs when
the physical channels specified with dig_pattern_src match or differ from the digital pattern specified with
dig_pattern_pattern.

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term
str – Indicates the name of the internal Pause Trigger terminal for the task. This property does not return
the name of the trigger source terminal.
trig_type
nidaqmx.constants.TriggerType – Specifies the type of trigger to use to pause a task.
nidaqmx.task.reference_trigger
class nidaqmx._task_modules.triggering.reference_trigger.ReferenceTrigger(task_handle)
Bases: object
Represents the reference trigger configurations for a DAQmx task.
anlg_edge_coupling
nidaqmx.constants.Coupling – Specifies the coupling for the source signal of the trigger if the
source is a terminal rather than a virtual channel.
anlg_edge_dig_fltr_enable
bool – Specifies whether to apply a digital filter to the digital output of the analog triggering circuitry (the
Analog Comparison Event). When enabled, the analog signal must stay above or below the trigger level
for the minimum pulse width before being recognized. Use filtering for noisy trigger signals that transition
in and out of the hysteresis window rapidly.
anlg_edge_dig_fltr_min_pulse_width
float – Specifies in seconds the minimum pulse width thefilter recognizes.
anlg_edge_dig_fltr_timebase_rate
float – Specifies in hertz the rate of the digital filter timebase. NI-DAQmx uses this value to compute
settings for the filter.
anlg_edge_dig_fltr_timebase_src
str – Specifies the terminal of the signal to use as the timebase of the digital filter.
anlg_edge_dig_sync_enable
bool – Specifies whether to synchronize recognition of transitions in the signal to the internal timebase of
the device.
anlg_edge_hyst
float – Specifies a hysteresis level in the units of the measurement. If anlg_edge_slope is Slope1.RISING,
the trigger does not deassert until the source signal passes below anlg_edge_lvl minus the hysteresis. If
anlg_edge_slope is Slope1.FALLING, the trigger does not deassert until the source signal passes above
anlg_edge_lvl plus the hysteresis. Hysteresis is always enabled. Set this property to a non-zero value to
use hysteresis.
anlg_edge_lvl
float – Specifies in the units of the measurement the threshold at which the Reference Trigger occurs. Use
anlg_edge_slope to specify on which slope to trigger at this threshold.
anlg_edge_slope
nidaqmx.constants.Slope – Specifies on which slope of the source signal the Reference Trigger
occurs.
anlg_edge_src
str – Specifies the name of a virtual channel or terminal where there is an analog signal to use as the source
of the Reference Trigger.
anlg_win_btm
float – Specifies the lower limit of the window. Specify this value in the units of the measurement.

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anlg_win_coupling
nidaqmx.constants.Coupling – Specifies the coupling for the source signal of the trigger if the
source is a terminal rather than a virtual channel.
anlg_win_dig_fltr_enable
bool – Specifies whether to apply a digital filter to the digital output of the analog triggering circuitry (the
Analog Comparison Event). When enabled, the analog signal must stay within the trigger window for the
minimum pulse width before being recognized. Use filtering for noisy trigger signals that transition in and
out of the window rapidly.
anlg_win_dig_fltr_min_pulse_width
float – Specifies in seconds the minimum pulse width the filter recognizes.
anlg_win_dig_fltr_timebase_rate
float – Specifies in hertz the rate of the digital filter timebase. NI-DAQmx uses this value to compute
settings for the filter.
anlg_win_dig_fltr_timebase_src
str – Specifies the terminal of the signal to use as the timebase of the digital filter.
anlg_win_dig_sync_enable
bool – Specifies whether to synchronize recognition of transitions in the signal to the internal timebase of
the device.
anlg_win_src
str – Specifies the name of a virtual channel or terminal where there is an analog signal to use as the source
of the Reference Trigger.
anlg_win_top
float – Specifies the upper limit of the window. Specify this value in the units of the measurement.
anlg_win_trig_when
nidaqmx.constants.WindowTriggerCondition1 – Specifies whether the Reference Trigger
occurs when the source signal enters the window or when it leaves the window. Use anlg_win_btm and
anlg_win_top to specify the window.
auto_trig_enable
bool – Specifies whether to send a software trigger to the device when a hardware trigger is no longer
active in order to prevent a timeout.
auto_triggered
bool – Indicates whether a completed acquisition was triggered by the auto trigger. If an acquisition has
not completed after the task starts, this property returns False. This property is only applicable when
auto_trig_enable is True.
cfg_anlg_edge_ref_trig(trigger_source, pretrigger_samples, trigger_slope=, trigger_level=0.0)
Configures the task to stop the acquisition when the device acquires all pretrigger samples; an analog signal
reaches the level you specify; and the device acquires all post-trigger samples. When you use a Reference
Trigger, the default for the read RelativeTo property is first_pretrigger_sample with a read Offset of 0.
Parameters
• trigger_source (str) – Is the name of a virtual channel or terminal where there is
an analog signal to use as the source of the trigger.
• pretrigger_samples (int) – Specifies the minimum number of samples to acquire
per channel before recognizing the Reference Trigger. The number of post-trigger samples
per channel is equal to number of samples per channel in the DAQmx Timing function
minus pretrigger_samples.

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• trigger_slope (Optional[nidaqmx.constants.Slope]) – Specifies on
which slope of the signal the Reference Trigger occurs.
• trigger_level (Optional[float]) – Specifies at what threshold to trigger. Specify this value in the units of the measurement or generation. Use trigger_slope to specify
on which slope to trigger at this threshold.
cfg_anlg_window_ref_trig(trigger_source,
window_top,
window_bottom,
pretrigger_samples,
trigger_when=)
Configures the task to stop the acquisition when the device acquires all pretrigger samples; an analog
signal enters or leaves a range you specify; and the device acquires all post- trigger samples. When you
use a Reference Trigger, the default for the read RelativeTo property is first_pretrigger_sample with a
read Offset of 0.
Parameters
• trigger_source (str) – Is the name of a virtual channel or terminal where there is
an analog signal to use as the source of the trigger.
• window_top (float) – Is the upper limit of the window. Specify this value in the units
of the measurement or generation.
• window_bottom (float) – Is the lower limit of the window. Specify this value in the
units of the measurement or generation.
• pretrigger_samples (int) – Specifies the minimum number of samples to acquire
per channel before recognizing the Reference Trigger. The number of post-trigger samples
per channel is equal to number of samples per channel in the DAQmx Timing function
minus pretrigger_samples.
• trigger_when
(Optional[nidaqmx.constants.
WindowTriggerCondition1]) – Specifies whether the Reference Trigger occurs
when the signal enters the window or when it leaves the window. Use window_bottom
and window_top to specify the limits of the window.
cfg_dig_edge_ref_trig(trigger_source, pretrigger_samples, trigger_edge=)
Configures the task to stop the acquisition when the device acquires all pretrigger samples, detects a rising
or falling edge of a digital signal, and acquires all posttrigger samples. When you use a Reference Trigger,
the default for the read RelativeTo property is first_pretrigger_sample with a read Offset of 0.
Parameters
• trigger_source (str) – Specifies the name of a terminal where there is a digital
signal to use as the source of the trigger.
• pretrigger_samples (int) – Specifies the minimum number of samples to acquire
per channel before recognizing the Reference Trigger. The number of post-trigger samples
per channel is equal to number of samples per channel in the DAQmx Timing function
minus pretrigger_samples.
• trigger_edge (Optional[nidaqmx.constants.Edge]) – Specifies on which
edge of the digital signal the Reference Trigger occurs.
cfg_dig_pattern_ref_trig(trigger_source,
trigger_pattern,
pretrigger_samples,
trigger_when=)
Configures the task to stop the acquisition when the device acquires all pretrigger samples, matches a
digital pattern, and acquires all posttrigger samples. When you use a Reference Trigger, the default for the
read RelativeTo property is First PretriggerSample with a read Offset of zero.
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Parameters
• trigger_source (str) – Specifies the physical channels to use for pattern matching.
The order of the physical channels determines the order of the pattern. If a port is included,
the order of the physical channels within the port is in ascending order.
• trigger_pattern (str) – Specifies the digital pattern that must be met for the trigger
to occur.
• pretrigger_samples (int) – Specifies the minimum number of samples to acquire
per channel before recognizing the Reference Trigger. The number of post-trigger samples
per channel is equal to number of samples per channel in the DAQmx Timing function
minus pretrigger_samples.
• trigger_when
(Optional[nidaqmx.constants.
DigitalPatternCondition]) – Specifies the condition under which the trigger
occurs.
delay
float – Specifies in seconds the time to wait after the device receives the Reference Trigger before switching
from pretrigger to posttrigger samples.
dig_edge_dig_fltr_enable
bool – Specifies whether to apply a digital filter to the trigger signal.
dig_edge_dig_fltr_min_pulse_width
float – Specifies in seconds the minimum pulse width the filter recognizes.
dig_edge_dig_fltr_timebase_rate
float – Specifies in hertz the rate of the digital filter timebase. NI-DAQmx uses this value to compute
settings for the filter.
dig_edge_dig_fltr_timebase_src
str – Specifies the terminal of the signal to use as the timebase of the digital filter.
dig_edge_dig_sync_enable
bool – Specifies whether to synchronize recognition of transitions in the signal to the internal timebase of
the device.
dig_edge_edge
nidaqmx.constants.Edge – Specifies on what edge of a digital pulse the Reference Trigger occurs.
dig_edge_src
str – Specifies the name of a terminal where there is a digital signal to use as the source of the Reference
Trigger.
dig_pattern_pattern
str – Specifies the digital pattern that must be met for the Reference Trigger to occur.
dig_pattern_src
nidaqmx.system.physical_channel.PhysicalChannel – Specifies the physical channels
to use for pattern matching. The order of the physical channels determines the order of the pattern. If a
port is included, the order of the physical channels within the port is in ascending order.
dig_pattern_trig_when
nidaqmx.constants.DigitalPatternCondition – Specifies whether the Reference Trigger
occurs when the physical channels specified with dig_pattern_src match or differ from the digital pattern
specified with dig_pattern_pattern.
disable_ref_trig()
Disables reference triggering for the measurement.

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pretrig_samples
int – Specifies the minimum number of pretrigger samples to acquire from each channel before recognizing
the reference trigger. Post-trigger samples per channel are equal to samp_quant_samp_per_chan minus
the number of pretrigger samples per channel.
term
str – Indicates the name of the internal Reference Trigger terminal for the task. This property does not
return the name of the trigger source terminal.
trig_type
nidaqmx.constants.TriggerType – Specifies the type of trigger to use to mark a reference point
for the measurement.
nidaqmx.task.start_trigger
class nidaqmx._task_modules.triggering.start_trigger.StartTrigger(task_handle)
Bases: object
Represents the start trigger configurations for a DAQmx task.
anlg_edge_coupling
nidaqmx.constants.Coupling – Specifies the coupling for the source signal of the trigger if the
source is a terminal rather than a virtual channel.
anlg_edge_dig_fltr_enable
bool – Specifies whether to apply a digital filter to the digital output of the analog triggering circuitry (the
Analog Comparison Event). When enabled, the analog signal must stay above or below the trigger level
for the minimum pulse width before being recognized. Use filtering for noisy trigger signals that transition
in and out of the hysteresis window rapidly.
anlg_edge_dig_fltr_min_pulse_width
float – Specifies in seconds the minimum pulse width the filter recognizes.
anlg_edge_dig_fltr_timebase_rate
float – Specifies in hertz the rate of the digital filter timebase. NI-DAQmx uses this value to compute
settings for the filter.
anlg_edge_dig_fltr_timebase_src
str – Specifies the terminal of the signal to use as the timebase of the digital filter.
anlg_edge_dig_sync_enable
bool – Specifies whether to synchronize recognition of transitions in the signal to the internal timebase of
the device.
anlg_edge_hyst
float – Specifies a hysteresis level in the units of the measurement or generation. If anlg_edge_slope is
Slope1.RISING, the trigger does not deassert until the source signal passes below anlg_edge_lvl minus
the hysteresis. If anlg_edge_slope is Slope1.FALLING, the trigger does not deassert until the source
signal passes above anlg_edge_lvl plus the hysteresis. Hysteresis is always enabled. Set this property to a
non-zero value to use hysteresis.
anlg_edge_lvl
float – Specifies at what threshold in the units of the measurement or generation to start acquiring or
generating samples. Use anlg_edge_slope to specify on which slope to trigger on this threshold.
anlg_edge_slope
nidaqmx.constants.Slope – Specifies on which slope of the trigger signal to start acquiring or
generating samples.

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anlg_edge_src
str – Specifies the name of a virtual channel or terminal where there is an analog signal to use as the source
of the Start Trigger.
anlg_win_btm
float – Specifies the lower limit of the window. Specify this value in the units of the measurement or
generation.
anlg_win_coupling
nidaqmx.constants.Coupling – Specifies the coupling for the source signal of the trigger if the
source is a terminal rather than a virtual channel.
anlg_win_dig_fltr_enable
bool – Specifies whether to apply a digital filter to the digital output of the analog triggering circuitry (the
Analog Comparison Event). When enabled, the analog signal must stay within the trigger window for the
minimum pulse width before being recognized. Use filtering for noisy trigger signals that transition in and
out of the window rapidly.
anlg_win_dig_fltr_min_pulse_width
float – Specifies in seconds the minimum pulse width the filter recognizes.
anlg_win_dig_fltr_timebase_rate
float – Specifies in hertz the rate of the digital filter timebase. NI-DAQmx uses this value to compute
settings for the filter.
anlg_win_dig_fltr_timebase_src
str – Specifies the terminal of the signal to use as the timebase of the digital filter.
anlg_win_dig_sync_enable
bool – Specifies whether to synchronize recognition of transitions in the signal to the internal timebase of
the device.
anlg_win_src
str – Specifies the name of a virtual channel or terminal where there is an analog signal to use as the source
of the Start Trigger.
anlg_win_top
float – Specifies the upper limit of the window. Specify this value in the units of the measurement or
generation.
anlg_win_trig_when
nidaqmx.constants.WindowTriggerCondition1 – Specifies whether the task starts acquiring
or generating samples when the signal enters or leaves the window you specify with anlg_win_btm and
anlg_win_top.
cfg_anlg_edge_start_trig(trigger_source=u’‘, trigger_slope=, trigger_level=0.0)
Configures the task to start acquiring or generating samples when an analog signal crosses the level you
specify.
Parameters
• trigger_source (Optional[str]) – Is the name of a virtual channel or terminal
where there is an analog signal to use as the source of the trigger.
• trigger_slope (Optional[nidaqmx.constants.Slope]) – Specifies on
which slope of the signal to start acquiring or generating samples when the signal crosses
trigger_level.
• trigger_level (Optional[float]) – Specifies at what threshold to start acquiring or generating samples. Specify this value in the units of the measurement or generation. Use trigger_slope to specify on which slope to trigger at this threshold.
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cfg_anlg_window_start_trig(window_top,
window_bottom,
trigger_source=u’‘,
trigger_when=)
Configures the task to start acquiring or generating samples when an analog signal enters or leaves a range
you specify.
Parameters
• window_top (float) – Is the upper limit of the window. Specify this value in the units
of the measurement or generation.
• window_bottom (float) – Is the lower limit of the window. Specify this value in the
units of the measurement or generation.
• trigger_source (Optional[str]) – Is the name of a virtual channel or terminal
where there is an analog signal to use as the source of the trigger.
• trigger_when
(Optional[nidaqmx.constants.
WindowTriggerCondition1]) – Specifies whether the task starts measuring
or generating samples when the signal enters the window or when it leaves the window.
Use window_bottom and window_top to specify the limits of the window.
cfg_dig_edge_start_trig(trigger_source, trigger_edge=)
Configures the task to start acquiring or generating samples on a rising or falling edge of a digital signal.
Parameters
• trigger_source (str) – Specifies the name of a terminal where there is a digital
signal to use as the source of the trigger.
• trigger_edge (Optional[nidaqmx.constants.Edge]) – Specifies on which
edge of the digital signal to start acquiring or generating samples.
cfg_dig_pattern_start_trig(trigger_source,
trigger_pattern,
trigger_when=)
Configures a task to start acquiring or generating samples when a digital pattern is matched.
Parameters
• trigger_source (str) – Specifies the physical channels to use for pattern matching.
The order of the physical channels determines the order of the pattern. If a port is included,
the order of the physical channels within the port is in ascending order.
• trigger_pattern (str) – Specifies the digital pattern that must be met for the trigger
to occur.
• trigger_when
(Optional[nidaqmx.constants.
DigitalPatternCondition]) – Specifies the condition under which the trigger
occurs.
delay
float – Specifies an amount of time to wait after the Start Trigger is received before acquiring or generating
the first sample. This value is in the units you specify with delay_units.
delay_units
nidaqmx.constants.DigitalWidthUnits – Specifies the units of delay.
dig_edge_dig_fltr_enable
bool – Specifies whether to apply a digital filter to the trigger signal.
dig_edge_dig_fltr_min_pulse_width
float – Specifies in seconds the minimum pulse width the filter recognizes.

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dig_edge_dig_fltr_timebase_rate
float – Specifies in hertz the rate of the pulse width filter timebase. NI-DAQmx uses this value to compute
settings for the filter.
dig_edge_dig_fltr_timebase_src
str – Specifies the input terminal of the signal to use as the timebase of the pulse width filter.
dig_edge_dig_sync_enable
bool – Specifies whether to synchronize recognition of transitions in the signal to the internal timebase of
the device. If you set this property to True, the device does not recognize and act upon the trigger until the
next pulse of the internal timebase.
dig_edge_edge
nidaqmx.constants.Edge – Specifies on which edge of a digital pulse to start acquiring or generating samples.
dig_edge_src
str – Specifies the name of a terminal where there is a digital signal to use as the source of the Start Trigger.
dig_pattern_pattern
str – Specifies the digital pattern that must be met for the Start Trigger to occur.
dig_pattern_src
nidaqmx.system.physical_channel.PhysicalChannel – Specifies the physical channels
to use for pattern matching. The order of the physical channels determines the order of the pattern. If a
port is included, the order of the physical channels within the port is in ascending order.
dig_pattern_trig_when
nidaqmx.constants.DigitalPatternCondition – Specifies whether the Start Trigger occurs
when the physical channels specified with dig_pattern_src match or differ from the digital pattern specified with dig_pattern_pattern.
disable_start_trig()
Configures the task to start acquiring or generating samples immediately upon starting the task.
retriggerable
bool – Specifies whether a finite task resets and waits for another Start Trigger after the task completes.
When you set this property to True, the device performs a finite acquisition or generation each time the
Start Trigger occurs until the task stops. The device ignores a trigger if it is in the process of acquiring or
generating signals.
term
str – Indicates the name of the internal Start Trigger terminal for the task. This property does not return
the name of the trigger source terminal.
trig_type
nidaqmx.constants.TriggerType – Specifies the type of trigger to use to start a task.

nidaqmx.types
class nidaqmx.types.AOExpirationState(physical_channel, expiration_state, output_type)
Bases: tuple
expiration_state
Alias for field number 1
output_type
Alias for field number 2

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physical_channel
Alias for field number 0
class nidaqmx.types.AOPowerUpState(physical_channel, power_up_state, channel_type)
Bases: tuple
channel_type
Alias for field number 2
physical_channel
Alias for field number 0
power_up_state
Alias for field number 1
class nidaqmx.types.CDAQSyncConnection(output_port, input_port)
Bases: tuple
input_port
Alias for field number 1
output_port
Alias for field number 0
class nidaqmx.types.COExpirationState(physical_channel, expiration_state)
Bases: tuple
expiration_state
Alias for field number 1
physical_channel
Alias for field number 0
class nidaqmx.types.CtrFreq(freq, duty_cycle)
Bases: tuple
duty_cycle
Alias for field number 1
freq
Alias for field number 0
class nidaqmx.types.CtrTick(high_tick, low_tick)
Bases: tuple
high_tick
Alias for field number 0
low_tick
Alias for field number 1
class nidaqmx.types.CtrTime(high_time, low_time)
Bases: tuple
high_time
Alias for field number 0
low_time
Alias for field number 1
class nidaqmx.types.DOExpirationState(physical_channel, expiration_state)
Bases: tuple

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expiration_state
Alias for field number 1
physical_channel
Alias for field number 0
class nidaqmx.types.DOPowerUpState(physical_channel, power_up_state)
Bases: tuple
physical_channel
Alias for field number 0
power_up_state
Alias for field number 1
class nidaqmx.types.DOResistorPowerUpState(physical_channel, power_up_state)
Bases: tuple
physical_channel
Alias for field number 0
power_up_state
Alias for field number 1

nidaqmx.utils
nidaqmx.utils.flatten_channel_string(channel_names)
Converts a list of channel names to a comma-delimited list of names.
You can use this method to convert a list of physical or virtual channel names to a single string prior to using
the DAQmx Create Channel methods or instantiating a DAQmx Task object.
Parameters channel_names (List[str]) – The list of physical or virtual channel names.
Returns The resulting comma-delimited list of physical or virtual channel names.
Return type str
nidaqmx.utils.unflatten_channel_string(channel_names)
Converts a comma-delimited list of channel names to a list of names.
You can use this method to convert a comma-delimited list or range of physical or virtual channels into a list of
physical or virtual channel names.
Parameters channel_names (str) – The list or range of physical or virtual channels.
Returns The list of physical or virtual channel names. Each element of the list contains a single
channel.
Return type List[str]

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CHAPTER

Indices and Tables

• genindex
• modindex

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Python Module Index

237
nidaqmx._task_modules.triggering.reference_trigger,
nidaqmx._task_modules.ai_channel_collection,
240
156
nidaqmx._task_modules.triggering.start_trigger,
nidaqmx._task_modules.ao_channel_collection,
244
201
nidaqmx._task_modules.channel_collection,nidaqmx._task_modules.triggers, 236
nidaqmx.constants, 17
156
nidaqmx.errors, 51
nidaqmx._task_modules.channels.ai_channel,
nidaqmx.scale, 52
119
nidaqmx.stream_readers, 56
nidaqmx._task_modules.channels.ao_channel,
nidaqmx.stream_writers, 77
131
nidaqmx._task_modules.channels.channel, nidaqmx.system._collections.device_collection,
96
118
nidaqmx.system._collections.persisted_channel_colle
nidaqmx._task_modules.channels.ci_channel,
96
135
nidaqmx.system._collections.persisted_scale_collect
nidaqmx._task_modules.channels.co_channel,
97
149
nidaqmx.system._collections.persisted_task_collecti
nidaqmx._task_modules.channels.di_channel,
97
152
nidaqmx.system._collections.physical_channel_collec
nidaqmx._task_modules.channels.do_channel,
97
154
nidaqmx.system._watchdog_modules.expiration_state,
nidaqmx._task_modules.ci_channel_collection,
111
203
nidaqmx.system._watchdog_modules.expiration_states_
nidaqmx._task_modules.co_channel_collection,
111
213
nidaqmx.system.device,
98
nidaqmx._task_modules.di_channel_collection,
nidaqmx.system.physical_channel,
104
215
nidaqmx.system.storage.persisted_channel,
nidaqmx._task_modules.do_channel_collection,
107
216
nidaqmx.system.storage.persisted_scale,
nidaqmx._task_modules.export_signals,
107
216
nidaqmx.system.storage.persisted_task,
nidaqmx._task_modules.in_stream, 220
108
nidaqmx._task_modules.out_stream, 226
nidaqmx.system.system,
91
nidaqmx._task_modules.timing, 229
nidaqmx.system.watchdog,
109
nidaqmx._task_modules.triggering.arm_start_trigger,
nidaqmx.task,
112
236
nidaqmx.types, 247
nidaqmx._task_modules.triggering.handshake_trigger,
nidaqmx.utils, 249
237
nidaqmx._task_modules.triggering.pause_trigger,

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Python Module Index

Index

Symbols

(nidaqmx.constants.UsageTypeAI attribute), 47
ACCELERATION_ACCELEROMETER_CURRENT_INPUT
__init__() (nidaqmx.scale.Scale method), 52
(nidaqmx.constants.UsageTypeAI attribute), 47
__init__() (nidaqmx.system.device.Device method), 98
ACCELERATION_CHARGE
__init__() (nidaqmx.system.physical_channel.PhysicalChannel
(nidaqmx.constants.UsageTypeAI attribute), 47
method), 104
AccelSensitivityUnits
(class in nidaqmx.constants), 18
__init__() (nidaqmx.system.storage.persisted_channel.PersistedChannel
AccelUnits (class in nidaqmx.constants), 18
method), 107
accessory_insertion_or_removal_detected
__init__() (nidaqmx.system.storage.persisted_scale.PersistedScale
(nidaqmx._task_modules.in_stream.InStream
method), 107
attribute), 220
__init__() (nidaqmx.system.storage.persisted_task.PersistedTask
accessory_insertion_or_removal_detected
method), 108
(nidaqmx._task_modules.out_stream.OutStream
__init__()
(nidaqmx.system.watchdog.WatchdogTask
attribute), 226
method), 109
accessory_product_nums
__init__() (nidaqmx.task.Task method), 112
(nidaqmx.system.device.Device
attribute),
__weakref__ (nidaqmx.scale.Scale attribute), 52
98
__weakref__ (nidaqmx.system.device.Device attribute),
accessory_product_types
98
(nidaqmx.system.device.Device
attribute),
__weakref__ (nidaqmx.system.physical_channel.PhysicalChannel
98
attribute), 104
accessory_serial_nums (nidaqmx.system.device.Device
__weakref__ (nidaqmx.system.storage.persisted_channel.PersistedChannel
attribute), 99
attribute), 107
ACExcitWireMode
(class in nidaqmx.constants), 17
__weakref__ (nidaqmx.system.storage.persisted_scale.PersistedScale
ACQUIRED_INTO_BUFFER
attribute), 108
__weakref__ (nidaqmx.system.storage.persisted_task.PersistedTask (nidaqmx.constants.EveryNSamplesEventType
attribute), 26
attribute), 108
AcquisitionType
(class in nidaqmx.constants), 18
__weakref__ (nidaqmx.system.watchdog.WatchdogTask
Action
(class
in
nidaqmx.constants),
19
attribute), 109
ACTIVE
(nidaqmx.constants.ActiveOrInactiveEdgeSelection
__weakref__ (nidaqmx.task.Task attribute), 112
attribute), 19
ACTIVE_DRIVE
(nidaqmx.constants.DigitalDriveType
A
attribute), 25
A (nidaqmx.constants.ShuntCalSelect attribute), 39
ACTIVE_HIGH (nidaqmx.constants.Polarity attribute),
A (nidaqmx.constants.ShuntResistorSelect attribute), 39
33
AAND_B (nidaqmx.constants.ShuntCalSelect attribute),
ACTIVE_LOW (nidaqmx.constants.Polarity attribute),
39
33
ABOVE (nidaqmx.constants.ActiveLevel attribute), 19
ActiveLevel (class in nidaqmx.constants), 19
AC (nidaqmx.constants.Coupling attribute), 24
ActiveOrInactiveEdgeSelection
(class
in
AccelChargeSensitivityUnits
(class
in
nidaqmx.constants), 19
nidaqmx.constants), 18
ADCTimingMode (class in nidaqmx.constants), 17
ACCELERATION_4_WIRE_DC_VOLTAGE
add_ai_accel_4_wire_dc_voltage_chan()
255

NI-DAQmx Python API Documentation, Release 0.5.0

(nidaqmx._task_modules.ai_channel_collection.AIChannelCollection
(nidaqmx._task_modules.ai_channel_collection.AIChannelCollec
method), 157
method), 175
add_ai_accel_chan() (nidaqmx._task_modules.ai_channel_collection.AIChannelCollection
add_ai_rtd_chan() (nidaqmx._task_modules.ai_channel_collection.AIChann
method), 158
method), 176
add_ai_accel_charge_chan()
add_ai_strain_gage_chan()
(nidaqmx._task_modules.ai_channel_collection.AIChannelCollection
(nidaqmx._task_modules.ai_channel_collection.AIChannelCollec
method), 158
method), 177
add_ai_bridge_chan() (nidaqmx._task_modules.ai_channel_collection.AIChannelCollection
add_ai_temp_built_in_sensor_chan()
method), 159
(nidaqmx._task_modules.ai_channel_collection.AIChannelCollec
add_ai_charge_chan() (nidaqmx._task_modules.ai_channel_collection.AIChannelCollection
method), 178
method), 160
add_ai_thrmcpl_chan() (nidaqmx._task_modules.ai_channel_collection.AIC
add_ai_current_chan() (nidaqmx._task_modules.ai_channel_collection.AIChannelCollection
method), 178
method), 161
add_ai_thrmstr_chan_iex()
add_ai_current_rms_chan()
(nidaqmx._task_modules.ai_channel_collection.AIChannelCollec
(nidaqmx._task_modules.ai_channel_collection.AIChannelCollection
method), 179
method), 161
add_ai_thrmstr_chan_vex()
add_ai_force_bridge_polynomial_chan()
(nidaqmx._task_modules.ai_channel_collection.AIChannelCollec
(nidaqmx._task_modules.ai_channel_collection.AIChannelCollection
method), 180
method), 162
add_ai_torque_bridge_polynomial_chan()
add_ai_force_bridge_table_chan()
(nidaqmx._task_modules.ai_channel_collection.AIChannelCollec
(nidaqmx._task_modules.ai_channel_collection.AIChannelCollection
method), 181
method), 163
add_ai_torque_bridge_table_chan()
add_ai_force_bridge_two_point_lin_chan()
(nidaqmx._task_modules.ai_channel_collection.AIChannelCollec
(nidaqmx._task_modules.ai_channel_collection.AIChannelCollection
method), 182
method), 164
add_ai_torque_bridge_two_point_lin_chan()
add_ai_force_iepe_chan()
(nidaqmx._task_modules.ai_channel_collection.AIChannelCollec
(nidaqmx._task_modules.ai_channel_collection.AIChannelCollection
method), 183
method), 166
add_ai_velocity_iepe_chan()
add_ai_freq_voltage_chan()
(nidaqmx._task_modules.ai_channel_collection.AIChannelCollec
(nidaqmx._task_modules.ai_channel_collection.AIChannelCollection
method), 184
method), 167
add_ai_voltage_chan() (nidaqmx._task_modules.ai_channel_collection.AIC
add_ai_microphone_chan()
method), 185
(nidaqmx._task_modules.ai_channel_collection.AIChannelCollection
add_ai_voltage_chan_with_excit()
method), 167
(nidaqmx._task_modules.ai_channel_collection.AIChannelCollec
add_ai_pos_eddy_curr_prox_probe_chan()
method), 186
(nidaqmx._task_modules.ai_channel_collection.AIChannelCollection
add_ai_voltage_rms_chan()
method), 168
(nidaqmx._task_modules.ai_channel_collection.AIChannelCollec
add_ai_pos_lvdt_chan() (nidaqmx._task_modules.ai_channel_collection.AIChannelCollection
method), 187
method), 169
add_ao_current_chan() (nidaqmx._task_modules.ao_channel_collection.AO
add_ai_pos_rvdt_chan() (nidaqmx._task_modules.ai_channel_collection.AIChannelCollection
method), 201
method), 170
add_ao_func_gen_chan()
add_ai_pressure_bridge_polynomial_chan()
(nidaqmx._task_modules.ao_channel_collection.AOChannelColle
(nidaqmx._task_modules.ai_channel_collection.AIChannelCollection
method), 201
method), 171
add_ao_voltage_chan() (nidaqmx._task_modules.ao_channel_collection.AO
add_ai_pressure_bridge_table_chan()
method), 202
(nidaqmx._task_modules.ai_channel_collection.AIChannelCollection
add_cdaq_sync_connection()
method), 172
(nidaqmx.system.system.System
method),
add_ai_pressure_bridge_two_point_lin_chan()
91
(nidaqmx._task_modules.ai_channel_collection.AIChannelCollection
add_ci_ang_encoder_chan()
method), 173
(nidaqmx._task_modules.ci_channel_collection.CIChannelCollec
add_ai_resistance_chan()
method), 203
(nidaqmx._task_modules.ai_channel_collection.AIChannelCollection
add_ci_ang_velocity_chan()
method), 174
(nidaqmx._task_modules.ci_channel_collection.CIChannelCollec
add_ai_rosette_strain_gage_chan()
method), 204

256

Index

NI-DAQmx Python API Documentation, Release 0.5.0

add_ci_count_edges_chan()
(nidaqmx._task_modules.ai_channel_collection.AIChannelCollec
(nidaqmx._task_modules.ci_channel_collection.CIChannelCollection
method), 187
method), 204
add_teds_ai_bridge_chan()
add_ci_duty_cycle_chan()
(nidaqmx._task_modules.ai_channel_collection.AIChannelCollec
(nidaqmx._task_modules.ci_channel_collection.CIChannelCollection
method), 188
method), 205
add_teds_ai_current_chan()
add_ci_freq_chan() (nidaqmx._task_modules.ci_channel_collection.CIChannelCollection
(nidaqmx._task_modules.ai_channel_collection.AIChannelCollec
method), 205
method), 189
add_ci_gps_timestamp_chan()
add_teds_ai_force_bridge_chan()
(nidaqmx._task_modules.ci_channel_collection.CIChannelCollection
(nidaqmx._task_modules.ai_channel_collection.AIChannelCollec
method), 206
method), 190
add_ci_lin_encoder_chan()
add_teds_ai_force_iepe_chan()
(nidaqmx._task_modules.ci_channel_collection.CIChannelCollection
(nidaqmx._task_modules.ai_channel_collection.AIChannelCollec
method), 207
method), 190
add_ci_lin_velocity_chan()
add_teds_ai_microphone_chan()
(nidaqmx._task_modules.ci_channel_collection.CIChannelCollection
(nidaqmx._task_modules.ai_channel_collection.AIChannelCollec
method), 208
method), 191
add_ci_period_chan() (nidaqmx._task_modules.ci_channel_collection.CIChannelCollection
add_teds_ai_pos_lvdt_chan()
method), 208
(nidaqmx._task_modules.ai_channel_collection.AIChannelCollec
add_ci_pulse_chan_freq()
method), 192
(nidaqmx._task_modules.ci_channel_collection.CIChannelCollection
add_teds_ai_pos_rvdt_chan()
method), 209
(nidaqmx._task_modules.ai_channel_collection.AIChannelCollec
add_ci_pulse_chan_ticks()
method), 193
(nidaqmx._task_modules.ci_channel_collection.CIChannelCollection
add_teds_ai_pressure_bridge_chan()
method), 210
(nidaqmx._task_modules.ai_channel_collection.AIChannelCollec
add_ci_pulse_chan_time()
method), 194
(nidaqmx._task_modules.ci_channel_collection.CIChannelCollection
add_teds_ai_resistance_chan()
method), 210
(nidaqmx._task_modules.ai_channel_collection.AIChannelCollec
add_ci_pulse_width_chan()
method), 194
(nidaqmx._task_modules.ci_channel_collection.CIChannelCollection
add_teds_ai_rtd_chan() (nidaqmx._task_modules.ai_channel_collection.AIC
method), 211
method), 195
add_ci_semi_period_chan()
add_teds_ai_strain_gage_chan()
(nidaqmx._task_modules.ci_channel_collection.CIChannelCollection
(nidaqmx._task_modules.ai_channel_collection.AIChannelCollec
method), 212
method), 196
add_ci_two_edge_sep_chan()
add_teds_ai_thrmcpl_chan()
(nidaqmx._task_modules.ci_channel_collection.CIChannelCollection
(nidaqmx._task_modules.ai_channel_collection.AIChannelCollec
method), 212
method), 196
add_co_pulse_chan_freq()
add_teds_ai_thrmstr_chan_iex()
(nidaqmx._task_modules.co_channel_collection.COChannelCollection
(nidaqmx._task_modules.ai_channel_collection.AIChannelCollec
method), 213
method), 197
add_co_pulse_chan_ticks()
add_teds_ai_thrmstr_chan_vex()
(nidaqmx._task_modules.co_channel_collection.COChannelCollection
(nidaqmx._task_modules.ai_channel_collection.AIChannelCollec
method), 214
method), 198
add_co_pulse_chan_time()
add_teds_ai_torque_bridge_chan()
(nidaqmx._task_modules.co_channel_collection.COChannelCollection
(nidaqmx._task_modules.ai_channel_collection.AIChannelCollec
method), 214
method), 198
add_di_chan() (nidaqmx._task_modules.di_channel_collection.DIChannelCollection
add_teds_ai_voltage_chan()
method), 215
(nidaqmx._task_modules.ai_channel_collection.AIChannelCollec
add_do_chan() (nidaqmx._task_modules.do_channel_collection.DOChannelCollection
method), 199
method), 216
add_teds_ai_voltage_chan_with_excit()
add_global_channels() (nidaqmx.task.Task method), 112
(nidaqmx._task_modules.ai_channel_collection.AIChannelCollec
add_network_device() (nidaqmx.system.device.Device
method), 200
static method), 99
ADV_CMPLT_EVENT (nidaqmx.constants.Signal atadd_teds_ai_accel_chan()
tribute), 39

Index

257

NI-DAQmx Python API Documentation, Release 0.5.0

adv_cmplt_event_delay (nidaqmx._task_modules.export_signals.ExportSignals
ai_accel_units (nidaqmx._task_modules.channels.ai_channel.AIChannel
attribute), 216
attribute), 120
adv_cmplt_event_output_term
ai_acceld_b_ref (nidaqmx._task_modules.channels.ai_channel.AIChannel
(nidaqmx._task_modules.export_signals.ExportSignals
attribute), 120
attribute), 217
ai_adc_custom_timing_mode
adv_cmplt_event_pulse_polarity
(nidaqmx._task_modules.channels.ai_channel.AIChannel
(nidaqmx._task_modules.export_signals.ExportSignals
attribute), 120
attribute), 217
ai_adc_timing_mode (nidaqmx._task_modules.channels.ai_channel.AIChan
adv_cmplt_event_pulse_width
attribute), 120
(nidaqmx._task_modules.export_signals.ExportSignals
ai_atten (nidaqmx._task_modules.channels.ai_channel.AIChannel
attribute), 217
attribute), 120
adv_trig_output_term (nidaqmx._task_modules.export_signals.ExportSignals
ai_auto_zero_mode (nidaqmx._task_modules.channels.ai_channel.AIChann
attribute), 217
attribute), 120
adv_trig_pulse_polarity (nidaqmx._task_modules.export_signals.ExportSignals
ai_averaging_win_size (nidaqmx._task_modules.channels.ai_channel.AICh
attribute), 217
attribute), 120
adv_trig_pulse_width (nidaqmx._task_modules.export_signals.ExportSignals
ai_bridge_balance_coarse_pot
attribute), 217
(nidaqmx._task_modules.channels.ai_channel.AIChannel
adv_trig_pulse_width_units
attribute), 120
(nidaqmx._task_modules.export_signals.ExportSignals
ai_bridge_balance_fine_pot
attribute), 217
(nidaqmx._task_modules.channels.ai_channel.AIChannel
ADVANCE (nidaqmx.constants.TriggerUsage attribute),
attribute), 120
44
ai_bridge_cfg (nidaqmx._task_modules.channels.ai_channel.AIChannel
ADVANCE_TRIGGER (nidaqmx.constants.Signal atattribute), 120
tribute), 39
ai_bridge_electrical_units
ADVANCE_TRIGGER (nidaqmx.constants.SoftwareTrigger
(nidaqmx._task_modules.channels.ai_channel.AIChannel
attribute), 40
attribute), 120
AHIGH_BHIGH (nidaqmx.constants.EncoderZIndexPhase ai_bridge_initial_ratio (nidaqmx._task_modules.channels.ai_channel.AICha
attribute), 26
attribute), 120
AHIGH_BLOW (nidaqmx.constants.EncoderZIndexPhase ai_bridge_initial_voltage
attribute), 26
(nidaqmx._task_modules.channels.ai_channel.AIChannel
ai_ac_excit_freq (nidaqmx._task_modules.channels.ai_channel.AIChannel
attribute), 120
attribute), 119
ai_bridge_nom_resistance
ai_ac_excit_sync_enable
(nidaqmx._task_modules.channels.ai_channel.AIChannel
(nidaqmx._task_modules.channels.ai_channel.AIChannel attribute), 121
attribute), 119
ai_bridge_physical_units
ai_ac_excit_wire_mode (nidaqmx._task_modules.channels.ai_channel.AIChannel
(nidaqmx._task_modules.channels.ai_channel.AIChannel
attribute), 119
attribute), 121
ai_accel_4_wire_dc_voltage_sensitivity
ai_bridge_poly_forward_coeff
(nidaqmx._task_modules.channels.ai_channel.AIChannel (nidaqmx._task_modules.channels.ai_channel.AIChannel
attribute), 119
attribute), 121
ai_accel_4_wire_dc_voltage_sensitivity_units
ai_bridge_poly_reverse_coeff
(nidaqmx._task_modules.channels.ai_channel.AIChannel (nidaqmx._task_modules.channels.ai_channel.AIChannel
attribute), 119
attribute), 121
ai_accel_charge_sensitivity
ai_bridge_rngs
(nidaqmx.system.device.Device
at(nidaqmx._task_modules.channels.ai_channel.AIChannel tribute), 99
attribute), 119
ai_bridge_scale_type (nidaqmx._task_modules.channels.ai_channel.AIChan
ai_accel_charge_sensitivity_units
attribute), 121
(nidaqmx._task_modules.channels.ai_channel.AIChannel
ai_bridge_shunt_cal_enable
attribute), 119
(nidaqmx._task_modules.channels.ai_channel.AIChannel
ai_accel_sensitivity (nidaqmx._task_modules.channels.ai_channel.AIChannel
attribute), 121
attribute), 119
ai_bridge_shunt_cal_gain_adjust
ai_accel_sensitivity_units
(nidaqmx._task_modules.channels.ai_channel.AIChannel
(nidaqmx._task_modules.channels.ai_channel.AIChannel attribute), 121
attribute), 120
ai_bridge_shunt_cal_select

258

Index

NI-DAQmx Python API Documentation, Release 0.5.0

(nidaqmx._task_modules.channels.ai_channel.AIChannel attribute), 229
attribute), 121
ai_conv_dig_fltr_timebase_rate
ai_bridge_shunt_cal_shunt_cal_a_actual_resistance
(nidaqmx._task_modules.timing.Timing
(nidaqmx._task_modules.channels.ai_channel.AIChannel attribute), 229
attribute), 121
ai_conv_dig_fltr_timebase_src
ai_bridge_shunt_cal_shunt_cal_a_resistance
(nidaqmx._task_modules.timing.Timing
(nidaqmx._task_modules.channels.ai_channel.AIChannel attribute), 229
attribute), 121
ai_conv_dig_sync_enable
ai_bridge_shunt_cal_shunt_cal_a_src
(nidaqmx._task_modules.timing.Timing
(nidaqmx._task_modules.channels.ai_channel.AIChannel attribute), 229
attribute), 121
ai_conv_max_rate (nidaqmx._task_modules.timing.Timing
ai_bridge_shunt_cal_shunt_cal_b_actual_resistance
attribute), 229
(nidaqmx._task_modules.channels.ai_channel.AIChannel
ai_conv_rate (nidaqmx._task_modules.timing.Timing atattribute), 121
tribute), 229
ai_bridge_shunt_cal_shunt_cal_b_resistance
ai_conv_src (nidaqmx._task_modules.timing.Timing at(nidaqmx._task_modules.channels.ai_channel.AIChannel tribute), 230
attribute), 121
ai_conv_timebase_div (nidaqmx._task_modules.timing.Timing
ai_bridge_table_electrical_vals
attribute), 230
(nidaqmx._task_modules.channels.ai_channel.AIChannel
ai_conv_timebase_src (nidaqmx._task_modules.timing.Timing
attribute), 121
attribute), 230
ai_bridge_table_physical_vals
AI_CONVERT_CLOCK (nidaqmx.constants.Signal at(nidaqmx._task_modules.channels.ai_channel.AIChannel tribute), 39
attribute), 121
ai_coupling (nidaqmx._task_modules.channels.ai_channel.AIChannel
ai_bridge_two_point_lin_first_electrical_val
attribute), 122
(nidaqmx._task_modules.channels.ai_channel.AIChannel
ai_couplings (nidaqmx.system.device.Device attribute),
attribute), 122
99
ai_bridge_two_point_lin_first_physical_val
ai_current_acrms_units (nidaqmx._task_modules.channels.ai_channel.AICh
(nidaqmx._task_modules.channels.ai_channel.AIChannel attribute), 122
attribute), 122
ai_current_int_excit_discrete_vals
ai_bridge_two_point_lin_second_electrical_val
(nidaqmx.system.device.Device
attribute),
(nidaqmx._task_modules.channels.ai_channel.AIChannel 99
attribute), 122
ai_current_rngs (nidaqmx.system.device.Device atai_bridge_two_point_lin_second_physical_val
tribute), 99
(nidaqmx._task_modules.channels.ai_channel.AIChannel
ai_current_shunt_loc (nidaqmx._task_modules.channels.ai_channel.AIChan
attribute), 122
attribute), 122
ai_bridge_units (nidaqmx._task_modules.channels.ai_channel.AIChannel
ai_current_shunt_resistance
attribute), 122
(nidaqmx._task_modules.channels.ai_channel.AIChannel
ai_channels (nidaqmx.task.Task attribute), 112
attribute), 122
ai_charge_rngs
(nidaqmx.system.device.Device
at- ai_current_units (nidaqmx._task_modules.channels.ai_channel.AIChannel
tribute), 99
attribute), 122
ai_charge_units (nidaqmx._task_modules.channels.ai_channel.AIChannel
ai_custom_scale (nidaqmx._task_modules.channels.ai_channel.AIChannel
attribute), 122
attribute), 122
ai_conv_active_edge (nidaqmx._task_modules.timing.Timing
ai_data_xfer_custom_threshold
attribute), 229
(nidaqmx._task_modules.channels.ai_channel.AIChannel
ai_conv_clk_output_term
attribute), 122
(nidaqmx._task_modules.export_signals.ExportSignals
ai_data_xfer_mech (nidaqmx._task_modules.channels.ai_channel.AIChanne
attribute), 217
attribute), 122
ai_conv_clk_pulse_polarity
ai_data_xfer_req_cond (nidaqmx._task_modules.channels.ai_channel.AICh
(nidaqmx._task_modules.export_signals.ExportSignals
attribute), 122
attribute), 217
ai_dc_offset (nidaqmx._task_modules.channels.ai_channel.AIChannel
ai_conv_dig_fltr_enable (nidaqmx._task_modules.timing.Timing
attribute), 123
attribute), 229
ai_dev_scaling_coeff (nidaqmx._task_modules.channels.ai_channel.AIChan
ai_conv_dig_fltr_min_pulse_width
attribute), 123
(nidaqmx._task_modules.timing.Timing
ai_dig_fltr_bandpass_center_freq

Index

259

NI-DAQmx Python API Documentation, Release 0.5.0

(nidaqmx._task_modules.channels.ai_channel.AIChannel attribute), 124
attribute), 123
ai_excit_sense (nidaqmx._task_modules.channels.ai_channel.AIChannel
ai_dig_fltr_bandpass_width
attribute), 124
(nidaqmx._task_modules.channels.ai_channel.AIChannel
ai_excit_src (nidaqmx._task_modules.channels.ai_channel.AIChannel
attribute), 123
attribute), 124
ai_dig_fltr_coeff (nidaqmx._task_modules.channels.ai_channel.AIChannel
ai_excit_use_for_scaling
attribute), 123
(nidaqmx._task_modules.channels.ai_channel.AIChannel
ai_dig_fltr_enable (nidaqmx._task_modules.channels.ai_channel.AIChannel
attribute), 124
attribute), 123
ai_excit_use_multiplexed
ai_dig_fltr_highpass_cutoff_freq
(nidaqmx._task_modules.channels.ai_channel.AIChannel
(nidaqmx._task_modules.channels.ai_channel.AIChannel attribute), 124
attribute), 123
ai_excit_val (nidaqmx._task_modules.channels.ai_channel.AIChannel
ai_dig_fltr_lowpass_cutoff_freq
attribute), 124
(nidaqmx._task_modules.channels.ai_channel.AIChannel
ai_excit_voltage_or_current
attribute), 123
(nidaqmx._task_modules.channels.ai_channel.AIChannel
ai_dig_fltr_lowpass_cutoff_freq_discrete_vals
attribute), 124
(nidaqmx.system.device.Device
attribute), ai_filter_delay (nidaqmx._task_modules.channels.ai_channel.AIChannel
99
attribute), 124
ai_dig_fltr_lowpass_cutoff_freq_range_vals
ai_filter_delay_adjustment
(nidaqmx.system.device.Device
attribute),
(nidaqmx._task_modules.channels.ai_channel.AIChannel
99
attribute), 124
ai_dig_fltr_notch_center_freq
ai_filter_delay_units (nidaqmx._task_modules.channels.ai_channel.AIChan
(nidaqmx._task_modules.channels.ai_channel.AIChannel attribute), 124
attribute), 123
ai_force_iepe_sensor_sensitivity
ai_dig_fltr_notch_width (nidaqmx._task_modules.channels.ai_channel.AIChannel
(nidaqmx._task_modules.channels.ai_channel.AIChannel
attribute), 123
attribute), 124
ai_dig_fltr_order (nidaqmx._task_modules.channels.ai_channel.AIChannel
ai_force_iepe_sensor_sensitivity_units
attribute), 123
(nidaqmx._task_modules.channels.ai_channel.AIChannel
ai_dig_fltr_response (nidaqmx._task_modules.channels.ai_channel.AIChannel
attribute), 125
attribute), 123
ai_force_read_from_chan
ai_dig_fltr_type (nidaqmx._task_modules.channels.ai_channel.AIChannel
(nidaqmx._task_modules.channels.ai_channel.AIChannel
attribute), 123
attribute), 125
ai_dig_fltr_types (nidaqmx.system.device.Device at- ai_force_units (nidaqmx._task_modules.channels.ai_channel.AIChannel
tribute), 99
attribute), 125
ai_dither_enable (nidaqmx._task_modules.channels.ai_channel.AIChannel
ai_freq_hyst (nidaqmx._task_modules.channels.ai_channel.AIChannel
attribute), 123
attribute), 125
ai_eddy_current_prox_sensitivity
ai_freq_rngs (nidaqmx.system.device.Device attribute),
(nidaqmx._task_modules.channels.ai_channel.AIChannel 99
attribute), 123
ai_freq_thresh_voltage (nidaqmx._task_modules.channels.ai_channel.AICh
ai_eddy_current_prox_sensitivity_units
attribute), 125
(nidaqmx._task_modules.channels.ai_channel.AIChannel
ai_freq_units (nidaqmx._task_modules.channels.ai_channel.AIChannel
attribute), 123
attribute), 125
ai_eddy_current_prox_units
ai_gain (nidaqmx._task_modules.channels.ai_channel.AIChannel
(nidaqmx._task_modules.channels.ai_channel.AIChannel attribute), 125
attribute), 123
ai_gains (nidaqmx.system.device.Device attribute), 100
ai_enhanced_alias_rejection_enable
AI_HOLD_CMPLT_EVENT (nidaqmx.constants.Signal
(nidaqmx._task_modules.channels.ai_channel.AIChannel attribute), 39
attribute), 124
ai_hold_cmplt_event_output_term
ai_excit_actual_val (nidaqmx._task_modules.channels.ai_channel.AIChannel
(nidaqmx._task_modules.export_signals.ExportSignals
attribute), 124
attribute), 217
ai_excit_d_cor_ac (nidaqmx._task_modules.channels.ai_channel.AIChannel
ai_hold_cmplt_event_pulse_polarity
attribute), 124
(nidaqmx._task_modules.export_signals.ExportSignals
ai_excit_idle_output_behavior
attribute), 217
(nidaqmx._task_modules.channels.ai_channel.AIChannel
ai_impedance (nidaqmx._task_modules.channels.ai_channel.AIChannel

260

Index

NI-DAQmx Python API Documentation, Release 0.5.0

attribute), 125
(nidaqmx._task_modules.channels.ai_channel.AIChannel
ai_input_src (nidaqmx._task_modules.channels.ai_channel.AIChannelattribute), 126
attribute), 125
ai_min (nidaqmx._task_modules.channels.ai_channel.AIChannel
ai_input_srcs (nidaqmx.system.physical_channel.PhysicalChannel attribute), 126
attribute), 104
ai_min_rate (nidaqmx.system.device.Device attribute),
ai_lead_wire_resistance (nidaqmx._task_modules.channels.ai_channel.AIChannel
100
attribute), 125
ai_open_chan_detect_enable
ai_lossy_lsb_removal_compressed_samp_size
(nidaqmx._task_modules.channels.ai_channel.AIChannel
(nidaqmx._task_modules.channels.ai_channel.AIChannel attribute), 126
attribute), 125
ai_open_thrmcpl_detect_enable
ai_lowpass_cutoff_freq (nidaqmx._task_modules.channels.ai_channel.AIChannel
(nidaqmx._task_modules.channels.ai_channel.AIChannel
attribute), 125
attribute), 126
ai_lowpass_cutoff_freq_discrete_vals
ai_physical_chans
(nidaqmx.system.device.Device
(nidaqmx.system.device.Device
attribute),
attribute), 100
100
ai_pressure_units (nidaqmx._task_modules.channels.ai_channel.AIChannel
ai_lowpass_cutoff_freq_range_vals
attribute), 127
(nidaqmx.system.device.Device
attribute), ai_probe_atten (nidaqmx._task_modules.channels.ai_channel.AIChannel
100
attribute), 127
ai_lowpass_enable (nidaqmx._task_modules.channels.ai_channel.AIChannel
ai_raw_data_compression_type
attribute), 125
(nidaqmx._task_modules.channels.ai_channel.AIChannel
ai_lowpass_switch_cap_clk_src
attribute), 127
(nidaqmx._task_modules.channels.ai_channel.AIChannel
ai_raw_samp_justification
attribute), 125
(nidaqmx._task_modules.channels.ai_channel.AIChannel
ai_lowpass_switch_cap_ext_clk_div
attribute), 127
(nidaqmx._task_modules.channels.ai_channel.AIChannel
ai_raw_samp_size (nidaqmx._task_modules.channels.ai_channel.AIChanne
attribute), 125
attribute), 127
ai_lowpass_switch_cap_ext_clk_freq
ai_remove_filter_delay (nidaqmx._task_modules.channels.ai_channel.AICh
(nidaqmx._task_modules.channels.ai_channel.AIChannel attribute), 127
attribute), 126
ai_resistance_cfg (nidaqmx._task_modules.channels.ai_channel.AIChannel
ai_lowpass_switch_cap_out_clk_div
attribute), 127
(nidaqmx._task_modules.channels.ai_channel.AIChannel
ai_resistance_rngs (nidaqmx.system.device.Device atattribute), 126
tribute), 100
ai_lvdt_sensitivity (nidaqmx._task_modules.channels.ai_channel.AIChannel
ai_resistance_units (nidaqmx._task_modules.channels.ai_channel.AIChanne
attribute), 126
attribute), 127
ai_lvdt_sensitivity_units (nidaqmx._task_modules.channels.ai_channel.AIChannel
ai_resolution (nidaqmx._task_modules.channels.ai_channel.AIChannel
attribute), 126
attribute), 127
ai_lvdt_units (nidaqmx._task_modules.channels.ai_channel.AIChannel
ai_resolution_units (nidaqmx._task_modules.channels.ai_channel.AIChanne
attribute), 126
attribute), 127
ai_max (nidaqmx._task_modules.channels.ai_channel.AIChannel
ai_rng_high (nidaqmx._task_modules.channels.ai_channel.AIChannel
attribute), 126
attribute), 127
ai_max_multi_chan_rate (nidaqmx.system.device.Device ai_rng_low (nidaqmx._task_modules.channels.ai_channel.AIChannel
attribute), 100
attribute), 127
ai_max_single_chan_rate
ai_rosette_strain_gage_gage_orientation
(nidaqmx.system.device.Device
attribute),
(nidaqmx._task_modules.channels.ai_channel.AIChannel
100
attribute), 127
ai_meas_type (nidaqmx._task_modules.channels.ai_channel.AIChannel
ai_rosette_strain_gage_rosette_meas_type
attribute), 126
(nidaqmx._task_modules.channels.ai_channel.AIChannel
ai_meas_types (nidaqmx.system.device.Device attribute),
attribute), 127
100
ai_rosette_strain_gage_rosette_type
ai_meas_types (nidaqmx.system.physical_channel.PhysicalChannel (nidaqmx._task_modules.channels.ai_channel.AIChannel
attribute), 104
attribute), 127
ai_mem_map_enable (nidaqmx._task_modules.channels.ai_channel.AIChannel
ai_rosette_strain_gage_strain_chans
attribute), 126
(nidaqmx._task_modules.channels.ai_channel.AIChannel
ai_microphone_sensitivity
attribute), 127

Index

261

NI-DAQmx Python API Documentation, Release 0.5.0

ai_rtd_a (nidaqmx._task_modules.channels.ai_channel.AIChannel attribute), 105
attribute), 127
ai_thrmcpl_cjc_chan (nidaqmx._task_modules.channels.ai_channel.AIChan
ai_rtd_b (nidaqmx._task_modules.channels.ai_channel.AIChannel attribute), 129
attribute), 128
ai_thrmcpl_cjc_src (nidaqmx._task_modules.channels.ai_channel.AIChanne
ai_rtd_c (nidaqmx._task_modules.channels.ai_channel.AIChannel attribute), 129
attribute), 128
ai_thrmcpl_cjc_val (nidaqmx._task_modules.channels.ai_channel.AIChann
ai_rtd_r_0 (nidaqmx._task_modules.channels.ai_channel.AIChannel attribute), 129
attribute), 128
ai_thrmcpl_lead_offset_voltage
ai_rtd_type (nidaqmx._task_modules.channels.ai_channel.AIChannel (nidaqmx._task_modules.channels.ai_channel.AIChannel
attribute), 128
attribute), 129
ai_rvdt_sensitivity (nidaqmx._task_modules.channels.ai_channel.AIChannel
ai_thrmcpl_scale_type (nidaqmx._task_modules.channels.ai_channel.AICha
attribute), 128
attribute), 129
ai_rvdt_sensitivity_units (nidaqmx._task_modules.channels.ai_channel.AIChannel
ai_thrmcpl_type (nidaqmx._task_modules.channels.ai_channel.AIChannel
attribute), 128
attribute), 129
ai_rvdt_units (nidaqmx._task_modules.channels.ai_channel.AIChannel
ai_thrmstr_a (nidaqmx._task_modules.channels.ai_channel.AIChannel
attribute), 128
attribute), 129
ai_samp_and_hold_enable
ai_thrmstr_b (nidaqmx._task_modules.channels.ai_channel.AIChannel
(nidaqmx._task_modules.channels.ai_channel.AIChannel attribute), 129
attribute), 128
ai_thrmstr_c (nidaqmx._task_modules.channels.ai_channel.AIChannel
ai_samp_modes (nidaqmx.system.device.Device atattribute), 129
tribute), 100
ai_thrmstr_r_1 (nidaqmx._task_modules.channels.ai_channel.AIChannel
ai_simultaneous_sampling_supported
attribute), 129
(nidaqmx.system.device.Device
attribute), ai_torque_units (nidaqmx._task_modules.channels.ai_channel.AIChannel
100
attribute), 129
ai_sound_pressure_max_sound_pressure_lvl
ai_trig_usage (nidaqmx.system.device.Device attribute),
(nidaqmx._task_modules.channels.ai_channel.AIChannel 100
attribute), 128
ai_usb_xfer_req_count (nidaqmx._task_modules.channels.ai_channel.AICh
ai_sound_pressure_units (nidaqmx._task_modules.channels.ai_channel.AIChannel
attribute), 130
attribute), 128
ai_usb_xfer_req_size (nidaqmx._task_modules.channels.ai_channel.AIChan
ai_sound_pressured_b_ref
attribute), 130
(nidaqmx._task_modules.channels.ai_channel.AIChannel
ai_velocity_iepe_sensor_sensitivity
attribute), 128
(nidaqmx._task_modules.channels.ai_channel.AIChannel
ai_strain_force_read_from_chan
attribute), 130
(nidaqmx._task_modules.channels.ai_channel.AIChannel
ai_velocity_iepe_sensor_sensitivity_units
attribute), 128
(nidaqmx._task_modules.channels.ai_channel.AIChannel
ai_strain_gage_cfg (nidaqmx._task_modules.channels.ai_channel.AIChannel
attribute), 130
attribute), 128
ai_velocity_iepe_sensord_b_ref
ai_strain_gage_gage_factor
(nidaqmx._task_modules.channels.ai_channel.AIChannel
(nidaqmx._task_modules.channels.ai_channel.AIChannel attribute), 130
attribute), 128
ai_velocity_units (nidaqmx._task_modules.channels.ai_channel.AIChannel
ai_strain_gage_poisson_ratio
attribute), 130
(nidaqmx._task_modules.channels.ai_channel.AIChannel
ai_voltage_acrms_units (nidaqmx._task_modules.channels.ai_channel.AICh
attribute), 128
attribute), 130
ai_strain_units (nidaqmx._task_modules.channels.ai_channel.AIChannel
ai_voltage_int_excit_discrete_vals
attribute), 129
(nidaqmx.system.device.Device
attribute),
ai_teds_is_teds (nidaqmx._task_modules.channels.ai_channel.AIChannel
100
attribute), 129
ai_voltage_int_excit_range_vals
ai_teds_units (nidaqmx._task_modules.channels.ai_channel.AIChannel
(nidaqmx.system.device.Device
attribute),
attribute), 129
100
ai_temp_units (nidaqmx._task_modules.channels.ai_channel.AIChannel
ai_voltage_rngs (nidaqmx.system.device.Device atattribute), 129
tribute), 101
ai_term_cfg (nidaqmx._task_modules.channels.ai_channel.AIChannel
ai_voltage_units (nidaqmx._task_modules.channels.ai_channel.AIChannel
attribute), 129
attribute), 130
ai_term_cfgs (nidaqmx.system.physical_channel.PhysicalChannel
ai_voltaged_b_ref (nidaqmx._task_modules.channels.ai_channel.AIChanne

262

Index

NI-DAQmx Python API Documentation, Release 0.5.0

attribute), 130
tribute), 44
AIChannel (class in nidaqmx._task_modules.channels.ai_channel),
ANALOG_INPUT (nidaqmx.constants.ChannelType at119
tribute), 22
AIChannelCollection
(class
in ANALOG_LEVEL (nidaqmx.constants.TriggerType atnidaqmx._task_modules.ai_channel_collection),
tribute), 44
156
ANALOG_OUTPUT (nidaqmx.constants.ChannelType
AIPhysicalChannelCollection
(class
in
attribute), 22
nidaqmx.system._collections.physical_channel_collection),
ANALOG_WINDOW (nidaqmx.constants.TriggerType
97
attribute), 44
all (nidaqmx._task_modules.ai_channel_collection.AIChannelCollection
AnalogMultiChannelReader
(class
in
attribute), 201
nidaqmx.stream_readers), 57
all (nidaqmx._task_modules.ao_channel_collection.AOChannelCollection
AnalogMultiChannelWriter
(class
in
attribute), 202
nidaqmx.stream_writers), 78
all (nidaqmx._task_modules.channel_collection.ChannelCollection
AnalogSingleChannelReader
(class
in
attribute), 156
nidaqmx.stream_readers), 56
all (nidaqmx._task_modules.ci_channel_collection.CIChannelCollection
AnalogSingleChannelWriter
(class
in
attribute), 213
nidaqmx.stream_writers), 77
all (nidaqmx._task_modules.co_channel_collection.COChannelCollection
AnalogUnscaledReader
(class
in
attribute), 215
nidaqmx.stream_readers), 59
all (nidaqmx._task_modules.di_channel_collection.DIChannelCollection
AnalogUnscaledWriter
(class
in
attribute), 215
nidaqmx.stream_writers), 79
all (nidaqmx._task_modules.do_channel_collection.DOChannelCollection
AngleUnits (class in nidaqmx.constants), 19
attribute), 216
AngularVelocityUnits (class in nidaqmx.constants), 19
all (nidaqmx.system._collections.physical_channel_collection.PhysicalChannelCollection
anlg_edge_coupling (nidaqmx._task_modules.triggering.reference_trigger.R
attribute), 98
attribute), 240
allow_interactive_deletion
anlg_edge_coupling (nidaqmx._task_modules.triggering.start_trigger.StartT
(nidaqmx.system.storage.persisted_channel.PersistedChannel
attribute), 244
attribute), 107
anlg_edge_dig_fltr_enable
allow_interactive_deletion
(nidaqmx._task_modules.triggering.reference_trigger.ReferenceT
(nidaqmx.system.storage.persisted_scale.PersistedScale
attribute), 240
attribute), 108
anlg_edge_dig_fltr_enable
allow_interactive_deletion
(nidaqmx._task_modules.triggering.start_trigger.StartTrigger
(nidaqmx.system.storage.persisted_task.PersistedTask
attribute), 244
attribute), 108
anlg_edge_dig_fltr_min_pulse_width
allow_interactive_editing
(nidaqmx._task_modules.triggering.reference_trigger.ReferenceT
(nidaqmx.system.storage.persisted_channel.PersistedChannel
attribute), 240
attribute), 107
anlg_edge_dig_fltr_min_pulse_width
allow_interactive_editing
(nidaqmx._task_modules.triggering.start_trigger.StartTrigger
(nidaqmx.system.storage.persisted_scale.PersistedScale
attribute), 244
attribute), 108
anlg_edge_dig_fltr_timebase_rate
allow_interactive_editing
(nidaqmx._task_modules.triggering.reference_trigger.ReferenceT
(nidaqmx.system.storage.persisted_task.PersistedTask
attribute), 240
attribute), 108
anlg_edge_dig_fltr_timebase_rate
ALLOW_REGENERATION
(nidaqmx._task_modules.triggering.start_trigger.StartTrigger
(nidaqmx.constants.RegenerationMode
atattribute), 244
tribute), 36
anlg_edge_dig_fltr_timebase_src
ALOW_BHIGH (nidaqmx.constants.EncoderZIndexPhase
(nidaqmx._task_modules.triggering.reference_trigger.ReferenceT
attribute), 26
attribute), 240
ALOW_BLOW (nidaqmx.constants.EncoderZIndexPhase anlg_edge_dig_fltr_timebase_src
attribute), 26
(nidaqmx._task_modules.triggering.start_trigger.StartTrigger
AM (nidaqmx.constants.ModulationType attribute), 32
attribute), 244
AMPS (nidaqmx.constants.CurrentUnits attribute), 24
anlg_edge_dig_sync_enable
AMPS (nidaqmx.constants.UnitsPreScaled attribute), 45
(nidaqmx._task_modules.triggering.reference_trigger.ReferenceT
ANALOG_EDGE (nidaqmx.constants.TriggerType atattribute), 240

Index

263

NI-DAQmx Python API Documentation, Release 0.5.0

anlg_edge_dig_sync_enable
attribute), 240
(nidaqmx._task_modules.triggering.start_trigger.StartTrigger
anlg_win_coupling (nidaqmx._task_modules.triggering.start_trigger.StartTr
attribute), 244
attribute), 245
anlg_edge_hyst (nidaqmx._task_modules.triggering.reference_trigger.ReferenceTrigger
anlg_win_dig_fltr_enable
attribute), 240
(nidaqmx._task_modules.triggering.pause_trigger.PauseTrigger
anlg_edge_hyst (nidaqmx._task_modules.triggering.start_trigger.StartTrigger
attribute), 238
attribute), 244
anlg_win_dig_fltr_enable
anlg_edge_lvl (nidaqmx._task_modules.triggering.reference_trigger.ReferenceTrigger
(nidaqmx._task_modules.triggering.reference_trigger.ReferenceT
attribute), 240
attribute), 241
anlg_edge_lvl (nidaqmx._task_modules.triggering.start_trigger.StartTrigger
anlg_win_dig_fltr_enable
attribute), 244
(nidaqmx._task_modules.triggering.start_trigger.StartTrigger
anlg_edge_slope (nidaqmx._task_modules.triggering.reference_trigger.ReferenceTrigger
attribute), 245
attribute), 240
anlg_win_dig_fltr_min_pulse_width
anlg_edge_slope (nidaqmx._task_modules.triggering.start_trigger.StartTrigger
(nidaqmx._task_modules.triggering.pause_trigger.PauseTrigger
attribute), 244
attribute), 238
anlg_edge_src (nidaqmx._task_modules.triggering.reference_trigger.ReferenceTrigger
anlg_win_dig_fltr_min_pulse_width
attribute), 240
(nidaqmx._task_modules.triggering.reference_trigger.ReferenceT
anlg_edge_src (nidaqmx._task_modules.triggering.start_trigger.StartTrigger
attribute), 241
attribute), 244
anlg_win_dig_fltr_min_pulse_width
anlg_lvl_coupling (nidaqmx._task_modules.triggering.pause_trigger.PauseTrigger
(nidaqmx._task_modules.triggering.start_trigger.StartTrigger
attribute), 237
attribute), 245
anlg_lvl_dig_fltr_enable (nidaqmx._task_modules.triggering.pause_trigger.PauseTrigger
anlg_win_dig_fltr_timebase_rate
attribute), 238
(nidaqmx._task_modules.triggering.pause_trigger.PauseTrigger
anlg_lvl_dig_fltr_min_pulse_width
attribute), 238
(nidaqmx._task_modules.triggering.pause_trigger.PauseTrigger
anlg_win_dig_fltr_timebase_rate
attribute), 238
(nidaqmx._task_modules.triggering.reference_trigger.ReferenceT
anlg_lvl_dig_fltr_timebase_rate
attribute), 241
(nidaqmx._task_modules.triggering.pause_trigger.PauseTrigger
anlg_win_dig_fltr_timebase_rate
attribute), 238
(nidaqmx._task_modules.triggering.start_trigger.StartTrigger
anlg_lvl_dig_fltr_timebase_src
attribute), 245
(nidaqmx._task_modules.triggering.pause_trigger.PauseTrigger
anlg_win_dig_fltr_timebase_src
attribute), 238
(nidaqmx._task_modules.triggering.pause_trigger.PauseTrigger
anlg_lvl_dig_sync_enable
attribute), 239
(nidaqmx._task_modules.triggering.pause_trigger.PauseTrigger
anlg_win_dig_fltr_timebase_src
attribute), 238
(nidaqmx._task_modules.triggering.reference_trigger.ReferenceT
anlg_lvl_hyst (nidaqmx._task_modules.triggering.pause_trigger.PauseTrigger
attribute), 241
attribute), 238
anlg_win_dig_fltr_timebase_src
anlg_lvl_lvl (nidaqmx._task_modules.triggering.pause_trigger.PauseTrigger
(nidaqmx._task_modules.triggering.start_trigger.StartTrigger
attribute), 238
attribute), 245
anlg_lvl_src (nidaqmx._task_modules.triggering.pause_trigger.PauseTrigger
anlg_win_dig_sync_enable
attribute), 238
(nidaqmx._task_modules.triggering.pause_trigger.PauseTrigger
anlg_lvl_when (nidaqmx._task_modules.triggering.pause_trigger.PauseTrigger
attribute), 239
attribute), 238
anlg_win_dig_sync_enable
anlg_trig_supported (nidaqmx.system.device.Device at(nidaqmx._task_modules.triggering.reference_trigger.ReferenceT
tribute), 101
attribute), 241
anlg_win_btm (nidaqmx._task_modules.triggering.pause_trigger.PauseTrigger
anlg_win_dig_sync_enable
attribute), 238
(nidaqmx._task_modules.triggering.start_trigger.StartTrigger
anlg_win_btm (nidaqmx._task_modules.triggering.reference_trigger.ReferenceTrigger
attribute), 245
attribute), 240
anlg_win_src (nidaqmx._task_modules.triggering.pause_trigger.PauseTrigg
anlg_win_btm (nidaqmx._task_modules.triggering.start_trigger.StartTrigger
attribute), 239
attribute), 245
anlg_win_src (nidaqmx._task_modules.triggering.reference_trigger.Referen
anlg_win_coupling (nidaqmx._task_modules.triggering.pause_trigger.PauseTrigger
attribute), 241
attribute), 238
anlg_win_src (nidaqmx._task_modules.triggering.start_trigger.StartTrigger
anlg_win_coupling (nidaqmx._task_modules.triggering.reference_trigger.ReferenceTrigger
attribute), 245

264

Index

NI-DAQmx Python API Documentation, Release 0.5.0

anlg_win_top (nidaqmx._task_modules.triggering.pause_trigger.PauseTrigger
attribute), 132
attribute), 239
ao_filter_delay_units (nidaqmx._task_modules.channels.ao_channel.AOCha
anlg_win_top (nidaqmx._task_modules.triggering.reference_trigger.ReferenceTrigger
attribute), 132
attribute), 241
ao_func_gen_amplitude (nidaqmx._task_modules.channels.ao_channel.AOC
anlg_win_top (nidaqmx._task_modules.triggering.start_trigger.StartTrigger
attribute), 132
attribute), 245
ao_func_gen_fm_deviation
anlg_win_trig_when (nidaqmx._task_modules.triggering.reference_trigger.ReferenceTrigger
(nidaqmx._task_modules.channels.ao_channel.AOChannel
attribute), 241
attribute), 132
anlg_win_trig_when (nidaqmx._task_modules.triggering.start_trigger.StartTrigger
ao_func_gen_freq (nidaqmx._task_modules.channels.ao_channel.AOChann
attribute), 245
attribute), 132
anlg_win_when (nidaqmx._task_modules.triggering.pause_trigger.PauseTrigger
ao_func_gen_modulation_type
attribute), 239
(nidaqmx._task_modules.channels.ao_channel.AOChannel
ao_channels (nidaqmx.task.Task attribute), 112
attribute), 132
ao_current_rngs (nidaqmx.system.device.Device at- ao_func_gen_offset (nidaqmx._task_modules.channels.ao_channel.AOChan
tribute), 101
attribute), 133
ao_current_units (nidaqmx._task_modules.channels.ao_channel.AOChannel
ao_func_gen_square_duty_cycle
attribute), 131
(nidaqmx._task_modules.channels.ao_channel.AOChannel
ao_custom_scale (nidaqmx._task_modules.channels.ao_channel.AOChannel
attribute), 133
attribute), 131
ao_func_gen_type (nidaqmx._task_modules.channels.ao_channel.AOChann
ao_dac_offset_ext_src (nidaqmx._task_modules.channels.ao_channel.AOChannel
attribute), 133
attribute), 131
ao_gain (nidaqmx._task_modules.channels.ao_channel.AOChannel
ao_dac_offset_src (nidaqmx._task_modules.channels.ao_channel.AOChannel
attribute), 133
attribute), 131
ao_gains (nidaqmx.system.device.Device attribute), 101
ao_dac_offset_val (nidaqmx._task_modules.channels.ao_channel.AOChannel
ao_idle_output_behavior
attribute), 131
(nidaqmx._task_modules.channels.ao_channel.AOChannel
ao_dac_ref_allow_conn_to_gnd
attribute), 133
(nidaqmx._task_modules.channels.ao_channel.AOChannel
ao_load_impedance (nidaqmx._task_modules.channels.ao_channel.AOChan
attribute), 131
attribute), 133
ao_dac_ref_conn_to_gnd
ao_manual_control_amplitude
(nidaqmx._task_modules.channels.ao_channel.AOChannel (nidaqmx.system.physical_channel.PhysicalChannel
attribute), 131
attribute), 105
ao_dac_ref_ext_src (nidaqmx._task_modules.channels.ao_channel.AOChannel
ao_manual_control_enable
attribute), 131
(nidaqmx.system.physical_channel.PhysicalChannel
ao_dac_ref_src (nidaqmx._task_modules.channels.ao_channel.AOChannel
attribute), 105
attribute), 132
ao_manual_control_freq (nidaqmx.system.physical_channel.PhysicalChann
ao_dac_ref_val (nidaqmx._task_modules.channels.ao_channel.AOChannel
attribute), 105
attribute), 132
ao_manual_control_short_detected
ao_dac_rng_high (nidaqmx._task_modules.channels.ao_channel.AOChannel
(nidaqmx.system.physical_channel.PhysicalChannel
attribute), 132
attribute), 105
ao_dac_rng_low (nidaqmx._task_modules.channels.ao_channel.AOChannel
ao_max (nidaqmx._task_modules.channels.ao_channel.AOChannel
attribute), 132
attribute), 133
ao_data_xfer_mech (nidaqmx._task_modules.channels.ao_channel.AOChannel
ao_max_rate (nidaqmx.system.device.Device attribute),
attribute), 132
101
ao_data_xfer_req_cond (nidaqmx._task_modules.channels.ao_channel.AOChannel
ao_mem_map_enable (nidaqmx._task_modules.channels.ao_channel.AOCh
attribute), 132
attribute), 133
ao_dev_scaling_coeff (nidaqmx._task_modules.channels.ao_channel.AOChannel
ao_min (nidaqmx._task_modules.channels.ao_channel.AOChannel
attribute), 132
attribute), 133
ao_enhanced_image_rejection_enable
ao_min_rate (nidaqmx.system.device.Device attribute),
(nidaqmx._task_modules.channels.ao_channel.AOChannel 101
attribute), 132
ao_output_impedance (nidaqmx._task_modules.channels.ao_channel.AOCh
ao_filter_delay (nidaqmx._task_modules.channels.ao_channel.AOChannel
attribute), 133
attribute), 132
ao_output_type (nidaqmx._task_modules.channels.ao_channel.AOChannel
ao_filter_delay_adjustment
attribute), 133
(nidaqmx._task_modules.channels.ao_channel.AOChannel
ao_output_types (nidaqmx.system.device.Device at-

Index

265

NI-DAQmx Python API Documentation, Release 0.5.0

tribute), 101
131
ao_output_types (nidaqmx.system.physical_channel.PhysicalChannel
AOChannelCollection
(class
in
attribute), 105
nidaqmx._task_modules.ao_channel_collection),
ao_physical_chans (nidaqmx.system.device.Device at201
tribute), 101
AOExpirationState (class in nidaqmx.types), 247
ao_power_amp_channel_enable
AOIdleOutputBehavior (class in nidaqmx.constants), 18
(nidaqmx.system.physical_channel.PhysicalChannel
AOPhysicalChannelCollection
(class
in
attribute), 105
nidaqmx.system._collections.physical_channel_collection),
ao_power_amp_gain (nidaqmx.system.physical_channel.PhysicalChannel
97
attribute), 105
AOPowerUpOutputBehavior
(class
in
ao_power_amp_offset (nidaqmx.system.physical_channel.PhysicalChannel
nidaqmx.constants), 18
attribute), 105
AOPowerUpState (class in nidaqmx.types), 248
ao_power_amp_overcurrent
are_configured_cdaq_sync_ports_disconnected()
(nidaqmx.system.physical_channel.PhysicalChannel
(nidaqmx.system.system.System
method),
attribute), 105
91
ao_power_amp_scaling_coeff
ARM_START (nidaqmx.constants.TriggerUsage at(nidaqmx.system.physical_channel.PhysicalChannel
tribute), 44
attribute), 105
arm_start_trigger (nidaqmx._task_modules.triggers.Triggers
ao_power_up_output_types
attribute), 236
(nidaqmx.system.physical_channel.PhysicalChannel
ArmStartTrigger
(class
in
attribute), 105
nidaqmx._task_modules.triggering.arm_start_trigger),
ao_reglitch_enable (nidaqmx._task_modules.channels.ao_channel.AOChannel
236
attribute), 133
AUSE_UNTIL_DATA_AVAILABLE
ao_resolution (nidaqmx._task_modules.channels.ao_channel.AOChannel
(nidaqmx.constants.UnderflowBehavior
atattribute), 133
tribute), 45
ao_resolution_units (nidaqmx._task_modules.channels.ao_channel.AOChannel
author (nidaqmx.system.storage.persisted_channel.PersistedChannel
attribute), 133
attribute), 107
ao_samp_clk_supported (nidaqmx.system.device.Device author (nidaqmx.system.storage.persisted_scale.PersistedScale
attribute), 101
attribute), 108
ao_samp_modes (nidaqmx.system.device.Device at- author (nidaqmx.system.storage.persisted_task.PersistedTask
tribute), 101
attribute), 108
AO_SERIES
(nidaqmx.constants.ProductCategory auto_configure_cdaq_sync_connections()
attribute), 34
(nidaqmx.system.system.System
method),
ao_term_cfg (nidaqmx._task_modules.channels.ao_channel.AOChannel
92
attribute), 134
auto_start (nidaqmx._task_modules.in_stream.InStream
ao_term_cfgs (nidaqmx.system.physical_channel.PhysicalChannel attribute), 220
attribute), 105
auto_start (nidaqmx._task_modules.out_stream.OutStream
ao_trig_usage (nidaqmx.system.device.Device attribute),
attribute), 226
101
auto_start (nidaqmx.stream_writers.AnalogMultiChannelWriter
ao_usb_xfer_req_count (nidaqmx._task_modules.channels.ao_channel.AOChannel
attribute), 78
attribute), 134
auto_start (nidaqmx.stream_writers.AnalogSingleChannelWriter
ao_usb_xfer_req_size (nidaqmx._task_modules.channels.ao_channel.AOChannel
attribute), 77
attribute), 134
auto_start (nidaqmx.stream_writers.AnalogUnscaledWriter
ao_use_only_on_brd_mem
attribute), 79
(nidaqmx._task_modules.channels.ao_channel.AOChannel
auto_start
(nidaqmx.stream_writers.CounterWriter
attribute), 134
attribute), 82
ao_voltage_current_limit
auto_start (nidaqmx.stream_writers.DigitalMultiChannelWriter
(nidaqmx._task_modules.channels.ao_channel.AOChannel attribute), 87
attribute), 134
auto_start (nidaqmx.stream_writers.DigitalSingleChannelWriter
ao_voltage_rngs (nidaqmx.system.device.Device atattribute), 84
tribute), 101
auto_trig_enable (nidaqmx._task_modules.triggering.reference_trigger.Refe
ao_voltage_units (nidaqmx._task_modules.channels.ao_channel.AOChannel
attribute), 241
attribute), 134
auto_triggered (nidaqmx._task_modules.triggering.reference_trigger.Refere
AOChannel (class in nidaqmx._task_modules.channels.ao_channel), attribute), 241

266

Index

NI-DAQmx Python API Documentation, Release 0.5.0

AUTOMATIC (nidaqmx.constants.ADCTimingMode at- carrier_serial_num (nidaqmx.system.device.Device attribute), 17
tribute), 101
AutoZeroType (class in nidaqmx.constants), 20
CARTESIAN_SHEAR_STRAIN_XY
avail_samp_per_chan (nidaqmx._task_modules.in_stream.InStream (nidaqmx.constants.StrainGageRosetteMeasurementType
attribute), 220
attribute), 41
CARTESIAN_STRAIN_X
B
(nidaqmx.constants.StrainGageRosetteMeasurementType
attribute), 41
B (nidaqmx.constants.ShuntCalSelect attribute), 39
CARTESIAN_STRAIN_Y
B (nidaqmx.constants.ShuntResistorSelect attribute), 39
(nidaqmx.constants.StrainGageRosetteMeasurementType
B (nidaqmx.constants.ThermocoupleType attribute), 43
attribute), 41
B_SERIES_DAQ (nidaqmx.constants.ProductCategory
CDAQSyncConnection (class in nidaqmx.types), 248
attribute), 34
BANDPASS (nidaqmx.constants.FilterType attribute), 28 cfg_anlg_edge_ref_trig()
(nidaqmx._task_modules.triggering.reference_trigger.ReferenceT
BAR (nidaqmx.constants.BridgePhysicalUnits attribute),
method), 241
20
cfg_anlg_edge_start_trig()
BAR (nidaqmx.constants.PressureUnits attribute), 34
(nidaqmx._task_modules.triggering.start_trigger.StartTrigger
BAR (nidaqmx.constants.UnitsPreScaled attribute), 45
method), 245
BELOW (nidaqmx.constants.ActiveLevel attribute), 19
cfg_anlg_window_ref_trig()
BEST_50_HZ_REJECTION
(nidaqmx._task_modules.triggering.reference_trigger.ReferenceT
(nidaqmx.constants.ADCTimingMode
atmethod), 242
tribute), 17
cfg_anlg_window_start_trig()
BEST_60_HZ_REJECTION
(nidaqmx._task_modules.triggering.start_trigger.StartTrigger
(nidaqmx.constants.ADCTimingMode
atmethod), 246
tribute), 17
cfg_burst_handshaking_timing_export_clock()
BITS (nidaqmx.constants.ResolutionType attribute), 37
(nidaqmx._task_modules.timing.Timing
BREAK_BEFORE_MAKE
method), 230
(nidaqmx.constants.BreakMode
attribute),
cfg_burst_handshaking_timing_import_clock()
20
(nidaqmx._task_modules.timing.Timing
BreakMode (class in nidaqmx.constants), 20
method), 230
BRIDGE (nidaqmx.constants.UsageTypeAI attribute), 47
cfg_change_detection_timing()
BridgeConfiguration (class in nidaqmx.constants), 20
(nidaqmx._task_modules.timing.Timing
BridgeElectricalUnits (class in nidaqmx.constants), 20
method), 231
BridgePhysicalUnits (class in nidaqmx.constants), 20
cfg_dig_edge_ref_trig() (nidaqmx._task_modules.triggering.reference_trigg
BridgeShuntCalSource (class in nidaqmx.constants), 21
method), 242
BridgeUnits (class in nidaqmx.constants), 21
BUILT_IN (nidaqmx.constants.BridgeShuntCalSource cfg_dig_edge_start_trig()
(nidaqmx._task_modules.triggering.start_trigger.StartTrigger
attribute), 21
method), 246
BUILT_IN (nidaqmx.constants.CJCSource attribute), 22
cfg_dig_pattern_ref_trig()
BURST_HANDSHAKE (nidaqmx.constants.SampleTimingType
(nidaqmx._task_modules.triggering.reference_trigger.ReferenceT
attribute), 37
method), 242
bus_type (nidaqmx.system.device.Device attribute), 101
cfg_dig_pattern_start_trig()
BusType (class in nidaqmx.constants), 21
(nidaqmx._task_modules.triggering.start_trigger.StartTrigger
BUTTERWORTH (nidaqmx.constants.FilterResponse atmethod), 246
tribute), 28
cfg_handshaking_timing()
(nidaqmx._task_modules.timing.Timing
C
method), 231
C_SERIES_MODULE (nidaqmx.constants.ProductCategory
cfg_implicit_timing()
(nidaqmx._task_modules.timing.Timing
attribute), 34
method),
232
calculate_reverse_poly_coeff()
(nidaqmx.scale.Scale
cfg_pipelined_samp_clk_timing()
static method), 52
(nidaqmx._task_modules.timing.Timing
CalibrationMode2 (class in nidaqmx.constants), 22
method), 232
CalibrationTerminalConfig (class in nidaqmx.constants),
cfg_samp_clk_timing()
(nidaqmx._task_modules.timing.Timing
22
method),
232
CANCEL (nidaqmx.constants.Action attribute), 19
Index

267

NI-DAQmx Python API Documentation, Release 0.5.0

cfg_watchdog_ao_expir_states()
attribute), 33
(nidaqmx.system.watchdog.WatchdogTask
CHANNEL_HIGH_IMPEDANCE
method), 109
(nidaqmx.constants.PowerUpChannelType
cfg_watchdog_co_expir_states()
attribute), 33
(nidaqmx.system.watchdog.WatchdogTask
CHANNEL_IN_USE (nidaqmx.constants.PathCapability
method), 109
attribute), 33
cfg_watchdog_do_expir_states()
channel_names (nidaqmx._task_modules.ai_channel_collection.AIChannelC
(nidaqmx.system.watchdog.WatchdogTask
attribute), 201
method), 110
channel_names (nidaqmx._task_modules.ao_channel_collection.AOChanne
CHAN_FOR_ALL_LINES
attribute), 202
(nidaqmx.constants.LineGrouping attribute), channel_names (nidaqmx._task_modules.channel_collection.ChannelCollec
31
attribute), 156
CHAN_PER_LINE (nidaqmx.constants.LineGrouping channel_names (nidaqmx._task_modules.channels.ai_channel.AIChannel
attribute), 31
attribute), 130
chan_type (nidaqmx._task_modules.channels.ai_channel.AIChannel
channel_names (nidaqmx._task_modules.channels.ao_channel.AOChannel
attribute), 130
attribute), 134
chan_type (nidaqmx._task_modules.channels.ao_channel.AOChannel
channel_names (nidaqmx._task_modules.channels.channel.Channel
attribute), 134
attribute), 118
chan_type (nidaqmx._task_modules.channels.channel.Channel
channel_names (nidaqmx._task_modules.channels.ci_channel.CIChannel
attribute), 118
attribute), 135
chan_type (nidaqmx._task_modules.channels.ci_channel.CIChannel
channel_names (nidaqmx._task_modules.channels.co_channel.COChannel
attribute), 135
attribute), 149
chan_type (nidaqmx._task_modules.channels.co_channel.COChannel
channel_names (nidaqmx._task_modules.channels.di_channel.DIChannel
attribute), 149
attribute), 152
chan_type (nidaqmx._task_modules.channels.di_channel.DIChannel
channel_names (nidaqmx._task_modules.channels.do_channel.DOChannel
attribute), 152
attribute), 154
chan_type (nidaqmx._task_modules.channels.do_channel.DOChannel
channel_names (nidaqmx._task_modules.ci_channel_collection.CIChannelC
attribute), 154
attribute), 213
change_detect_di_falling_edge_physical_chans
channel_names (nidaqmx._task_modules.co_channel_collection.COChanne
(nidaqmx._task_modules.timing.Timing
attribute), 215
attribute), 233
channel_names (nidaqmx._task_modules.di_channel_collection.DIChannelC
change_detect_di_rising_edge_physical_chans
attribute), 215
(nidaqmx._task_modules.timing.Timing
channel_names (nidaqmx._task_modules.do_channel_collection.DOChanne
attribute), 233
attribute), 216
change_detect_di_tristate
channel_names (nidaqmx.system._collections.physical_channel_collection.P
(nidaqmx._task_modules.timing.Timing
attribute), 98
attribute), 233
channel_names (nidaqmx.task.Task attribute), 112
change_detect_event_output_term
CHANNEL_RESERVED_FOR_ROUTING
(nidaqmx._task_modules.export_signals.ExportSignals
(nidaqmx.constants.PathCapability attribute),
attribute), 217
33
change_detect_event_pulse_polarity
CHANNEL_SOURCE_CONFLICT
(nidaqmx._task_modules.export_signals.ExportSignals
(nidaqmx.constants.PathCapability attribute),
attribute), 217
33
change_detect_overflowed
channel_type
(nidaqmx.types.AOPowerUpState
at(nidaqmx._task_modules.in_stream.InStream
tribute), 248
attribute), 220
CHANNEL_VOLTAGE (nidaqmx.constants.PowerUpChannelType
CHANGE_DETECTION
attribute), 33
(nidaqmx.constants.SampleTimingType
at- ChannelCollection
(class
in
tribute), 37
nidaqmx._task_modules.channel_collection),
CHANGE_DETECTION_EVENT
156
(nidaqmx.constants.Signal attribute), 39
channels (nidaqmx.task.Task attribute), 112
Channel (class in nidaqmx._task_modules.channels.channel),channels_to_read (nidaqmx._task_modules.in_stream.InStream
118
attribute), 220
CHANNEL_CURRENT (nidaqmx.constants.PowerUpChannelType
ChannelType (class in nidaqmx.constants), 22

268

Index

NI-DAQmx Python API Documentation, Release 0.5.0

CHARGE (nidaqmx.constants.CalibrationMode2 atattribute), 136
tribute), 22
ci_count_edges_count_reset_dig_fltr_timebase_src
CHARGE (nidaqmx.constants.UsageTypeAI attribute),
(nidaqmx._task_modules.channels.ci_channel.CIChannel
47
attribute), 136
ChargeUnits (class in nidaqmx.constants), 23
ci_count_edges_count_reset_dig_sync_enable
chassis_module_devices (nidaqmx.system.device.Device
(nidaqmx._task_modules.channels.ci_channel.CIChannel
attribute), 101
attribute), 136
CHS (nidaqmx.constants.Language attribute), 30
ci_count_edges_count_reset_enable
ci_ang_encoder_initial_angle
(nidaqmx._task_modules.channels.ci_channel.CIChannel
(nidaqmx._task_modules.channels.ci_channel.CIChannel attribute), 136
attribute), 135
ci_count_edges_count_reset_logic_lvl_behavior
ci_ang_encoder_pulses_per_rev
(nidaqmx._task_modules.channels.ci_channel.CIChannel
(nidaqmx._task_modules.channels.ci_channel.CIChannel attribute), 136
attribute), 135
ci_count_edges_count_reset_reset_cnt
ci_ang_encoder_units (nidaqmx._task_modules.channels.ci_channel.CIChannel
(nidaqmx._task_modules.channels.ci_channel.CIChannel
attribute), 135
attribute), 136
ci_channels (nidaqmx.task.Task attribute), 112
ci_count_edges_count_reset_term
ci_count (nidaqmx._task_modules.channels.ci_channel.CIChannel (nidaqmx._task_modules.channels.ci_channel.CIChannel
attribute), 135
attribute), 136
ci_count_edges_active_edge
ci_count_edges_count_reset_term_cfg
(nidaqmx._task_modules.channels.ci_channel.CIChannel (nidaqmx._task_modules.channels.ci_channel.CIChannel
attribute), 135
attribute), 136
ci_count_edges_count_dir_dig_fltr_enable
ci_count_edges_dig_fltr_enable
(nidaqmx._task_modules.channels.ci_channel.CIChannel (nidaqmx._task_modules.channels.ci_channel.CIChannel
attribute), 135
attribute), 136
ci_count_edges_count_dir_dig_fltr_min_pulse_width
ci_count_edges_dig_fltr_min_pulse_width
(nidaqmx._task_modules.channels.ci_channel.CIChannel (nidaqmx._task_modules.channels.ci_channel.CIChannel
attribute), 135
attribute), 136
ci_count_edges_count_dir_dig_fltr_timebase_rate
ci_count_edges_dig_fltr_timebase_rate
(nidaqmx._task_modules.channels.ci_channel.CIChannel (nidaqmx._task_modules.channels.ci_channel.CIChannel
attribute), 135
attribute), 136
ci_count_edges_count_dir_dig_fltr_timebase_src
ci_count_edges_dig_fltr_timebase_src
(nidaqmx._task_modules.channels.ci_channel.CIChannel (nidaqmx._task_modules.channels.ci_channel.CIChannel
attribute), 135
attribute), 136
ci_count_edges_count_dir_dig_sync_enable
ci_count_edges_dig_sync_enable
(nidaqmx._task_modules.channels.ci_channel.CIChannel (nidaqmx._task_modules.channels.ci_channel.CIChannel
attribute), 135
attribute), 136
ci_count_edges_count_dir_logic_lvl_behavior
ci_count_edges_dir (nidaqmx._task_modules.channels.ci_channel.CIChann
(nidaqmx._task_modules.channels.ci_channel.CIChannel attribute), 136
attribute), 135
ci_count_edges_dir_term
ci_count_edges_count_dir_term_cfg
(nidaqmx._task_modules.channels.ci_channel.CIChannel
(nidaqmx._task_modules.channels.ci_channel.CIChannel attribute), 136
attribute), 135
ci_count_edges_gate_dig_fltr_enable
ci_count_edges_count_reset_active_edge
(nidaqmx._task_modules.channels.ci_channel.CIChannel
(nidaqmx._task_modules.channels.ci_channel.CIChannel attribute), 137
attribute), 136
ci_count_edges_gate_dig_fltr_min_pulse_width
ci_count_edges_count_reset_dig_fltr_enable
(nidaqmx._task_modules.channels.ci_channel.CIChannel
(nidaqmx._task_modules.channels.ci_channel.CIChannel attribute), 137
attribute), 136
ci_count_edges_gate_dig_fltr_timebase_rate
ci_count_edges_count_reset_dig_fltr_min_pulse_width
(nidaqmx._task_modules.channels.ci_channel.CIChannel
(nidaqmx._task_modules.channels.ci_channel.CIChannel attribute), 137
attribute), 136
ci_count_edges_gate_dig_fltr_timebase_src
ci_count_edges_count_reset_dig_fltr_timebase_rate
(nidaqmx._task_modules.channels.ci_channel.CIChannel
(nidaqmx._task_modules.channels.ci_channel.CIChannel attribute), 137

Index

269

NI-DAQmx Python API Documentation, Release 0.5.0

ci_count_edges_gate_enable
attribute), 138
(nidaqmx._task_modules.channels.ci_channel.CIChannel
ci_data_xfer_req_cond (nidaqmx._task_modules.channels.ci_channel.CICh
attribute), 137
attribute), 138
ci_count_edges_gate_logic_lvl_behavior
ci_dup_count_prevention
(nidaqmx._task_modules.channels.ci_channel.CIChannel (nidaqmx._task_modules.channels.ci_channel.CIChannel
attribute), 137
attribute), 138
ci_count_edges_gate_term
ci_duty_cycle_dig_fltr_enable
(nidaqmx._task_modules.channels.ci_channel.CIChannel (nidaqmx._task_modules.channels.ci_channel.CIChannel
attribute), 137
attribute), 138
ci_count_edges_gate_term_cfg
ci_duty_cycle_dig_fltr_min_pulse_width
(nidaqmx._task_modules.channels.ci_channel.CIChannel (nidaqmx._task_modules.channels.ci_channel.CIChannel
attribute), 137
attribute), 138
ci_count_edges_gate_when
ci_duty_cycle_dig_fltr_timebase_rate
(nidaqmx._task_modules.channels.ci_channel.CIChannel (nidaqmx._task_modules.channels.ci_channel.CIChannel
attribute), 137
attribute), 138
ci_count_edges_initial_cnt
ci_duty_cycle_dig_fltr_timebase_src
(nidaqmx._task_modules.channels.ci_channel.CIChannel (nidaqmx._task_modules.channels.ci_channel.CIChannel
attribute), 137
attribute), 138
ci_count_edges_logic_lvl_behavior
ci_duty_cycle_logic_lvl_behavior
(nidaqmx._task_modules.channels.ci_channel.CIChannel (nidaqmx._task_modules.channels.ci_channel.CIChannel
attribute), 137
attribute), 138
ci_count_edges_term (nidaqmx._task_modules.channels.ci_channel.CIChannel
ci_duty_cycle_starting_edge
attribute), 137
(nidaqmx._task_modules.channels.ci_channel.CIChannel
ci_count_edges_term_cfg
attribute), 138
(nidaqmx._task_modules.channels.ci_channel.CIChannel
ci_duty_cycle_term (nidaqmx._task_modules.channels.ci_channel.CIChann
attribute), 137
attribute), 138
ci_ctr_timebase_active_edge
ci_duty_cycle_term_cfg (nidaqmx._task_modules.channels.ci_channel.CIC
(nidaqmx._task_modules.channels.ci_channel.CIChannel attribute), 138
attribute), 137
ci_encoder_a_input_dig_fltr_enable
ci_ctr_timebase_dig_fltr_enable
(nidaqmx._task_modules.channels.ci_channel.CIChannel
(nidaqmx._task_modules.channels.ci_channel.CIChannel attribute), 138
attribute), 137
ci_encoder_a_input_dig_fltr_min_pulse_width
ci_ctr_timebase_dig_fltr_min_pulse_width
(nidaqmx._task_modules.channels.ci_channel.CIChannel
(nidaqmx._task_modules.channels.ci_channel.CIChannel attribute), 138
attribute), 137
ci_encoder_a_input_dig_fltr_timebase_rate
ci_ctr_timebase_dig_fltr_timebase_rate
(nidaqmx._task_modules.channels.ci_channel.CIChannel
(nidaqmx._task_modules.channels.ci_channel.CIChannel attribute), 139
attribute), 137
ci_encoder_a_input_dig_fltr_timebase_src
ci_ctr_timebase_dig_fltr_timebase_src
(nidaqmx._task_modules.channels.ci_channel.CIChannel
(nidaqmx._task_modules.channels.ci_channel.CIChannel attribute), 139
attribute), 137
ci_encoder_a_input_dig_sync_enable
ci_ctr_timebase_dig_sync_enable
(nidaqmx._task_modules.channels.ci_channel.CIChannel
(nidaqmx._task_modules.channels.ci_channel.CIChannel attribute), 139
attribute), 137
ci_encoder_a_input_logic_lvl_behavior
ci_ctr_timebase_master_timebase_div
(nidaqmx._task_modules.channels.ci_channel.CIChannel
(nidaqmx._task_modules.channels.ci_channel.CIChannel attribute), 139
attribute), 138
ci_encoder_a_input_term
ci_ctr_timebase_rate (nidaqmx._task_modules.channels.ci_channel.CIChannel
(nidaqmx._task_modules.channels.ci_channel.CIChannel
attribute), 138
attribute), 139
ci_ctr_timebase_src (nidaqmx._task_modules.channels.ci_channel.CIChannel
ci_encoder_a_input_term_cfg
attribute), 138
(nidaqmx._task_modules.channels.ci_channel.CIChannel
ci_custom_scale (nidaqmx._task_modules.channels.ci_channel.CIChannel
attribute), 139
attribute), 138
ci_encoder_b_input_dig_fltr_enable
ci_data_xfer_mech (nidaqmx._task_modules.channels.ci_channel.CIChannel
(nidaqmx._task_modules.channels.ci_channel.CIChannel

270

Index

NI-DAQmx Python API Documentation, Release 0.5.0

attribute), 139
ci_encoder_z_input_term_cfg
ci_encoder_b_input_dig_fltr_min_pulse_width
(nidaqmx._task_modules.channels.ci_channel.CIChannel
(nidaqmx._task_modules.channels.ci_channel.CIChannel attribute), 140
attribute), 139
ci_freq_dig_fltr_enable (nidaqmx._task_modules.channels.ci_channel.CICh
ci_encoder_b_input_dig_fltr_timebase_rate
attribute), 140
(nidaqmx._task_modules.channels.ci_channel.CIChannel
ci_freq_dig_fltr_min_pulse_width
attribute), 139
(nidaqmx._task_modules.channels.ci_channel.CIChannel
ci_encoder_b_input_dig_fltr_timebase_src
attribute), 140
(nidaqmx._task_modules.channels.ci_channel.CIChannel
ci_freq_dig_fltr_timebase_rate
attribute), 139
(nidaqmx._task_modules.channels.ci_channel.CIChannel
ci_encoder_b_input_dig_sync_enable
attribute), 140
(nidaqmx._task_modules.channels.ci_channel.CIChannel
ci_freq_dig_fltr_timebase_src
attribute), 139
(nidaqmx._task_modules.channels.ci_channel.CIChannel
ci_encoder_b_input_logic_lvl_behavior
attribute), 140
(nidaqmx._task_modules.channels.ci_channel.CIChannel
ci_freq_dig_sync_enable
attribute), 139
(nidaqmx._task_modules.channels.ci_channel.CIChannel
ci_encoder_b_input_term
attribute), 140
(nidaqmx._task_modules.channels.ci_channel.CIChannel
ci_freq_div (nidaqmx._task_modules.channels.ci_channel.CIChannel
attribute), 139
attribute), 140
ci_encoder_b_input_term_cfg
ci_freq_enable_averaging
(nidaqmx._task_modules.channels.ci_channel.CIChannel (nidaqmx._task_modules.channels.ci_channel.CIChannel
attribute), 139
attribute), 140
ci_encoder_decoding_type
ci_freq_logic_lvl_behavior
(nidaqmx._task_modules.channels.ci_channel.CIChannel (nidaqmx._task_modules.channels.ci_channel.CIChannel
attribute), 139
attribute), 140
ci_encoder_z_index_enable
ci_freq_meas_meth (nidaqmx._task_modules.channels.ci_channel.CIChann
(nidaqmx._task_modules.channels.ci_channel.CIChannel attribute), 140
attribute), 139
ci_freq_meas_time (nidaqmx._task_modules.channels.ci_channel.CIChanne
ci_encoder_z_index_phase
attribute), 141
(nidaqmx._task_modules.channels.ci_channel.CIChannel
ci_freq_starting_edge (nidaqmx._task_modules.channels.ci_channel.CIChan
attribute), 139
attribute), 141
ci_encoder_z_index_val (nidaqmx._task_modules.channels.ci_channel.CIChannel
ci_freq_term (nidaqmx._task_modules.channels.ci_channel.CIChannel
attribute), 140
attribute), 141
ci_encoder_z_input_dig_fltr_enable
ci_freq_term_cfg (nidaqmx._task_modules.channels.ci_channel.CIChannel
(nidaqmx._task_modules.channels.ci_channel.CIChannel attribute), 141
attribute), 140
ci_freq_units (nidaqmx._task_modules.channels.ci_channel.CIChannel
ci_encoder_z_input_dig_fltr_min_pulse_width
attribute), 141
(nidaqmx._task_modules.channels.ci_channel.CIChannel
ci_gps_sync_method (nidaqmx._task_modules.channels.ci_channel.CIChan
attribute), 140
attribute), 141
ci_encoder_z_input_dig_fltr_timebase_rate
ci_gps_sync_src (nidaqmx._task_modules.channels.ci_channel.CIChannel
(nidaqmx._task_modules.channels.ci_channel.CIChannel attribute), 141
attribute), 140
ci_lin_encoder_dist_per_pulse
ci_encoder_z_input_dig_fltr_timebase_src
(nidaqmx._task_modules.channels.ci_channel.CIChannel
(nidaqmx._task_modules.channels.ci_channel.CIChannel attribute), 141
attribute), 140
ci_lin_encoder_initial_pos
ci_encoder_z_input_dig_sync_enable
(nidaqmx._task_modules.channels.ci_channel.CIChannel
(nidaqmx._task_modules.channels.ci_channel.CIChannel attribute), 141
attribute), 140
ci_lin_encoder_units (nidaqmx._task_modules.channels.ci_channel.CIChan
ci_encoder_z_input_logic_lvl_behavior
attribute), 141
(nidaqmx._task_modules.channels.ci_channel.CIChannel
ci_max (nidaqmx._task_modules.channels.ci_channel.CIChannel
attribute), 140
attribute), 141
ci_encoder_z_input_term
ci_max_meas_period (nidaqmx._task_modules.channels.ci_channel.CIChan
(nidaqmx._task_modules.channels.ci_channel.CIChannel attribute), 141
attribute), 140
ci_max_size (nidaqmx.system.device.Device attribute),

Index

271

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101
attribute), 102
ci_max_timebase (nidaqmx.system.device.Device at- ci_prescaler (nidaqmx._task_modules.channels.ci_channel.CIChannel
tribute), 101
attribute), 143
ci_meas_type (nidaqmx._task_modules.channels.ci_channel.CIChannel
ci_pulse_freq_dig_fltr_enable
attribute), 141
(nidaqmx._task_modules.channels.ci_channel.CIChannel
ci_meas_types (nidaqmx.system.device.Device attribute),
attribute), 143
102
ci_pulse_freq_dig_fltr_min_pulse_width
ci_meas_types (nidaqmx.system.physical_channel.PhysicalChannel (nidaqmx._task_modules.channels.ci_channel.CIChannel
attribute), 105
attribute), 143
ci_mem_map_enable (nidaqmx._task_modules.channels.ci_channel.CIChannel
ci_pulse_freq_dig_fltr_timebase_rate
attribute), 141
(nidaqmx._task_modules.channels.ci_channel.CIChannel
ci_min (nidaqmx._task_modules.channels.ci_channel.CIChannel
attribute), 143
attribute), 142
ci_pulse_freq_dig_fltr_timebase_src
ci_num_possibly_invalid_samps
(nidaqmx._task_modules.channels.ci_channel.CIChannel
(nidaqmx._task_modules.channels.ci_channel.CIChannel attribute), 143
attribute), 142
ci_pulse_freq_dig_sync_enable
ci_output_state (nidaqmx._task_modules.channels.ci_channel.CIChannel
(nidaqmx._task_modules.channels.ci_channel.CIChannel
attribute), 142
attribute), 143
ci_period_dig_fltr_enable
ci_pulse_freq_logic_lvl_behavior
(nidaqmx._task_modules.channels.ci_channel.CIChannel (nidaqmx._task_modules.channels.ci_channel.CIChannel
attribute), 142
attribute), 143
ci_period_dig_fltr_min_pulse_width
ci_pulse_freq_starting_edge
(nidaqmx._task_modules.channels.ci_channel.CIChannel (nidaqmx._task_modules.channels.ci_channel.CIChannel
attribute), 142
attribute), 143
ci_period_dig_fltr_timebase_rate
ci_pulse_freq_term (nidaqmx._task_modules.channels.ci_channel.CIChann
(nidaqmx._task_modules.channels.ci_channel.CIChannel attribute), 143
attribute), 142
ci_pulse_freq_term_cfg (nidaqmx._task_modules.channels.ci_channel.CICh
ci_period_dig_fltr_timebase_src
attribute), 143
(nidaqmx._task_modules.channels.ci_channel.CIChannel
ci_pulse_freq_units (nidaqmx._task_modules.channels.ci_channel.CIChann
attribute), 142
attribute), 143
ci_period_dig_sync_enable
ci_pulse_ticks_dig_fltr_enable
(nidaqmx._task_modules.channels.ci_channel.CIChannel (nidaqmx._task_modules.channels.ci_channel.CIChannel
attribute), 142
attribute), 143
ci_period_div (nidaqmx._task_modules.channels.ci_channel.CIChannel
ci_pulse_ticks_dig_fltr_min_pulse_width
attribute), 142
(nidaqmx._task_modules.channels.ci_channel.CIChannel
ci_period_enable_averaging
attribute), 143
(nidaqmx._task_modules.channels.ci_channel.CIChannel
ci_pulse_ticks_dig_fltr_timebase_rate
attribute), 142
(nidaqmx._task_modules.channels.ci_channel.CIChannel
ci_period_logic_lvl_behavior
attribute), 143
(nidaqmx._task_modules.channels.ci_channel.CIChannel
ci_pulse_ticks_dig_fltr_timebase_src
attribute), 142
(nidaqmx._task_modules.channels.ci_channel.CIChannel
ci_period_meas_meth (nidaqmx._task_modules.channels.ci_channel.CIChannel
attribute), 143
attribute), 142
ci_pulse_ticks_dig_sync_enable
ci_period_meas_time (nidaqmx._task_modules.channels.ci_channel.CIChannel
(nidaqmx._task_modules.channels.ci_channel.CIChannel
attribute), 142
attribute), 143
ci_period_starting_edge (nidaqmx._task_modules.channels.ci_channel.CIChannel
ci_pulse_ticks_logic_lvl_behavior
attribute), 142
(nidaqmx._task_modules.channels.ci_channel.CIChannel
ci_period_term (nidaqmx._task_modules.channels.ci_channel.CIChannel
attribute), 144
attribute), 142
ci_pulse_ticks_starting_edge
ci_period_term_cfg (nidaqmx._task_modules.channels.ci_channel.CIChannel
(nidaqmx._task_modules.channels.ci_channel.CIChannel
attribute), 142
attribute), 144
ci_period_units (nidaqmx._task_modules.channels.ci_channel.CIChannel
ci_pulse_ticks_term (nidaqmx._task_modules.channels.ci_channel.CIChann
attribute), 143
attribute), 144
ci_physical_chans
(nidaqmx.system.device.Device ci_pulse_ticks_term_cfg (nidaqmx._task_modules.channels.ci_channel.CIC

272

Index

NI-DAQmx Python API Documentation, Release 0.5.0

attribute), 144
ci_pulse_width_units (nidaqmx._task_modules.channels.ci_channel.CIChan
ci_pulse_time_dig_fltr_enable
attribute), 145
(nidaqmx._task_modules.channels.ci_channel.CIChannel
ci_samp_clk_overrun_behavior
attribute), 144
(nidaqmx._task_modules.channels.ci_channel.CIChannel
ci_pulse_time_dig_fltr_min_pulse_width
attribute), 145
(nidaqmx._task_modules.channels.ci_channel.CIChannel
ci_samp_clk_overrun_sentinel_val
attribute), 144
(nidaqmx._task_modules.channels.ci_channel.CIChannel
ci_pulse_time_dig_fltr_timebase_rate
attribute), 145
(nidaqmx._task_modules.channels.ci_channel.CIChannel
ci_samp_clk_supported (nidaqmx.system.device.Device
attribute), 144
attribute), 102
ci_pulse_time_dig_fltr_timebase_src
ci_samp_modes (nidaqmx.system.device.Device at(nidaqmx._task_modules.channels.ci_channel.CIChannel tribute), 102
attribute), 144
ci_semi_period_dig_fltr_enable
ci_pulse_time_dig_sync_enable
(nidaqmx._task_modules.channels.ci_channel.CIChannel
(nidaqmx._task_modules.channels.ci_channel.CIChannel attribute), 145
attribute), 144
ci_semi_period_dig_fltr_min_pulse_width
ci_pulse_time_logic_lvl_behavior
(nidaqmx._task_modules.channels.ci_channel.CIChannel
(nidaqmx._task_modules.channels.ci_channel.CIChannel attribute), 145
attribute), 144
ci_semi_period_dig_fltr_timebase_rate
ci_pulse_time_starting_edge
(nidaqmx._task_modules.channels.ci_channel.CIChannel
(nidaqmx._task_modules.channels.ci_channel.CIChannel attribute), 145
attribute), 144
ci_semi_period_dig_fltr_timebase_src
ci_pulse_time_term (nidaqmx._task_modules.channels.ci_channel.CIChannel
(nidaqmx._task_modules.channels.ci_channel.CIChannel
attribute), 144
attribute), 145
ci_pulse_time_term_cfg (nidaqmx._task_modules.channels.ci_channel.CIChannel
ci_semi_period_dig_sync_enable
attribute), 144
(nidaqmx._task_modules.channels.ci_channel.CIChannel
ci_pulse_time_units (nidaqmx._task_modules.channels.ci_channel.CIChannel
attribute), 145
attribute), 144
ci_semi_period_logic_lvl_behavior
ci_pulse_width_dig_fltr_enable
(nidaqmx._task_modules.channels.ci_channel.CIChannel
(nidaqmx._task_modules.channels.ci_channel.CIChannel attribute), 145
attribute), 144
ci_semi_period_starting_edge
ci_pulse_width_dig_fltr_min_pulse_width
(nidaqmx._task_modules.channels.ci_channel.CIChannel
(nidaqmx._task_modules.channels.ci_channel.CIChannel attribute), 145
attribute), 144
ci_semi_period_term (nidaqmx._task_modules.channels.ci_channel.CIChan
ci_pulse_width_dig_fltr_timebase_rate
attribute), 145
(nidaqmx._task_modules.channels.ci_channel.CIChannel
ci_semi_period_term_cfg
attribute), 144
(nidaqmx._task_modules.channels.ci_channel.CIChannel
ci_pulse_width_dig_fltr_timebase_src
attribute), 145
(nidaqmx._task_modules.channels.ci_channel.CIChannel
ci_semi_period_units (nidaqmx._task_modules.channels.ci_channel.CIChan
attribute), 144
attribute), 145
ci_pulse_width_dig_sync_enable
ci_tc_reached (nidaqmx._task_modules.channels.ci_channel.CIChannel
(nidaqmx._task_modules.channels.ci_channel.CIChannel attribute), 145
attribute), 145
ci_thresh_voltage (nidaqmx._task_modules.channels.ci_channel.CIChannel
ci_pulse_width_logic_lvl_behavior
attribute), 146
(nidaqmx._task_modules.channels.ci_channel.CIChannel
ci_timestamp_initial_seconds
attribute), 145
(nidaqmx._task_modules.channels.ci_channel.CIChannel
ci_pulse_width_starting_edge
attribute), 146
(nidaqmx._task_modules.channels.ci_channel.CIChannel
ci_timestamp_units (nidaqmx._task_modules.channels.ci_channel.CIChann
attribute), 145
attribute), 146
ci_pulse_width_term (nidaqmx._task_modules.channels.ci_channel.CIChannel
ci_trig_usage (nidaqmx.system.device.Device attribute),
attribute), 145
102
ci_pulse_width_term_cfg
ci_two_edge_sep_first_dig_fltr_enable
(nidaqmx._task_modules.channels.ci_channel.CIChannel (nidaqmx._task_modules.channels.ci_channel.CIChannel
attribute), 145
attribute), 146

Index

273

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ci_two_edge_sep_first_dig_fltr_min_pulse_width
attribute), 147
(nidaqmx._task_modules.channels.ci_channel.CIChannel
ci_usb_xfer_req_size (nidaqmx._task_modules.channels.ci_channel.CIChan
attribute), 146
attribute), 147
ci_two_edge_sep_first_dig_fltr_timebase_rate
ci_velocity_a_input_dig_fltr_enable
(nidaqmx._task_modules.channels.ci_channel.CIChannel (nidaqmx._task_modules.channels.ci_channel.CIChannel
attribute), 146
attribute), 147
ci_two_edge_sep_first_dig_fltr_timebase_src
ci_velocity_a_input_dig_fltr_min_pulse_width
(nidaqmx._task_modules.channels.ci_channel.CIChannel (nidaqmx._task_modules.channels.ci_channel.CIChannel
attribute), 146
attribute), 147
ci_two_edge_sep_first_dig_sync_enable
ci_velocity_a_input_dig_fltr_timebase_rate
(nidaqmx._task_modules.channels.ci_channel.CIChannel (nidaqmx._task_modules.channels.ci_channel.CIChannel
attribute), 146
attribute), 147
ci_two_edge_sep_first_edge
ci_velocity_a_input_dig_fltr_timebase_src
(nidaqmx._task_modules.channels.ci_channel.CIChannel (nidaqmx._task_modules.channels.ci_channel.CIChannel
attribute), 146
attribute), 147
ci_two_edge_sep_first_logic_lvl_behavior
ci_velocity_a_input_logic_lvl_behavior
(nidaqmx._task_modules.channels.ci_channel.CIChannel (nidaqmx._task_modules.channels.ci_channel.CIChannel
attribute), 146
attribute), 147
ci_two_edge_sep_first_term
ci_velocity_a_input_term
(nidaqmx._task_modules.channels.ci_channel.CIChannel (nidaqmx._task_modules.channels.ci_channel.CIChannel
attribute), 146
attribute), 147
ci_two_edge_sep_first_term_cfg
ci_velocity_a_input_term_cfg
(nidaqmx._task_modules.channels.ci_channel.CIChannel (nidaqmx._task_modules.channels.ci_channel.CIChannel
attribute), 146
attribute), 147
ci_two_edge_sep_second_dig_fltr_enable
ci_velocity_ang_encoder_pulses_per_rev
(nidaqmx._task_modules.channels.ci_channel.CIChannel (nidaqmx._task_modules.channels.ci_channel.CIChannel
attribute), 146
attribute), 147
ci_two_edge_sep_second_dig_fltr_min_pulse_width
ci_velocity_ang_encoder_units
(nidaqmx._task_modules.channels.ci_channel.CIChannel (nidaqmx._task_modules.channels.ci_channel.CIChannel
attribute), 146
attribute), 147
ci_two_edge_sep_second_dig_fltr_timebase_rate
ci_velocity_b_input_dig_fltr_enable
(nidaqmx._task_modules.channels.ci_channel.CIChannel (nidaqmx._task_modules.channels.ci_channel.CIChannel
attribute), 146
attribute), 147
ci_two_edge_sep_second_dig_fltr_timebase_src
ci_velocity_b_input_dig_fltr_min_pulse_width
(nidaqmx._task_modules.channels.ci_channel.CIChannel (nidaqmx._task_modules.channels.ci_channel.CIChannel
attribute), 146
attribute), 147
ci_two_edge_sep_second_dig_sync_enable
ci_velocity_b_input_dig_fltr_timebase_rate
(nidaqmx._task_modules.channels.ci_channel.CIChannel (nidaqmx._task_modules.channels.ci_channel.CIChannel
attribute), 146
attribute), 147
ci_two_edge_sep_second_edge
ci_velocity_b_input_dig_fltr_timebase_src
(nidaqmx._task_modules.channels.ci_channel.CIChannel (nidaqmx._task_modules.channels.ci_channel.CIChannel
attribute), 146
attribute), 147
ci_two_edge_sep_second_logic_lvl_behavior
ci_velocity_b_input_logic_lvl_behavior
(nidaqmx._task_modules.channels.ci_channel.CIChannel (nidaqmx._task_modules.channels.ci_channel.CIChannel
attribute), 146
attribute), 148
ci_two_edge_sep_second_term
ci_velocity_b_input_term
(nidaqmx._task_modules.channels.ci_channel.CIChannel (nidaqmx._task_modules.channels.ci_channel.CIChannel
attribute), 147
attribute), 148
ci_two_edge_sep_second_term_cfg
ci_velocity_b_input_term_cfg
(nidaqmx._task_modules.channels.ci_channel.CIChannel (nidaqmx._task_modules.channels.ci_channel.CIChannel
attribute), 147
attribute), 148
ci_two_edge_sep_units (nidaqmx._task_modules.channels.ci_channel.CIChannel
ci_velocity_div (nidaqmx._task_modules.channels.ci_channel.CIChannel
attribute), 147
attribute), 148
ci_usb_xfer_req_count (nidaqmx._task_modules.channels.ci_channel.CIChannel
ci_velocity_encoder_decoding_type

274

Index

NI-DAQmx Python API Documentation, Release 0.5.0

(nidaqmx._task_modules.channels.ci_channel.CIChannel (nidaqmx._task_modules.channels.co_channel.COChannel
attribute), 148
attribute), 149
ci_velocity_lin_encoder_dist_per_pulse
co_ctr_timebase_master_timebase_div
(nidaqmx._task_modules.channels.ci_channel.CIChannel (nidaqmx._task_modules.channels.co_channel.COChannel
attribute), 148
attribute), 149
ci_velocity_lin_encoder_units
co_ctr_timebase_rate (nidaqmx._task_modules.channels.co_channel.COCha
(nidaqmx._task_modules.channels.ci_channel.CIChannel attribute), 150
attribute), 148
co_ctr_timebase_src (nidaqmx._task_modules.channels.co_channel.COCha
ci_velocity_meas_time (nidaqmx._task_modules.channels.ci_channel.CIChannel
attribute), 150
attribute), 148
co_data_xfer_mech (nidaqmx._task_modules.channels.co_channel.COChan
CIChannel (class in nidaqmx._task_modules.channels.ci_channel), attribute), 150
135
co_data_xfer_req_cond (nidaqmx._task_modules.channels.co_channel.COC
CIChannelCollection
(class
in
attribute), 150
nidaqmx._task_modules.ci_channel_collection), co_enable_initial_delay_on_retrigger
203
(nidaqmx._task_modules.channels.co_channel.COChannel
CIPhysicalChannelCollection
(class
in
attribute), 150
nidaqmx.system._collections.physical_channel_collection),
co_max_size (nidaqmx.system.device.Device attribute),
97
102
CJCSource (class in nidaqmx.constants), 22
co_max_timebase
(nidaqmx.system.device.Device
CLEAR_EXPIRATION (nidaqmx.constants.WDTTaskAction
attribute), 102
attribute), 50
co_mem_map_enable (nidaqmx._task_modules.channels.co_channel.COCh
clear_expiration() (nidaqmx.system.watchdog.WatchdogTask
attribute), 150
method), 110
co_output_state (nidaqmx._task_modules.channels.co_channel.COChannel
clear_teds() (nidaqmx.system.physical_channel.PhysicalChannel
attribute), 150
method), 105
co_output_type (nidaqmx._task_modules.channels.co_channel.COChannel
close()
(nidaqmx.system.watchdog.WatchdogTask
attribute), 150
method), 110
co_output_types (nidaqmx.system.device.Device atclose() (nidaqmx.task.Task method), 112
tribute), 102
CLOSED (nidaqmx.constants.RelayPosition attribute), co_output_types (nidaqmx.system.physical_channel.PhysicalChannel
36
attribute), 105
co_auto_incr_cnt (nidaqmx._task_modules.channels.co_channel.COChannel
co_physical_chans (nidaqmx.system.device.Device atattribute), 149
tribute), 102
co_channels (nidaqmx.task.Task attribute), 112
co_prescaler (nidaqmx._task_modules.channels.co_channel.COChannel
co_constrained_gen_mode
attribute), 150
(nidaqmx._task_modules.channels.co_channel.COChannel
co_pulse_done (nidaqmx._task_modules.channels.co_channel.COChannel
attribute), 149
attribute), 150
co_count (nidaqmx._task_modules.channels.co_channel.COChannel
co_pulse_duty_cyc (nidaqmx._task_modules.channels.co_channel.COChan
attribute), 149
attribute), 150
co_ctr_timebase_active_edge
co_pulse_freq (nidaqmx._task_modules.channels.co_channel.COChannel
(nidaqmx._task_modules.channels.co_channel.COChannel attribute), 150
attribute), 149
co_pulse_freq_initial_delay
co_ctr_timebase_dig_fltr_enable
(nidaqmx._task_modules.channels.co_channel.COChannel
(nidaqmx._task_modules.channels.co_channel.COChannel attribute), 150
attribute), 149
co_pulse_freq_units (nidaqmx._task_modules.channels.co_channel.COChan
co_ctr_timebase_dig_fltr_min_pulse_width
attribute), 150
(nidaqmx._task_modules.channels.co_channel.COChannel
co_pulse_high_ticks (nidaqmx._task_modules.channels.co_channel.COCha
attribute), 149
attribute), 151
co_ctr_timebase_dig_fltr_timebase_rate
co_pulse_high_time (nidaqmx._task_modules.channels.co_channel.COChan
(nidaqmx._task_modules.channels.co_channel.COChannel attribute), 151
attribute), 149
co_pulse_idle_state (nidaqmx._task_modules.channels.co_channel.COChan
co_ctr_timebase_dig_fltr_timebase_src
attribute), 151
(nidaqmx._task_modules.channels.co_channel.COChannel
co_pulse_low_ticks (nidaqmx._task_modules.channels.co_channel.COChan
attribute), 149
attribute), 151
co_ctr_timebase_dig_sync_enable
co_pulse_low_time (nidaqmx._task_modules.channels.co_channel.COChan

Index

275

NI-DAQmx Python API Documentation, Release 0.5.0

attribute), 151
method), 92
co_pulse_term (nidaqmx._task_modules.channels.co_channel.COChannel
CONSTANT_GROUP_DELAY
attribute), 151
(nidaqmx.constants.FilterResponse attribute),
co_pulse_ticks_initial_delay
28
(nidaqmx._task_modules.channels.co_channel.COChannel
CONSTANT_USER_VALUE
attribute), 151
(nidaqmx.constants.CJCSource
attribute),
co_pulse_time_initial_delay
22
(nidaqmx._task_modules.channels.co_channel.COChannel
ConstrainedGenMode (class in nidaqmx.constants), 23
attribute), 151
CONTINUOUS (nidaqmx.constants.AcquisitionType atco_pulse_time_units (nidaqmx._task_modules.channels.co_channel.COChannel
tribute), 19
attribute), 151
CONTINUOUS (nidaqmx.constants.ScanRepeatMode
co_rdy_for_new_val (nidaqmx._task_modules.channels.co_channel.COChannel
attribute), 38
attribute), 151
control()
(nidaqmx.system.watchdog.WatchdogTask
co_samp_clk_supported (nidaqmx.system.device.Device
method), 110
attribute), 102
control() (nidaqmx.task.Task method), 113
co_samp_modes (nidaqmx.system.device.Device at- COPhysicalChannelCollection
(class
in
tribute), 102
nidaqmx.system._collections.physical_channel_collection),
co_trig_usage (nidaqmx.system.device.Device attribute),
97
102
COULOMBS (nidaqmx.constants.ChargeUnits attribute),
co_usb_xfer_req_count (nidaqmx._task_modules.channels.co_channel.COChannel
23
attribute), 151
COULOMBS (nidaqmx.constants.UnitsPreScaled atco_usb_xfer_req_size (nidaqmx._task_modules.channels.co_channel.COChannel
tribute), 45
attribute), 151
count() (nidaqmx._task_modules.ai_channel_collection.AIChannelCollectio
co_use_only_on_brd_mem
method), 201
(nidaqmx._task_modules.channels.co_channel.COChannel
count() (nidaqmx._task_modules.ao_channel_collection.AOChannelCollect
attribute), 151
method), 202
COChannel (class in nidaqmx._task_modules.channels.co_channel),
count() (nidaqmx._task_modules.ci_channel_collection.CIChannelCollectio
149
method), 213
COChannelCollection
(class
in count() (nidaqmx._task_modules.co_channel_collection.COChannelCollect
nidaqmx._task_modules.co_channel_collection),
method), 215
213
count() (nidaqmx._task_modules.di_channel_collection.DIChannelCollectio
COExpirationState (class in nidaqmx.types), 248
method), 216
COMMIT (nidaqmx.constants.Action attribute), 19
count() (nidaqmx._task_modules.do_channel_collection.DOChannelCollect
common_mode_range_error_chans
method), 216
(nidaqmx._task_modules.in_stream.InStream
COUNT_DOWN (nidaqmx.constants.CountDirection atattribute), 220
tribute), 23
common_mode_range_error_chans_exist
COUNT_EDGES (nidaqmx.constants.UsageTypeCI at(nidaqmx._task_modules.in_stream.InStream
tribute), 48
attribute), 220
COUNT_UP (nidaqmx.constants.CountDirection atCOMPACT_DAQ
(nidaqmx.constants.BusType
attribute), 23
tribute), 21
CountDirection (class in nidaqmx.constants), 23
COMPACT_DAQ_CHASSIS
COUNTER_INPUT (nidaqmx.constants.ChannelType at(nidaqmx.constants.ProductCategory attribute),
tribute), 23
34
COUNTER_OUTPUT (nidaqmx.constants.ChannelType
compact_daq_chassis_device
attribute), 23
(nidaqmx.system.device.Device
attribute), COUNTER_OUTPUT_EVENT
102
(nidaqmx.constants.Signal attribute), 39
compact_daq_slot_num (nidaqmx.system.device.Device CounterFrequencyMethod (class in nidaqmx.constants),
attribute), 102
23
configure_logging() (nidaqmx._task_modules.in_stream.InStream
CounterReader (class in nidaqmx.stream_readers), 62
method), 220
CounterWriter (class in nidaqmx.stream_writers), 82
configure_teds() (nidaqmx.system.physical_channel.PhysicalChannel
Coupling (class in nidaqmx.constants), 24
method), 105
CREATE (nidaqmx.constants.LoggingOperation atconnect_terms()
(nidaqmx.system.system.System
tribute), 31

276

Index

NI-DAQmx Python API Documentation, Release 0.5.0

create_lin_scale() (nidaqmx.scale.Scale static method), D
53
DaqError, 51
create_map_scale() (nidaqmx.scale.Scale static method), DaqResourceWarning (in module nidaqmx.errors), 52
53
DaqWarning, 52
CREATE_OR_REPLACE
data_active_event_lvl_active_lvl
(nidaqmx.constants.LoggingOperation
at(nidaqmx._task_modules.export_signals.ExportSignals
tribute), 31
attribute), 217
create_polynomial_scale() (nidaqmx.scale.Scale static data_active_event_output_term
method), 54
(nidaqmx._task_modules.export_signals.ExportSignals
create_table_scale() (nidaqmx.scale.Scale static method),
attribute), 217
54
DataJustification (class in nidaqmx.constants), 24
ctr_out_event_output_behavior
DataTransferActiveTransferMode
(class
in
(nidaqmx._task_modules.export_signals.ExportSignals
nidaqmx.constants), 24
attribute), 217
DC (nidaqmx.constants.Coupling attribute), 24
ctr_out_event_output_term
DeassertCondition (class in nidaqmx.constants), 25
(nidaqmx._task_modules.export_signals.ExportSignals
DEFAULT (nidaqmx.constants.TerminalConfiguration atattribute), 217
tribute), 43
ctr_out_event_pulse_polarity
DEG_C (nidaqmx.constants.TemperatureUnits attribute),
(nidaqmx._task_modules.export_signals.ExportSignals
42
attribute), 217
DEG_C (nidaqmx.constants.UnitsPreScaled attribute), 45
ctr_out_event_toggle_idle_state
DEG_F (nidaqmx.constants.TemperatureUnits attribute),
(nidaqmx._task_modules.export_signals.ExportSignals
42
attribute), 217
DEG_F (nidaqmx.constants.UnitsPreScaled attribute), 45
CtrFreq (class in nidaqmx.types), 248
DEG_R (nidaqmx.constants.TemperatureUnits attribute),
CtrTick (class in nidaqmx.types), 248
42
CtrTime (class in nidaqmx.types), 248
DEG_R (nidaqmx.constants.UnitsPreScaled attribute), 45
curr_read_pos (nidaqmx._task_modules.in_stream.InStreamDEGREES (nidaqmx.constants.AngleUnits attribute), 19
attribute), 221
DEGREES
(nidaqmx.constants.UnitsPreScaled
atcurr_write_pos (nidaqmx._task_modules.out_stream.OutStream
tribute), 45
attribute), 226
DEGREES_PER_SECOND
CURRENT (nidaqmx.constants.AOPowerUpOutputBehavior
(nidaqmx.constants.AngularVelocityUnits
attribute), 18
attribute), 19
CURRENT (nidaqmx.constants.UsageTypeAI attribute), DEGREES_PER_SECOND
47
(nidaqmx.constants.UnitsPreScaled attribute),
CURRENT (nidaqmx.constants.UsageTypeAO attribute),
45
48
delay (nidaqmx._task_modules.triggering.reference_trigger.ReferenceTrigge
CURRENT (nidaqmx.constants.WatchdogAOExpirState
attribute), 243
attribute), 50
delay (nidaqmx._task_modules.triggering.start_trigger.StartTrigger
CURRENT_ACRMS (nidaqmx.constants.UsageTypeAI
attribute), 246
attribute), 47
delay_from_samp_clk_delay
CURRENT_READ_POSITION
(nidaqmx._task_modules.timing.Timing
(nidaqmx.constants.ReadRelativeTo attribute),
attribute), 233
36
delay_from_samp_clk_delay_units
CURRENT_WRITE_POSITION
(nidaqmx._task_modules.timing.Timing
(nidaqmx.constants.WriteRelativeTo attribute),
attribute), 233
51
delay_units (nidaqmx._task_modules.triggering.start_trigger.StartTrigger
CurrentShuntResistorLocation
(class
in
attribute), 246
nidaqmx.constants), 24
delete() (nidaqmx.system.storage.persisted_channel.PersistedChannel
CurrentUnits (class in nidaqmx.constants), 24
method), 107
CUSTOM (nidaqmx.constants.ADCTimingMode at- delete() (nidaqmx.system.storage.persisted_scale.PersistedScale
tribute), 17
method), 108
CUSTOM (nidaqmx.constants.FilterType attribute), 28
delete() (nidaqmx.system.storage.persisted_task.PersistedTask
CUSTOM (nidaqmx.constants.RTDType attribute), 35
method), 108
delete_network_device() (nidaqmx.system.device.Device
Index

277

NI-DAQmx Python API Documentation, Release 0.5.0

method), 102
attribute), 153
DELTA (nidaqmx.constants.StrainGageRosetteType at- di_dig_fltr_timebase_rate
tribute), 41
(nidaqmx._task_modules.channels.di_channel.DIChannel
description (nidaqmx._task_modules.channels.ai_channel.AIChannel attribute), 153
attribute), 130
di_dig_fltr_timebase_src (nidaqmx._task_modules.channels.di_channel.DIC
description (nidaqmx._task_modules.channels.ao_channel.AOChannelattribute), 153
attribute), 134
di_dig_sync_enable (nidaqmx._task_modules.channels.di_channel.DIChann
description (nidaqmx._task_modules.channels.channel.Channel
attribute), 153
attribute), 118
di_invert_lines (nidaqmx._task_modules.channels.di_channel.DIChannel
description (nidaqmx._task_modules.channels.ci_channel.CIChannel attribute), 153
attribute), 148
di_lines (nidaqmx.system.device.Device attribute), 103
description (nidaqmx._task_modules.channels.co_channel.COChannel
di_logic_family (nidaqmx._task_modules.channels.di_channel.DIChannel
attribute), 151
attribute), 153
description (nidaqmx._task_modules.channels.di_channel.DIChannel
di_max_rate (nidaqmx.system.device.Device attribute),
attribute), 152
103
description (nidaqmx._task_modules.channels.do_channel.DOChannel
di_mem_map_enable (nidaqmx._task_modules.channels.di_channel.DIChan
attribute), 154
attribute), 153
description (nidaqmx.scale.Scale attribute), 54
di_num_booleans_per_chan
DEU (nidaqmx.constants.Language attribute), 30
(nidaqmx._task_modules.in_stream.InStream
dev_is_simulated (nidaqmx.system.device.Device atattribute), 221
tribute), 102
di_num_lines (nidaqmx._task_modules.channels.di_channel.DIChannel
dev_serial_num (nidaqmx.system.device.Device atattribute), 153
tribute), 102
di_port_width (nidaqmx.system.physical_channel.PhysicalChannel
Device (class in nidaqmx.system.device), 98
attribute), 106
device_names (nidaqmx.system._collections.device_collection.DeviceCollection
di_ports (nidaqmx.system.device.Device attribute), 103
attribute), 96
di_samp_clk_supported (nidaqmx.system.physical_channel.PhysicalChanne
DeviceCollection
(class
in
attribute), 106
nidaqmx.system._collections.device_collection), di_samp_modes (nidaqmx.system.physical_channel.PhysicalChannel
96
attribute), 106
devices (nidaqmx.system.system.System attribute), 92
di_trig_usage (nidaqmx.system.device.Device attribute),
devices (nidaqmx.task.Task attribute), 113
103
devs_with_inserted_or_removed_accessories
di_tristate (nidaqmx._task_modules.channels.di_channel.DIChannel
(nidaqmx._task_modules.in_stream.InStream
attribute), 153
attribute), 221
di_usb_xfer_req_count (nidaqmx._task_modules.channels.di_channel.DICh
devs_with_inserted_or_removed_accessories
attribute), 153
(nidaqmx._task_modules.out_stream.OutStream di_usb_xfer_req_size (nidaqmx._task_modules.channels.di_channel.DIChan
attribute), 226
attribute), 153
di_acquire_on (nidaqmx._task_modules.channels.di_channel.DIChannel
DIChannel (class in nidaqmx._task_modules.channels.di_channel),
attribute), 152
152
di_change_detect_supported
DIChannelCollection
(class
in
(nidaqmx.system.physical_channel.PhysicalChannel
nidaqmx._task_modules.di_channel_collection),
attribute), 106
215
di_channels (nidaqmx.task.Task attribute), 113
DIFF (nidaqmx.constants.CalibrationTerminalConfig atdi_data_xfer_mech (nidaqmx._task_modules.channels.di_channel.DIChannel
tribute), 22
attribute), 152
DIFFERENTIAL (nidaqmx.constants.TerminalConfiguration
di_data_xfer_req_cond (nidaqmx._task_modules.channels.di_channel.DIChannel
attribute), 43
attribute), 152
dig_edge_dig_fltr_enable
di_dig_fltr_enable (nidaqmx._task_modules.channels.di_channel.DIChannel
(nidaqmx._task_modules.triggering.arm_start_trigger.ArmStartTr
attribute), 152
attribute), 237
di_dig_fltr_enable_bus_mode
dig_edge_dig_fltr_enable
(nidaqmx._task_modules.channels.di_channel.DIChannel (nidaqmx._task_modules.triggering.reference_trigger.ReferenceT
attribute), 152
attribute), 243
di_dig_fltr_min_pulse_width
dig_edge_dig_fltr_enable
(nidaqmx._task_modules.channels.di_channel.DIChannel (nidaqmx._task_modules.triggering.start_trigger.StartTrigger

278

Index

NI-DAQmx Python API Documentation, Release 0.5.0

attribute), 246
dig_lvl_dig_fltr_timebase_rate
dig_edge_dig_fltr_min_pulse_width
(nidaqmx._task_modules.triggering.pause_trigger.PauseTrigger
(nidaqmx._task_modules.triggering.arm_start_trigger.ArmStartTrigger
attribute), 239
attribute), 237
dig_lvl_dig_fltr_timebase_src
dig_edge_dig_fltr_min_pulse_width
(nidaqmx._task_modules.triggering.pause_trigger.PauseTrigger
(nidaqmx._task_modules.triggering.reference_trigger.ReferenceTrigger
attribute), 239
attribute), 243
dig_lvl_dig_sync_enable
dig_edge_dig_fltr_min_pulse_width
(nidaqmx._task_modules.triggering.pause_trigger.PauseTrigger
(nidaqmx._task_modules.triggering.start_trigger.StartTriggerattribute), 239
attribute), 246
dig_lvl_src (nidaqmx._task_modules.triggering.pause_trigger.PauseTrigger
dig_edge_dig_fltr_timebase_rate
attribute), 239
(nidaqmx._task_modules.triggering.arm_start_trigger.ArmStartTrigger
dig_lvl_when (nidaqmx._task_modules.triggering.pause_trigger.PauseTrigg
attribute), 237
attribute), 239
dig_edge_dig_fltr_timebase_rate
dig_pattern_pattern (nidaqmx._task_modules.triggering.pause_trigger.Pause
(nidaqmx._task_modules.triggering.reference_trigger.ReferenceTrigger
attribute), 239
attribute), 243
dig_pattern_pattern (nidaqmx._task_modules.triggering.reference_trigger.R
dig_edge_dig_fltr_timebase_rate
attribute), 243
(nidaqmx._task_modules.triggering.start_trigger.StartTrigger
dig_pattern_pattern (nidaqmx._task_modules.triggering.start_trigger.StartTr
attribute), 246
attribute), 247
dig_edge_dig_fltr_timebase_src
dig_pattern_src (nidaqmx._task_modules.triggering.pause_trigger.PauseTrig
(nidaqmx._task_modules.triggering.arm_start_trigger.ArmStartTrigger
attribute), 239
attribute), 237
dig_pattern_src (nidaqmx._task_modules.triggering.reference_trigger.Refer
dig_edge_dig_fltr_timebase_src
attribute), 243
(nidaqmx._task_modules.triggering.reference_trigger.ReferenceTrigger
dig_pattern_src (nidaqmx._task_modules.triggering.start_trigger.StartTrigge
attribute), 243
attribute), 247
dig_edge_dig_fltr_timebase_src
dig_pattern_trig_when (nidaqmx._task_modules.triggering.reference_trigge
(nidaqmx._task_modules.triggering.start_trigger.StartTriggerattribute), 243
attribute), 247
dig_pattern_trig_when (nidaqmx._task_modules.triggering.start_trigger.Star
dig_edge_dig_sync_enable
attribute), 247
(nidaqmx._task_modules.triggering.arm_start_trigger.ArmStartTrigger
dig_pattern_when (nidaqmx._task_modules.triggering.pause_trigger.PauseT
attribute), 237
attribute), 239
dig_edge_dig_sync_enable
dig_trig_supported (nidaqmx.system.device.Device at(nidaqmx._task_modules.triggering.reference_trigger.ReferenceTrigger
tribute), 103
attribute), 243
DIGITAL_EDGE
(nidaqmx.constants.TriggerType
dig_edge_dig_sync_enable
attribute), 44
(nidaqmx._task_modules.triggering.start_trigger.StartTrigger
DIGITAL_INPUT (nidaqmx.constants.ChannelType atattribute), 247
tribute), 23
dig_edge_edge (nidaqmx._task_modules.triggering.arm_start_trigger.ArmStartTrigger
DIGITAL_IO (nidaqmx.constants.ProductCategory atattribute), 237
tribute), 34
dig_edge_edge (nidaqmx._task_modules.triggering.reference_trigger.ReferenceTrigger
DIGITAL_LEVEL (nidaqmx.constants.TriggerType atattribute), 243
tribute), 44
dig_edge_edge (nidaqmx._task_modules.triggering.start_trigger.StartTrigger
DIGITAL_OUTPUT (nidaqmx.constants.ChannelType
attribute), 247
attribute), 23
dig_edge_src (nidaqmx._task_modules.triggering.arm_start_trigger.ArmStartTrigger
DIGITAL_PATTERN (nidaqmx.constants.TriggerType
attribute), 237
attribute), 44
dig_edge_src (nidaqmx._task_modules.triggering.reference_trigger.ReferenceTrigger
DigitalDriveType (class in nidaqmx.constants), 25
attribute), 243
DigitalMultiChannelReader
(class
in
dig_edge_src (nidaqmx._task_modules.triggering.start_trigger.StartTrigger
nidaqmx.stream_readers), 72
attribute), 247
DigitalMultiChannelWriter
(class
in
dig_lvl_dig_fltr_enable (nidaqmx._task_modules.triggering.pause_trigger.PauseTrigger
nidaqmx.stream_writers), 87
attribute), 239
DigitalPatternCondition (class in nidaqmx.constants), 25
dig_lvl_dig_fltr_min_pulse_width
DigitalSingleChannelReader
(class
in
(nidaqmx._task_modules.triggering.pause_trigger.PauseTrigger
nidaqmx.stream_readers), 68
attribute), 239
DigitalSingleChannelWriter
(class
in

Index

279

NI-DAQmx Python API Documentation, Release 0.5.0

nidaqmx.stream_writers), 84
attribute), 226
DigitalWidthUnits (class in nidaqmx.constants), 25
do_num_lines (nidaqmx._task_modules.channels.do_channel.DOChannel
DILinesCollection
(class
in
attribute), 155
nidaqmx.system._collections.physical_channel_collection),
do_output_drive_type (nidaqmx._task_modules.channels.do_channel.DOCh
97
attribute), 155
DIPortsCollection
(class
in do_overcurrent_auto_reenable
nidaqmx.system._collections.physical_channel_collection), (nidaqmx._task_modules.channels.do_channel.DOChannel
98
attribute), 155
disable_ref_trig() (nidaqmx._task_modules.triggering.reference_trigger.ReferenceTrigger
do_overcurrent_limit (nidaqmx._task_modules.channels.do_channel.DOCha
method), 243
attribute), 155
disable_start_trig() (nidaqmx._task_modules.triggering.start_trigger.StartTrigger
do_overcurrent_reenable_period
method), 247
(nidaqmx._task_modules.channels.do_channel.DOChannel
disconnect_terms()
(nidaqmx.system.system.System
attribute), 155
method), 92
do_port_width (nidaqmx.system.physical_channel.PhysicalChannel
divided_samp_clk_timebase_output_term
attribute), 106
(nidaqmx._task_modules.export_signals.ExportSignals
do_ports (nidaqmx.system.device.Device attribute), 103
attribute), 218
do_samp_clk_supported (nidaqmx.system.physical_channel.PhysicalChann
DMA (nidaqmx.constants.DataTransferActiveTransferMode
attribute), 106
attribute), 24
do_samp_modes (nidaqmx.system.physical_channel.PhysicalChannel
do_channels (nidaqmx.task.Task attribute), 113
attribute), 106
do_data_xfer_mech (nidaqmx._task_modules.channels.do_channel.DOChannel
do_trig_usage (nidaqmx.system.device.Device attribute),
attribute), 154
103
do_data_xfer_req_cond (nidaqmx._task_modules.channels.do_channel.DOChannel
do_tristate (nidaqmx._task_modules.channels.do_channel.DOChannel
attribute), 154
attribute), 155
do_generate_on (nidaqmx._task_modules.channels.do_channel.DOChannel
do_usb_xfer_req_count (nidaqmx._task_modules.channels.do_channel.DOC
attribute), 154
attribute), 155
do_invert_lines (nidaqmx._task_modules.channels.do_channel.DOChannel
do_usb_xfer_req_size (nidaqmx._task_modules.channels.do_channel.DOCh
attribute), 154
attribute), 155
do_line_states_done_state
do_use_only_on_brd_mem
(nidaqmx._task_modules.channels.do_channel.DOChannel (nidaqmx._task_modules.channels.do_channel.DOChannel
attribute), 155
attribute), 155
do_line_states_paused_state
DOChannel (class in nidaqmx._task_modules.channels.do_channel),
(nidaqmx._task_modules.channels.do_channel.DOChannel 154
attribute), 155
DOChannelCollection
(class
in
do_line_states_start_state
nidaqmx._task_modules.do_channel_collection),
(nidaqmx._task_modules.channels.do_channel.DOChannel 216
attribute), 155
DOExpirationState (class in nidaqmx.types), 248
do_lines (nidaqmx.system.device.Device attribute), 103
DOLinesCollection
(class
in
do_logic_family (nidaqmx._task_modules.channels.do_channel.DOChannel
nidaqmx.system._collections.physical_channel_collection),
attribute), 155
98
do_max_rate (nidaqmx.system.device.Device attribute), DONT_ALLOW_REGENERATION
103
(nidaqmx.constants.RegenerationMode
atdo_mem_map_enable (nidaqmx._task_modules.channels.do_channel.DOChannel
tribute), 36
attribute), 155
DOPortsCollection
(class
in
DO_NOT_INVERT_POLARITY
nidaqmx.system._collections.physical_channel_collection),
(nidaqmx.constants.SignalModifiers attribute),
98
40
DOPowerUpState (class in nidaqmx.types), 249
DO_NOT_OVERWRITE_UNREAD_SAMPLES
DOResistorPowerUpState (class in nidaqmx.types), 249
(nidaqmx.constants.OverwriteMode attribute), driver_version
(nidaqmx.system.system.System
at33
tribute), 93
DO_NOT_WRITE (nidaqmx.constants.WriteBasicTEDSOptions
DSA (nidaqmx.constants.ProductCategory attribute), 34
attribute), 51
DUTY_CYCLE
(nidaqmx.constants.UsageTypeCI
do_num_booleans_per_chan
attribute), 48
(nidaqmx._task_modules.out_stream.OutStream duty_cycle (nidaqmx.types.CtrFreq attribute), 248

280

Index

NI-DAQmx Python API Documentation, Release 0.5.0

DYNAMIC_AVERAGING
(nidaqmx.constants.CounterFrequencyMethod
attribute), 23

expir_trig_dig_edge_src (nidaqmx.system.watchdog.WatchdogTask
attribute), 110
expir_trig_trig_on_network_conn_loss
(nidaqmx.system.watchdog.WatchdogTask
E
attribute), 110
expir_trig_trig_type (nidaqmx.system.watchdog.WatchdogTask
E (nidaqmx.constants.ThermocoupleType attribute), 43
attribute), 110
E_SERIES_DAQ (nidaqmx.constants.ProductCategory
expiration_state (nidaqmx.types.AOExpirationState atattribute), 34
tribute), 247
EddyCurrentProxProbeSensitivityUnits
(class
in
expiration_state (nidaqmx.types.COExpirationState atnidaqmx.constants), 25
tribute), 248
Edge (class in nidaqmx.constants), 26
expiration_state (nidaqmx.types.DOExpirationState atEIGHT_M_HZ_TIMEBASE
tribute), 248
(nidaqmx.constants.MIOAIConvertTimebaseSource
expiration_states (nidaqmx.system.watchdog.WatchdogTask
attribute), 32
attribute), 110
EIGHTY_M_HZ_TIMEBASE
ExpirationState
(class
in
(nidaqmx.constants.MIOAIConvertTimebaseSource
nidaqmx.system._watchdog_modules.expiration_state),
attribute), 32
111
ELLIPTICAL (nidaqmx.constants.FilterResponse atExpirationStatesCollection
(class
in
tribute), 28
nidaqmx.system._watchdog_modules.expiration_states_collection
EncoderType (class in nidaqmx.constants), 26
111
EncoderZIndexPhase (class in nidaqmx.constants), 26
expired
(nidaqmx.system.watchdog.WatchdogTask
ENG (nidaqmx.constants.Language attribute), 30
attribute), 111
ENTERING_WINDOW (nidaqmx.constants.WindowTriggerCondition1
export_signal() (nidaqmx._task_modules.export_signals.ExportSignals
attribute), 51
method), 218
error_code (nidaqmx.errors.DaqError attribute), 51
export_signals (nidaqmx.task.Task attribute), 113
error_code (nidaqmx.errors.DaqWarning attribute), 52
ExportAction (class in nidaqmx.constants), 27
error_type (nidaqmx.errors.DaqError attribute), 52
exported_10_m_hz_ref_clk_output_term
error_type (nidaqmx.errors.DaqWarning attribute), 52
(nidaqmx._task_modules.export_signals.ExportSignals
EVERY_SAMPLE (nidaqmx.constants.AutoZeroType
attribute), 218
attribute), 20
EveryNSamplesEventType (class in nidaqmx.constants), exported_20_m_hz_timebase_output_term
(nidaqmx._task_modules.export_signals.ExportSignals
26
attribute), 218
excit_fault_chans (nidaqmx._task_modules.in_stream.InStream
ExportSignals
(class
in
attribute), 221
excit_fault_chans_exist (nidaqmx._task_modules.in_stream.InStream nidaqmx._task_modules.export_signals),
216
attribute), 221
EXTERNAL (nidaqmx.constants.CurrentShuntResistorLocation
ExcitationDCorAC (class in nidaqmx.constants), 26
attribute), 24
ExcitationIdleOutputBehavior
(class
in
EXTERNAL (nidaqmx.constants.ExcitationSource atnidaqmx.constants), 27
tribute), 27
ExcitationSource (class in nidaqmx.constants), 27
ExcitationVoltageOrCurrent (class in nidaqmx.constants), EXTERNAL (nidaqmx.constants.SourceSelection attribute), 40
27
external_overvoltage_chans
expir_states_ao_state (nidaqmx.system._watchdog_modules.expiration_state.ExpirationState
(nidaqmx._task_modules.out_stream.OutStream
attribute), 111
attribute), 226
expir_states_ao_type (nidaqmx.system._watchdog_modules.expiration_state.ExpirationState
external_overvoltage_chans_exist
attribute), 111
(nidaqmx._task_modules.out_stream.OutStream
expir_states_co_state (nidaqmx.system._watchdog_modules.expiration_state.ExpirationState
attribute), 226
attribute), 111
EXTERNAL_SOURCE
(nidaqmx.constants.CountDirection
expir_states_do_state (nidaqmx.system._watchdog_modules.expiration_state.ExpirationState
attribute),
23
attribute), 111
expir_trig_dig_edge_edge
F
(nidaqmx.system.watchdog.WatchdogTask
attribute), 110
FALLING (nidaqmx.constants.Edge attribute), 26
FALLING (nidaqmx.constants.Slope attribute), 40
Index

281

NI-DAQmx Python API Documentation, Release 0.5.0

FIFTY_OHMS (nidaqmx.constants.Impedance1 at18
tribute), 29
FROM_CUSTOM_SCALE
FillMode (class in nidaqmx.constants), 27
(nidaqmx.constants.AngleUnits
attribute),
FilterResponse (class in nidaqmx.constants), 27
19
FilterType (class in nidaqmx.constants), 28
FROM_CUSTOM_SCALE
FINITE (nidaqmx.constants.AcquisitionType attribute),
(nidaqmx.constants.AngularVelocityUnits
19
attribute), 19
FINITE (nidaqmx.constants.ScanRepeatMode attribute), FROM_CUSTOM_SCALE
38
(nidaqmx.constants.BridgeUnits
attribute),
FIRST_PRETRIGGER_SAMPLE
21
(nidaqmx.constants.ReadRelativeTo attribute), FROM_CUSTOM_SCALE
36
(nidaqmx.constants.ChargeUnits
attribute),
FIRST_SAMPLE (nidaqmx.constants.ReadRelativeTo
23
attribute), 36
FROM_CUSTOM_SCALE
FIRST_SAMPLE (nidaqmx.constants.WriteRelativeTo
(nidaqmx.constants.CurrentUnits attribute), 24
attribute), 51
FROM_CUSTOM_SCALE
FIVE_V (nidaqmx.constants.LogicFamily attribute), 32
(nidaqmx.constants.ForceUnits
attribute),
FIVE_WIRE (nidaqmx.constants.ACExcitWireMode at28
tribute), 17
FROM_CUSTOM_SCALE
FIXED_50_PERCENT_DUTY_CYCLE
(nidaqmx.constants.FrequencyUnits attribute),
(nidaqmx.constants.ConstrainedGenMode
28
attribute), 23
FROM_CUSTOM_SCALE
FIXED_HIGH_FREQ (nidaqmx.constants.ConstrainedGenMode
(nidaqmx.constants.LengthUnits
attribute),
attribute), 23
30
FIXED_LOW_FREQ (nidaqmx.constants.ConstrainedGenMode
FROM_CUSTOM_SCALE
attribute), 23
(nidaqmx.constants.PressureUnits attribute), 34
flatten_channel_string() (in module nidaqmx.utils), 249
FROM_CUSTOM_SCALE
FM (nidaqmx.constants.ModulationType attribute), 32
(nidaqmx.constants.ResistanceUnits attribute),
FOOT_POUNDS (nidaqmx.constants.BridgePhysicalUnits
36
attribute), 20
FROM_CUSTOM_SCALE
FOOT_POUNDS
(nidaqmx.constants.TorqueUnits
(nidaqmx.constants.SoundPressureUnits
attribute), 44
attribute), 40
FOOT_POUNDS (nidaqmx.constants.UnitsPreScaled at- FROM_CUSTOM_SCALE
tribute), 45
(nidaqmx.constants.StrainUnits
attribute),
FORCE_BRIDGE (nidaqmx.constants.UsageTypeAI at41
tribute), 47
FROM_CUSTOM_SCALE
FORCE_IEPE_SENSOR
(nidaqmx.constants.TEDSUnits
attribute),
(nidaqmx.constants.UsageTypeAI attribute), 47
42
ForceIEPESensorSensitivityUnits
(class
in FROM_CUSTOM_SCALE
nidaqmx.constants), 28
(nidaqmx.constants.TemperatureUnits
atForceUnits (class in nidaqmx.constants), 28
tribute), 43
FOUR_WIRE (nidaqmx.constants.ACExcitWireMode at- FROM_CUSTOM_SCALE
tribute), 17
(nidaqmx.constants.TimeUnits
attribute),
FOUR_WIRE (nidaqmx.constants.ResistanceConfiguration
43
attribute), 36
FROM_CUSTOM_SCALE
FRA (nidaqmx.constants.Language attribute), 30
(nidaqmx.constants.TorqueUnits
attribute),
freq (nidaqmx.types.CtrFreq attribute), 248
44
FREQUENCY (nidaqmx.constants.UsageTypeCI at- FROM_CUSTOM_SCALE
tribute), 48
(nidaqmx.constants.VelocityUnits attribute), 49
FREQUENCY_VOLTAGE
FROM_CUSTOM_SCALE
(nidaqmx.constants.UsageTypeAI attribute), 47
(nidaqmx.constants.VoltageUnits
attribute),
FrequencyUnits (class in nidaqmx.constants), 28
50
FROM_CUSTOM_SCALE
FROM_TEDS
(nidaqmx.constants.BridgeUnits
at(nidaqmx.constants.AccelUnits
attribute),
tribute), 21

282

Index

NI-DAQmx Python API Documentation, Release 0.5.0

FROM_TEDS (nidaqmx.constants.CurrentUnits at- GROUP_BY_SCAN_NUMBER
tribute), 24
(nidaqmx.constants.FillMode attribute), 27
FROM_TEDS (nidaqmx.constants.ResistanceUnits atH
tribute), 37
FROM_TEDS (nidaqmx.constants.TEDSUnits attribute), HALF_BRIDGE (nidaqmx.constants.BridgeConfiguration
42
attribute), 20
FROM_TEDS
(nidaqmx.constants.UnitsPreScaled HALF_BRIDGE_I (nidaqmx.constants.StrainGageBridgeType
attribute), 45
attribute), 40
FROM_TEDS (nidaqmx.constants.VoltageUnits at- HALF_BRIDGE_II (nidaqmx.constants.StrainGageBridgeType
tribute), 50
attribute), 40
FULL_BRIDGE (nidaqmx.constants.BridgeConfiguration HALT_OUTPUT_AND_ERROR
attribute), 20
(nidaqmx.constants.UnderflowBehavior
atFULL_BRIDGE_I (nidaqmx.constants.StrainGageBridgeType
tribute), 45
attribute), 40
HANDSHAKE (nidaqmx.constants.SampleTimingType
FULL_BRIDGE_II (nidaqmx.constants.StrainGageBridgeType
attribute), 38
attribute), 40
HANDSHAKE (nidaqmx.constants.TriggerUsage atFULL_BRIDGE_III (nidaqmx.constants.StrainGageBridgeType
tribute), 44
attribute), 40
handshake_trigger (nidaqmx._task_modules.triggers.Triggers
FuncGenType (class in nidaqmx.constants), 29
attribute), 236
FUNCTION_GENERATION
HANDSHAKE_TRIGGER_ASSERTS
(nidaqmx.constants.UsageTypeAO attribute),
(nidaqmx.constants.SampleInputDataWhen
48
attribute), 37
HANDSHAKE_TRIGGER_DEASSERTS
G
(nidaqmx.constants.SampleInputDataWhen
G (nidaqmx.constants.AccelUnits attribute), 18
attribute), 37
G (nidaqmx.constants.UnitsPreScaled attribute), 45
HandshakeStartCondition (class in nidaqmx.constants),
get_analog_power_up_states()
29
(nidaqmx.system.system.System
method), HandshakeTrigger
(class
in
93
nidaqmx._task_modules.triggering.handshake_trigger),
get_analog_power_up_states_with_output_type()
237
(nidaqmx.system.system.System
method), HARDWARE_DEFINED
93
(nidaqmx.constants.FilterResponse attribute),
get_digital_logic_family_power_up_state()
28
(nidaqmx.system.system.System
method), HERTZ (nidaqmx.constants.UnitsPreScaled attribute), 45
93
HIGH (nidaqmx.constants.Level attribute), 31
get_digital_power_up_states()
HIGH (nidaqmx.constants.PowerUpStates attribute), 33
(nidaqmx.system.system.System
method), HIGH (nidaqmx.constants.WatchdogCOExpirState at94
tribute), 50
get_digital_pull_up_pull_down_states()
HIGH_FREQUENCY_2_COUNTERS
(nidaqmx.system.system.System
method),
(nidaqmx.constants.CounterFrequencyMethod
94
attribute), 23
global_channel_names (nidaqmx.system._collections.persisted_channel_collection.PersistedChannelCollection
HIGH_IMPEDANCE (nidaqmx.constants.AOIdleOutputBehavior
attribute), 96
attribute), 18
global_channels (nidaqmx.system.system.System at- HIGH_IMPEDANCE (nidaqmx.constants.AOPowerUpOutputBehavior
tribute), 94
attribute), 18
GND (nidaqmx.constants.Coupling attribute), 24
HIGH_RESOLUTION (nidaqmx.constants.ADCTimingMode
GNORE_OVERRUNS (nidaqmx.constants.OverflowBehavior
attribute), 17
attribute), 33
HIGH_SPEED (nidaqmx.constants.ADCTimingMode atGpsSignalType (class in nidaqmx.constants), 29
tribute), 17
GROUND (nidaqmx.constants.InputCalSource attribute), high_tick (nidaqmx.types.CtrTick attribute), 248
30
high_time (nidaqmx.types.CtrTime attribute), 248
GROUP_BY_CHANNEL (nidaqmx.constants.FillMode HIGHPASS (nidaqmx.constants.FilterType attribute), 28
attribute), 27
hshk_delay_after_xfer (nidaqmx._task_modules.timing.Timing
attribute), 233
Index

283

NI-DAQmx Python API Documentation, Release 0.5.0

hshk_event_delay (nidaqmx._task_modules.export_signals.ExportSignals
INCH_POUNDS (nidaqmx.constants.BridgePhysicalUnits
attribute), 218
attribute), 21
hshk_event_interlocked_assert_on_start
INCH_POUNDS
(nidaqmx.constants.TorqueUnits
(nidaqmx._task_modules.export_signals.ExportSignals
attribute), 44
attribute), 218
INCH_POUNDS (nidaqmx.constants.UnitsPreScaled athshk_event_interlocked_asserted_lvl
tribute), 46
(nidaqmx._task_modules.export_signals.ExportSignals
INCHES (nidaqmx.constants.LengthUnits attribute), 30
attribute), 218
INCHES (nidaqmx.constants.UnitsPreScaled attribute),
hshk_event_interlocked_deassert_delay
45
(nidaqmx._task_modules.export_signals.ExportSignals
INCHES_PER_SECOND
attribute), 218
(nidaqmx.constants.UnitsPreScaled attribute),
hshk_event_output_behavior
45
(nidaqmx._task_modules.export_signals.ExportSignals
INCHES_PER_SECOND
attribute), 218
(nidaqmx.constants.VelocityUnits attribute), 49
hshk_event_output_term (nidaqmx._task_modules.export_signals.ExportSignals
INCHES_PER_SECOND_SQUARED
attribute), 218
(nidaqmx.constants.AccelUnits
attribute),
hshk_event_pulse_polarity
18
(nidaqmx._task_modules.export_signals.ExportSignals
INCHES_PER_SECOND_SQUARED
attribute), 218
(nidaqmx.constants.UnitsPreScaled attribute),
hshk_event_pulse_width (nidaqmx._task_modules.export_signals.ExportSignals
45
attribute), 218
index() (nidaqmx._task_modules.ai_channel_collection.AIChannelCollectio
hshk_sample_input_data_when
method), 201
(nidaqmx._task_modules.timing.Timing
index() (nidaqmx._task_modules.ao_channel_collection.AOChannelCollect
attribute), 233
method), 202
hshk_start_cond (nidaqmx._task_modules.timing.Timing index() (nidaqmx._task_modules.ci_channel_collection.CIChannelCollectio
attribute), 233
method), 213
HW_TIMED_SINGLE_POINT
index() (nidaqmx._task_modules.co_channel_collection.COChannelCollect
(nidaqmx.constants.AcquisitionType attribute),
method), 215
19
index() (nidaqmx._task_modules.di_channel_collection.DIChannelCollectio
HZ (nidaqmx.constants.FrequencyUnits attribute), 28
method), 216
index() (nidaqmx._task_modules.do_channel_collection.DOChannelCollect
I
method), 216
INI (nidaqmx.constants.TaskStringFormat attribute), 42
IL (nidaqmx.constants.EddyCurrentProxProbeSensitivityUnits
input_buf_size (nidaqmx._task_modules.in_stream.InStream
attribute), 25
attribute), 221
ILLIMETER (nidaqmx.constants.EddyCurrentProxProbeSensitivityUnits
input_onbrd_buf_size (nidaqmx._task_modules.in_stream.InStream
attribute), 25
attribute), 221
IMMEDIATE (nidaqmx.constants.HandshakeStartCondition
input_port
(nidaqmx.types.CDAQSyncConnection
attribute), 29
attribute), 248
Impedance1 (class in nidaqmx.constants), 29
IMPLICIT (nidaqmx.constants.SampleTimingType at- InputCalSource (class in nidaqmx.constants), 30
InputDataTransferCondition
(class
in
tribute), 38
nidaqmx.constants), 30
implicit_underflow_behavior
INSIDE_WINDOW (nidaqmx.constants.WindowTriggerCondition2
(nidaqmx._task_modules.timing.Timing
attribute), 51
attribute), 233
InStream (class in nidaqmx._task_modules.in_stream),
in_stream (nidaqmx.task.Task attribute), 113
220
INACTIVE (nidaqmx.constants.ActiveOrInactiveEdgeSelection
INTERLOCKED
(nidaqmx.constants.ExportAction atattribute), 19
tribute),
27
INCH_OUNCES (nidaqmx.constants.BridgePhysicalUnits
INTERLOCKED
(nidaqmx.constants.TriggerType
attribute), 21
attribute),
44
INCH_OUNCES
(nidaqmx.constants.TorqueUnits
interlocked_asserted_lvl (nidaqmx._task_modules.triggering.handshake_trig
attribute), 44
attribute), 237
INCH_OUNCES (nidaqmx.constants.UnitsPreScaled atinterlocked_src
(nidaqmx._task_modules.triggering.handshake_trigger.Hand
tribute), 46
attribute), 237

284

Index

NI-DAQmx Python API Documentation, Release 0.5.0

INTERNAL (nidaqmx.constants.CurrentShuntResistorLocation
LET_DRIVER_CHOOSE
attribute), 24
(nidaqmx.constants.CurrentShuntResistorLocation
INTERNAL
(nidaqmx.constants.ExcitationSource
attribute), 24
attribute), 27
Level (class in nidaqmx.constants), 31
INTERNAL (nidaqmx.constants.SourceSelection at- LEVEL (nidaqmx.constants.ExportAction attribute), 27
tribute), 40
lin_slope (nidaqmx.scale.Scale attribute), 54
INTERRUPT (nidaqmx.constants.DataTransferActiveTransferMode
lin_y_intercept (nidaqmx.scale.Scale attribute), 55
attribute), 24
LINEAR (nidaqmx.constants.ScaleType attribute), 38
INVERT_POLARITY (nidaqmx.constants.SignalModifiers LineGrouping (class in nidaqmx.constants), 31
attribute), 40
load() (nidaqmx.system.storage.persisted_scale.PersistedScale
IRIGB (nidaqmx.constants.GpsSignalType attribute), 29
method), 108
is_global (nidaqmx._task_modules.channels.ai_channel.AIChannel
load() (nidaqmx.system.storage.persisted_task.PersistedTask
attribute), 130
method), 108
is_global (nidaqmx._task_modules.channels.ao_channel.AOChannel
LOAD_CHANNEL (nidaqmx.constants.SwitchChannelUsage
attribute), 134
attribute), 41
is_global (nidaqmx._task_modules.channels.channel.Channel
LOCAL (nidaqmx.constants.Sense attribute), 38
attribute), 118
local() (nidaqmx.system.system.System static method),
is_global (nidaqmx._task_modules.channels.ci_channel.CIChannel 94
attribute), 148
LOG (nidaqmx.constants.LoggingMode attribute), 31
is_global (nidaqmx._task_modules.channels.co_channel.COChannel
LOG_AND_READ (nidaqmx.constants.LoggingMode
attribute), 151
attribute), 31
is_global (nidaqmx._task_modules.channels.di_channel.DIChannel
logging_file_path (nidaqmx._task_modules.in_stream.InStream
attribute), 153
attribute), 221
is_global (nidaqmx._task_modules.channels.do_channel.DOChannel
logging_file_preallocation_size
attribute), 156
(nidaqmx._task_modules.in_stream.InStream
is_task_done() (nidaqmx.task.Task method), 113
attribute), 221
logging_file_write_size (nidaqmx._task_modules.in_stream.InStream
J
attribute), 221
logging_mode (nidaqmx._task_modules.in_stream.InStream
J (nidaqmx.constants.ThermocoupleType attribute), 43
attribute), 221
JPN (nidaqmx.constants.Language attribute), 30
JSON (nidaqmx.constants.TaskStringFormat attribute), logging_pause (nidaqmx._task_modules.in_stream.InStream
attribute), 222
42
logging_samps_per_file (nidaqmx._task_modules.in_stream.InStream
K
attribute), 222
logging_tdms_group_name
K (nidaqmx.constants.TemperatureUnits attribute), 43
(nidaqmx._task_modules.in_stream.InStream
K (nidaqmx.constants.ThermocoupleType attribute), 43
attribute), 222
K (nidaqmx.constants.UnitsPreScaled attribute), 46
logging_tdms_operation (nidaqmx._task_modules.in_stream.InStream
KILOGRAM_FORCE (nidaqmx.constants.BridgePhysicalUnits
attribute), 222
attribute), 21
KILOGRAM_FORCE (nidaqmx.constants.ForceUnits LoggingMode (class in nidaqmx.constants), 31
LoggingOperation (class in nidaqmx.constants), 31
attribute), 28
KILOGRAM_FORCE (nidaqmx.constants.UnitsPreScaled LogicFamily (class in nidaqmx.constants), 31
LogicLvlBehavior (class in nidaqmx.constants), 32
attribute), 46
LOOPBACK_0 (nidaqmx.constants.InputCalSource atKOR (nidaqmx.constants.Language attribute), 30
tribute), 30
LOOPBACK_180
(nidaqmx.constants.InputCalSource
L
attribute),
30
Language (class in nidaqmx.constants), 30
LOSSLESS_PACKING (nidaqmx.constants.RawDataCompressionType
LARGE_RANGE_2_COUNTERS
attribute), 35
(nidaqmx.constants.CounterFrequencyMethod
LOSSY_LSB_REMOVAL
attribute), 24
LEAVING_WINDOW (nidaqmx.constants.WindowTriggerCondition1(nidaqmx.constants.RawDataCompressionType
attribute), 35
attribute), 51
LOW
(nidaqmx.constants.Level
attribute), 31
LEFT (nidaqmx.constants.DataJustification attribute), 24
LOW
(nidaqmx.constants.PowerUpStates
attribute), 33
LengthUnits (class in nidaqmx.constants), 30
Index

285

NI-DAQmx Python API Documentation, Release 0.5.0

LOW

(nidaqmx.constants.WatchdogCOExpirState
attribute), 50
LOW_FREQUENCY_1_COUNTER
(nidaqmx.constants.CounterFrequencyMethod
attribute), 24
low_tick (nidaqmx.types.CtrTick attribute), 248
low_time (nidaqmx.types.CtrTime attribute), 248
LOWPASS (nidaqmx.constants.FilterType attribute), 28
LVDTSensitivityUnits (class in nidaqmx.constants), 30

MAP_RANGES
(nidaqmx.constants.ScaleType
attribute), 38
map_scaled_max (nidaqmx.scale.Scale attribute), 55
map_scaled_min (nidaqmx.scale.Scale attribute), 55
MASTER (nidaqmx.constants.SyncType attribute), 42
MASTER_TIMEBASE (nidaqmx.constants.MIOAIConvertTimebaseSource
attribute), 32
master_timebase_rate (nidaqmx._task_modules.timing.Timing
attribute), 234
master_timebase_src (nidaqmx._task_modules.timing.Timing
M
attribute), 234
M_SERIES_DAQ (nidaqmx.constants.ProductCategory MAX_SHEAR_STRAIN
(nidaqmx.constants.StrainGageRosetteMeasurementType
attribute), 34
attribute), 41
M_VOLTS_PER_G (nidaqmx.constants.AccelSensitivityUnits
MAX_SHEAR_STRAIN_ANGLE
attribute), 18
(nidaqmx.constants.StrainGageRosetteMeasurementType
M_VOLTS_PER_INCH_PER_SECOND
(nidaqmx.constants.VelocityIEPESensorSensitivityUnits attribute), 41
METERS (nidaqmx.constants.LengthUnits attribute), 30
attribute), 49
METERS (nidaqmx.constants.UnitsPreScaled attribute),
M_VOLTS_PER_MILLIMETER_PER_SECOND
(nidaqmx.constants.VelocityIEPESensorSensitivityUnits 46
METERS_PER_SECOND
attribute), 49
(nidaqmx.constants.UnitsPreScaled attribute),
M_VOLTS_PER_NEWTON
46
(nidaqmx.constants.ForceIEPESensorSensitivityUnits
METERS_PER_SECOND
attribute), 28
(nidaqmx.constants.VelocityUnits attribute), 49
M_VOLTS_PER_POUND
METERS_PER_SECOND_SQUARED
(nidaqmx.constants.ForceIEPESensorSensitivityUnits
(nidaqmx.constants.AccelUnits
attribute),
attribute), 28
M_VOLTS_PER_VOLT (nidaqmx.constants.BridgeElectricalUnits 18
METERS_PER_SECOND_SQUARED
attribute), 20
(nidaqmx.constants.UnitsPreScaled attribute),
M_VOLTS_PER_VOLT (nidaqmx.constants.BridgeUnits
46
attribute), 21
M_VOLTS_PER_VOLT (nidaqmx.constants.UnitsPreScaledMICRON (nidaqmx.constants.EddyCurrentProxProbeSensitivityUnits
attribute), 26
attribute), 46
MIL (nidaqmx.constants.EddyCurrentProxProbeSensitivityUnits
M_VOLTS_PER_VOLT_PER_MILLI_INCH
attribute), 26
(nidaqmx.constants.LVDTSensitivityUnits
MILLIMETER (nidaqmx.constants.EddyCurrentProxProbeSensitivityUnits
attribute), 30
attribute), 26
M_VOLTS_PER_VOLT_PER_MILLIMETER
MIOAIConvertTimebaseSource
(class
in
(nidaqmx.constants.LVDTSensitivityUnits
nidaqmx.constants), 32
attribute), 30
ModulationType (class in nidaqmx.constants), 32
M_VPER_VPER_DEGREE
MOST_RECENT_SAMPLE
(nidaqmx.constants.RVDTSensitivityUnits
(nidaqmx.constants.ReadRelativeTo attribute),
attribute), 35
36
M_VPER_VPER_RADIAN
(nidaqmx.constants.RVDTSensitivityUnits
N
attribute), 35
N (nidaqmx.constants.ThermocoupleType attribute), 43
MAINTAIN_EXISTING_VALUE
name (nidaqmx._task_modules.channels.ai_channel.AIChannel
(nidaqmx.constants.AOIdleOutputBehavior
attribute), 130
attribute), 18
name (nidaqmx._task_modules.channels.ao_channel.AOChannel
MAINTAIN_EXISTING_VALUE
attribute), 134
(nidaqmx.constants.ExcitationIdleOutputBehavior
name (nidaqmx._task_modules.channels.channel.Channel
attribute), 27
attribute), 118
map_pre_scaled_max (nidaqmx.scale.Scale attribute), 55
map_pre_scaled_min (nidaqmx.scale.Scale attribute), 55 name (nidaqmx._task_modules.channels.ci_channel.CIChannel
attribute), 148
286

Index

NI-DAQmx Python API Documentation, Release 0.5.0

name (nidaqmx._task_modules.channels.co_channel.COChannel
ule), 213
attribute), 151
nidaqmx._task_modules.di_channel_collection (module),
name (nidaqmx._task_modules.channels.di_channel.DIChannel
215
attribute), 153
nidaqmx._task_modules.do_channel_collection (modname (nidaqmx._task_modules.channels.do_channel.DOChannel
ule), 216
attribute), 156
nidaqmx._task_modules.export_signals (module), 216
name (nidaqmx.scale.Scale attribute), 55
nidaqmx._task_modules.in_stream (module), 220
name (nidaqmx.system.device.Device attribute), 103
nidaqmx._task_modules.out_stream (module), 226
name (nidaqmx.system.physical_channel.PhysicalChannel nidaqmx._task_modules.timing (module), 229
attribute), 106
nidaqmx._task_modules.triggering.arm_start_trigger
name (nidaqmx.system.watchdog.WatchdogTask at(module), 236
tribute), 111
nidaqmx._task_modules.triggering.handshake_trigger
name (nidaqmx.task.Task attribute), 113
(module), 237
NEG_10_TO_10_V (nidaqmx.constants.SCXI1124Range nidaqmx._task_modules.triggering.pause_trigger (modattribute), 37
ule), 237
NEG_1_TO_1_V (nidaqmx.constants.SCXI1124Range nidaqmx._task_modules.triggering.reference_trigger
attribute), 37
(module), 240
NEG_5_TO_5_V (nidaqmx.constants.SCXI1124Range nidaqmx._task_modules.triggering.start_trigger (modattribute), 37
ule), 244
NETWORK_DAQ (nidaqmx.constants.ProductCategory nidaqmx._task_modules.triggers (module), 236
attribute), 34
nidaqmx.constants (module), 17
NEWTON_METERS (nidaqmx.constants.BridgePhysicalUnits
nidaqmx.errors (module), 51
attribute), 21
nidaqmx.scale (module), 52
NEWTON_METERS (nidaqmx.constants.TorqueUnits nidaqmx.stream_readers (module), 56
attribute), 44
nidaqmx.stream_writers (module), 77
NEWTON_METERS (nidaqmx.constants.UnitsPreScaled nidaqmx.system._collections.device_collection
(modattribute), 46
ule), 96
NEWTONS (nidaqmx.constants.BridgePhysicalUnits at- nidaqmx.system._collections.persisted_channel_collection
tribute), 21
(module), 96
NEWTONS (nidaqmx.constants.ForceUnits attribute), 28 nidaqmx.system._collections.persisted_scale_collection
NEWTONS (nidaqmx.constants.UnitsPreScaled at(module), 97
tribute), 46
nidaqmx.system._collections.persisted_task_collection
nidaqmx._task_modules.ai_channel_collection (module),
(module), 97
156
nidaqmx.system._collections.physical_channel_collection
nidaqmx._task_modules.ao_channel_collection
(mod(module), 97
ule), 201
nidaqmx.system._watchdog_modules.expiration_state
nidaqmx._task_modules.channel_collection
(module),
(module), 111
156
nidaqmx.system._watchdog_modules.expiration_states_collection
nidaqmx._task_modules.channels.ai_channel (module),
(module), 111
119
nidaqmx.system.device (module), 98
nidaqmx._task_modules.channels.ao_channel (module), nidaqmx.system.physical_channel (module), 104
131
nidaqmx.system.storage.persisted_channel (module), 107
nidaqmx._task_modules.channels.channel (module), 118 nidaqmx.system.storage.persisted_scale (module), 107
nidaqmx._task_modules.channels.ci_channel (module), nidaqmx.system.storage.persisted_task (module), 108
135
nidaqmx.system.system (module), 91
nidaqmx._task_modules.channels.co_channel (module), nidaqmx.system.watchdog (module), 109
149
nidaqmx.task (module), 112
nidaqmx._task_modules.channels.di_channel (module), nidaqmx.types (module), 247
152
nidaqmx.utils (module), 249
nidaqmx._task_modules.channels.do_channel (module), NIELVIS (nidaqmx.constants.ProductCategory attribute),
154
34
nidaqmx._task_modules.ci_channel_collection (module), NO_ACTION (nidaqmx.constants.BreakMode attribute),
203
20
nidaqmx._task_modules.co_channel_collection
(mod- NO_BRIDGE (nidaqmx.constants.BridgeConfiguration

Index

287

NI-DAQmx Python API Documentation, Release 0.5.0

attribute), 20
(nidaqmx.constants.DeassertCondition
atNO_CHANGE (nidaqmx.constants.Level attribute), 31
tribute), 25
NO_CHANGE (nidaqmx.constants.WatchdogAOExpirStateON_BOARD_MEMORY_MORE_THAN_HALF_FULL
attribute), 50
(nidaqmx.constants.InputDataTransferCondition
NO_CHANGE (nidaqmx.constants.WatchdogCOExpirState
attribute), 30
attribute), 50
ON_BOARD_MEMORY_NOT_EMPTY
NONE (nidaqmx.constants.AutoZeroType attribute), 20
(nidaqmx.constants.InputDataTransferCondition
NONE (nidaqmx.constants.ExcitationSource attribute),
attribute), 30
27
ON_DEMAND (nidaqmx.constants.SampleTimingType
NONE (nidaqmx.constants.GpsSignalType attribute), 29
attribute), 38
NONE (nidaqmx.constants.LogicLvlBehavior attribute), ONBOARD_MEMORY_CUSTOM_THRESHOLD
32
(nidaqmx.constants.DeassertCondition
atNONE (nidaqmx.constants.ModulationType attribute), 32
tribute), 25
NONE (nidaqmx.constants.RawDataCompressionType ONBOARD_MEMORY_CUSTOM_THRESHOLD
attribute), 36
(nidaqmx.constants.InputDataTransferCondition
NONE (nidaqmx.constants.ScaleType attribute), 38
attribute), 30
NONE
(nidaqmx.constants.ShuntElementLocation ONCE (nidaqmx.constants.AutoZeroType attribute), 20
attribute), 39
ONE_HUNDRED_M_HZ_TIMEBASE
NONE (nidaqmx.constants.SyncType attribute), 42
(nidaqmx.constants.MIOAIConvertTimebaseSource
NONE (nidaqmx.constants.TriggerType attribute), 44
attribute), 32
NOTCH (nidaqmx.constants.FilterType attribute), 28
ONE_M_OHM (nidaqmx.constants.Impedance1 atNRSE (nidaqmx.constants.TerminalConfiguration attribute), 29
tribute), 43
OPEN (nidaqmx.constants.LoggingOperation attribute),
num_chans (nidaqmx._task_modules.in_stream.InStream
31
attribute), 222
OPEN (nidaqmx.constants.RelayPosition attribute), 36
num_chans (nidaqmx._task_modules.out_stream.OutStreamopen_chans (nidaqmx._task_modules.in_stream.InStream
attribute), 227
attribute), 222
num_dma_chans (nidaqmx.system.device.Device at- open_chans_details (nidaqmx._task_modules.in_stream.InStream
tribute), 103
attribute), 222
number_of_channels (nidaqmx.task.Task attribute), 113
open_chans_exist (nidaqmx._task_modules.in_stream.InStream
number_of_devices (nidaqmx.task.Task attribute), 113
attribute), 222
OPEN_COLLECTOR (nidaqmx.constants.DigitalDriveType
O
attribute), 25
open_current_loop_chans
OFF (nidaqmx.constants.LoggingMode attribute), 31
(nidaqmx._task_modules.in_stream.InStream
offset (nidaqmx._task_modules.in_stream.InStream atattribute), 222
tribute), 222
offset (nidaqmx._task_modules.out_stream.OutStream open_current_loop_chans
(nidaqmx._task_modules.out_stream.OutStream
attribute), 227
attribute), 227
OHMS (nidaqmx.constants.ResistanceUnits attribute), 37
OHMS (nidaqmx.constants.UnitsPreScaled attribute), 46 open_current_loop_chans_exist
(nidaqmx._task_modules.in_stream.InStream
ON_BOARD_MEMORY_EMPTY
attribute), 222
(nidaqmx.constants.OutputDataTransferCondition
open_current_loop_chans_exist
attribute), 32
(nidaqmx._task_modules.out_stream.OutStream
ON_BOARD_MEMORY_FULL
attribute), 227
(nidaqmx.constants.DeassertCondition
atOPEN_OR_CREATE
(nidaqmx.constants.LoggingOperation
tribute), 25
attribute),
31
ON_BOARD_MEMORY_HALF_FULL_OR_LESS
(nidaqmx.constants.OutputDataTransferConditionopen_thrmcpl_chans (nidaqmx._task_modules.in_stream.InStream
attribute), 222
attribute), 32
open_thrmcpl_chans_exist
ON_BOARD_MEMORY_LESS_THAN_FULL
(nidaqmx._task_modules.in_stream.InStream
(nidaqmx.constants.OutputDataTransferCondition
attribute), 223
attribute), 32
out_stream
(nidaqmx.task.Task attribute), 113
ON_BOARD_MEMORY_MORE_THAN_HALF_FULL
output_buf_size (nidaqmx._task_modules.out_stream.OutStream

288

Index

NI-DAQmx Python API Documentation, Release 0.5.0

attribute), 227
PATH_ALREADY_EXISTS
output_onbrd_buf_size (nidaqmx._task_modules.out_stream.OutStream
(nidaqmx.constants.PathCapability attribute),
attribute), 227
33
output_port (nidaqmx.types.CDAQSyncConnection at- PATH_AVAILABLE (nidaqmx.constants.PathCapability
tribute), 248
attribute), 33
output_type
(nidaqmx.types.AOExpirationState
at- PATH_UNSUPPORTED
tribute), 247
(nidaqmx.constants.PathCapability attribute),
OutputDataTransferCondition
(class
in
33
nidaqmx.constants), 32
PathCapability (class in nidaqmx.constants), 33
OUTSIDE_WINDOW (nidaqmx.constants.WindowTriggerCondition2
PATTERN_DOES_NOT_MATCH
attribute), 51
(nidaqmx.constants.DigitalPatternCondition
OutStream (class in nidaqmx._task_modules.out_stream),
attribute), 25
226
PATTERN_MATCHES (nidaqmx.constants.DigitalPatternCondition
over_write (nidaqmx._task_modules.in_stream.InStream
attribute), 25
attribute), 223
PAUSE (nidaqmx.constants.TriggerUsage attribute), 44
overcurrent_chans (nidaqmx._task_modules.in_stream.InStream
pause_trig_lvl_active_lvl
attribute), 223
(nidaqmx._task_modules.export_signals.ExportSignals
overcurrent_chans (nidaqmx._task_modules.out_stream.OutStream attribute), 218
attribute), 227
pause_trig_output_term (nidaqmx._task_modules.export_signals.ExportSign
overcurrent_chans_exist (nidaqmx._task_modules.in_stream.InStreamattribute), 218
attribute), 223
pause_trigger (nidaqmx._task_modules.triggers.Triggers
overcurrent_chans_exist (nidaqmx._task_modules.out_stream.OutStream
attribute), 236
attribute), 227
PauseTrigger
(class
in
OverflowBehavior (class in nidaqmx.constants), 33
nidaqmx._task_modules.triggering.pause_trigger),
overloaded_chans (nidaqmx._task_modules.in_stream.InStream
237
attribute), 223
PC_CARD (nidaqmx.constants.BusType attribute), 21
overloaded_chans (nidaqmx._task_modules.out_stream.OutStream
PCI (nidaqmx.constants.BusType attribute), 21
attribute), 227
pci_bus_num (nidaqmx.system.device.Device attribute),
overloaded_chans_exist (nidaqmx._task_modules.in_stream.InStream 103
attribute), 223
pci_dev_num (nidaqmx.system.device.Device attribute),
overloaded_chans_exist (nidaqmx._task_modules.out_stream.OutStream
103
attribute), 227
PCIE (nidaqmx.constants.BusType attribute), 21
overtemperature_chans (nidaqmx._task_modules.in_stream.InStream
PERIOD (nidaqmx.constants.UsageTypeCI attribute), 48
attribute), 223
PersistedChannel
(class
in
overtemperature_chans (nidaqmx._task_modules.out_stream.OutStream
nidaqmx.system.storage.persisted_channel),
attribute), 227
107
overtemperature_chans_exist
PersistedChannelCollection
(class
in
(nidaqmx._task_modules.in_stream.InStream
nidaqmx.system._collections.persisted_channel_collection),
attribute), 223
96
overtemperature_chans_exist
PersistedScale
(class
in
(nidaqmx._task_modules.out_stream.OutStream
nidaqmx.system.storage.persisted_scale),
attribute), 227
107
OVERWRITE_UNREAD_SAMPLES
PersistedScaleCollection
(class
in
(nidaqmx.constants.OverwriteMode attribute),
nidaqmx.system._collections.persisted_scale_collection),
33
97
OverwriteMode (class in nidaqmx.constants), 33
PersistedTask
(class
in
nidaqmx.system.storage.persisted_task),
P
108
PersistedTaskCollection
(class
in
PA (nidaqmx.constants.SoundPressureUnits attribute), 40
nidaqmx.system._collections.persisted_task_collection),
PA (nidaqmx.constants.UnitsPreScaled attribute), 46
97
PASCALS (nidaqmx.constants.BridgePhysicalUnits atphysical_channel
(nidaqmx._task_modules.channels.ai_channel.AIChannel
tribute), 21
attribute),
130
PASCALS (nidaqmx.constants.PressureUnits attribute),
physical_channel
(nidaqmx._task_modules.channels.ao_channel.AOChanne
34
Index

289

NI-DAQmx Python API Documentation, Release 0.5.0

attribute), 134
POSITION_ANGULAR_RVDT
physical_channel (nidaqmx._task_modules.channels.channel.Channel (nidaqmx.constants.UsageTypeAI attribute), 47
attribute), 118
POSITION_EDDY_CURRENT_PROX_PROBE
physical_channel (nidaqmx._task_modules.channels.ci_channel.CIChannel
(nidaqmx.constants.UsageTypeAI attribute), 47
attribute), 148
POSITION_LINEAR_ENCODER
physical_channel (nidaqmx._task_modules.channels.co_channel.COChannel
(nidaqmx.constants.UsageTypeCI attribute), 48
attribute), 151
POSITION_LINEAR_LVDT
physical_channel (nidaqmx._task_modules.channels.di_channel.DIChannel
(nidaqmx.constants.UsageTypeAI attribute), 47
attribute), 153
POUNDS (nidaqmx.constants.BridgePhysicalUnits atphysical_channel (nidaqmx._task_modules.channels.do_channel.DOChannel
tribute), 21
attribute), 156
POUNDS (nidaqmx.constants.ForceUnits attribute), 28
physical_channel (nidaqmx.types.AOExpirationState at- POUNDS (nidaqmx.constants.UnitsPreScaled attribute),
tribute), 247
46
physical_channel (nidaqmx.types.AOPowerUpState at- POUNDS_PER_SQ_INCH
tribute), 248
(nidaqmx.constants.BridgePhysicalUnits
physical_channel (nidaqmx.types.COExpirationState atattribute), 21
tribute), 248
POUNDS_PER_SQ_INCH
physical_channel (nidaqmx.types.DOExpirationState at(nidaqmx.constants.PressureUnits attribute), 34
tribute), 249
POUNDS_PER_SQ_INCH
physical_channel (nidaqmx.types.DOPowerUpState at(nidaqmx.constants.UnitsPreScaled attribute),
tribute), 249
46
physical_channel (nidaqmx.types.DOResistorPowerUpStatepower_supply_fault_chans
attribute), 249
(nidaqmx._task_modules.out_stream.OutStream
PhysicalChannel
(class
in
attribute), 227
nidaqmx.system.physical_channel), 104
power_supply_fault_chans_exist
PhysicalChannelCollection
(class
in
(nidaqmx._task_modules.out_stream.OutStream
nidaqmx.system._collections.physical_channel_collection), attribute), 227
98
power_up_state
(nidaqmx.types.AOPowerUpState
PICO_COULOMBS (nidaqmx.constants.ChargeUnits atattribute), 248
tribute), 23
power_up_state
(nidaqmx.types.DOPowerUpState
PICO_COULOMBS (nidaqmx.constants.UnitsPreScaled
attribute), 249
attribute), 46
power_up_state (nidaqmx.types.DOResistorPowerUpState
PICO_COULOMBS_PER_G
attribute), 249
(nidaqmx.constants.AccelChargeSensitivityUnits PowerUpChannelType (class in nidaqmx.constants), 33
attribute), 18
PowerUpStates (class in nidaqmx.constants), 33
PICO_COULOMBS_PER_INCHES_PER_SECOND_SQUARED
PPS (nidaqmx.constants.GpsSignalType attribute), 29
(nidaqmx.constants.AccelChargeSensitivityUnits pre_scaled_units (nidaqmx.scale.Scale attribute), 55
attribute), 18
PRESSURE_BRIDGE (nidaqmx.constants.UsageTypeAI
PICO_COULOMBS_PER_METERS_PER_SECOND_SQUARED attribute), 47
(nidaqmx.constants.AccelChargeSensitivityUnits PressureUnits (class in nidaqmx.constants), 34
attribute), 18
pretrig_samples (nidaqmx._task_modules.triggering.reference_trigger.Refer
PIPELINED_SAMPLE_CLOCK
attribute), 243
(nidaqmx.constants.SampleTimingType
at- PRINCIPAL_STRAIN_1
tribute), 38
(nidaqmx.constants.StrainGageRosetteMeasurementType
Polarity (class in nidaqmx.constants), 33
attribute), 41
POLL (nidaqmx.constants.WaitMode attribute), 50
PRINCIPAL_STRAIN_2
POLLED (nidaqmx.constants.DataTransferActiveTransferMode
(nidaqmx.constants.StrainGageRosetteMeasurementType
attribute), 25
attribute), 41
poly_forward_coeff (nidaqmx.scale.Scale attribute), 55
PRINCIPAL_STRAIN_ANGLE
poly_reverse_coeff (nidaqmx.scale.Scale attribute), 55
(nidaqmx.constants.StrainGageRosetteMeasurementType
POLYNOMIAL (nidaqmx.constants.ScaleType attribute),
attribute), 41
38
product_category (nidaqmx.system.device.Device atPOSITION_ANGULAR_ENCODER
tribute), 103
(nidaqmx.constants.UsageTypeCI attribute), 48 product_num (nidaqmx.system.device.Device attribute),

290

Index

NI-DAQmx Python API Documentation, Release 0.5.0

103
attribute), 41
product_type (nidaqmx.system.device.Device attribute),
R
103
ProductCategory (class in nidaqmx.constants), 34
R (nidaqmx.constants.ThermocoupleType attribute), 43
PSEUDO_DIFF (nidaqmx.constants.CalibrationTerminalConfig
R_1 (nidaqmx.constants.ShuntElementLocation atattribute), 22
tribute), 39
PSEUDODIFFERENTIAL
R_2 (nidaqmx.constants.ShuntElementLocation at(nidaqmx.constants.TerminalConfiguration
tribute), 39
attribute), 43
R_3 (nidaqmx.constants.ShuntElementLocation atPT_3750 (nidaqmx.constants.RTDType attribute), 35
tribute), 39
PT_3851 (nidaqmx.constants.RTDType attribute), 35
R_4 (nidaqmx.constants.ShuntElementLocation atPT_3911 (nidaqmx.constants.RTDType attribute), 35
tribute), 39
PT_3916 (nidaqmx.constants.RTDType attribute), 35
RADIANS (nidaqmx.constants.AngleUnits attribute), 19
PT_3920 (nidaqmx.constants.RTDType attribute), 35
RADIANS (nidaqmx.constants.UnitsPreScaled attribute),
PT_3928 (nidaqmx.constants.RTDType attribute), 35
46
PULL_DOWN (nidaqmx.constants.ResistorState at- RADIANS_PER_SECOND
tribute), 37
(nidaqmx.constants.AngularVelocityUnits
PULL_UP (nidaqmx.constants.LogicLvlBehavior atattribute), 19
tribute), 32
RADIANS_PER_SECOND
PULL_UP (nidaqmx.constants.ResistorState attribute),
(nidaqmx.constants.UnitsPreScaled attribute),
37
46
PULSE (nidaqmx.constants.ExportAction attribute), 27
RAW (nidaqmx.constants.Language attribute), 30
PULSE_FREQ (nidaqmx.constants.UsageTypeCI at- raw_data_width (nidaqmx._task_modules.in_stream.InStream
tribute), 49
attribute), 223
PULSE_FREQUENCY (nidaqmx.constants.UsageTypeCO raw_data_width (nidaqmx._task_modules.out_stream.OutStream
attribute), 49
attribute), 228
PULSE_TICKS
(nidaqmx.constants.UsageTypeCI RawDataCompressionType (class in nidaqmx.constants),
attribute), 49
35
PULSE_TICKS (nidaqmx.constants.UsageTypeCO at- rdy_for_start_event_lvl_active_lvl
tribute), 49
(nidaqmx._task_modules.export_signals.ExportSignals
PULSE_TIME (nidaqmx.constants.UsageTypeCI atattribute), 218
tribute), 49
rdy_for_start_event_output_term
PULSE_TIME
(nidaqmx.constants.UsageTypeCO
(nidaqmx._task_modules.export_signals.ExportSignals
attribute), 49
attribute), 219
PULSE_WIDTH_DIGITAL
rdy_for_xfer_event_deassert_cond
(nidaqmx.constants.UsageTypeCI attribute), 49
(nidaqmx._task_modules.export_signals.ExportSignals
PULSE_WIDTH_DIGITAL_SEMI_PERIOD
attribute), 219
(nidaqmx.constants.UsageTypeCI attribute), 49 rdy_for_xfer_event_deassert_cond_custom_threshold
PULSE_WIDTH_DIGITAL_TWO_EDGE_SEPARATION
(nidaqmx._task_modules.export_signals.ExportSignals
(nidaqmx.constants.UsageTypeCI attribute), 49
attribute), 219
PXI (nidaqmx.constants.BusType attribute), 22
rdy_for_xfer_event_lvl_active_lvl
pxi_chassis_num (nidaqmx.system.device.Device at(nidaqmx._task_modules.export_signals.ExportSignals
tribute), 103
attribute), 219
pxi_slot_num (nidaqmx.system.device.Device attribute), rdy_for_xfer_event_output_term
103
(nidaqmx._task_modules.export_signals.ExportSignals
PXIE (nidaqmx.constants.BusType attribute), 22
attribute), 219
read()
(nidaqmx._task_modules.in_stream.InStream
Q
method), 223
read() (nidaqmx.task.Task method), 113
QUARTER_BRIDGE (nidaqmx.constants.BridgeConfiguration
read_all_avail_samp (nidaqmx._task_modules.in_stream.InStream
attribute), 20
QUARTER_BRIDGE_I (nidaqmx.constants.StrainGageBridgeType attribute), 224
read_int16() (nidaqmx.stream_readers.AnalogUnscaledReader
attribute), 40
method), 59
QUARTER_BRIDGE_II
(nidaqmx.constants.StrainGageBridgeType
Index

291

NI-DAQmx Python API Documentation, Release 0.5.0

read_int32() (nidaqmx.stream_readers.AnalogUnscaledReader
method), 75
method), 60
read_one_sample_one_line()
read_many_sample() (nidaqmx.stream_readers.AnalogMultiChannelReader
(nidaqmx.stream_readers.DigitalSingleChannelReader
method), 57
method), 71
read_many_sample() (nidaqmx.stream_readers.AnalogSingleChannelReader
read_one_sample_port_byte()
method), 56
(nidaqmx.stream_readers.DigitalMultiChannelReader
read_many_sample_double()
method), 76
(nidaqmx.stream_readers.CounterReader
read_one_sample_port_byte()
method), 63
(nidaqmx.stream_readers.DigitalSingleChannelReader
read_many_sample_port_byte()
method), 71
(nidaqmx.stream_readers.DigitalMultiChannelReader
read_one_sample_port_uint16()
method), 72
(nidaqmx.stream_readers.DigitalMultiChannelReader
read_many_sample_port_byte()
method), 76
(nidaqmx.stream_readers.DigitalSingleChannelReader
read_one_sample_port_uint16()
method), 68
(nidaqmx.stream_readers.DigitalSingleChannelReader
read_many_sample_port_uint16()
method), 71
(nidaqmx.stream_readers.DigitalMultiChannelReader
read_one_sample_port_uint32()
method), 73
(nidaqmx.stream_readers.DigitalMultiChannelReader
read_many_sample_port_uint16()
method), 77
(nidaqmx.stream_readers.DigitalSingleChannelReader
read_one_sample_port_uint32()
method), 69
(nidaqmx.stream_readers.DigitalSingleChannelReader
read_many_sample_port_uint32()
method), 71
(nidaqmx.stream_readers.DigitalMultiChannelReader
read_one_sample_pulse_frequency()
method), 74
(nidaqmx.stream_readers.CounterReader
read_many_sample_port_uint32()
method), 67
(nidaqmx.stream_readers.DigitalSingleChannelReader
read_one_sample_pulse_ticks()
method), 70
(nidaqmx.stream_readers.CounterReader
read_many_sample_pulse_frequency()
method), 67
(nidaqmx.stream_readers.CounterReader
read_one_sample_pulse_time()
method), 63
(nidaqmx.stream_readers.CounterReader
read_many_sample_pulse_ticks()
method), 67
(nidaqmx.stream_readers.CounterReader
read_one_sample_uint32()
method), 64
(nidaqmx.stream_readers.CounterReader
read_many_sample_pulse_time()
method), 68
(nidaqmx.stream_readers.CounterReader
read_uint16() (nidaqmx.stream_readers.AnalogUnscaledReader
method), 65
method), 60
read_many_sample_uint32()
read_uint32() (nidaqmx.stream_readers.AnalogUnscaledReader
(nidaqmx.stream_readers.CounterReader
method), 61
method), 66
readall() (nidaqmx._task_modules.in_stream.InStream
read_one_sample() (nidaqmx.stream_readers.AnalogMultiChannelReader
method), 224
method), 58
readinto() (nidaqmx._task_modules.in_stream.InStream
read_one_sample() (nidaqmx.stream_readers.AnalogSingleChannelReader
method), 225
method), 57
ReadRelativeTo (class in nidaqmx.constants), 36
read_one_sample_double()
RECTANGULAR (nidaqmx.constants.StrainGageRosetteType
(nidaqmx.stream_readers.CounterReader
attribute), 41
method), 67
ref_clk_rate (nidaqmx._task_modules.timing.Timing atread_one_sample_multi_line()
tribute), 234
(nidaqmx.stream_readers.DigitalMultiChannelReader
ref_clk_src (nidaqmx._task_modules.timing.Timing atmethod), 75
tribute), 234
read_one_sample_multi_line()
ref_trig_output_term (nidaqmx._task_modules.export_signals.ExportSignal
(nidaqmx.stream_readers.DigitalSingleChannelReader
attribute), 219
method), 70
ref_trig_pulse_polarity (nidaqmx._task_modules.export_signals.ExportSign
read_one_sample_one_line()
attribute), 219
(nidaqmx.stream_readers.DigitalMultiChannelReader
REFERENCE (nidaqmx.constants.TriggerUsage at-

292

Index

NI-DAQmx Python API Documentation, Release 0.5.0

tribute), 45
attribute), 37
reference_trigger (nidaqmx._task_modules.triggers.TriggersRIGHT (nidaqmx.constants.DataJustification attribute),
attribute), 236
24
REFERENCE_TRIGGER
RISING (nidaqmx.constants.Edge attribute), 26
(nidaqmx.constants.ReadRelativeTo attribute), RISING (nidaqmx.constants.Slope attribute), 40
36
ROSETTE_STRAIN_GAGE
REFERENCE_TRIGGER (nidaqmx.constants.Signal at(nidaqmx.constants.UsageTypeAI attribute), 47
tribute), 39
RPM (nidaqmx.constants.AngularVelocityUnits atReferenceTrigger
(class
in
tribute), 20
nidaqmx._task_modules.triggering.reference_trigger),
RPM (nidaqmx.constants.UnitsPreScaled attribute), 46
240
RSE (nidaqmx.constants.TerminalConfiguration atregen_mode (nidaqmx._task_modules.out_stream.OutStream
tribute), 43
attribute), 228
RTDType (class in nidaqmx.constants), 35
RegenerationMode (class in nidaqmx.constants), 36
RVDTSensitivityUnits (class in nidaqmx.constants), 35
register_done_event() (nidaqmx.task.Task method), 114
register_every_n_samples_acquired_into_buffer_event() S
(nidaqmx.task.Task method), 115
S (nidaqmx.constants.ThermocoupleType attribute), 43
register_every_n_samples_transferred_from_buffer_event() S_SERIES_DAQ (nidaqmx.constants.ProductCategory
(nidaqmx.task.Task method), 115
attribute), 35
register_signal_event() (nidaqmx.task.Task method), 116 samp_clk_active_edge (nidaqmx._task_modules.timing.Timing
relative_to (nidaqmx._task_modules.in_stream.InStream
attribute), 234
attribute), 225
samp_clk_delay_offset (nidaqmx._task_modules.export_signals.ExportSign
relative_to (nidaqmx._task_modules.out_stream.OutStream
attribute), 219
attribute), 228
samp_clk_dig_fltr_enable
RelayPosition (class in nidaqmx.constants), 36
(nidaqmx._task_modules.timing.Timing
REMOTE (nidaqmx.constants.Sense attribute), 39
attribute), 234
remove_cdaq_sync_connection()
samp_clk_dig_fltr_min_pulse_width
(nidaqmx.system.system.System
method),
(nidaqmx._task_modules.timing.Timing
94
attribute), 234
REPEAT_LAST_SAMPLE
samp_clk_dig_fltr_timebase_rate
(nidaqmx.constants.SampClkOverrunBehavior
(nidaqmx._task_modules.timing.Timing
attribute), 37
attribute), 234
reserve_network_device()
samp_clk_dig_fltr_timebase_src
(nidaqmx.system.device.Device
method),
(nidaqmx._task_modules.timing.Timing
104
attribute), 234
RESERVED_FOR_ROUTING_CHANNEL
samp_clk_dig_sync_enable
(nidaqmx.constants.SwitchChannelUsage
(nidaqmx._task_modules.timing.Timing
attribute), 41
attribute), 234
reset_device() (nidaqmx.system.device.Device method), samp_clk_max_rate (nidaqmx._task_modules.timing.Timing
104
attribute), 234
RESET_TIMER (nidaqmx.constants.WDTTaskAction samp_clk_output_behavior
attribute), 50
(nidaqmx._task_modules.export_signals.ExportSignals
reset_timer() (nidaqmx.system.watchdog.WatchdogTask
attribute), 219
method), 111
samp_clk_output_term (nidaqmx._task_modules.export_signals.ExportSign
RESISTANCE (nidaqmx.constants.UsageTypeAI atattribute), 219
tribute), 47
samp_clk_overrun_behavior
ResistanceConfiguration (class in nidaqmx.constants), 36
(nidaqmx._task_modules.timing.Timing
ResistanceUnits (class in nidaqmx.constants), 36
attribute), 234
ResistorState (class in nidaqmx.constants), 37
samp_clk_pulse_polarity
ResolutionType (class in nidaqmx.constants), 37
(nidaqmx._task_modules.export_signals.ExportSignals
retriggerable (nidaqmx._task_modules.triggering.start_trigger.StartTrigger
attribute), 219
attribute), 247
samp_clk_rate (nidaqmx._task_modules.timing.Timing
RETURN_SENTINEL_VALUE
attribute), 234
(nidaqmx.constants.SampClkOverrunBehavior

Index

293

NI-DAQmx Python API Documentation, Release 0.5.0

samp_clk_src (nidaqmx._task_modules.timing.Timing
attribute), 51
attribute), 234
SAMPLES_ONLY (nidaqmx.constants.WaveformAttributes
samp_clk_term (nidaqmx._task_modules.timing.Timing
attribute), 51
attribute), 234
SAMPLES_TIMING_AND_ATTRIBUTES
samp_clk_timebase_active_edge
(nidaqmx.constants.WaveformAttributes
(nidaqmx._task_modules.timing.Timing
attribute), 51
attribute), 234
SampleTimingType (class in nidaqmx.constants), 37
samp_clk_timebase_div (nidaqmx._task_modules.timing.Timing
save() (nidaqmx._task_modules.channels.ai_channel.AIChannel
attribute), 234
method), 130
samp_clk_timebase_master_timebase_div
save() (nidaqmx._task_modules.channels.ao_channel.AOChannel
(nidaqmx._task_modules.timing.Timing
method), 134
attribute), 235
save() (nidaqmx._task_modules.channels.channel.Channel
samp_clk_timebase_output_term
method), 118
(nidaqmx._task_modules.export_signals.ExportSignals
save() (nidaqmx._task_modules.channels.ci_channel.CIChannel
attribute), 219
method), 148
samp_clk_timebase_rate (nidaqmx._task_modules.timing.Timing
save() (nidaqmx._task_modules.channels.co_channel.COChannel
attribute), 235
method), 151
samp_clk_timebase_src (nidaqmx._task_modules.timing.Timing
save() (nidaqmx._task_modules.channels.di_channel.DIChannel
attribute), 235
method), 154
samp_clk_timebase_term
save() (nidaqmx._task_modules.channels.do_channel.DOChannel
(nidaqmx._task_modules.timing.Timing
method), 156
attribute), 235
save() (nidaqmx.scale.Scale method), 55
samp_clk_underflow_behavior
save() (nidaqmx.task.Task method), 116
(nidaqmx._task_modules.timing.Timing
SAWTOOTH (nidaqmx.constants.FuncGenType atattribute), 235
tribute), 29
samp_clk_write_wfm_use_initial_wfm_dt
SC_EXPRESS (nidaqmx.constants.ProductCategory at(nidaqmx._task_modules.timing.Timing
tribute), 34
attribute), 235
SC_SERIES_DAQ (nidaqmx.constants.ProductCategory
samp_quant_samp_mode
attribute), 35
(nidaqmx._task_modules.timing.Timing
Scale (class in nidaqmx.scale), 52
attribute), 235
scale_names (nidaqmx.system._collections.persisted_scale_collection.Persis
samp_quant_samp_per_chan
attribute), 97
(nidaqmx._task_modules.timing.Timing
scale_type (nidaqmx.scale.Scale attribute), 56
attribute), 235
scaled_units (nidaqmx.scale.Scale attribute), 56
samp_timing_engine (nidaqmx._task_modules.timing.Timing
scales (nidaqmx.system.system.System attribute), 94
attribute), 235
ScaleType (class in nidaqmx.constants), 38
samp_timing_type (nidaqmx._task_modules.timing.Timing SCANNABLE_CHANNEL
attribute), 235
(nidaqmx.constants.CJCSource
attribute),
SampClkOverrunBehavior (class in nidaqmx.constants),
22
37
ScanRepeatMode (class in nidaqmx.constants), 38
SAMPLE_CLOCK (nidaqmx.constants.SampleTimingTypeSCC (nidaqmx.constants.BusType attribute), 22
attribute), 38
SCC_CONNECTOR_BLOCK
SAMPLE_CLOCK (nidaqmx.constants.Signal attribute),
(nidaqmx.constants.ProductCategory attribute),
39
34
SAMPLE_CLOCK_PERIODS
SCC_MODULE (nidaqmx.constants.ProductCategory at(nidaqmx.constants.DigitalWidthUnits
attribute), 34
tribute), 25
SCXI (nidaqmx.constants.BusType attribute), 22
SAMPLE_COMPLETE (nidaqmx.constants.Signal at- SCXI1124Range (class in nidaqmx.constants), 37
tribute), 39
SCXI_MODULE (nidaqmx.constants.ProductCategory
SAMPLE_TIMEBASE (nidaqmx.constants.MIOAIConvertTimebaseSource
attribute), 34
attribute), 32
SECONDS
(nidaqmx.constants.DigitalWidthUnits
SampleInputDataWhen (class in nidaqmx.constants), 37
attribute), 25
SAMPLES_AND_TIMING
SECONDS (nidaqmx.constants.TimeUnits attribute), 43
(nidaqmx.constants.WaveformAttributes
SECONDS
(nidaqmx.constants.UnitsPreScaled
at-

294

Index

NI-DAQmx Python API Documentation, Release 0.5.0

tribute), 46
method), 111
self_test_device()
(nidaqmx.system.device.Device start() (nidaqmx.task.Task method), 117
method), 104
start_new_file() (nidaqmx._task_modules.in_stream.InStream
Sense (class in nidaqmx.constants), 38
method), 225
set_analog_power_up_states()
start_trig_output_term (nidaqmx._task_modules.export_signals.ExportSigna
(nidaqmx.system.system.System
method),
attribute), 219
94
start_trig_pulse_polarity (nidaqmx._task_modules.export_signals.ExportSig
set_analog_power_up_states_with_output_type()
attribute), 219
(nidaqmx.system.system.System
method), start_trigger (nidaqmx._task_modules.triggers.Triggers
95
attribute), 236
set_digital_logic_family_power_up_state()
START_TRIGGER (nidaqmx.constants.Signal attribute),
(nidaqmx.system.system.System
method),
39
95
StartTrigger (class in nidaqmx._task_modules.triggering.start_trigger),
set_digital_power_up_states()
244
(nidaqmx.system.system.System
method), stop()
(nidaqmx.system.watchdog.WatchdogTask
95
method), 111
set_digital_pull_up_pull_down_states()
stop() (nidaqmx.task.Task method), 117
(nidaqmx.system.system.System
method), STRAIN (nidaqmx.constants.StrainUnits attribute), 41
95
STRAIN (nidaqmx.constants.UnitsPreScaled attribute),
SEVENTY_FIVE_OHMS
46
(nidaqmx.constants.Impedance1
attribute), STRAIN_STRAIN_GAGE
29
(nidaqmx.constants.UsageTypeAI attribute), 47
ShuntCalSelect (class in nidaqmx.constants), 39
StrainGageBridgeType (class in nidaqmx.constants), 40
ShuntElementLocation (class in nidaqmx.constants), 39
StrainGageRosetteMeasurementType
(class
in
ShuntResistorSelect (class in nidaqmx.constants), 39
nidaqmx.constants), 41
Signal (class in nidaqmx.constants), 39
StrainGageRosetteType (class in nidaqmx.constants), 41
SignalModifiers (class in nidaqmx.constants), 40
StrainUnits (class in nidaqmx.constants), 41
simultaneous_ao_enable (nidaqmx._task_modules.timing.Timing
SWITCH_BLOCK (nidaqmx.constants.BusType atattribute), 235
tribute), 22
SINE (nidaqmx.constants.FuncGenType attribute), 29
SwitchChannelUsage (class in nidaqmx.constants), 41
SIX_WIRE (nidaqmx.constants.ACExcitWireMode at- SWITCHES
(nidaqmx.constants.ProductCategory
tribute), 17
attribute), 35
SLAVE (nidaqmx.constants.SyncType attribute), 42
sync_clk_interval (nidaqmx._task_modules.timing.Timing
SLEEP (nidaqmx.constants.WaitMode attribute), 50
attribute), 235
sleep_time (nidaqmx._task_modules.in_stream.InStream sync_pulse_event_output_term
attribute), 225
(nidaqmx._task_modules.export_signals.ExportSignals
sleep_time (nidaqmx._task_modules.out_stream.OutStream
attribute), 219
attribute), 228
sync_pulse_min_delay_to_start
Slope (class in nidaqmx.constants), 40
(nidaqmx._task_modules.timing.Timing
SOFTWARE (nidaqmx.constants.TriggerType attribute),
attribute), 235
44
sync_pulse_reset_delay (nidaqmx._task_modules.timing.Timing
SoftwareTrigger (class in nidaqmx.constants), 40
attribute), 235
SOUND_PRESSURE_MICROPHONE
sync_pulse_reset_time (nidaqmx._task_modules.timing.Timing
(nidaqmx.constants.UsageTypeAI attribute), 47
attribute), 236
SoundPressureUnits (class in nidaqmx.constants), 40
sync_pulse_src (nidaqmx._task_modules.timing.Timing
SOURCE_CHANNEL (nidaqmx.constants.SwitchChannelUsage
attribute), 236
attribute), 41
sync_pulse_sync_time (nidaqmx._task_modules.timing.Timing
SourceSelection (class in nidaqmx.constants), 40
attribute), 236
space_avail (nidaqmx._task_modules.out_stream.OutStreamsync_pulse_term (nidaqmx._task_modules.timing.Timing
attribute), 228
attribute), 236
SQUARE (nidaqmx.constants.FuncGenType attribute), sync_type (nidaqmx._task_modules.triggers.Triggers at29
tribute), 236
START (nidaqmx.constants.TriggerUsage attribute), 45
SyncType (class in nidaqmx.constants), 42
start()
(nidaqmx.system.watchdog.WatchdogTask System (class in nidaqmx.system.system), 91

Index

295

NI-DAQmx Python API Documentation, Release 0.5.0

TEMPERATURE_BUILT_IN_SENSOR
(nidaqmx.constants.UsageTypeAI attribute), 48
T (nidaqmx.constants.ThermocoupleType attribute), 43
TEMPERATURE_RTD
(nidaqmx.constants.UsageTypeAI
TAB_DELIMITED (nidaqmx.constants.TaskStringFormat
attribute),
48
attribute), 42
TEMPERATURE_THERMISTOR
TABLE (nidaqmx.constants.ScaleType attribute), 38
(nidaqmx.constants.UsageTypeAI attribute), 48
table_pre_scaled_vals (nidaqmx.scale.Scale attribute), 56
TEMPERATURE_THERMOCOUPLE
table_scaled_vals (nidaqmx.scale.Scale attribute), 56
(nidaqmx.constants.UsageTypeAI attribute), 48
Task (class in nidaqmx.task), 112
TemperatureUnits
(class in nidaqmx.constants), 42
TASK_ABORT (nidaqmx.constants.TaskMode attribute),
TEN_G_OHMS
(nidaqmx.constants.Impedance1 at42
tribute),
29
TASK_COMMIT (nidaqmx.constants.TaskMode atTEN_M_HZ_REF_CLOCK (nidaqmx.constants.Signal
tribute), 42
attribute), 39
task_names (nidaqmx.system._collections.persisted_task_collection.PersistedTaskCollection
term
(nidaqmx._task_modules.triggering.arm_start_trigger.ArmStartTrigger
attribute), 97
attribute), 237
TASK_RESERVE (nidaqmx.constants.TaskMode atterm
(nidaqmx._task_modules.triggering.pause_trigger.PauseTrigger
tribute), 42
attribute), 239
TASK_START (nidaqmx.constants.TaskMode attribute),
term
(nidaqmx._task_modules.triggering.reference_trigger.ReferenceTrigge
42
attribute), 244
TASK_STOP (nidaqmx.constants.TaskMode attribute),
term
(nidaqmx._task_modules.triggering.start_trigger.StartTrigger
42
attribute), 247
TASK_UNRESERVE (nidaqmx.constants.TaskMode atTerminalConfiguration
(class in nidaqmx.constants), 43
tribute), 42
terminals
(nidaqmx.system.device.Device
attribute), 104
TASK_VERIFY
(nidaqmx.constants.TaskMode
atThermocoupleType
(class
in
nidaqmx.constants),
43
tribute), 42
THREE_POINT_THREE_V
TaskMode (class in nidaqmx.constants), 42
(nidaqmx.constants.LogicFamily
attribute),
tasks (nidaqmx.system.system.System attribute), 96
32
TaskStringFormat (class in nidaqmx.constants), 42
THREE_WIRE (nidaqmx.constants.ResistanceConfiguration
TCPIP (nidaqmx.constants.BusType attribute), 22
attribute), 36
tcpip_ethernet_ip (nidaqmx.system.device.Device atTICKS (nidaqmx.constants.AngleUnits attribute), 19
tribute), 104
tcpip_hostname (nidaqmx.system.device.Device at- TICKS (nidaqmx.constants.DigitalWidthUnits attribute),
25
tribute), 104
tcpip_wireless_ip (nidaqmx.system.device.Device at- TICKS (nidaqmx.constants.FrequencyUnits attribute), 29
TICKS (nidaqmx.constants.LengthUnits attribute), 31
tribute), 104
TICKS (nidaqmx.constants.TimeUnits attribute), 43
TEDS (nidaqmx.constants.UsageTypeAI attribute), 48
TICKS (nidaqmx.constants.UnitsPreScaled attribute), 46
teds_bit_stream (nidaqmx.system.physical_channel.PhysicalChannel
TIME_GPS (nidaqmx.constants.UsageTypeCI attribute),
attribute), 106
49
teds_mfg_id (nidaqmx.system.physical_channel.PhysicalChannel
timeout (nidaqmx._task_modules.in_stream.InStream atattribute), 106
teds_model_num (nidaqmx.system.physical_channel.PhysicalChanneltribute), 225
timeout (nidaqmx._task_modules.out_stream.OutStream
attribute), 106
teds_serial_num (nidaqmx.system.physical_channel.PhysicalChannel attribute), 228
timeout (nidaqmx.system.watchdog.WatchdogTask atattribute), 106
teds_template_ids (nidaqmx.system.physical_channel.PhysicalChanneltribute), 111
TimeUnits (class in nidaqmx.constants), 43
attribute), 106
Timing (class in nidaqmx._task_modules.timing), 229
teds_version_letter (nidaqmx.system.physical_channel.PhysicalChannel
timing (nidaqmx.task.Task attribute), 117
attribute), 106
TIO_SERIES (nidaqmx.constants.ProductCategory atteds_version_num (nidaqmx.system.physical_channel.PhysicalChannel
tribute), 35
attribute), 106
TOGGLE
(nidaqmx.constants.ExportAction attribute), 27
tedshwteds_supported (nidaqmx.system.device.Device
TOP_TASK_AND_ERROR
attribute), 104
(nidaqmx.constants.OverflowBehavior
atTEDSUnits (class in nidaqmx.constants), 42
tribute),
33
TEE (nidaqmx.constants.StrainGageRosetteType atTORQUE_BRIDGE (nidaqmx.constants.UsageTypeAI
tribute), 41
296

Index

NI-DAQmx Python API Documentation, Release 0.5.0

attribute), 48
UNKNOWN
(nidaqmx.constants.ProductCategory
TorqueUnits (class in nidaqmx.constants), 44
attribute), 35
total_samp_per_chan_acquired
unreserve_network_device()
(nidaqmx._task_modules.in_stream.InStream
(nidaqmx.system.device.Device
method),
attribute), 226
104
total_samp_per_chan_generated
UsageTypeAI (class in nidaqmx.constants), 47
(nidaqmx._task_modules.out_stream.OutStream UsageTypeAO (class in nidaqmx.constants), 48
attribute), 228
UsageTypeCI (class in nidaqmx.constants), 48
TRANSFERRED_FROM_BUFFER
UsageTypeCO (class in nidaqmx.constants), 49
(nidaqmx.constants.EveryNSamplesEventType USB (nidaqmx.constants.BusType attribute), 22
attribute), 26
USB_BULK (nidaqmx.constants.DataTransferActiveTransferMode
TRIANGLE (nidaqmx.constants.FuncGenType attribute),
attribute), 25
29
USBDAQ
(nidaqmx.constants.ProductCategory
attrig_type (nidaqmx._task_modules.triggering.arm_start_trigger.ArmStartTrigger
tribute), 35
attribute), 237
USE_AC (nidaqmx.constants.ExcitationDCorAC attrig_type (nidaqmx._task_modules.triggering.handshake_trigger.HandshakeTrigger
tribute), 26
attribute), 237
USE_CURRENT (nidaqmx.constants.ExcitationVoltageOrCurrent
trig_type (nidaqmx._task_modules.triggering.pause_trigger.PauseTrigger
attribute), 27
attribute), 240
USE_DC (nidaqmx.constants.ExcitationDCorAC attrig_type (nidaqmx._task_modules.triggering.reference_trigger.ReferenceTrigger
tribute), 27
attribute), 244
USE_VOLTAGE (nidaqmx.constants.ExcitationVoltageOrCurrent
trig_type (nidaqmx._task_modules.triggering.start_trigger.StartTriggerattribute), 27
attribute), 247
USER_PROVIDED (nidaqmx.constants.BridgeShuntCalSource
Triggers (class in nidaqmx._task_modules.triggers), 236
attribute), 21
triggers (nidaqmx.task.Task attribute), 117
V
TriggerType (class in nidaqmx.constants), 44
TriggerUsage (class in nidaqmx.constants), 44
VELOCITY_ANGULAR_ENCODER
TRISTATE (nidaqmx.constants.Level attribute), 31
(nidaqmx.constants.UsageTypeCI attribute), 49
TRISTATE
(nidaqmx.constants.PowerUpStates
at- VELOCITY_IEPE_SENSOR
tribute), 34
(nidaqmx.constants.UsageTypeAI attribute), 48
tristate_output_term() (nidaqmx.system.system.System VELOCITY_LINEAR_ENCODER
method), 96
(nidaqmx.constants.UsageTypeCI attribute), 49
TWENTY_M_HZ_TIMEBASE
VelocityIEPESensorSensitivityUnits
(class
in
(nidaqmx.constants.MIOAIConvertTimebaseSource
nidaqmx.constants), 49
attribute), 32
VelocityUnits (class in nidaqmx.constants), 49
TWENTY_M_HZ_TIMEBASE_CLOCK
verify_array_shape (nidaqmx.stream_readers.AnalogMultiChannelReader
(nidaqmx.constants.Signal attribute), 40
attribute), 58
TWO_POINT_FIVE_V (nidaqmx.constants.LogicFamily verify_array_shape (nidaqmx.stream_readers.AnalogSingleChannelReader
attribute), 32
attribute), 57
TWO_POINT_LINEAR (nidaqmx.constants.ScaleType verify_array_shape (nidaqmx.stream_readers.AnalogUnscaledReader
attribute), 38
attribute), 62
TWO_PULSE_COUNTING
verify_array_shape (nidaqmx.stream_readers.CounterReader
(nidaqmx.constants.EncoderType attribute), 26
attribute), 68
TWO_WIRE (nidaqmx.constants.ResistanceConfiguration verify_array_shape (nidaqmx.stream_readers.DigitalMultiChannelReader
attribute), 36
attribute), 77
verify_array_shape (nidaqmx.stream_readers.DigitalSingleChannelReader
U
attribute), 72
UNCONSTRAINED (nidaqmx.constants.ConstrainedGenMode
verify_array_shape (nidaqmx.stream_writers.AnalogMultiChannelWriter
attribute), 23
attribute), 78
UnderflowBehavior (class in nidaqmx.constants), 45
verify_array_shape (nidaqmx.stream_writers.AnalogSingleChannelWriter
unflatten_channel_string() (in module nidaqmx.utils),
attribute), 77
249
verify_array_shape (nidaqmx.stream_writers.AnalogUnscaledWriter
UnitsPreScaled (class in nidaqmx.constants), 45
attribute), 80
UNKNOWN (nidaqmx.constants.BusType attribute), 22
Index

297

NI-DAQmx Python API Documentation, Release 0.5.0

verify_array_shape (nidaqmx.stream_writers.CounterWriterWatchdogCOExpirState (class in nidaqmx.constants), 50
attribute), 82
WatchdogTask (class in nidaqmx.system.watchdog), 109
verify_array_shape (nidaqmx.stream_writers.DigitalMultiChannelWriter
WaveformAttributes (class in nidaqmx.constants), 51
attribute), 88
WDTTaskAction (class in nidaqmx.constants), 50
verify_array_shape (nidaqmx.stream_writers.DigitalSingleChannelWriter
WHEN_ACQUISITION_COMPLETE
attribute), 85
(nidaqmx.constants.InputDataTransferCondition
VOLTAGE (nidaqmx.constants.AOPowerUpOutputBehavior
attribute), 30
attribute), 18
WindowTriggerCondition1 (class in nidaqmx.constants),
VOLTAGE
(nidaqmx.constants.CalibrationMode2
51
attribute), 22
WindowTriggerCondition2 (class in nidaqmx.constants),
VOLTAGE (nidaqmx.constants.UsageTypeAI attribute),
51
48
write() (nidaqmx._task_modules.out_stream.OutStream
VOLTAGE (nidaqmx.constants.UsageTypeAO attribute),
method), 228
48
write() (nidaqmx.task.Task method), 117
VOLTAGE (nidaqmx.constants.WatchdogAOExpirState write_int16() (nidaqmx.stream_writers.AnalogUnscaledWriter
attribute), 50
method), 80
VOLTAGE_ACRMS (nidaqmx.constants.UsageTypeAI write_int32() (nidaqmx.stream_writers.AnalogUnscaledWriter
attribute), 48
method), 80
VOLTAGE_CUSTOM_WITH_EXCITATION
write_many_sample() (nidaqmx.stream_writers.AnalogMultiChannelWriter
(nidaqmx.constants.UsageTypeAI attribute), 48
method), 79
VoltageUnits (class in nidaqmx.constants), 49
write_many_sample() (nidaqmx.stream_writers.AnalogSingleChannelWrite
VOLTS (nidaqmx.constants.UnitsPreScaled attribute), 47
method), 77
VOLTS (nidaqmx.constants.VoltageUnits attribute), 50
write_many_sample_port_byte()
VOLTS_PER_G (nidaqmx.constants.AccelSensitivityUnits
(nidaqmx.stream_writers.DigitalMultiChannelWriter
attribute), 18
method), 88
VOLTS_PER_VOLT (nidaqmx.constants.BridgeElectricalUnits
write_many_sample_port_byte()
attribute), 20
(nidaqmx.stream_writers.DigitalSingleChannelWriter
VOLTS_PER_VOLT (nidaqmx.constants.UnitsPreScaled
method), 85
attribute), 47
write_many_sample_port_uint16()
VOLTS_PER_VOLTS (nidaqmx.constants.BridgeUnits
(nidaqmx.stream_writers.DigitalMultiChannelWriter
attribute), 21
method), 88
write_many_sample_port_uint16()
W
(nidaqmx.stream_writers.DigitalSingleChannelWriter
method), 85
WAIT_FOR_HANDSHAKE_TRIGGER_ASSERT
write_many_sample_port_uint32()
(nidaqmx.constants.HandshakeStartCondition
(nidaqmx.stream_writers.DigitalMultiChannelWriter
attribute), 29
method), 89
WAIT_FOR_HANDSHAKE_TRIGGER_DEASSERT
write_many_sample_port_uint32()
(nidaqmx.constants.HandshakeStartCondition
(nidaqmx.stream_writers.DigitalSingleChannelWriter
attribute), 29
method), 86
WAIT_FOR_INTERRUPT
(nidaqmx.constants.WaitMode
attribute), write_many_sample_pulse_frequency()
(nidaqmx.stream_writers.CounterWriter
50
method), 82
wait_mode (nidaqmx._task_modules.in_stream.InStream
write_many_sample_pulse_ticks()
attribute), 226
(nidaqmx.stream_writers.CounterWriter
wait_mode (nidaqmx._task_modules.out_stream.OutStream
method), 82
attribute), 228
write_many_sample_pulse_time()
wait_until_done() (nidaqmx.task.Task method), 117
(nidaqmx.stream_writers.CounterWriter
WaitMode (class in nidaqmx.constants), 50
method), 83
watchdog_expired_event_output_term
write_one_sample()
(nidaqmx.stream_writers.AnalogMultiChannelWriter
(nidaqmx._task_modules.export_signals.ExportSignals
method),
79
attribute), 219
write_one_sample() (nidaqmx.stream_writers.AnalogSingleChannelWriter
WATCHDOG_TIMER_EXPIRED_EVENT
method), 78
(nidaqmx.constants.Signal attribute), 40
write_one_sample_multi_line()
WatchdogAOExpirState (class in nidaqmx.constants), 50
298

Index

NI-DAQmx Python API Documentation, Release 0.5.0

(nidaqmx.stream_writers.DigitalMultiChannelWriter
WriteRelativeTo (class in nidaqmx.constants), 51
method), 89
X
write_one_sample_multi_line()
(nidaqmx.stream_writers.DigitalSingleChannelWriter
X_1 (nidaqmx.constants.EncoderType attribute), 26
method), 86
X_2 (nidaqmx.constants.EncoderType attribute), 26
write_one_sample_one_line()
X_4 (nidaqmx.constants.EncoderType attribute), 26
(nidaqmx.stream_writers.DigitalMultiChannelWriter
X_SERIES_DAQ (nidaqmx.constants.ProductCategory
method), 90
attribute), 35
write_one_sample_one_line()
(nidaqmx.stream_writers.DigitalSingleChannelWriter
Y
method), 86
YIELD (nidaqmx.constants.WaitMode attribute), 50
write_one_sample_port_byte()
(nidaqmx.stream_writers.DigitalMultiChannelWriter
Z
method), 90
ZERO_TO_FIVE_V (nidaqmx.constants.SCXI1124Range
write_one_sample_port_byte()
attribute), 37
(nidaqmx.stream_writers.DigitalSingleChannelWriter
ZERO_TO_ONE_V (nidaqmx.constants.SCXI1124Range
method), 87
attribute), 37
write_one_sample_port_uint16()
ZERO_TO_TEN_V (nidaqmx.constants.SCXI1124Range
(nidaqmx.stream_writers.DigitalMultiChannelWriter
attribute), 37
method), 90
ZERO_TO_TWENTY_M_A
write_one_sample_port_uint16()
(nidaqmx.constants.SCXI1124Range attribute),
(nidaqmx.stream_writers.DigitalSingleChannelWriter
37
method), 87
ZERO_VOLTS (nidaqmx.constants.AOIdleOutputBehavior
write_one_sample_port_uint32()
attribute), 18
(nidaqmx.stream_writers.DigitalMultiChannelWriter
ZERO_VOLTS_OR_AMPERES
method), 91
(nidaqmx.constants.ExcitationIdleOutputBehavior
write_one_sample_port_uint32()
attribute), 27
(nidaqmx.stream_writers.DigitalSingleChannelWriter
method), 87
write_one_sample_pulse_frequency()
(nidaqmx.stream_writers.CounterWriter
method), 83
write_one_sample_pulse_ticks()
(nidaqmx.stream_writers.CounterWriter
method), 84
write_one_sample_pulse_time()
(nidaqmx.stream_writers.CounterWriter
method), 84
WRITE_TO_EEPROM (nidaqmx.constants.WriteBasicTEDSOptions
attribute), 51
WRITE_TO_PROM (nidaqmx.constants.WriteBasicTEDSOptions
attribute), 51
write_to_teds_from_array()
(nidaqmx.system.physical_channel.PhysicalChannel
method), 106
write_to_teds_from_file()
(nidaqmx.system.physical_channel.PhysicalChannel
method), 107
write_uint16() (nidaqmx.stream_writers.AnalogUnscaledWriter
method), 81
write_uint32() (nidaqmx.stream_writers.AnalogUnscaledWriter
method), 81
WriteBasicTEDSOptions (class in nidaqmx.constants),
51

Index

299

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NI DAQmx Python API Ation Manual Nidaqmx

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