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Document Description | user manual (BT740 series) |
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Date Submitted | 2013-05-21 00:00:00 |
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Document Title | user manual (BT740 series) |
Document Creator | Microsoft® Word 2010 |
Document Author: | Administrator |
Smart Technology. Delivered.
Enhanced Class 1
Bluetooth v2.1 Module
USER’S GUIDE
VERSION 0.2
Part # BT740-SA, BT740-SC
Americas: +1-800-492-2320 Option 2
Europe: +44-1628-858-940
Hong Kong: +852-2923-0610
www.lairdtech.com/bluetooth
Enhanced Class 1 Bluetooth v2.1 Module
User’s Guide
REVISION HISTORY
Revision
Revision Date
Description
Version
0.1
12/0413
Initial release to CA
Version -.2
01/05/13
JK updates and DW regulatory
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CONN-GUIDE-BT740_v0.2
Enhanced Class 1 Bluetooth v2.1 Module
User’s Guide
Table of Contents
10
11
12
13
14
15
16
17
18
19
20
21
Overview and Key Features .................................................................................................. 4
Specifications ....................................................................................................................... 5
I/O Characteristics .............................................................................................................. 11
Functional Description ........................................................................................................ 12
AT Command Set ............................................................................................................... 15
S Registers ......................................................................................................................... 35
Error Codes ........................................................................................................................ 50
Multipoint Protocol .............................................................................................................. 53
Module Events .................................................................................................................. 118
HDP Profile Related Events .............................................................................................. 127
Debug Events ................................................................................................................... 128
Data Channels .................................................................................................................. 129
Multipoint Application Examples ....................................................................................... 134
AT Application Examples .................................................................................................. 152
Surface Mount Modules .................................................................................................... 182
FCC Regulatory Statements ............................................................................................. 184
EU Declarations of Conformity .......................................................................................... 190
Mechanical Details ............................................................................................................ 192
Ordering Information ......................................................................................................... 194
Bluetooth SIG Approvals................................................................................................... 195
Glossary of Terms ............................................................................................................ 197
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CONN-GUIDE-BT740_v0.2
Enhanced Class 1 Bluetooth v2.1 Module
User’s Guide
1 OVERVIEW AND KEY FEATURES
®
Every BT740 series Bluetooth module from Laird is designed to add robust, long-range Bluetooth data
connectivity to any device. Based on the market-leading Cambridge Silicon Radio (CSR) BC04 chipset,
BT740 modules provide exceptionally low power consumption with outstanding Class 1 range via 18 dBm
of transmit power. The modules support the latest Bluetooth Version 2.1 specification, including Secure
Simple Pairing (SSP), which improves security and enhances the ease of use for end customers. A broad
range of Bluetooth profiles such as Serial Port Profile (SPP) and other vital features make BT740
modules superior to other Bluetooth modules.
With a compact footprint of 15.29 x 28.71 mm, the modules deliver maximum range with a minimum size.
To ease integration, the modules are designed to support a separate power supply for I/O. Another
integration advantage is the inclusion of a complete Bluetooth protocol stack with support for multi-point
connections and numerous Bluetooth profiles, including SPP, Human Interface Device (HID) profile, and
Health Device Profile (HDP). BT740 modules fully qualify as a Bluetooth End Products, enabling
designers to integrate the modules in devices without the need for further Bluetooth qualification.
An integrated AT command processor interfaces to the host system over a serial port using an extensive
range of AT commands. The AT command set abstracts the Bluetooth protocol from the host application,
saving many months of programming and integration time. It provides extremely short integration times
for data-oriented Bluetooth applications.
Included firmware provides programming support for multi-point applications that use up to seven
simultaneous data connections to and from the robust BT740 module. A low-cost developer’s kit makes it
easy for an OEM to integrate the module and guarantees the fastest route to prototype and then mass
production.
Features & Benefits
Bluetooth v2.1 + EDR
External or internal antennas
Comprehensive AT interface for simple
programming
Alternate packet based interface for
complex programming and up to seven
simultaneous connections
Bluetooth EPL
Compact footprint
Class 1 output – 18 dBm
UART interface with GPIO, PCM, and ADC
lines
Industrial temperature range
Field proven firmware used on BTM44x
series of modules
Application Areas
Bluetooth® Profiles Supported
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Medical devices
ePOS terminals
Automotive diagnostic equipment
Barcode scanners
Industrial cable replacement
Serial Port Profile (SPP)
Human Interface Device (HID) profile host
and device supported
Health Device Profile (HDP): Agent
supported
IEEE Device Specialization
11073-10415 (Weight Scale)
IEEE Device Specialization
11073 - 10408 (Thermometer)
IEEE Device Specialization
11073 – 10417 (Glucose)
CONN-GUIDE-BT740_v0.2
Enhanced Class 1 Bluetooth v2.1 Module
User’s Guide
2 SPECIFICATIONS
2.1 Detailed Specifications
Table 2-1: Detailed specifications
Categories
Wireless
Specification
Host Interface
Profiles
Command
Interfaces
Audio
Feature
Bluetooth®
Frequency
Max Transmit Power
Implementation
V2.1 + EDR
2.402 - 2.480 GHz
Class 1
18 dBm from integrated antenna
18 dBm at UFL antenna connector
Better than -87 dBm (at 25° C)
>1000m
Up to 2.1 Mbps (over the air)
Circa 350 kbps
TX, RX, DCD, RI, DTR, DSR, CTS, RTS
Default 9600, n, 8, 1
From 1,200 to 921,600 bps
Receive Sensitivity
Range
Data Rates
UART Data Transfer Rate
UART
GPIO
ADC
PCM
SPP
HID
HDP
Operation Modes
8 configurable lines
2 lines, 8 bit resolution
4 lines – see Audio section
Serial Port Profile
Human Interface Device
Health Device Profile
AT Command Set
Multi-Point API – seven simultaneous
connections
Firmware Upgrade over UART
3 x PCM Channels @ 64 kpbs
SCO and eSCO
Configurable as master or slave
8 bit A-law
8 bit µ-law
13 bit linear
PCM Clock available when in slave mode
3.0 – 5.0 V
On-board regulators and brown-out detection
Idle Mode – TBC
Discoverable –TBC
Inquiry Mode – TBC
Connecting Mode – TBC
Connected Mode (No Data Transfer) – TBC
Connected Mode (Max Data Transfer) – TBC
Sniff Mode – TBC
Firmware Upgrade
Support
SCO Channels
PCM Interface
Supply Voltage
Supply
Power Consumption
Various Modes –
Typical values
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CONN-GUIDE-BT740_v0.2
Enhanced Class 1 Bluetooth v2.1 Module
User’s Guide
Categories
Antenna Options
Physical
Environmental
Miscellaneous
Development Tools
Approvals
Feature
Internal
Implementation
Multilayer ceramic - BT740-SA-xx
External
Connection via u.FL - BT740-SC-xx
Dimensions
Weight
Operating
Storage
Lead Free
Warranty
Development Kit
Bluetooth®
FCC / IC / CE
15.29 mm x 28.71 mm x 2.5 mm
1.5 g
-40°C to +85°C
-40°C to +85°C
Lead-free and RoHS compliant
1 Year
Development kit DVK-BT740 and software tools
End Product Listing (EPL)
All BT740 Series (to be completed)
1. DSR, DTR, RI and DCD are configurable either as GPIO or as modem control lines.
2.2 Hardware Specifications
Ceramic Chip
Antenna
Figure 2-1: Functional Block Diagram
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CONN-GUIDE-BT740_v0.2
Enhanced Class 1 Bluetooth v2.1 Module
User’s Guide
2.3 Pin Definitions
Table 2-2: Pin definitions
Pin
Signal
Description
Comment
GND
SPI_MOSI
SPI bus serial I/P
See Note 0
GPIO6
I/O for host
GPIO7
I/O for host
RESET
Module reset I/P
See Note 0
SPI_CLK
SPI bus clock I/P
See Note 0
PCM_CLK
PCM clock I/P
PCM_SYNC
PCM sync I/P
PCM_IN
PCM data I/P
10
PCM_OUT
PCM Data O/P
11
VCC_5VIN
3.0 V < VIN < 5.0 V
12
GND
13
VCC_3V3
3.3 V Monitor
14
Analogue 1
1.8 V max
15
GND
16
UART_DSR
UART_DSR I/P
17
UART_DCD
UART_DCD I/P or O/ P
18
GPIO_9
I/O for host
19
GPIO_8
I/O for host
20
GND
21
Analogue 00
1.8 V max
22
UART_RX
Receive data I/P
23
UART_TX
Transmit data O/P
24
UART_RTS
Request to Send O/P
25
UART_CTS
Clear to Send I/P
26
USB_D+
Not used for AT module variants
27
USB_D-
Not used for AT module variants
28
UART_RI
Ring Input or Output
29
GPIO_3/UART_DTR
I/O for host/UART_DTR
30
GPIO_5
I/O for host
31
GPIO_4
I/O for host
32
SPI_CSB
SPI bus chip select I/P
See Note 0
33
SPI_MISO
SPI bus serial O/P
See Note 0
34
GND
Only on uFL version
See Note 0
35
RF_OUT
Only on uFL version
See Note 0
36
GND
Only on uFL version
See Note 0
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See Note 0
CONN-GUIDE-BT740_v0.2
Enhanced Class 1 Bluetooth v2.1 Module
User’s Guide
Notes:
Unused pins may have internal connections and must not be connected.
Note 1: Pins 2, 6, 32, and 33 (SPI related) are only for Laird internal production purposes.
Note 2: Pins 34 - 36 are only for uFL connector version of module – BT740-SC
Note 3: Power-on-reset (power cycling and brown out consideration) – The reset circuitry within the
BT740 module incorporates a brown-out detector; this may simplify power supply design. The
BT740 reset line is an active low. Input debounced so must be low for more than 5 ms to cause
a reset. Upon the application of power, the Power On Reset circuit built into the module ensures
that the unit starts correctly. There is no need for an external power reset monitor.
Note 4: Power Supply Consideration – The power supply for the module should be a single voltage
source of VCC within the VCC_IN range of 3.0 V to 5.0 V. It must be able to provide sufficient
current in a transmit burst. This can rise to 200 mA. To limit dissipation it is recommended that
you use a voltage at the lower end of the range.
Note 5: The module includes regulators to provide local 3.3 V. This rail is accessible on pin 13 for
monitoring purposes only. Under no circumstances should this pin be used to source current.
Compatibility Note for Legacy Devices
If Reset compatibility is required with BTM402 and BTM404:
Reset logic must invert (on the host PCB) by using suitable BJT (MMBT3904) with collector
connected to Reset pin BT730 module pin 5. A fixed 10k Ohm pull-down resistor to ground (BJT
input) ensures that the BT730 module is out of reset for the condition when host has yet to control
the reset line.
Add a 10 k pull-up to the host PCB on the UART_RX, otherwise the module remains in deep sleep
if not driven to high.
Add a 10 k pull-down to the host PCB on the UART_CTS. If it is not connected (which we do not
recommend) then the default state for UART_CTS input asserts, meaning that it can send data out
of UART_TX line.
PIO lines can be configured through software to be either inputs or outputs with weak or strong pullups or pull-downs. At reset, all PIO lines configure as inputs with weak pull-downs.
UART_RX, UART_TX, UART_CTS, UART_RTS, UART_RI, UART_DCD, and UART_DSR are all
3.3 V level logic. For example, when RX and TX are idle they sit at 3.3 V. Conversely, for
handshaking pins CTS, RTS, RI, DCD, and DSR, a 0 V is treated as an assertion.
Pin 28 (UART_RI) is active low. It is normally 3.3 V. When a remote device initiates a connection,
this pin goes low. This means that when this pin converts to RS232 voltage levels it has the correct
voltage level for assertion.
Pin 17 (UART_DCD) is active low. It is normally 3.3 V. When a connection is live, this pin is low.
This means that when this pin converts to RS232 voltage levels it has the correct voltage level for
assertion.
Pin 16 (UART_DSR) is an input, with active low logic. It should be connected to the DTR output of
the host. When the BTM740 module is in high speed mode (see definition for S Register 507), the
host should assert this pin to ensure that the connection maintains. A deassertion means that the
connection should be dropped or an online command mode is being requested.
Pin 13 (VCC_3V3 monitor) may only be used for monitoring purposes. It must not be used as a
current source.
Access the GPIO pins by using S Registers 623 to 629.
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CONN-GUIDE-BT740_v0.2
Enhanced Class 1 Bluetooth v2.1 Module
User’s Guide
GPIO3 is also used for DTR output (active low). See S Registers 552 and 553.
Analogue 0 and 1 should not exceed 1.8 V and are accessible through S Registers 701 and 702.
2.4 Electrical Specifications
2.4.1 Absolute Maximum ratings
Absolute maximum ratings for supply voltage and voltages on digital and analogue pins of the module are
listed below.
WARNING: Exceeding the following values causes permanent damage to the device.
Parameter
Min
Max
Unit
Peak current of power supply
200
mA
Voltage at digital pins
-0.4
3.7
Voltage at POWER pin
2.9 *
6.0
2.4.2 Recommended Operating Parameters
2.4.2.1 Power Supply
Signal
Name
VCC_VIN
I/O
Voltage level
11
3.0 V to 5.0 V *
Typ 3.3 V
1, 12, 15,
20, 34, 36
GND
VCC_3V3
Note:
Pin No
13
Comments
Ityp = TBC mA?
6 Ground terminals to be attached in
parallel
3.3 V typical
For monitoring only. No current source
VCC_3V3 refers to internal voltage generated by the LDO inside the module (typically 3.3 V).
Internal LDO drop is 0.2 V. To achieve 3.3 V for VCC_3V3 requires VCC_IN of 3.5V. IO voltage
levels follow VCC_3V3.
2.4.2.2 Signal Levels for Interface, PCM, SPI, and GPIO
Signal Type
Signal level
Input
VILmin= -0.4V
VILmax=0.8V
VIHmin=2.3V
VIHmax=3.7V
Signal level at 0 mA load
VOLmax=0.2V
VOHmin=3.1V
Output
2.4.2.3 RS-232 Interface
Signal Name
UART_TX
Pin No
23
I/O
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Comments
CONN-GUIDE-BT740_v0.2
Enhanced Class 1 Bluetooth v2.1 Module
User’s Guide
Signal Name
UART_RX
UART_CTS
UART_RTS
UART_DSR
UART_DTR
UART_RI
UART_DCD
Pin No
22
25
24
16
29
28
17
I/O
I or O
I or O
Comments
Pin No
33
32
I/O
Comments
I/O
I or O
I or O
Comments
Shared with GPIO3
Direction may be programmed.
Direction may be programmed.
2.4.2.4 SPI Bus
Signal Name
SPI_MOSI
SPI_MISO
SPI_CSB
SPI_CLK
INTERNAL USE ONLY - Used to reprogram Flash in Laird
production.
2.4.2.5 PCM Interface
Signal Name
PCM_CLK
PCM_IN
PCM_SYNC
PCM_OUT
Pin No
10
If unused, keep pins open.
PCM output signals are tri-stated when there is not an active
SCO or eSCO connection.
2.4.2.6 General Purpose I/O and ADC
Signal Name
GPIO_3 - 9
Analogue0, Analogue1
Pin No
3, 4, 16,
17, 18,
19, 29,
30, 31
14, 21
I/O
I or O
Signal level
See Recommended
Operating Parameters
Comments
Range 0 – 1.8 V
8 bit
2.4.2.7 Miscellaneous
Signal Name
USB D-
Pin No
27
I/O
USB D+
26
RESET
Signal level
VILmax =0.3vdd_usb
VIHmin =0.7vdd_usb
VILmax =0.3vdd_usb
VIHmin =0.7vdd_usb
Comments
Normally inactive. Pull to GND
through 10 kΩ.
VILmax=1.0V
Active LOW. The Reset input
contains a 10 kΩ pull-up resistor
(internal to module).
VIHmin=2.3V
Normally inactive. Pull to GND
through 10 kΩ.
Terminology:
USB Signal Levels: vdd_usb refers to the internal voltage generated by the LDO regulator on the module,
typically 3.3 V. Hence 0.3vdd_usb and 0.7vdd_usb correspond to 1.0 V to 2.3 V. Achieving 3.3V for
vdd_usb requires VCC_IN of 3.5V. USB IO voltage levels follow VCC_3V3. Correct USB operation
requires vdd_usb on 3.1 V, which requires of VCC_IN of ~3.3V (0.2V LDO drop).
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CONN-GUIDE-BT740_v0.2
Enhanced Class 1 Bluetooth v2.1 Module
User’s Guide
3 I/O Characteristics
3.1 Power Consumption
The current drain from the VCC power input line is dependent on various factors. The three most
significant factors are the voltage level at VCC, UART baud rate, and the operating mode. The hardware
specification for the module allows for a voltage range of 3.0 to 5.0 at VCC. The unit includes a linear
regulator and tests have shown that there is no significant difference in current draw when VCC changes
within the operating limits. Tests have shown that where power dissipation is an issue, it is best to keep
VCC at the lower end of the range.
The UART baud rate has a bearing on power dissipation because, as is normal for digital electronics, the
power requirements increase linearly with increasing clocking frequencies. Because of this, higher baud
rates result in a higher current drain.
The significant operating modes are:
Idle
Waiting for a connection
Inquiring
Initiating a connection
Sniff
Connected
With connected mode, it is also relevant to differentiate between no data being transferred and when data
is being transferred at the maximum rate possible. The AT command set document describes how to
configure the module for optimal power performance.
3.2 Typical Current Consumption in mA
Table 3-1: Current Consumption
VCC = 3.8V, Baudrate = 9600bps
Typical Current (mA)
Range = >1 meters
Idle Mode, S512=1
TBC
Wait for Connection Or Discoverable Mode,
TBC
AT+BTP
S508=S510=640, S509=S511=320
Wait for Connection Or Discoverable Mode,
TBC
AT+BTP
S508=S510=1000, S509=S511=11
Inquiry Mode, AT+BTIN
TBC
Connecting Mode (ATDxxx)
TBC
Connected Mode (No Data Transfer)
TBC
Connected Mode (Max Data Transfer)
TBC
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CONN-GUIDE-BT740_v0.2
Enhanced Class 1 Bluetooth v2.1 Module
User’s Guide
4 FUNCTIONAL DESCRIPTION
The BT740 Bluetooth module is a self-contained Bluetooth product and requires only power to implement
full Bluetooth communication. The integrated, high performance antenna, together with the RF and baseband circuitry provides the Bluetooth wireless link and the UART interface provides a connection to the
host system.
The variety of interfaces and the AT command set allow the BT740 module to be used for a wide number
of long range wireless applications, from simple cable replacement to complex multipoint applications,
where multiple radio links are active at the same time.
The complexity and flexibility of configuration are made simple for the design engineer by the integration
of an extremely comprehensive set of AT commands, supplemented with a range of “S” registers which
are used for non-volatile storage of system parameters.
To provide the widest scope for integration a range of different physical host interfaces are provided.
4.1 UART Interface
UART_TX, UART_RX, UART_RTS, and UART_CTS form a conventional asynchronous serial data port
with handshaking. The interface is designed to operate correctly when connected to other UART devices
such as the 16550A. The signalling levels are nominal 0 V and 3.3 V, and are inverted with respect to the
signalling on an RS232 cable. The interface is programmable over a variety of bitrates: no, even, or odd
parity; stop bit; and hardware flow control. The default condition on power-up is pre-assigned in the
external flash. UART_RTS and UART_CTS implement two-way hardware flow control. UART_RTS is an
output and is active low. UART_CTS is an input and is active low.
These signals operate according to normal industry convention. UART_RX, UART_TX, UART_CTS,
UART_RTS, UART_RI, UART_DCD, and UART_DSR are all 3.3 V level logic. For example, when RX
and TX idle, they sit at 3.3 V. Conversely for handshaking pins CTS, RTS, RI, DCD, and DSR, a 0 V is
treated as an assertion.
By writing different values to the relevant S register the UART_RI can continuously poll to detect incoming
communication. The UART_RI signal serves to indicate incoming calls.
UART_DSR is an active low input. It should connect to the DTR output of the host. When the module runs
in high speed mode (see definition for S Reg 507), this pin should assert by the host to ensure a
connection maintains. A de-assertion means that the connection should be dropped, or an online
command mode is being requested.
The module communicates with the customer application using the following signals:
Port /TXD of the application sends data to the module’s UART_RX signal line
Port /RXD of the application receives data from the module’s UART_TX signal line
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CONN-GUIDE-BT740_v0.2
Enhanced Class 1 Bluetooth v2.1 Module
User’s Guide
BT740
Application -
UART_TX
/RXD
Host
UART_RX
/TXD
UART_CTS
/RTS
UART_RTS
/CTS
UART_DSR
/DTR
UART_DTR
/DSR
UART_RI
UART_DCD
Note:
/RING
/DCD
The serial module output is at 3.3 V CMOS logic levels. Level conversion must be added to
interface with an RS232 level compliant interface.
Some serial implementations link CTS and RTS to remove the need for handshaking. Laird does not
recommend linking CTS and RTS other than for testing and prototyping. If these pins link and the host
sends data at the point that the BT740 deasserts its RTS signal, then there is a significant risk that
internal receive buffers will overflow, leading to an internal processor crash. This also leads to a drop in
connection and may require a power cycle to reset the module. Laird recommends to follow the correct
CTS/RTS handshaking protocol for proper operation.
4.2 SPI Bus
The module is a slave device that uses terminals SPI_MOSI, SPI_MISO, SPI_CLK, and SPI_CSB. This
interface programs firmware updates at the factory. Laird supplies a PC-based utility to allow a firmware
upgrade over the UART port. Laird highly recommends that customers use this method for updating
firmware.
Note:
The designer should be aware that no security protection is built into the hardware or firmware
associated with this port, so the terminals should not permanently connect in a PC application.
4.3 PCM Interface
PCM_OUT, PCM_IN, PCM_CLK, and PCM_SYNC carry up to three bi-directional channels of voice data,
each at 8 k samples/s. The format of the PCM samples can be 8-bit A-law, 8-bit μ-law, 13-bit linear, or16bit linear. The PCM_CLK and PCM_SYNC terminals can configure as inputs or outputs depending on
whether the module is the master or slave of the PCM interface. Please contact a Laird FAE for further
details.
The module is compatible with the Motorola SSI TM interface and interfaces directly to PCM audio
devices including the following:
4.3.1 Compatible Codec Chips
OKI 7702 single channel A-law and μ-law CODEC
Winbond W681360 13 bit linear CODEC
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CONN-GUIDE-BT740_v0.2
Enhanced Class 1 Bluetooth v2.1 Module
User’s Guide
4.4 General Purpose I/O and ADC
4.4.1 GPIO
Laird provides seven lines of programmable bi-directional input/outputs (I/O) that can be accessed either
via the UART port or Over The Air (OTA) from a second Bluetooth unit. These can be used as data inputs
or to control external equipment. By using these in OTA mode, a BT730 module can be used for control
and data acquisition without the need for any additional host processor. Each of the GPIO[3:9] ports can
independently configure to be either an input or output. A selection of ports can be accessed
synchronously.
The ports power from VCC. The mode of these lines can be configured and the lines are accessed via S
Registers 623 to 629.
4.4.2 ADC
The BT740 provides access to two 8-bit ADCs (Analogue 0 and 1). These provide an input range of 0 mV
to 1,800 mV, which are read using the S registers 701 and 702.
Suitable external scaling and over-voltage protection should be incorporated in your design. The module
provides five samples per second at the UART with a baud rate of 115,200 or above.
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CONN-GUIDE-BT740_v0.2
Enhanced Class 1 Bluetooth v2.1 Module
User’s Guide
5 AT COMMAND SET
5.1 Introduction to AT Commands
This chapter describes the ‘AT’ protocol used to control and configure the BT740-Sx Bluetooth modules
after it is configured to present an ‘AT’ protocol instead of the alternate multipoint packet-based interface.
The Multipoint Protocol is also described in this document.
The protocol is similar to the industry standard Hayes AT protocol used in telephony modems, as both
types of devices are connection oriented. The extended AT command set makes the Laird device
performs the three core actions of a Bluetooth device: establish Bluetooth connections, pair, and inquire.
Many other provided AT commands perform ancillary functions, such as trusted device database
management and S Register maintenance.
Just like telephony modems, the Laird device powers up in an unconnected state and only responds via
the serial interface. In this state the Laird device can respond to Bluetooth Inquiries. Then, just like
controlling a modem, the host issues AT commands which map to various Bluetooth activities. These AT
commands have appropriate counterparts in the alternate multipoint packet based protocol which also
achieve the same goal.
The nature of ‘AT’ protocol allows it to control and manage only one connection at a time; this is in
contrast to the multipoint packet protocol which can simultaneously control many connections. The main
advantage ‘AT’ protocol offers is simplicity.
The module has a serial interface through which the ‘AT’ protocol channels, which can be configured for
baud rates from 1200 up to 921600 and has an RF communications end point. The default baud rate for
AT command mode modules is 9600 bps.
The RF communications endpoint has a concept of connected and unconnected modes and the ‘AT’
protocol at the serial interface has a concept of command and data modes. This leads to the matrix of
states shown below.
Command Mode
Data Mode
RF Unconnected
Allowed
Illegal
RF Connected
Allowed
Allowed
The combination ‘Data + RF Unconnected Mode’ does not make sense and is ignored.
Navigation between these states uses the AT command/responses, described in detail in subsequent
sections.
There are many references to the term ‘S Register’ in the rest of this document. These are an array of
integer values stored in non-volatile memory which are used to configure the module so that it behaves in
a certain way after powering. These ‘S Registers’ have two attributes; a value and an ID. The ‘ID’ is a
positive integer number used in appropriate commands to read/write the values.
5.2 AT Protocol Mode
5.2.1 AT Protocol Assumptions
The CSR (Cambridge Silicon Radio) Bluetooth chipset in Laird devices has limited memory resources.
Therefore it is NOT proposed that there be full implementation of the AT protocol as seen in modems.
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CONN-GUIDE-BT740_v0.2
Enhanced Class 1 Bluetooth v2.1 Module
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The claim made for this device is that it has a protocol similar to an AT modem. In fact, the protocol is
similar enough so that existing source code written for modems can be used with very little modification
with a Laird device.
Therefore the following assumptions are made:
All commands terminate by the carriage return character 0x0D, represented by the string in
subsequent sections. It cannot be changed at runtime.
All responses from the Laird device have carriage return and linefeed characters preceding and
appending the response. These dual character sequences have the values 0x0D and 0x0A
respectively and are represented by the string .
All Bluetooth addresses are represented by a fixed 12 digit case insensitive hexadecimal string.
All Bluetooth Device Class codes are represented by a fixed 6 digit case insensitive hexadecimal
string.
Most new Bluetooth specific commands are identified by the string +BTx, where x is generally a
mnemonic of the intended functionality.
5.2.2 Protocol Activation
Depending on the variant of the module, the AT protocol needs to activate so that on power up it presents
this protocol interface instead of the alternate multipoint protocol.
The method that is always available and works is activation via S Register 255 in multipoint mode (and
mapped to 9255 in AT mode), where setting a value of 1 selects multipoint packet protocol and a value of
2 selects AT protocol.
Note:
Changes to this S register store in non-volatile memory at time of change and does not require
the AT&W command (or the equivalent in multipoint mode CMD_STORE_REG) to commit to
non-volatile memory.
Optionally, some firmware variants allow a value of 0 in this S Register and in this case on power up the
protocol selection depends on the state of one of the GPIO pins (user settable) so that one state forces
AT and the other forces multipoint.
5.3 AT Commands and Responses
This section describes all available AT commands. Many commands require mandatory parameters and
some take optional parameters. These parameters are integer values, strings, Bluetooth addresses or
device classes. The following convention is used when describing the various AT commands, and the
response to a command is also stated.
A 12 character Bluetooth address consisting of ASCII characters ‘0’ to ‘9’, ‘A’ to ‘F’
and ‘a’ to ‘f’.
A 6 character Bluetooth device class consisting of ASCII characters ‘0’ to ‘9’, ‘A’ to
‘F’ and ‘a’ to ‘f’.
A positive integer value.
An integer value which could be positive or negative, which can be entered as a
decimal value or in hexadecimal if preceded by the ‘$’ character.
E.g. the value 1234 can also be entered as $4D2
A string delimited by double quotes. E.g. "Hello World". The " character MUST be
supplied as delimiters.
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CONN-GUIDE-BT740_v0.2
Enhanced Class 1 Bluetooth v2.1 Module
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A 4 character UUID number consisting of ASCII characters ‘0’ to ‘9’, ‘A’ to ‘F’ and
‘a’ to ‘f’.
5.3.1 Enter Local Command Mode
Command:
^^^
Response:
OK
Description:
When in data + connected mode, the host can force the device into a command +
connected mode so that AT Commands can issue to the device while a connection
establishes. The S2 register specifies the character in this escape sequence, so it can
change. The escape sequence guard time sets at compile time to 100 milliseconds.
Please refer to the Dropping Connections section for more related information.
In modems this escape sequence is typically “{delay}+{delay}+{delay}+{delay}”, and
configures by default to avoid confusion when the module is providing access to a
modem.
5.3.2 Command Mode Status Check
Command:
AT
Response:
OK
Description:
OK
5.3.3
Accept Incoming Connection (Answer Call)
Command:
ATA
Response:
CONNECT 123456789012,,<
Where is the profile with the established connection.
Description:
Accept an incoming connection, which is indicated by the unsolicited string
RING 123456789012, where 123456789012 is the Bluetooth address of
the connecting device.
5.3.4 Make Outgoing Connection
Command:
ATD,
Response:
CONNECT 123456789012,,>
Or
NO CARRIER
Description:
Make a connection to device with Bluetooth address and profile .
The is an optional parameter which specifies the UUID of the profile server to
attach to, and if not supplied then uses the default UUID for SPP (1101).
The UUIDs in the following table are allowed:
Profile Name
UUID
Serial Port
1101
HID
1124
HDP
Use appropriate canned HDP commands
instead
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5.3.5 Enable/Disable Echo
Command:
ATEn
Response:
OK
Or
ERROR nn
Description:
This command enables or disables the echo of characters to the host. The default echo
condition sets via S Register 506. This command does not affect the S Register 506.
Disable echo.
Enable echo.
All other values of n generate an error.
5.3.6 Drop Connection
Command:
ATH
Response:
NO CARRIER
Or
OK
Description:
Drop an existing connection or reject an incoming connection indicated by the
unsolicited RING message. If a connection does not exist then the response is OK.
5.3.7 Information
Command:
ATIn
Response:
For recognized values of n.
As AppropriateOK
All other values of n generate
Laird Technologies Inc (c)2010 OK
Description:
This returns the information in the following table about the Laird device. The list is not
exhaustive as there are some values of ‘n’ which generate information for use by Laird
Support.
Table 5-1: Laird device information
Index
Description
The product name/variant.
The underlying CCL Stack version information.
The Laird firmware revision
Format A.B.C.F.G
(See 333 for further details)
333
The full Laird firmware revision
Format A.B.C.D.E.F.G, where
A = Hardware Platform
B = Major Stack Version Number (Changes when CCL stack changes :
see ATi1)
C = Major App Version Number (Changes when number of profiles
change)
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CONN-GUIDE-BT740_v0.2
Enhanced Class 1 Bluetooth v2.1 Module
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Index
Description
D = Developer ID
E = Branch ID
F = Build Number (divisible by 10 for production releases and Odd for
Engineering)
G = Twig Number (will normally be 0, but minor releases on subbranches is non-zero)
A 12 digit hexadecimal number corresponding to the Bluetooth address
of the Laird device.
The maximum size of trusted device database.
0 if not in a connect state and 1 if in a connect state.
11
The reason why a “NO CARRIER” results in the most recent attempt at
making an outgoing connection. Where the response values are as
follows:
3 = Normal disconnection
13
Current Sniff parameters in two lines as follows
A,B,C,D
A,B,C,D
Where first line is in units of milliseconds and the second in baseband
slots.
A = Attempt (see S Reg 73, 561 in AT Mode)
B = Timeout (see S Reg 74, 562 in AT Mode))
C = Minimum Interval (see S Reg 75, 563 in AT Mode)
D = Maximum Interval (see S reg 76, 564 in AT Mode)
21
Current discoverable mode:
0 = Not Discoverable
1 = Generic Discoverable mode
2 = Limited Discoverable mode
22
Current connectable mode:
0 = Not Connectable
1 = Connectable
23
Same as (9) above.
0 if not in a connect state and 1 if in a connect state.
42
Current state of the module
14 = Not discoverable and not connectable and not in connection
18 = Connected mode
174 = Connectable and Discoverable
173 = Connectable only
172 = Discoverable only
56
The number of devices in the trusted device database in format a,b
where ‘a’ is the number of devices in the ‘rolling’ database and ‘b’ in the
‘persistant’ database.
100
Returns the hardware ID (100 for BTM4xx platform)
201
UART receive buffer and hardware handshaking information in the
format:
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CONN-GUIDE-BT740_v0.2
Enhanced Class 1 Bluetooth v2.1 Module
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Index
Description
A,B,C
Where
A = UART receive buffer size
B = Threshold at which the RTS output line deasserts
C = Threhsold at which the RTS output line re-asserts again.
202
The number of times the UART_DSR input line has been detected to
toggle since the module was powered or reset via appropriate
commands in AT and MP mode.
224-239
Memory Diagnostics information in the format “A,B” where A is the size
of pmalloc block and B is the number that are free. Low ‘B’ values imply
trhe module is operating at the limits of it’s heap resource.
5.3.8 Enter Data Mode When Connected and in Command Mode
Command:
ATO
Response:
CONNECT
Or
ERROR nn
Description:
Return to data mode. Assume that the module is in data mode after it receives an OK.
Responds with an error if there is no Bluetooth connection.
5.3.9 Set S Register
Command:
ATSn=m
Response:
OK
Or
ERROR nn
Description:
As with modems, the Laird Bluetooth module employs a concept of registers used to
store parameters, such as escape sequence character, inquiry delay time, etc.
The value part ‘m’ can enter as decimal or hexadecimal. A hexadecimal value is
specified via a ‘$’ leading character. For example, $1234 is a hexadecimal number.
When S register values change, the changes are not normally stored in non-volatile
memory UNTIL the AT&W command is used (unless specifically stated otherwise).
Note that AT&W does not affect some S registers; for example 520 to 525, or 9240 to
9255, as they are updated in non-volatile memory when the command processes.
5.3.10 Read S Register Value in Decimal or Hex
Command:
ATSn?<$>
Response:
For recognised values of n:
As AppropriateOK
For unrecognised values of n:
ERROR nn
Description:
This returns the current value of register n. If the optional $
character supplies after the ?, then the returned value is
hexadecimal with a leading $. For example, the value 1000 returns
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CONN-GUIDE-BT740_v0.2
Enhanced Class 1 Bluetooth v2.1 Module
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as $3E8
5.3.11 Read S Register’s Valid Range
Command:
ATSn=?
Response:
For recognised values of n:
nnnn..mmmmOK
For unrecognised values of n:
ERROR nn
Description:
This returns the valid range of values for register n.
5.3.12 Send Data to Peer When In Command Mode
Command:
ATX
Response:
OK
Or if a connection does not exist
ERROR 56
Description:
This command sends data to the remote device when in local command and
connected mode.
If a non-printable ASCII character needs sent, then insert the escape sequence \hh
where hh are two hexadecimal digits. The three character sequence \hh converts
into a single byte before transmission to the peer.
Note: For HID connections, the entire is deemed to be a single HID report.
5.3.13 Factory Default (Full)
Command:
AT&F*
Response:
OK
Or
ERROR nn
Description:
This command erases all user parameters in non-volatile memory.
The new settings become active after a reset.
5.3.14 Factory Default (Preserve Uart Settings)
Command:
AT&F+
Response:
OK
Or
ERROR nn
Description:
This command erases all user parameters in non-volatile memory except S Registers
520 to 525, and 9240 to 9255. This means that the trusted device database clears, but
‘AT’ protocol moderetains and UART config (baudrate, stopbits etc) is preserved.
The new protocol and settings become active after a reset.
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5.3.15 Factory Default (Preserve Protocol Setting)
Command:
AT&F*AT*
Response:
OK
Or
ERROR nn
Description:
This command erases all user parameters in non-volatile memory except S Register
9255. This means that the trusted device database clears, but ‘AT’ protocol mode
retains and UART parameters reset to factory default settings.
The new protocol and settings become active after a reset.
5.3.16 Factory default (Full, then change into MP mode)
Command:
AT&F*MP*
Response:
OK
Or
ERROR nn
Description:
This command erases all user parameters in non-volatile memory including S Register
9255 and S Reg 9255 is set to 1 for MP mode. This means that the trusted device
database clears, and protocol sets to MP mode and all UART parameters are reset to
factory default settings.
The new protocol and settings become active after a reset.
5.3.17 Write S Registers To Non-Volatile Memory
Command:
AT&W
Response:
OK
Or
ERROR nn
Description:
Writes current S Register values to non-volatile memory so that they retain over a
power cycle.
5.3.18 Write To Blob(0)
Command:
AT+BTB=
Response:
OK
Or
ERROR nn
Description:
This command clears BLOB(0) first and then appended to that BLOB after the
string de-escapes. This allows binary data to load into the BLOB buffer for
subsequent processing using the AT+BTBnnnn command syntax.
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Enhanced Class 1 Bluetooth v2.1 Module
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5.3.19 Append To Blob(0)
Command:
AT+BTB+
Response:
OK
Or
ERROR nn
Description:
This command appends BLOB(0) after the string de-escapes. This allows
binary data to load into the BLOB buffer for subsequent processing using the
AT+BTBnnnn command syntax.
5.3.20 Action And Process Data In Blob(0)
Command:
AT+BTBnnnn
Response:
OK
Or
ERROR nn
Description:
This command processes BLOB(0) as per the action specified by ‘nnnn’. The actions
are described briefly as per the table below (more details in the MP protocol section):
Index
Action
Clear Blob(0)
Get byte count in Blob(0)
Destructively read Blob(0). Data sends so that non-printable data
bytes are escaped with \hh.
Save Blob(0) as Hid Descriptor(0) in non-volatile memory
Load Blob(0) as Hid Descriptor(0) from non-volatile memory
Save Blob(0) as Hid Service Name in non-volatile memory
Load Blob(0) as Hid Service name from non-volatile memory
Commit Blob(0) as Enhanced Inquiry Data
Save Blob(0) as Enhanced Inquiry Data in non-volatile memory, to be
used automatically after subsequent resets
Load Blob(0) from the Enhanced Inquiry Data from non-volatile
memory.
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CONN-GUIDE-BT740_v0.2
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5.3.21 Remove Trusted Device
Command:
AT+BTD
Response:
OK
Or
ERROR nn
Description:
This command removes the specified device from the list of trusted devices in the nonvolatile database. If the device is not in the database then the response is still an OK.
Error response is for when the address is not a 12 character hex string.
5.3.22 Remove All Trusted Devices
Command:
AT+BTD*
Response:
OK
Or
ERROR nn
Description:
This command removes all devices from the list of trusted devices in the non-volatile
database. The device does not ask for confirmation.
WARNING: If you make a connection, the link key caches in the underlying stack. So
if you subsequently delete the key using AT+BTD* and immediately
request an authenticated connection to the same device, then the
connection may be established. To ensure this does not happen, send
ATZ after the AT+BTD*.
5.3.23 Get the Remote Friendly Name
Command:
AT+BTF
Response:
Friendly Name
OK
Or
ERROR nn
Description:
This command gets the remote friendly name of the specific address.
If the friendly name has non printable characters (including the character “) then those
characters escape into a 3 character ‘\hh’ sequence.
5.3.24 Enable Connectable Mode
Command:
AT+BTG
Response:
OK
Or
ERROR nn
Description:
Enable page scanning only and wait for a connection from any device. Inquiry scans
are disabled.
The page scan window and interval timing derives from S Reg 9009 and 9010.
Use ATi21 and ATi22 to determine the discoverable and connectable modes at any
time.
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CONN-GUIDE-BT740_v0.2
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5.3.25 Inquire
Command:
AT+BTI
Response:
12346789012
12345678914
OK
Description:
This makes the device perform an inquiry for ‘duration’ milliseconds and ‘max’ number
of unique responses, where S register 517 specifies ‘duration’ and S register 518
specifies ‘max’. Only the Bluetooth address of responding devices is listed.
5.3.26 Inquire And Display Devclass Too
Command:
AT+BTIV
Response:
12346789012,123456
12345678914,123456
OK
Description:
As per AT+BTI but the response includes the device class code for all inquiry
responses.
5.3.27 Inquire and Get Friendly Names Too
Command:
AT+BTIN
Response:
12346789012,123456,"Laird BT Module"
12345678914,123456, “Nokia N70"
OK
Description:
As per AT+BTI but the response includes the device class code and friendly name for
all inquiry responses. The friendly name strings are in UTF-8 format as per the
Bluetooth specification.
5.3.28 Inquire with Enhanced Inq Resp
Command:
AT+BTIE
Response:
12346789012,123456,””,-45,"\0A\08Laird FEF"
12345678914,123456,“",-75,””
OK
Description:
As per AT+BTI but the response includes the device class code, RSSI, and the
enhanced inquiry information. The friendly name is not acquired, as it is a timeexpensive procedure and therefore an empty string sends as a placeholder.
5.3.29 Set Pincode or Passcode
Command:
AT+BTK=
Response:
OK
Or
ERROR nn
Description:
This command provides a passkey when PIN? 12345678 or PASSKEY? 12345678
indications receive asynchronously.
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Enhanced Class 1 Bluetooth v2.1 Module
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The string length must be in the range 1 to 16, for PIN? otherwise an error returns.
The string length must be exactly 6 characters, for PASSKEY? otherwise an error
returns and each character MUST be a decimal digit in the range 0 to 9.
If there is no ongoing pairing in progress, then the stores in non-volatile
memory and may be used in subsequent legacy pairing attempts. To delete the
pincode stored in non-volatile memory, submit the command with an empty string. A
stored value is not used for a PASSKEY? Event.
5.3.30 Reject Yes/No Simple Secure Pairing
Command:
AT+BTKN
Response:
OK
Or
ERROR nn
Description:
When the module configures for ‘Display with Yes/No’ security via S Register 9006,
this command conveys a ‘NO’ for the simple pairing procedure. This command sends
as a result of receiving a “PASSKEY? 2 ” asynchronous response.
5.3.31 Accept Yes/No Simple Secure Pairing
Command:
AT+BTKY
Response:
OK
Or
ERROR nn
Description:
When the module configures for ‘Display with Yes/No’ security via S Register 9006
then this command conveys a ‘YES’ for the simple pairing procedure. This command
sends as a result of receiving a “PASSKEY? 2 ” asynchronous response.
5.3.32 Set Friendly Name in Non-Vol Memory
Command:
AT+BTN=
Response:
OK
Or
ERROR nn
Description:
This sets the default friendly name of this device as seen by other devices. It stores in
non-volatile memory. Use AT+BTN? To read it back. An empty string (“”) deletes the
string from non-volatile memory which forces the use of the default friendly name.
5.3.33 Read Friendly Name From Non-Vol Memory
Command:
AT+BTN?
Response:
My FriendlyName
OK
Or
ERROR nn
Description:
Read the friendly name from non-volatile memory.
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Enhanced Class 1 Bluetooth v2.1 Module
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5.3.34 Enable Connectable+Discoverable Mode
Command:
AT+BTP
Response:
OK
Or
ERROR nn
Description:
Enable page and inquiry scanning and wait for a connection from any device.
The page scan window and interval timing derives from S Reg 9009 and 9010.
The inquiry scan window and interval timing derives from S Reg 9007 and
9008.
5.3.35 Enable Discoverable Mode Only
Command:
AT+BTQ
Response:
OK
Or
ERROR nn
Description:
Set discoverable mode only by enabling inquiry scanning.
The inquiry scan window and interval timing derives from S Reg 9007 and 9008.
Use ATi21 and ATi22 to determine the discoverable and connectable modes at any
time.
5.3.36 List Trusted Device
Command:
AT+BTT?
Response:
12346789012
12345678913
12345678914
OK
Or
ERROR nn
Description:
This command lists the contents of both the ‘rolling’ and the ‘persist’ trusted device
database. The link key does NOT display so the response is as shown above. If the
list is empty, only the OK response sends; otherwise an OK terminates the list. Use
the command ATI6 to read the maximum size of the trusted device database.
Note:
All new successful pairings automatically store in the ‘rolling’ database. If
the database is full, then the oldest is deleted to make room for the new
one. To ensure a link key is never deleted, transfer it to the ‘persist’
database using the command AT+BTT described in detail later.
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CONN-GUIDE-BT740_v0.2
Enhanced Class 1 Bluetooth v2.1 Module
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5.3.37 List Trusted Device
Command:
AT+BTTn?
Response:
12346789012
12345678913
12345678914
OK
Or
ERROR nn
Description:
This command lists the contents of either the ‘rolling’ or the ‘persist’ trusted device
database, where n=0 for the rolling database and 1 for the persist database. The link
key does NOT display so the response is as shown below. If the list is empty then just
the OK response sends; otherwise an OK terminates the list. Use the command ATI6
to read the maximum size of the trusted device database.
5.3.38 Transfer Device To ‘Persist’ List
Command:
AT+BTT
Response:
OK
Or
ERROR nn
Description:
When a successful pairing occurs, the new link key automatically stores in the ‘rolling’
database where if the database is full, the oldest device is deleted. This poses a risk of
a trusted device automatically deleting, especially when the module is in ‘just works’
simple pairing mode and so pairings can occur without the host being involved and so
there is a definite risk of link key deletion.
This command transfers a device specified via the address supplied to the ‘persist’
database so that a trusted device is never deleted automatically.
5.3.39 Initiate a Pairing
Command:
AT+BTW
Response:
OK
Or
ERROR nn
Description:
This initiates pairing with a device whose Bluetooth address is . An OK
response sends immediately and when the PIN or PASSCODE is required.
Asynchronous indications send to the host in the form PIN? or PASSKEY?
or PAIR ? where the address confirms the device with which the
pairing is to be performed. To supply a PIN or passcode, use the AT+BTK command.
To respond with a YES or NO, use the command AT+BTKY or AT+BTKN respectively.
For a successful pairing, the link key automatically stores in the ‘rolling’ database which
can be queried using the AT+BTT0? Command.
Note: The “OK” response sends immediately on receipt of the AT+BTW command. On
pairing completion, an unsolicited message sends to the host in the form PAIR n
, where n is 0 for a successful pairing.
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5.3.40 Disable Connectable And Discoverable Mode
Command:
AT+BTX
Response:
OK
Or
ERROR nn
Description:
Disable page/inquiry scanning. This means it does not accept incoming connections or
inquiry requests. More specifically it negates the effect of AT+BTQ, AT+BTG and
AT+BTP commands.
Use ATi21 and ATi22 to determine the discoverable and connectable modes at any
time.
5.3.41 HDP: Associate The Agent With Manager
Command:
AT+HAAhhhh
Response:
OK
Or
ERROR nn
Description:
This is a Health Device Profile (HDP Agent related command. Refer to Application
Examples for details). Please note ERROR 59 implies that the profile has not been
activated which means bit 2 in S Reg 9003 is not set AND S Reg 9070 is not 0.
‘hhhh’ is obtained as a response to the AT+HAB command.
5.3.42 HDP: Bind Manager to Agent
Command:
AT+HAB,iiii
Response:
hhhhOK
Or
ERROR nn
Description:
This is a Health Device Profile (HDP Agent related command. Refer to Application
Examples for details). Please note ERROR 59 implies that the profile has not been
activated which means bit 2 in S Reg 9003 is not set AND S Reg 9070 is not 0.
‘iiii’ is the nominal code for the data specialization.
5.3.43 HDP: Disassociate The Agent From Manager
Command:
AT+HADhhhh
Response:
OK
Or
ERROR nn
Description:
This is a Health Device Profile (HDP Agent related command. Refer to Application
Examples for details). Please note ERROR 59 implies that the profile has not been
activated which means bit 2 in S Reg 9003 is not set AND S Reg 9070 is not 0.
Americas: +1-800-492-2320 Option 2
Europe: +44-1628-858-940
Hong Kong: +852-2923-0610
www.lairdtech.com/wireless
29
CONN-GUIDE-BT740_v0.2
Enhanced Class 1 Bluetooth v2.1 Module
User’s Guide
5.3.44 HDP: Endpoint Definition In SDP Record
Command:
AT+HAE,iiii,”endpointname”
Response:
OK
Or
ERROR nn
Description:
This is a Health Device Profile (HDP Agent related command. Refer to Application
Examples for details). Please note ERROR 59 implies that the profile has not been
activated which means bit 2 in S Reg 9003 is not set AND S Reg 9070 is not 0.
It inserts details in the SDP record.
5.3.45 HDP: Read Attribute Value In Agent
Command:
AT+HAGhhhh,aaaa,ssss
Response:
OK
Or
ERROR nn
Description:
This is a Health Device Profile (HDP Agent related command. Refer to Application
Examples for details). Please note ERROR 59 implies that the profile has not been
activated which means bit 2 in S Reg 9003 is not set AND S Reg 9070 is not 0.
5.3.46 HDP: Activate SDP Record For Agent
Command:
AT+HAL
Response:
OK
Or
ERROR nn
Description:
This is a Health Device Profile (HDP Agent related command. Refer to Application
Examples for details). Please note ERROR 59 implies that the profile has not been
activated which means bit 2 in S Reg 9003 is not set AND S Reg 9070 is not 0.
5.3.47 HDP: Trigger Agent Scan Report
Command:
AT+HARhhhh,pppp[,aaaa[,aaaa[…]]]
Response:
OK
Or
ERROR nn
Description:
This is a Health Device Profile (HDP Agent related command. Refer to Application
Examples for details). Please note ERROR 59 implies that the profile has not been
activated which means bit 2 in S Reg 9003 is not set AND S Reg 9070 is not 0.
Americas: +1-800-492-2320 Option 2
Europe: +44-1628-858-940
Hong Kong: +852-2923-0610
www.lairdtech.com/wireless
30
CONN-GUIDE-BT740_v0.2
Enhanced Class 1 Bluetooth v2.1 Module
User’s Guide
5.3.48 HDP: Write Attribute Value To Agent
Command:
AT+HAShhhh,aaaa,ssss,ddddd
Response:
OK
Or
ERROR nn
Description:
This is a Health Device Profile (HDP Agent related command. Refer to Application
Examples for details). Please note ERROR 59 implies that the profile has not been
activated which means bit 2 in S Reg 9003 is not set AND S Reg 9070 is not 0.
5.3.49 HDP: Endpoint Definition in SDP Record (Manager)
Command:
AT+HME,iiii,”endpointname”
Response:
OK
Or
ERROR nn
Description:
This is a Health Device Profile (HDP Manager related command. Refer to Application
Examples for details. Please note ERROR 59 implies that the profile has not been
activated which means bit 2 in S Reg 9003 is not set AND S Reg 9070 is not 1.
5.3.50 HDP: Endpoint Definition in SDP Record (Manager)
Command:
AT+HME,iiii,”endpointname”
Response:
OK
Or
ERROR nn
Description:
This is a Health Device Profile (HDP Manager related command. Refer to Application
Examples for details). Please note ERROR 59 implies that the profile has not been
activated which means bit 2 in S Reg 9003 is not set AND S Reg 9070 is not 1.
5.3.51 HDP: Activate SDP Record For Agent (Manager)
Command:
AT+HML
Response:
OK