Ingenu ULPD100 The ULP dNode is a wireless network module User Manual dNode Integration Specification
On-Ramp Wireless The ULP dNode is a wireless network module dNode Integration Specification
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dNode Integration
Specification
On-Ramp Wireless Incorporated
10920 Via Frontera, Suite 200
San Diego, CA 92127
U.S.A.
Copyright © 2012 On-Ramp Wireless Incorporated.
All Rights Reserved.
The information disclosed in this document is proprietary to On-Ramp Wireless Inc., and is not to be used
or disclosed to unauthorized persons without the written consent of On-Ramp Wireless. The recipient of
this document shall respect the security of this document and maintain the confidentiality of the
information it contains. The master copy of this document is stored in electronic format, therefore any
hard or soft copy used for distribution purposes must be considered as uncontrolled. Reference should
be made to On-Ramp Wireless to obtain the latest version. By accepting this material the recipient agrees
that this material and the information contained therein is to be held in confidence and in trust and will not
be used, copied, reproduced in whole or in part, nor its contents revealed in any manner to others without
the express written permission of On-Ramp Wireless Incorporated.
On-Ramp Wireless Incorporated reserves the right to make changes to the product(s) or information
contained herein without notice. No liability is assumed for any damages arising directly or indirectly by
their use or application. The information provided in this document is provided on an “as is” basis.
This document contains On-Ramp Wireless proprietary information and must be shredded when
discarded.
This documentation and the software described in it are copyrighted with all rights reserved. This
documentation and the software may not be copied, except as otherwise provided in your software
license or as expressly permitted in writing by On-Ramp Wireless, Incorporated.
Any sample code herein is provided for your convenience and has not been tested or designed to work
on any particular system configuration. It is provided “AS IS” and your use of this sample code, whether
as provided or with any modification, is at your own risk. On-Ramp Wireless undertakes no liability or
responsibility with respect to the sample code, and disclaims all warranties, express and implied,
including without limitation warranties on merchantability, fitness for a specified purpose, and
infringement. On-Ramp Wireless reserves all rights in the sample code, and permits use of this sample
code only for educational and reference purposes.
This technology and technical data may be subject to U.S. and international export, re-export or transfer
(“export”) laws. Diversion contrary to U.S. and international law is strictly prohibited.
Ultra-Link Processing™ is a trademark of On-Ramp Wireless.
Other product and brand names may be trademarks or registered trademarks of their respective owners.
dNode Integration Specification
014-0038-00 Rev. B
July 11, 2012
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Contents
1 Overview ................................................................................................................ 1
1.1 ULP Wireless Network ............................................................................................................... 1
1.2 dNode ......................................................................................................................................... 2
1.3 Referenced Documents ............................................................................................................. 3
2 DC and AC Characteristics .................................................................................. 4
2.1 Absolute Maximum Ratings ....................................................................................................... 4
2.2 Recommended Operating Conditions ........................................................................................ 4
2.3 Effects of Temperature and Voltage .......................................................................................... 6
3 Electrical Interface ................................................................................................ 9
3.1 Signal Connectors ...................................................................................................................... 9
3.2 Pin Descriptions ......................................................................................................................... 9
3.3 Signal Descriptions .................................................................................................................. 11
3.3.1 VBATT ............................................................................................................................ 11
3.3.2 RESET_N ....................................................................................................................... 11
3.3.3 MRQ ............................................................................................................................... 11
3.3.4 SRDY .............................................................................................................................. 11
3.3.5 SRQ ................................................................................................................................ 11
3.3.6 USTATUS ....................................................................................................................... 11
3.3.7 SPI System ..................................................................................................................... 12
3.3.8 RF ................................................................................................................................... 12
3.4 Environmental .......................................................................................................................... 12
3.4.1 ESD ................................................................................................................................ 12
3.4.2 Harsh Environments ....................................................................................................... 12
4 SPI Interface and Sequences ............................................................................. 13
4.1 SPI System Interface Overview ............................................................................................... 13
4.2 SPI Mode and Timing............................................................................................................... 14
4.3 Startup (Power On) Sequence ................................................................................................. 14
4.4 Wake Sequence ....................................................................................................................... 15
4.4.1 Wake Sequence (Synchronous) ..................................................................................... 16
4.4.2 Wake Sequence (Asynchronous) ................................................................................... 17
4.5 Host-Driven Reset Sequence .................................................................................................. 18
4.6 Host MRQ Release/dNode Allowed to Sleep Sequence ......................................................... 19
5 Power States ....................................................................................................... 20
5.1 Operating States ...................................................................................................................... 20
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5.1.1 Power Off State .............................................................................................................. 20
5.1.2 Deep Sleep State ........................................................................................................... 21
5.1.3 Oscillator Calibration State ............................................................................................. 21
5.1.4 Idle State ........................................................................................................................ 22
5.1.5 RX State ......................................................................................................................... 22
5.1.6 TX State .......................................................................................................................... 22
5.2 System ..................................................................................................................................... 22
6 Messaging Protocol ............................................................................................ 24
6.1 Arbitration ................................................................................................................................. 24
6.2 Message Protocol .................................................................................................................... 24
6.3 Host Interface SPI Bus State Machine..................................................................................... 27
6.4 SPI Bus Timing Example ......................................................................................................... 28
6.5 Host Message SPI Example .................................................................................................... 29
6.6 Host Message “Connect” SPI Example ................................................................................... 31
7 dNode Configuration .......................................................................................... 34
8 Antenna Diversity ............................................................................................... 35
8.1 Antenna Design Requirements ................................................................................................ 35
8.2 Diversity Considerations .......................................................................................................... 35
9 Regulatory Considerations ................................................................................ 36
9.1 Block Diagram .......................................................................................................................... 36
9.2 Certifications ............................................................................................................................ 37
9.3 FCC Warnings .......................................................................................................................... 37
9.4 IC Warnings ............................................................................................................................. 38
9.5 ETSI Warnings ......................................................................................................................... 39
9.6 Usage ....................................................................................................................................... 39
9.6.1 Note to Integrators .......................................................................................................... 39
9.6.2 RF Exposure Statement ................................................................................................. 39
9.7 Antennas .................................................................................................................................. 39
10 Design Considerations for the Host ................................................................ 41
10.1 Host Mounting Method: Socketed .......................................................................................... 41
10.1.1 Host PCB Land Pattern ................................................................................................ 41
10.1.2 Pad Stack for Mill-Max Series 834 ............................................................................... 42
10.2 Host Mounting Method: Direct Solder .................................................................................... 43
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11 Errata ................................................................................................................. 44
Appendix A Abbreviations and Terms ................................................................. 45
Appendix B dNode Mechanical Drawing ............................................................. 47
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Figures
Figure 1. On-Ramp Wireless ULP Network ..................................................................................... 1
Figure 2. dNode (Top and Bottom Views) ........................................................................................ 2
Figure 3. Typical Application Diagram ............................................................................................. 2
Figure 4. dNode Deep Sleep Power Consumption (mW Power vs Voltage Input) .......................... 7
Figure 5. RX State Power Consumption (mW Power vs VBATT Input) .......................................... 7
Figure 6. TX Power Consumption at 20.9 dBm (mW Power vs VBATT Input) ................................ 8
Figure 7. Bottom of the dNode Showing the J701 and J703 Pins on the Signal
Connectors ................................................................................................................................ 9
Figure 8. SPI Timing, CPOL = 0, CPHA = 0 .................................................................................. 14
Figure 9. dNode Host-driven Initial Power-up Sequence ............................................................... 15
Figure 10. Host-Initiated dNode Wake Sequence – SRDY Low (Synchronous) ........................... 16
Figure 11. Host-Initiated dNode Wake Sequence – SRDY High (Asynchronous)......................... 17
Figure 12. Host-Driven Reset Sequence ....................................................................................... 18
Figure 13. Host MRQ Release/dNode Allowed to Sleep Sequence .............................................. 19
Figure 14. dNode Oscillator Calibration: Current (Amps) vs Time (Seconds) ............................... 21
Figure 15. Representative Current Consumption During Deep Sleep, Idle, RX, and TX;
x16 Spreading Factor (Amps vs Seconds) .............................................................................. 23
Figure 16. SPI Master and Slave Message Sequences ................................................................ 26
Figure 17. Host Interface SPI Bus State Machine ......................................................................... 27
Figure 18. SPI Timing Example ..................................................................................................... 28
Figure 19. Host Message on SPI – MMsg Pair .............................................................................. 29
Figure 20. Host Message on SPI – MHdr Pair ............................................................................... 30
Figure 21. dNode Block Diagram ................................................................................................... 36
Figure 22. Host PCB Land Pattern – Mill-Max Socket ................................................................... 41
Figure 23. Pad Stack for Mill-Max Series 834 ............................................................................... 42
Figure 24. Host PCB Land Pattern – Direct Solder ....................................................................... 43
Figure 25. dNode Mechanical Dimensions .................................................................................... 47
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Tables
Table 1. Absolute Maximum Ratings ............................................................................................... 4
Table 2. Operating Conditions ......................................................................................................... 4
Table 3. Operating Characteristics .................................................................................................. 4
Table 4. dNode J701 Pin Descriptions ............................................................................................. 9
Table 5. dNode J703 Pin Descriptions ........................................................................................... 10
Table 6. dNode Antenna Pin Descriptions ..................................................................................... 10
Table 7. ESD Information ............................................................................................................... 12
Table 8. dNode Certifications ......................................................................................................... 37
Table 9. On-Ramp Wireless EMC Certified Antenna ..................................................................... 39
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Revision History
Revision Release Date Change Description
A May 24, 2012 Initial release.
B July 11, 2012 Updated the Maximum RF Conducted Power and clarified
antenna configuration and defaults.
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1 Overview
This document provides a brief overview of the Ultra-Link Processing™ (ULP) wireless network
as well as guidelines allowing an integrator to design a Host product that utilizes the dNode and
ensures that the system meets all of its technical objectives and requirements to enable remote
wireless communication.
1.1 ULP Wireless Network
The On-Ramp Wireless ULP network is comprised of dNodes and Access Points (AP) and
operates in the unlicensed 2.4 ISM band at a receive-sensitivity of -142 dBm. The dNode is
designed to easily integrate, through standard interfaces, with sensors enabling robust wireless
communication with one or more Access Points interfaced with a customer’s local or wide area
network.
Figure 1. On-Ramp Wireless ULP Network
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1.2 dNode
The ULP dNode is a third generation, small form factor wireless network module that easily
integrates with various devices and sensors using an industry standard Serial Peripheral
Interface (SPI). Most of the top side of the printed circuit board (PCB) is enclosed with a radio
frequency (RF) shield except for the two RF connectors. The RF connectors are MMCX (Jack)
receptacles. The PCB bottom side consists of two single-row, 0.1 in pitch (2.54mm) headers,
J701 and J703.
Figure 2. dNode (Top and Bottom Views)
The following figure shows how a dNode interfaces with a Host application.
Figure 3. Typical Application Diagram
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1.3 Referenced Documents
The following documents are referenced and provide more detail.
n ULP Node Interface Library (UNIL) (010-0066-00)
Provides information about the library of portable C code provided by On-Ramp Wireless
which can be integrated into a customer’s existing software architecture.
n UNIL API (010-0072-00)
Provides details relating to the UNIL Application Programming Interface.
n ULP Node Host Message Specification (014-0020-00)
Provides details relating to Node Host messages.
n Node FCC/IC/ETSI EMC Compliance Test Procedures (009-0021-00)
Describes and explains the FCC/IC/ETSI EMC compliance tests and how to use On-Ramp
Wireless’s configuration software for these tests.
n NPT User Guide (010-0060-00)
Describes setup, configuration, and use of a collection of utilities called Node Provisioning
Tools (NPT) used for Node provisioning.
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2 DC and AC Characteristics
2.1 Absolute Maximum Ratings
Operating outside of these ranges may damage the unit.
Table 1. Absolute Maximum Ratings
Parameter Min Max Unit
Storage Temperature -40 85 ⁰C
Operating Temperature -40 85 ⁰C
Input Voltage 2.5 5.5 V
2.2 Recommended Operating Conditions
Table 2. Operating Conditions
Parameter Min Max Unit
Input voltage, VBATT 2.5 5.5 V
Ambient Temperature, Ta -40 85 ⁰C
The following characteristics apply across the -40°C to +85°C temperature range unless
otherwise noted.
Table 3. Operating Characteristics
Description Min Typ Max Units
DC Characteristics
Voltage – VBATT 2.5 3.6 5.5 Volt
Off Current – Note 1 0.05 0.1 2.0 µA
Deep Sleep Current - Note 1 10 20 40 µA
Idle Current – Note 1 10 15 25 mA
Receive Current – Note 1 75 85 90 mA
Transmit Current – Note 2 200 245 280 mA
Digital
VOL – Voltage Output, Low (4mA sink) 0 0.1 V
VOH – Voltage Output High (4mA source) 2.4 3.2 V
Environmental
Operating Temperature -40 +85 °C
Storage Temp -40 +85 °C
Humidity – non-condensing 5 95 %
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Description Min Typ Max Units
Ramp Temperature (maximum rate at which operating
temperature should change) 30 °C/Hr.
Receiver
Receiver Sensitivity – Note 3 -130 -133 -135 dBm
Receiver Image Reject 38 45 50 dB
Noise Figure 3.5 5.0 6.7 dB
Input IP3 (high LNA gain mode) -11 dBm
Maximum RF input level for specification compliance -20 dBm
General RF Characteristics
Frequency Range – Note 4 2402 ~2482 MHz
Channel Spacing N/A 1.99 N/A MHz
Transmitter
Maximum RF Conducted Power –Note 5
FCC/IC markets:
ETSI markets:
19.5
8.5
20.4
9.5
20.9
10.0
dBm
dBm
Carrier Rejection -35 -40 -50 dBc
Signal Modulation DSSS-
DBPSK
Signal Bandwidth 1.0 MHz
BT Factor 0.3
Peak to Average Ratio 2.3 dB
Spectral bandwidth at maximum RF power:
-6dB BW
-20dB BW
0.96
1.75
MHz
MHz
ACPR – Note 6 -30 dBc
Harmonics – Note 7 -43 dBm
Transmit Power Level Accuracy – Note 8 ±1.5 dB
Transmitter Spurious Outputs – Note 9
30MHz to 2400MHz:
2482MHz to 8000MHz:
< -43
< -43
dBm
dBm
VSWR Tolerance
Maximum VSWR for spec compliance – Note 10:
Maximum VSWR for stability.
1.5:1
9:1
NOTES:
1. Tested at 3.6V input.
2. Measured at 20.9 dBm TX output (Typ=50Ω), 3.6V, range includes VSWR ≤ 1.5:1 (Po not
compensated).
3. Sensitivity at maximum spreading factor of 13 (8192) with 10% FER.
4. The upper frequency range is market dependent:
a. FCC/IC: CH38; 2475.63 MHz.
b. ETSI: CH40; 2479.61 MHz.
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c. Japan: CH41; 2481.60 MHz.
5. Maximum TX RF power is limited by FCC/IC grant to 20.9 dBm in these markets.
6. Spec and test method comes from FCC 15.247(d); Band Edge Emissions, 2 MHz offset.
7. At any TX power level, VSWR ≤ 3:1. Harmonics fall into FCC restricted bands.
8. Estimated sum of all contributors with VSWR ≤ 1.5:1. Normal link mode.
9. At any TX power level, VSWR ≤ 3:1. Applies to spurious, not ACPR or harmonics. Generally
the largest spurious output outside the 2.40-2.48GHz band is at 2/3LO and 4/3LO.
10. Maximum VSWR for spec compliance applies at 25°C only. Slightly degraded ACPR/mask and
power variation can be expected at temperature extremes.
2.3 Effects of Temperature and Voltage
The dNode is based largely on Complementary Metal–Oxide–Semiconductor (CMOS)
technology. The current drain of CMOS circuitry can vary substantially over Temperature. The RF
circuitry and its performance also vary substantially over Temperature.
The dNode utilizes two main power domains when it is functioning:
1. LDO Regulators that work from 2.5V up to 5.5V.
These are enabled when the POWER_ON signal for the dNode is active. These can act as a
linear load as voltage increases from minimum to maximum – although these circuits do not
normally consume much power.
2. Switching power domains.
When the dNode wakes up to communicate with the Host or for networking events, its
switching regulators are enabled. These buck-boost switching regulators supply the 3.3V
and other logic supplies over the input range of 2.5-5.5V. The power efficiency of these
regulators change dramatically over input voltage, load levels, and temperature. Nominally,
the power efficiency is best at 3-4.0V. The efficiency becomes poor below 3.0V and is
moderately efficient at the higher input levels.
The following graphs show the relative differences across the operating voltages and their effect
on current consumption.
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Figure 4. dNode Deep Sleep Power Consumption (mW Power vs Voltage Input)
Figure 5. RX State Power Consumption (mW Power vs VBATT Input)
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Figure 6. TX Power Consumption at 20.9 dBm (mW Power vs VBATT Input)
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3 Electrical Interface
This chapter describes the electrical interface of the dNode and how the Host processor controls
the dNode.
3.1 Signal Connectors
n The PCB bottom side consists of two single-row 0.1 inch pitch (2.54 mm) headers, J701 and
J703. All user interfaces to the dNode, with the exception of RF, are through these two
connectors.
n The header mating contacts are 0.228 inch (5.8 mm).
n J701, 1x10 SIP headers, 2.54 mm pitch, 5.8 mm long
n J703, 1x10 SIP headers, 2.54 mm pitch, 5.8mm long
J703 Pin 1
J701 Pin 1
Figure 7. Bottom of the dNode Showing the J701 and J703 Pins on the Signal Connectors
3.2 Pin Descriptions
Table 4. dNode J701 Pin Descriptions
J701 Pin # Pin Name Signal
Direction
Relative to
dNode
Signal Type Polarity Comment
1 Not Used Not Used DO NOT
CONNECT
2 Not Used Not Used DO NOT
CONNECT
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J701 Pin # Pin Name Signal
Direction
Relative to
dNode
Signal Type Polarity Comment
3 T_OUT Output CMOS_O Active High Time Sync Pulse
4 RESET Input
CMOS_I Active Low dNode Reset
5 SPI_CS Input CMOS_I Active Low SPI Chip Select
6 SPI_SCLK Input CMOS_I Serial Clock
7 SPI_MOSI Input CMOS_I Active High Master Out
Slave In
8 SPI_MISO Output CMOS_O Active High Master In Slave
Out
9 GND Ground Power
10 GND Ground Power
Table 5. dNode J703 Pin Descriptions
J703 Pin # Pin Name Signal
Direction
Relative to
dNode
Signal Type Polarity Comment
1 VBATT Power Power
2 VBATT Power Power
3 RXD1 Reserved DO NOT
CONNECT
4 TXD1 Reserved DO NOT
CONNECT
5 GND Ground Power
6 SPI_MRQ Input CMOS_I Active High Master Request
7 SPI_SRQ Output CMOS_O Active High Slave Request
8 SPI_SRDY Output CMOS_O Active High Slave Ready
9 GND Ground Power
10 GND Ground Power
Table 6. dNode Antenna Pin Descriptions
Pin Name Signal Direction Relative to dNode Signal Type
Antenna 1 Input/Output – Default* 50 Ohm RF
Antenna 2 Input/Output 50 Ohm RF
* The antennas for the dNode can be configured as a single antenna device or a diversity
antenna device (both antennas). When the dNode configuration is set to single antenna,
Antenna 1 is the default. This antenna configuration is set by the NPT. For further details, see
the NPT User Guide (010-0060-00).
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3.3 Signal Descriptions
3.3.1 VBATT
This is the main power to the dNode. This needs a low impedance source to the Host’s power
source. It is recommended that the Host have provision for up to a 100 µF low ESR capacitor. It
is likely this capacitor is not required if low impedance design rules are followed.
3.3.2 RESET_N
The RESET_N pin serves a dual purpose. In an effort to ensure a pin for pin compatibility to On-
Ramp Wireless’ eNode, the Reset pin serves a dual electrical purpose: Reset and Power On.
n When the RESET_N pin is asserted Low, the Power to the dNode is turned off. The resultant
current is nominally under 1µA. This is a valid and supported state. The eNode did not have
this function, but the microNode does support a Power Off function that is split over two
pins (POWER_ON and RESET_N). During the Reset of the dNode, all other signals to the
dNode are either low or floating, providing no electrical energy to the powered off device.
n When the dNode is released from Reset, it wakes up and its regulators turn on. After the
dNode has been successfully awakened, it asserts its SRDY to indicate that it is ready for
communication.
3.3.3 MRQ
The MRQ (Master Request) is the Host’s normal way of waking the dNode to initiate SPI
communications. Logic “High” forces the dNode awake.
3.3.4 SRDY
SRDY (Slave Ready) is an indication from the dNode that it has fully booted its internal Firmware
image, initialized its Hardware and Interfaces, and is ready for communication (arbitration) with
the Host. Logic “High” indicates the dNode is ready for communications.
3.3.5 SRQ
The SRQ (Slave Request) signal is an indication from the dNode that it wants the Host’s
attention. When SRQ is asserted “High,” the Host must read the Status registers of dNode. If
SRQ is “High,” SRDY will also be “High.”
3.3.6 USTATUS
USTATUS is currently undefined. In software it can be either an Input or Output. Currently it is
configured as an input. The Host should not use this signal.
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3.3.7 SPI System
The SPI system is the generic term used for all SPI signals (MOSI, MISO, CS, SCLK) to be set up for
SPI communications to occur between Host and dNode.
The dNode SPI is the Slave in the Master/Slave communications and is defined in section 4.2: SPI
Mode and Timing.
3.3.8 RF
The dNode supports two MMCX ports. These two ports are required for antenna diversity. Each
port is a nominal 50 Ohms. For best results, ensure that the load termination (antenna) has a
VSWR of 1.5:1 or better (return loss < -14 dB).
3.4 Environmental
3.4.1 ESD
The dNode is designed to be a truly embedded module and can almost be considered an IC. The
dNode is to be placed as a direct-connect to the Host CPU. Therefore, the dNode has inherent
minimal electrostatic discharge (ESD) protection on its I/O.
Table 7. ESD Information
ESD Model Class and Minimum Voltage
HBM Class 1C ( >1000V)
MM Class A (>100V)
The RF port does have some protection in the form of an inductor to ground, thus allowing
some robustness to direct ESD strikes.
If the application is intended for harsh ESD or lightning strike scenarios it is recommended that
the Integrator take extra precautions to guard against accidental resets or ESD damage.
3.4.2 Harsh Environments
The dNode employs two 10-pin SIP connectors for mount onto the host. A robust socket, such as
a machined pin, can be used for the dNode. This initially adds cost but eases potential
replacement costs for large scale provisioning. For truly robust applications, it is recommended
that the dNode be soldered to the Host platform. If the target design is intended for high
humidity or salt environments and long service life, it is recommended that the designer take
necessary precautions to guard against prolonged exposure to moisture and other
contaminants. A sealed enclosure (IP68) or potting may be required in extreme environments.
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4 SPI Interface and Sequences
4.1 SPI System Interface Overview
The SPI slave interface is currently the only supported interface for Host-to-Node communication.
NOTE: The dNode must be the only SPI slave on the bus.
The SPI slave interface provides communication with an external Host through a 7-wire interface.
The Host is the SPI master and the dNode is the SPI slave. In addition to the four standard SPI
signals, three additional signals are used to complement the SPI bus: MRQ, SRQ, and SRDY. The
additional signals are included to support dNode state transitions and bi-directional message
traffic.
The SPI signals include four that are controlled by the master and three that are controlled by the
slave.
Master-controlled Signals
n MOSI
n SCLK
n CS
n MRQ
Slave-controlled Signals
n MISO
n SRQ
n SRDY
When MRQ and SRQ are low, the remaining master controlled signals (MOSI, SCLK, and CS) must
be tri-stated. This is to prevent these signals from back-driving the dNode slave that may be in
deep sleep. When either MRQ or SRQ assert high, the master should set each of the three signals
appropriately according to their standard usage. See the following sections for timing details. No
pull-up resistors should ever be applied to any signals on the dNode.
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4.2 SPI Mode and Timing
MOSI
(from master)
1
NSS
(to slave)
MISO
(from slave)
SPCK
(CPOL = 0)
2 3 4 5 6 7 8
SPCK Cycle
(for reference)
MSB
MSB
LSB
LSB *
6 5 4 3 2 1
6 5 4 3 2 1
Figure 8. SPI Timing, CPOL = 0, CPHA = 0
4.3 Startup (Power On) Sequence
During, and immediately after Power On Reset (POR), the Host has no control of its I/O power
states. For instance, some CPUs have GPIO that tri-state or act as inputs during power up. Other
CPU brands have programmable pull-ups on its I/O and need the Host CPU to disable those pull-
ups for the Host’s GPIO to work correctly with the dNode. This setup and configuration of GPIO
takes a finite time during the Host boot process. This is detailed in the following figure.
Whereas the power-on sequence is described here, it is recommended that the Integrator not
attempt this entire startup sequence without assistance. On-Ramp Wireless offers a formal and
controlled library to help with this startup and communication interface called UNIL. This is fully
documented and released by On-Ramp Wireless. The UNIL tracks all details of the lower (physical)
and higher (messages) layers of the Host-Node communications. For more information on UNIL
see the documents referenced in chapter 1 at the beginning of this document.
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t
0
t
1
t
2
t
3
t
4
10 ms 4 ms
SRDY
SPI Bus
MRQ
Reset_N
V
BATT
< 5 sec
(Driven as appropriate)
Hi-Z
Hi-Z
Figure 9. dNode Host-driven Initial Power-up Sequence
The timing sequence shown in the figure above is described below. NOTE: The timing shown in
the figure is not to scale.
n t0 This transition shows the power-up and possible random states of Host I/O, before the
Host is able to properly configure its pins. It is strongly recommended that the selected
Host CPU be a type that tri-states its pins upon power-up.
n t1 When the Host gains control of its I/O, Reset_N should be driven low, MRQ driven low,
the SPI lines tri-stated, and SRDY from the node is expected to be low. This reset state
should be held for 10 ms.
n t2 After 10 ms, Reset_N should be released to float and MRQ is driven high.
n t3 The SPI bus should be enabled 4 ms after Reset_N is released.
n t4 SRDY going high shows the Node is fully awake and initialized. This state facilitates Host-
Node arbitration sequence and communications. t3 – t4 may take several seconds over
temperature and voltage extremes. Timeout should be 5 seconds or more.
4.4 Wake Sequence
The dNode can be awakened in two manners:
n MRQ assertion from the Host. The Host desires communications with the dNode and awakens
the dNode by asserting the MRQ line. This is a Synchronous Wake Sequence.
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n The dNode can “self-awaken” due to network events. In this case, a timer internal to the
dNode “pops” and triggers the dNode to “Wake.” When the dNode is awake it asserts its SRDY
as a matter of course to indicate to the Host (if it needs to) that it can start communicating
with the dNode while it is awake. This is an Asynchronous Wake Sequence.
4.4.1 Wake Sequence (Synchronous)
The following sequence demonstrates the timing required of the Host to awaken the dNode from
a sleep state.
Assumptions:
n The dNode has been previously Powered On and Arbitrated.
n The power (VBATT) has remained stable and the dNode has not been Reset (Reset is set to tri-
state/float).
t0t1t2t3
SRDY
SPI Bus
MRQ
Hi-Z
4 ms
(Driven as appropriate)
3 ms
Figure 10. Host-Initiated dNode Wake Sequence – SRDY Low (Synchronous)
The timing sequence shown in the figure above is described below. NOTE: The timing shown in the
figure is not to scale.
n t0 The Host decides to communicate with the dNode, checks SRDY, and determines
it is low.
n t0
à
t1 The Host ensures that SRDY has been low for at least 3 ms, then at t1, raises MRQ.
n t1
à
t2 Asserting MRQ begins internal dNode supply sequencing. The SPI bus must remain
disabled (tri-stated) for 4 ms after MRQ rises, at which point the SPI bus may be
enabled.
n t2
à
t3 After the initial assertion of MRQ, the dNode has to internally power up and
initialize its systems. When it is ready to communicate it will assert its SRDY line to
signal it is now ready for SPI interaction. From MRQ assertion until the dNode is
ready,which takes about 80 ms.
n t3 The dNode is now ready to communicate with the Host.
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4.4.2 Wake Sequence (Asynchronous)
In this scenario, the dNode is already awake due to a networking event (SRDY is already High) and
the Host wants to communicate with the dNode while it is awake. The Host asserts MRQ to ensure
that the dNode stays awake during its communication cycle.
NOTE: The timing shown in the figure is not to scale.
t0t1t2t3
SRDY
SPI Bus
MRQ
Hi-Z (Driven as appropriate)
< 250 μs> 0
Figure 11. Host-Initiated dNode Wake Sequence – SRDY High (Asynchronous)
The timing sequence shown in the figure above is described below. NOTE: The timing shown in the
figure is not to scale.
n t0 The Host decides to communicate with the dNode, checks SRDY, and determines
it is high.
n t0
à
t1 The Host must assert MRQ within 250 microseconds to avoid race conditions on
SRDY falling just after the host checks its state.
n t1
à
t2 The SPI bus must be tri-stated until after MRQ is asserted. However, the SPI bus
can be enabled immediately after MRQ is asserted and messaging can begin
immediately thereafter.
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4.5 Host-Driven Reset Sequence
If the dNode fails to communicate (or similar), it may be necessary to Reset the dNode. The
following figure shows the proper sequence to reset the device.
NOTE: Resetting the device causes it to go through a Cold Acquisition process to reacquire the
network.
Reset_N
VBATT
t0t1t2
10 ms
SRDY
SPI Bus
MRQ
4 ms
Hi-ZHi-Z
Hi-Z (Driven as appropriate)
t3
< 5 sec
Figure 12. Host-Driven Reset Sequence
The timing sequence shown in the figure above is described below. NOTE: The timing shown in
the figure is not to scale.
n t0 The host decides to reset the dNode. The SPI Bus is tristated, the MRQ is driven low, and
then Reset_N is driven low.
n t1 Reset_N is held low for 10 ms and then released back to floating.
n t2 The SPI bus should be enabled 4 ms after Reset_N is released.
n t3 SRDY going high shows the Node is fully awake and initialized. This state facilitates Host-
Node arbitration sequence and communications. t3 – t4 may take several seconds over
temperature and voltage extremes. Timeout should be 5 seconds or more.
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4.6 Host MRQ Release/dNode Allowed to Sleep Sequence
If the Host determines there are no more messages or SPI transactions required, it should disable
the interface to allow the dNode to fall back to Deep Sleep (lowest power mode). As the figure
below indicates, the SPI bus must be disabled (tri-stated) before MRQ is de-asserted. These
operations can be performed back to back.
NOTE: The timing shown in the figure is not to scale.
t
0
t
1
SRDY
SPI Bus
MRQ
Hi-Z
> 0
Figure 13. Host MRQ Release/dNode Allowed to Sleep Sequence
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5 Power States
The dNode has a number of states it runs through during its various operating modes.
General comments:
1. The dNode accepts a wide input voltage range (2.5-5.5V).
2. The dNode has low drop out (LDO) regulators that will operate 100% of the time the dNode
is powered (RESET_N signal set high or left floating by the Host).
3. There are 3.3V/1.2V Buck/Boost Switching regulators that use the wide input range to drive
key RF and Digital circuits. The 3.3V regulator is only turned on in certain active operating
states of the dNode.
The dNode tries to minimize its power consumption but is largely driven by network operating
states and ULP modes of operation. This document does not describe all of the modes in detail
but, in general, there are two main operating modes for the dNode:
n Continuous Mode
In this mode, the dNode is ON (awake) at least 50% of the time (100% of its RX cycle). The
dNode starts up, searches for the network, locks on, and Joins. In this mode, the dNode
nominally is either in RX or TX modes (radio is ON and in a high power consumption state),
or in an Idle state where the clocks and CPU are ON but the radio is OFF (moderately low
power mode). The continuous mode is usually for applications where the Host and dNode
are AC-powered and system current consumption is not an issue.
n Slotted Mode
This mode has the dNode falling into a Deep Sleep state – the lowest power state of the
dNode. In this mode, the dNode is mostly powered down – except for a couple of low power
LDO Regulators. The dNode can sleep for hours at a time if the network is configured to
allow this.
The power states are described in the following sections.
5.1 Operating States
This section describes the various operating states within the operational modes.
5.1.1 Power Off State
When the dNode is totally non-functional, the Host can set the RESET_N signal Low to
deactivate the circuitry of the dNode. This should NOT be confused with Deep Sleep states
where the dNode mostly sleeps yet maintains key network timers to wake up synchronously
with network activity. If awakened from the Power Off/Reset state, the dNode must go through
a very power-hungry search/acquisition algorithm to re-acquire the ULP network.
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5.1.2 Deep Sleep State
The dNode shuts off all its power regulators except a couple low quiescent LDO regulators.
These regulators keep a minimal amount of circuitry alive for tracking network timers, enable a
32 kHz clock, and some minor interface circuitry.
5.1.3 Oscillator Calibration State
When the dNode is in Deep Sleep state, it attempts to maintain accuracy of its low power 32 kHz
clock to enable faster network synchronizing when it wakes up. The CPU of the dNode is not
activated during this calibration state. The dNode will periodically, and briefly, Wake in a very
low power mode to calibrate its 32 kHz clock to its very accurate 26 MHz clock. This is especially
important when the temperature varies substantially causing the 32 kHz oscillator to drift. This
is illustrated in the following figure.
This plot is an example of the dNode performing a self-calibration of its 32 kHz oscillator. The
pulses represent the TCXO being turned on periodically to perform the calibration. The dNode
Wakes itself from Deep Sleep, Calibrates, and then falls back to sleep. Minimal power is
consumed during this self-calibration process. As can be seen, the dNode does this
approximately every 900 seconds.
Figure 14. dNode Oscillator Calibration: Current (Amps) vs Time (Seconds)
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5.1.4 Idle State
Idle state has various sub-states but generally refers to a state where the dNode is “awake” and
its system clock is on, the CPU is awake, but the RF is OFF.
5.1.5 RX State
The dNode turns on all its clocks, the main CPU and the RF in an RX-only state. The RF
transceiver, in RX state, consumes a moderate amount of power.
5.1.6 TX State
When the dNode transmits, it uses a variable transmit power that is correlated to its received
RSSI. In this state, the dNode is likely at its highest power states, but this is somewhat
dependent on RSSI. The worst case state (maximum power) is shown in Figure 15. This is at
approximately 20.9 dBm output power. This is the dNode’s highest power state.
5.2 System
As noted, the dNode can go through various states of Deep Sleep, Idle, RX, and TX. The plot
shown in the following figure provides a representative dNode waking up and going through
these states and transitions.
All ULPs are different and current consumption is affected by many factors.
n Network coverage. How much TX power does a dNode need to transmit its data?
n Temperature range
n Operating Voltage
n Continuous mode vs Slotted mode: What is the Uplink Interval?
n Amount of data in the data model
n Quality of Service (QoS) for data delivery
All of the factors indicated above must be examined carefully and plotted to understand the end
result in current profiles and expected battery life projections.
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Figure 15. Representative Current Consumption During Deep Sleep, Idle, RX, and TX; x16
Spreading Factor (Amps vs Seconds)
The plot shown in the figure above represents the nominal transitions for the dNode from Deep
Sleep, Idle, Receive, and Transmit states. In this case, a TX spreading factor of 16 is used. It is
important that the Host designer understand the System operating profile, operating voltages,
different operating modes of the dNode and the ultimate effect on System power consumption.
Of course, this is especially true if a battery powered device is being considered.
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6 Messaging Protocol
The details of Host/Node messaging are typically not necessary for integrators to implement,
given the functional interface provided by the ULP Node Interface Library (UNIL) (010-0066-00)
and UNIL API (010-0072-00). However, low-level understanding of the SPI protocol used may be
critical in resolving Host interface issues.
For mid-level details of the messages that may be sent over this interface, refer to ULP Node
Host Message Specification (014-0020-00).
6.1 Arbitration
Arbitration is the process a Host uses to signal to the Node that it supports the On-Ramp
Wireless bi-directional messaging protocol. The arbitration sequence is designed to reduce the
probability that an arbitrary non-Host transfer sequence can mirror a valid arbitration sequence.
Arbitration consists of both Host and Node transmitting an arbitration request/reply pair. After a
defined turn-around delay, both transmit a validation request/reply. The turn-around delay
avoids race conditions between Host and Node and provides enough time to allow ISR execution
to complete before the next SPI transfer.
If the Node does not reply to the Host request, the Host needs to wait for a turn-around delay
and retry the arbitration request.
The Host must perform the arbitration sequence before any other SPI Bus communication can
take place between the Host and the Node.
The Host must initiate this arbitration sequence on boot up. Additionally, the Host must perform
the arbitration sequence when the Node sends to the Host an arbitration message. This can
occur due to the Node going into Deep Sleep and then waking up. Since the Node requires the
arbitration sequence after waking from Deep Sleep and since the Host is not aware of when the
Node goes to Deep Sleep, the Host must be able to detect that the Node is requesting
arbitration and the Host must then reset its Host interface state machine and perform
arbitration. For more information on the Host interface SPI bus state machine, refer to section
6.3: Host Interface SPI Bus State Machine.
6.2 Message Protocol
Host-to-Node transfers use master message command pairs and Node-to-Host transfers use
slave message command pairs. Both transfers use identical command sequences with only the
encoding of the commands differing. The command sequence for a message transfer consists of
a request/acknowledgement pair followed by a defined turn-around delay and then a message
composed of a header pair and a payload.
Variable length payloads are supported by encoding the payload size in the second half of the
message request. The second half of the message reply contains the available receive buffer
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size. If the message payload size exceeds the receive buffer size, then a new request must be
made after a turn-around delay with a payload size that does not exceed the receive buffer size.
After a successful message request transfer, the Host waits a turn-around delay and then
initiates the transfer with a message header command. The payload immediately follows the
header and, if necessary, is zero padded to match the payload size indicated in the message
request.
After the payload, the Host waits a turn-around delay before proceeding with any other further
messages.
The Host interface SPI bus is a standard SPI bus (with MISO, MOSI, CS, and SCLK) with the
addition of three lines (MRQ, SRQ, and SRDY). These three additional lines are used to provide
the Host with the ability to wake up the Node over the SPI Bus as well as providing the Node
with the ability to prompt the Host to begin a SPI Bus transaction. The Node is also exceptional
in that it must be the only slave present on the SPI Bus, since MOSI, CS, and SCLK must be
undriven (tri-stated) any time that MRQ is low.
Before any message is communicated over the SPI Bus, the MRQ and SRDY lines must be high.
The Host guarantees this by pulling the MRQ line high and waiting for the Node to pull the SRDY
line high. The Host cannot proceed with SPI Bus communication until both of these lines are
high. Once MRQ and SRDY are high, the Host, being SPI Bus master, can continue with a normal
SPI Bus transaction.
When the Node wishes to communicate with the Host, it pulls the SRQ line high. The Host must
have the ability to detect this and start a SPI Bus transaction (by first pulling the MRQ high and
waiting for SRDY to go high). A standard SPI Bus transaction is described and illustrated in Figure
18.
Message exchanges between Host and Node are shown below in Figure 16.
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MRQ=1
Node
SRDY=1
Host
Slave
Request
Slave Ready
ArbREQ
ArbACK
ValREQ
ValACK
Arbitration
Request
Arbitration
Acknowledge
Validation
Acknowledge Validation
Request
MMsgREQ+Size
MMsgACK+Size
MHdrREQ
MHdrACK
Master Message
Request
Master Message
Acknowledge
Master Header
Request
Master Header
Acknowledge
Payload
Transmit
Payload
Receive
SMsgREQ+Size
SMsgACK+Size
SHdrREQ
SHdrACK
Slave Message
Request Slave Message
Acknowledge
Slave Header
Request Slave Header
Acknowledge
Payload
Transmit Payload
Receive
Repeat 6 steps above
PAYLOAD
SRQ=1
Slave
Request
Arbitration
Host-to- Node
Message
Transfer
Node-to-Host
Message
Transfer
wait
wait
wait
wait
wait
wait
wait = Turn-around Delay
MRQ=1
SRDY=1
MRQ=1
SRDY=1
wait
wait
PAYLOAD
Repeat 5 steps above
if needed
Figure 16. SPI Master and Slave Message Sequences
In each of the request/acknowledge command pairs shown, the top command is transmitted by
the Host (master) and the bottom command is transmitted by the Node (slave). The wait
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bubbles indicate a predefined turn-around delay which provides ISR processing time and avoids
race conditions between Host and Node.
6.3 Host Interface SPI Bus State Machine
This section illustrates the sequence of messages that can take place on the Host interface SPI
bus. The design and implementation of the actual state machine on the Host software is up to
the Host software designer. This diagram is provided to demonstrate the message sequence
over the SPI Bus. Note the usage of the turn-around delay, which is required in between each
step of message exchange. This delay is required by the Node and is currently defined as having
a time of 200 µs.
ARBITRATION
NIL
VALIDATION
IDLE
MMSG_REQ SMSG_REQ
MMSG_PAYLOAD SMSG_PAYLOAD
A
A
B
B
Turn-around
Delay
A
Turn-around
Delay
Turn-around
Delay
Turn-around
Delay Turn-around
Delay
B
BOOT
Exchange of Arbitration
Message
Exchange of
Validation Message Any
Non-Validation Exchange of MHDR Message Exchange of SHDR Message
Exchange of MMSG
Message
Any
Other SPI Bus
Traffic
Any
Other SPI Bus
Traffic
Exchange of SMSG
Message
Host (Master) Has
Message to Send SRQ Asserted by
Slave (Node)
Non-Arbitration
Response Unexpected
SMSG_RSP
Figure 17. Host Interface SPI Bus State Machine
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6.4 SPI Bus Timing Example
This section provides an example illustration of an exchange of messages first from master
(Host) to slave (Node) and then from slave (Node) to master (Host). Each step in the timing
sequence is described below:
SRQ
MRQ
SRDY
CS
SCLK
MISO
MOSI
6
9
5 10
11
1
2
3 4 78
Figure 18. SPI Timing Example
Note that MRQ state transitions must respect the timing requirements shown in chapter 4.
The following items pertain to the numbered bubbles above:
1. Host has a message that it desires to send to Node. The first thing that it does is drive MRQ
and CS high.
2. The Host then waits for the Node to drive SRDY high. No SPI bus transaction with the Node
can occur before this.
3. After SRDY is high, the Host can start with the SPI data transaction. This is accomplished by
driving the Node CS line low and then having the Host toggle the SCLK, and MOSI lines and
having the Node toggle the MISO line according to the data to be transferred. The SPI Host
interface specifies that first a MMsg pair is exchanged.
4. A MHdr pair is exchanged. Note that the payload of the message is appended to the MHdr.
5. The Host detects that the transaction is complete and that it does not wish to send more
messages to the Node at this time. It drives the MRQ line low. Since MRQ is low, CS, SCLK
and MOSI are tri-stated.
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6. At some time in the future, the Node desires to send a message to the Host. It indicates this
to the Host by driving SRQ high. Since SRQ is high, the Host drives MRQ and then CS high. It
then waits for SRDY to go high, which it already is.
7. The Host starts the SPI data transaction. This is accomplished by driving the Node CS line low
and then having the Host toggle the SCLK, and MOSI lines and having the Node toggle the
MISO line according to the data to be transferred. The SPI Host interface specifies that first a
SMsg pair is exchanged.
8. A SHdr pair is exchanged. Note that the payload of the message is appended to the SHdr.
9. The Node detects that the transaction is complete and that it does not wish to send more
messages to the Host at this time. It drives the SRQ line low.
10. The Host detects that SRQ has gone low and that it does not have any messages to send to
the Node. It drives the MRQ line low. Since MRQ is low, CS, SCLK and MOSI are tri-stated.
11. The Node drives the SRDY line low after MRQ goes low.
6.5 Host Message SPI Example
This section provides an example Host message exchange from master (Host) to slave (Node). In
this example, the Host is sending a version request message.
This example is a zoomed-in view of the example provided previously in Figure 18. This section
covers what happens in step 3, which includes the two SPI exchanges initiated by the Host.
With any SPI Host interface message, first an MMsg or SMsg pair must be exchanged. This pair
contains information on how big the message is (from the message originator) and how much
message queue space is available (on the message destination).
The following diagram shows such an example:
SCLK
MISO
MOSI
0 1 1 0 1 0 0 1 1 1 1 1 1 1 1 1
1 0 1 0 1 0 0 1 1 0 0 0 0 0 0 0
Figure 19. Host Message on SPI – MMsg Pair
The SPI clock edging is configurable with a polarity and phase. In order to communicate with the
Node, the SPI clock polarity must be set to “the inactive state value of SPI clock is logic level
zero” and the SPI clock phase must be set to “data is captured on the leading edge of SPI clock
and changed on the following edge of SPI clock.” This means that the data lines (both MISO and
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MOSI) are read on the SCLK rising edge and are set or cleared on the SCLK falling edge, and is
commonly referred to as CPOL=0, CPHA=0.
This illustration shows that the bit streams for MISO and MOSI are:
n MISO: 0110100111111111
n MOSI: 1010100100000100
These bits indicate:
MISO: from slave to master (01)
length of message=2 (10)
opcode=MMsgACK (1001)
buffer size=255 (11111111)
MOSI: from master to slave (10)
length of message=2 (10)
opcode =MMsgREQ (1001)
payload size=4 (00000100)
An MMsg pair or SMsg pair is immediately followed by the corresponding MHdr pair or SHdr
pair. This is illustrated below:
SCLK
MISO
MOSI
. . .
0
1
1
0
1
0
1
0
0
0
1
0
1
0
1
0
1
0
0
0
. . .
. . .
0
1
0
1
0
0
0
0
Figure 20. Host Message on SPI – MHdr Pair
For purpose of brevity, this timing diagram shows only a portion of the data exchange. The
complete bit streams for MISO and MOSI are as follows:
n MISO: 01101010000000010000000000000000000000000000000000000000000000000000
000000000000
n MOSI: 10101010000000010000100000000000000101010100000011110000111100001010
010110100101
These bits indicate:
MISO: from slave to master (01)
length of message=2 (10)
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opcode=MHdrACK (1010)
Hard coded byte=1 (00000001)
Unused Extra Data (0000…...0)
MOSI: from master to slave (10)
length of message=2 (10)
opcode =MhdrREQ (1010)
Hard coded byte=1 (00000001)
Payload:
length=8 (0000100000000000)
message type=VERSION (0001010101000000)
trailing sequence (11110000111100001010010110100101)
T
n The payload is Little Endian. The least significant byte is transmitted over SPI first.
n All MHdr and SHdr payloads are terminated by the fixed trailing sequence
11110000111100001010010110100101.
n The example above shows a message going from master to slave, thereby having a
payload in the master to slave direction appended at the end of the MhdrREQ and no
payload appended at the end of the MhdrACK.
6.6 Host Message “Connect” SPI Example
This section provides an example Host message exchange of the CONNECT message from
master/Host to slave/Node and subsequent response from the slave to the master.
The timing is similar to the timing illustrated in the previous section, but the data and length of
data is different.
The steps involved in this exchange are as follows:
The Host desires to send the CONNECT message to the Node. As described in the previous
section, this starts with an MmsgREQ/MmsgACK exchange over the SPI bus.
n MISO: 0110100111111111
n MOSI: 1010100100000110
These bits indicate:
MISO: from slave to master (01)
length of message=2 (10)
opcode=MMsgACK (1001)
buffer size=255 (11111111)
MOSI: from master to slave (10)
length of message=2 (10)
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opcode =MmsgREQ (1001)
payload size=6 (00000110)
The MMsg exchange is followed by the MHdr exchange, which includes the payload of the
CONNECT message.
n MISO: 01101010000000010000000000000000000000000000000000000000000000000000
00000000000000000000000000000000000000000000
n MOSI: 10101010000000010000110000000000001100100100000000000001000000000000
00000000000011110000111100001010010110100101
These bits indicate:
MISO: from slave to master (01)
length of message=2 (10)
opcode=MHdrACK (1010)
Hard coded byte=1 (00000001)
Unused Extra Data (0000…...0)
MOSI: from master to slave (10)
length of message=2 (10)
opcode =MhdrREQ (1010)
Hard coded byte=1 (00000001)
Payload:
length=12 (0000110000000000)
message type=CONNECT (0011001001000000)
host interface=True (00000001000000000000000000000000)
trailing sequence (11110000111100001010010110100101)
The payload of the message includes first the length, which is the number of bytes in the
payload including the length and the trailing sequence.
It is followed by the message type, which in this case is 0x4032, and corresponds with CONNECT.
The CONNECT message has a 4-byte field that is a Boolean flag specifying whether or not the
Node should send asynchronous SPI messages to the Host. To specify that the Node should send
messages to the Host, the value of 0x00000001 is used.
It is then followed by the standard fixed trailing sequence.
This message exchange is followed by a Node-initiated message exchange for the purpose of
sending an ACK of the CONNECT message to the Host. This starts with a SmsgREQ/SMsgACK
exchange over the SPI bus.
n MISO: 0110101100000100
n MOSI: 1010101111111111
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These bits indicate:
MISO: from slave to master (01)
length of message=2 (10)
opcode=SMsgACK (1011)
buffer size=255 (11111111)
payload size=4 (00000100)
MOSI: from master to slave (10)
length of message=2 (10)
opcode =SmsgREQ (1011)
buffer size=255 (11111111)
The SMsg exchange is followed by the SHdr exchange, which includes the payload of the ACK
message.
n MISO: 01101100000000010000100000000000001100000000000011110000111100001010
010110100101
n MOSI: 10101100000000010000000000000000000000000000000000000000000000000000
000000000000
These bits indicate:
MISO: from slave to master (01)
length of message=2 (10)
opcode=SHdrACK (1100)
Hard coded byte=1 (00000001)
Payload:
length=8 (0000100000000000)
message type=ACK (0011000000000000)
trailing sequence (11110000111100001010010110100101)
MOSI: from master to slave (10)
length of message=2 (10)
opcode =ShdrREQ (1100)
Hard coded byte=1 (00000001)
Unused Extra Data (0000…...0)
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7 dNode Configuration
Node Provisioning Tools (NPT) are used for Node provisioning. Complete provisioning of Nodes
involves three distinct utilities:
1. Node Software Upgrade Utility (sw_upgrade.py)
This utility is used for upgrading the Node firmware.
2. Node Flash Configuration Utility (config_node.py)
This utility is used for programming Node flash configuration parameters.
3. Node Key Provisioning Utility (provision_node_keys.py)
This utility is used for programming Node Over-the-Air (OTA) security keys.
For details about Node Provisioning Tools, refer to the NPT User Guide (010-0060-00).
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8 Antenna Diversity
The dNode supports Antenna Diversity for optimal System performance. In many cases, the
dNode and Host system are mounted in fixed locations that often experience nulls in the RF
spectrum. Antenna Diversity can help with optimization of the RX and TX paths. In marginal
coverage areas, an RF null could easily disadvantage the dNode to enforce it to transmit at a
higher TX Power (more current) or causes network loss and frequent rescanning to reacquire
the network (again, more current). These scenarios produce customer dissatisfaction as well as
increased battery drain. The dNode has two MMCX antenna ports that can be configured for
diversity through the Node Provisioning Tools (NPT). The antennas should be mounted a
minimum of 2.5” (7 cm) apart.
8.1 Antenna Design Requirements
Good antenna design and placement is also crucial to success. It is important to consider some
pertinent issues.
n Ceramic antennas can work well but may sometimes have issues. Careful testing must be
done to ensure desired gains and radiation patterns.
n The product must be researched in conjunction with the AP, its deployment, and its antenna
radiation pattern. Nominally the AP will be mounted on a tower or mountain with a
downward tilt. The dNode and System may be mounted vertically or horizontally, forcing
requirements on the dNode’s optimal radiation pattern.
n The antenna must be well-matched and with low loss between the dNode and the antenna.
It is important to follow the manufacturer’s recommendations.
n Metallic objects nearby to the antenna can affect radiation gains, patterns, and power
match. Typically anything within 4 to 5 inches can affect the match significantly, particularly
if the nearby metal is resonant at 2.4 GHz. A little pattern distortion is usually not too
concerning unless deep wide angular nulls in the antenna pattern results. Other types of
pattern distortion can be caused by absorptive losses due to lossy dielectrics nearby the
antenna, which represents real power loss dissipated as heat in the loss object. This
represents power that is completely lost and not radiated in a useful direction.
n Noisy system clocks with harmonics can fall into the operating band of the dNode and can
be picked up by the antennas degrading sensitivity or causing Electromagnetic Compatibility
(EMC) regulatory failures.
8.2 Diversity Considerations
The operating frequency of the dNode is the ISM 2.4GHz band. This has a wavelength of 12.3 cm
in air. For optimal null/peak diversity detection, the antennas must be separated by at least 2.5”
(5 cm). It is a good idea on the diversity antenna to orient it 90 degrees from the main antenna in
order to improve on polarization diversity between antennas in addition to spatial de-correlation.
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9 Regulatory Considerations
The dNode uses two MMCX connectors for its RF ports. On-Ramp Wireless provides FCC/IC
modular approval certification as well as ETSI certification for the dNode. The dNode was
certified on an On-Ramp Wireless application platform known as the eHost. These documents
and results are available to System Integrators to ensure that the product can be certified.
Additionally, On-Ramp Wireless has prepared certification guidelines on how to use the
software and system tools required for certification. Some markets (such as FCC/IC) are fairly
straight forward for certification and are largely TX Spectrum-based. Other markets (such as
ETSI) require a much more sophisticated FER process involving an Access Point and Quick Start
System. These procedures are defined in the document entitled Node FCC/IC/ETSI EMC
Compliance Test Procedures (009-0021-00). This document also includes hints and
recommendations to help make the process as easy as possible. For more information about this
document, see the list of documents referenced in Chapter 1: Overview.
9.1 Block Diagram
Some regulatory domains require a block diagram of the module for their documentation similar
to that shown in the following figure.
Figure 21. dNode Block Diagram
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9.2 Certifications
The dNode is designed to meet regulations for world-wide use. It is has modular approval
certification in the United States and Canada, and ETSI certification in Europe. The certifications
currently achieved are listed in the following table.
Table 8. dNode Certifications
Country Certifying Agency Certification(s)
United States Federal
Communications
Commission (FCC)
n 15.207 for powerline conducted emissions.
n 15.215 for RF TX bandwidth, power, conducted
and radiated emissions.
Canada Industry Canada (IC) n RSS210e, includes FCC tests and IC-specific
tests (RX radiated emissions).
Europe European
Telecommunications
Standards Institute
(ETSI)
n 300 440-1 and 440-2, ETSI Emissions.
n 301 489-1, ETSI Immunity.
Additional details can be found in the document entitled Node FCC/IC/ETSI EMC Compliance
Test Procedures (009-0021-00) referenced in Chapter 1: Overview.
The integrator of the final product is often required to do additional compliance tests. The
integration application and market will determine specifics. The integrator is advised to consult
with local experts in compliance certifications for complete information.
n FCC/IC
The dNode is Single-Modular Certified, therefore the final product may only need Class B
unintentional radiator and powerline conducted emissions tests. This should be done with
the actual production antenna.
n ETSI
Europe’s system is a self-declaration system. There are no documents to submit or
certification grants to obtain. One must have the passing test results available for all
applicable requirements at any time if challenged.
n Other countries will vary.
9.3 FCC Warnings
This device complies with part 15 of the Federal Communications Commission (FCC) Rules.
Operation is subject to the following two conditions:
1. This device may not cause harmful interference.
2. This device must accept any interference received, including interference that may cause
undesired operation.
Changes or modifications not expressly approved by the manufacturer could void the user’s
authority to operate the equipment.
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NOTE: This equipment has been tested and found to comply with the limits for a Class B
digital device, pursuant to Part 15 of the FCC Rules. These limits are designed to
provide reasonable protection against harmful interference in a residential
installation.
WARNING: This equipment generates, uses, and can radiate radio frequency energy. If not
installed and used in accordance with the instructions, this equipment may cause
harmful interference to radio communications. However, there is no guarantee
that interference will not occur in a particular installation. If this equipment does
cause harmful interference to radio or television reception, which can be
determined by turning the equipment off and on, the user is encouraged to try to
correct the interference by one or more of the following measures:
n Re-orient or relocate the receiving antenna.
n Increase the separation between the equipment and receiver.
n Connect the equipment into an outlet on a circuit different from that to which
the receiver is connected.
n Consult the dealer or an experienced radio/TV technician for help.
9.4 IC Warnings
The installer of this radio equipment must ensure that the antenna is located or pointed so that
it does not emit RF field in excess of Health Canada limits for the general population. Consult
Safety Code 6 which is obtainable from Health Canada’s website http://www.hc-sc.gc.ca/index-
eng.php.
Operation is subject to the following two conditions:
1. This device may not cause harmful interference.
2. This device must accept any interference received, including interference that may cause
undesired operation.
To reduce potential radio interference to other users, select the antenna type and its gain so
that the equivalent isotropically radiated power (EIRP) is not more than that permitted for
successful communication.
Canadian Two Part Warning Statement:
This device complies with Industry Canada licence-exempt RSS standard(s). Operation is subject
to the following two conditions: (1) this device may not cause interference, and (2) this device
must accept any interference, including interference that may cause undesired operation of the
device.
Le présent appareil est conforme aux CNR d'Industrie Canada applicables aux appareils radio
exempts de licence. L'exploitation est autorisée aux deux conditions suivantes : (1) l'appareil ne
doit pas produire de brouillage, et (2) l'utilisateur de l'appareil doit accepter tout brouillage
radioélectrique subi, même si le brouillage est susceptible d'en compromettre le
fonctionnement.
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9.5 ETSI Warnings
None known.
9.6 Usage
FCC ID: XTE-ULPD100. IC: 8655A-ULPD100. This device is only authorized for use in fixed and
mobile applications. To meet FCC and other national radio frequency (RF) exposure
requirements, the antenna for this device must be installed to ensure a separation distance of at
least 20cm (8 inches) from the antenna to a person.
9.6.1 Note to Integrators
A label showing the FCC ID and IC designators, listed above, must be affixed to the exterior of
any device containing the dNode (if the dNode is not visible). The exterior label must include:
Contains FCC ID: XTE-ULPD100, IC: 8655A-ULPD100.
9.6.2 RF Exposure Statement
The air interface supports operation on channels in the 2402 MHz – 2476 MHz range for FCC/IC
regulatory domains and 2402 MHz – 2481 MHz for the ETSI regulatory domain.
Before the ULP dNode becomes operational, it must undergo a commissioning procedure,
during which critical information required for operation is entered into the device and stored in
non-volatile storage. It is during the initial commissioning procedure that the regulatory domain,
under which the device will operate, is set. Subsequent configuration of the device during
operation is checked against the commissioned regulatory domain and non-permitted channels
or transmit power levels are rejected and the device will not transmit until a permissible
configuration per the commissioned regulatory domain is set.
9.7 Antennas
This dNode has been certified to operate with the antenna listed below. To adhere to these
certifications requires the antenna to have a peak gain of 2 dBi or less and to have monopole
construction (Omnidirectional pattern). Antennas that do not have monopole construction or a
gain greater than 2 dBi are strictly prohibited for use with the dNode, per On-Ramp Wireless’
EMC certifications. The required antenna impedance is 50 ohms.
Table 9. On-Ramp Wireless EMC Certified Antenna
Manufacturer Part Number Gain Type Connector Comment
L-com HG2402RD-RSF 2 dBi Monopole RP-SMA Plug MMCX Plug to RP-SMA
Jack adaptor required.
Customers are free to follow one of two paths in their final product:
n Customers can use On-Ramp Wireless’ antenna type with a gain ≤ 2 dBi. This path allows
customers to use On-Ramp Wireless’ certifications. While ideal from the perspective of
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program cost and schedule, the ability to reuse this antenna is highly dependent on the
application.
n Customers can recertify the final product with any antenna type and gain desired. In the
case of FCC/IC EMC certifications, it is almost always required for the final product to be
recertified with the dNode. If this is the case, note that the recertification is the required
time to introduce the final product’s actual antenna.
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10 Design Considerations for the Host
The dNode has two 10-pin Single Inline Package (SIP) headers that allow for two Host mounting
methods: Socketed and Direct Solder.
10.1 Host Mounting Method: Socketed
The Socketed Host mounting method is preferred since it permits easy insertion, removal, and
network provisioning of the dNode on a separate Host. It is important to follow some layout
constraints and the recommended design guidelines of the socket manufacturer. It is important
to use a high quality socket with very low impedance. Some less expensive sockets have been
found to generate high resistance on their pins over time. This is especially true with the all-
important Vbatt and Ground pins of the dNode. A representative high quality socket has been
found to be: Mill-Max PN 834-43-010-10-001000. For details about Mill-Max Series 834/835
series SIP sockets, refer to www.mill-max.com.
10.1.1 Host PCB Land Pattern
Figure 22. Host PCB Land Pattern – Mill-Max Socket
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10.1.2 Pad Stack for Mill-Max Series 834
Paste In Hole (PIH) soldering technique allows for installation of the Mill-Max 834 series
connectors during the SMD reflow process. As shown below, the component side pad is a large
rounded rectangular (100x60 mils) and all other pads are 60 mil round pads, with all pads using
a plated drill hole of 46 mils.
Figure 23. Pad Stack for Mill-Max Series 834
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10.2 Host Mounting Method: Direct Solder
The Direct Solder method of mounting the dNode gives little flexibility in insertion/removal but
is the least expensive and can provide Low resistance on the Vbatt/Ground paths. PCB layout
considerations are provided below.
.100 [2.54] (TYP)
.844 [21.44] (TYP)
.040 [1.02] DIA (TYP) x20
Optional square
pads to indicate
Pin 1 of connectors.
Same drill diameter.
Optional square
pads to indicate
Pin 1 of connectors.
Same drill diameter.
Optional
Stencil Marks
Figure 24. Host PCB Land Pattern – Direct Solder
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11 Errata
Degraded RF Channels
The dNode uses a Channel scheme such as the following:
n Channel 1 = 2402 MHz and each successive channel is 1.99 MHz offset to that Channel 1.
n Channel 2 = 2403.99 MHz
n Channel 3 = 2405.98 MHz
n Etc.
The dNode uses a 26 MHz reference clock for processing and for the direct conversion radio. It
has been found that 26 MHz harmonics can create strong tones that cause some RF sensitivity
degradation on these harmonic channels.
n 93*26 MHz = 2418 MHz. This affects channel 9.
n 94*26 MHz = 2444 MHz. This affects channel 22.
n 95*26 MHz = 2470 MHz. This affects channel 35.
System integrators should NOT use these 3 channels as dNode RX sensitivity can be degraded by
a nominal 3-10 dB.
Refer to On-Ramp Wireless Issues #2319 and #2616.
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Appendix A Abbreviations and Terms
Abbreviation/Term Definition
AGC Automatic Gain Control
ALC Automatic Level Control
AP Access Point (this product)
API Application Programming Interface
ASIC Application-Specific Integrated Circuit
BOM Bill of Materials
BW Bandwidth
CMOS Complementary Metal-Oxide-Semiconductor
CPOL Clock Polarity (for SPI)
CPU Central Processing Unit
DFS Dynamic Frequency Selection
dNode Third generation of the ULP wireless module that integrates with OEM
sensors and communicates sensor data to an Access Point.
DPLL Digital Phase-Locked Loop
EMC Electromagnetic Compatibility
ESD Electrostatic Discharge
ETSI European Telecommunications Standards Institute
EVM Error Vector Magnitude
FCC Federal Communications Commission
FER Frame Error Rate
GND Ground
GPIO General Purpose Input/Output
HBM Human Body Model
IC Industry Canada
IIP3 Input Third-Order Intercept Point
LDO Low Drop Out
LNA Low Noise Amplifier
LO Local Oscillator
microNode Second generation of the ULP wireless module that integrates with
OEM sensors and communicates sensor data to an Access Point.
MISO Master Input, Slave Output
MM Machine Model
MOSI Master Output, Slave Input
MRQ Master Request
MSL Moisture Sensitivity Level
Node The generic term used interchangeably with eNode, microNode, or
dNode.
NPT Node Provisioning Tools
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Abbreviation/Term Definition
OTA Over-the-Air
PA Power Amplifier
PAPR Peak-to-Average Power Ratio
PCB Printed Circuit Board
POR Power On Reset
QoS Quality of Service
RF Radio Frequency
RFIC Radio Frequency Integrated Circuit
RoHS Restriction of Hazardous Substances
RSSI Receive Signal Strength Indicator
RT Remote Terminal
RTC Real Time Clock
RX Receive/Receiver
SCLK Serial Clock
SMT Surface Mount Technology
SNR Signal-to-Noise Ratio
SPI Synchronous Peripheral Interface
SRDY Slave Ready
SRQ Slave Request
TX Transmit/Transmitter
UART Universal Asynchronous Receiver/Transmitter
ULP Ultra-Link Processing™. On-Ramp Wireless proprietary wireless
communication technology.
UNIL ULP Node Interface Library
VCO Voltage Controlled Oscillator
VCTCXO Voltage Controlled Temperature Compensated Crystal Oscillator
VSWR Voltage Standing Wave Ratio
XO Crystal Oscillator
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Appendix B dNode Mechanical Drawing
Figure 25. dNode Mechanical Dimensions