Texas Instruments SWRU294 User manual

SWRU294
SmartRF Transceiver
Evaluation Board
User’s Guide

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Table of Contents
TABLE OF CONTENTS.................................................................................................................. 3
LIST OF FIGURES.......................................................................................................................... 5
LIST OF TABLES............................................................................................................................ 5
1INTRODUCTION .................................................................................................................. 6
2ABOUT THIS MANUAL ....................................................................................................... 6
3ACRONYMS AND ABBREVIATIONS................................................................................. 7
4GETTING STARTED............................................................................................................ 8
4.1 SMARTRF STUDIO 7............................................................................................................ 8
4.2 INSTALLING SMARTRF STUDIO AND USB DRIVERS................................................................ 8
4.2.1 Cebal USB driver .............................................................................................................. 8
4.2.2 Virtual COM port USB driver............................................................................................. 9
5USING THE SMARTRF TRANSCEIVER EVALUATION BOARD.................................... 10
5.1 ABSOLUTE MAXIMUM RATINGS............................................................................................ 11
6SMARTRF TRANSCEIVER EVALUATION BOARD OVERVIEW.................................... 12
6.1 USB MCU........................................................................................................................ 12
6.1.1 SmartRF Mode................................................................................................................ 14
6.1.2 UART Mode..................................................................................................................... 14
6.1.3 Disabled Mode ................................................................................................................ 15
6.2 MSP430 MCU ................................................................................................................. 16
6.3 POWER SOURCES ............................................................................................................. 16
6.3.1 Battery Power.................................................................................................................. 17
6.3.2 USB Power...................................................................................................................... 17
6.3.3 External Power Supply.................................................................................................... 18
6.3.4 MSP-FET Power ............................................................................................................. 19
6.4 LCD................................................................................................................................. 19
6.5 ACCELEROMETER.............................................................................................................. 19
6.6 AMBIENT LIGHT SENSOR.................................................................................................... 19
6.7 SERIAL FLASH................................................................................................................... 19
6.8 BUTTONS.......................................................................................................................... 20
6.9 LEDS............................................................................................................................... 20
6.9.1 General Purpose LEDs ................................................................................................... 20
6.9.2 USB LED......................................................................................................................... 20
6.10 EM CONNECTORS............................................................................................................. 21
6.11 BREAKOUT HEADERS AND JUMPERS................................................................................... 22
6.11.1 EM I/O breakout headers................................................................................................ 23
6.11.2 MSP430 I/O breakout...................................................................................................... 23
6.12 CURRENT MEASUREMENT JUMPERS................................................................................... 26
7CONNECTING AN EXTERNAL MCU TO SMARTRF TRXEB.......................................... 28
7.1 DISABLE SMARTRF TRXEB MCUS..................................................................................... 28
7.2 SELECT POWER SOURCE.................................................................................................... 28
7.2.1 Power external MCU from SmartRF TrxEB.................................................................... 28
7.2.2 Power SmartRF TrxEB from external power source....................................................... 29
7.3 CONNECT SIGNALS ............................................................................................................ 29
7.3.1 Common signals ............................................................................................................. 29
7.3.2 Transceiver GPIO signals............................................................................................... 30
8USING SMARTRF STUDIO WITH COMBO EMS AND SMARTRF TRXEB ................... 31
9SMARTRF TRXEB REV. 1.3.0........................................................................................... 32
9.1 BOARD OVERVIEW............................................................................................................. 32
9.2 SOFTWARE CONSIDERATIONS............................................................................................ 32

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9.2.1 Virtual COM port over USB............................................................................................. 32
9.2.2 Accelerometer................................................................................................................. 32
9.3 USB MCU PIN-OUT........................................................................................................... 33
9.4 MSP430 MCU PIN-OUT..................................................................................................... 33
10 SMARTRF TRXEB REV. 1.5.0........................................................................................... 34
10.1 BOARD OVERVIEW............................................................................................................. 34
10.2 CHANGES FROM REV.1.3.0................................................................................................ 34
10.2.1 RC filter on USB MCU reset line..................................................................................... 34
10.2.2 Accelerometer................................................................................................................. 34
10.2.3 Silk print........................................................................................................................... 35
10.3 USB MCU PIN-OUT........................................................................................................... 35
10.4 MSP430 MCU PIN-OUT..................................................................................................... 35
11 UPDATING THE FIRMWARE............................................................................................ 36
11.1 FORCED BOOT RECOVERY MODE....................................................................................... 37
12 FREQUENTLY ASKED QUESTIONS ............................................................................... 38
13 REFERENCES ................................................................................................................... 39
14 DOCUMENT HISTORY...................................................................................................... 40

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List of Figures
Figure 1 –Install virtual COM port USB driver using the Windows Hardware Wizard.................... 9
Figure 2 –SmartRF TrxEB (rev. 1.5.0) with EM connected.......................................................... 10
Figure 3 –SmartRF TrxEB architecture........................................................................................ 12
Figure 4 –Flow chart of the USB MCU bootloader and standard firmware.................................. 13
Figure 5 –UART lines connected between the USB MCU and the onboard MSP430 MCU. ...... 15
Figure 6 –Main power selection header (P17) and power switch (P5)......................................... 16
Figure 7 –P17 jumper settings to power TrxEB using batteries................................................... 17
Figure 8 –P17 jumper settings to power TrxEB via the USB cable.............................................. 17
Figure 9 –P17 jumper settings to power TrxEB using external power supply.............................. 18
Figure 10 –Powering TrxEB via the external power supply connector (P201)............................. 18
Figure 11 –P17 jumper settings to power EB using a MSP-FET ................................................. 19
Figure 12 –SmartRF TrxEB EM connectors RF1 and RF2.......................................................... 21
Figure 13 –SmartRF TrxEB I/O breakout overview...................................................................... 22
Figure 14 –I/O connector P25A-E PCB layout ............................................................................. 23
Figure 15 –MSP430 I/O breakout on SmartRF TrxEB................................................................. 23
Figure 16 –Current measurement jumpers .................................................................................. 26
Figure 17 –Current measurement setup ...................................................................................... 26
Figure 18 –Switch and jumper settings to disable both SmartRF TrxEB MCUs.......................... 28
Figure 19 –Power external MCU board by connecting it to IO_PWR and GND .......................... 28
Figure 20 –P7 with strapping to connect external MCU to SmartRF TrxEB ................................ 30
Figure 21 –Signal strapping for SmartRF Studio combo EM support on SmartRF TrxEB........... 31
Figure 22 –Block diagram for SmartRF Studio combo EM support on SmartRF TrxEB.............. 31
Figure 23 –SmartRF TrxEB revision 1.3.0 overview.................................................................... 32
Figure 24 –Accelerometer axes on SmartRF TrxEB rev. 1.3.0.................................................... 32
Figure 25 –SmartRF TrxEB revision 1.5.0 overview.................................................................... 34
Figure 26 –Accelerometer axes on SmartRF TrxEB rev. 1.5.0.................................................... 34
Figure 27 –Correct silk print for MCLK and SMCLK test points................................................... 35
Figure 28 –Firmware upgrade steps in SmartRF Studio.............................................................. 36
Figure 29 –Enter forced boot recovery mode............................................................................... 37
List of Tables
Table 1 –Available features on the SmartRF TrxEB ...................................................................... 6
Table 2 –Supply voltage: Recommended operating conditions and absolute max. ratings ........ 11
Table 3 –Temperature: Recommended operating conditions and storage temperatures ........... 11
Table 4 –SmartRF TrxEB operating modes................................................................................. 14
Table 5 –Data rates supported by the USB MCU in UART Mode................................................ 15
Table 6 –USB LED state descriptions.......................................................................................... 20
Table 7 –EM connector RF1 pin-out............................................................................................. 21
Table 8 –EM connector RF2 pin-out............................................................................................. 22
Table 9 –MSP430 Port 1-5 pin-out............................................................................................... 24
Table 10 –MSP430 Port 6-10 pin-out........................................................................................... 25
Table 11 –Component/Power segment overview......................................................................... 27
Table 12 –Strapping overview to connect common signals to an external MCU......................... 29
Table 13 –Strapping overview to transceiver GPIO to an external MCU..................................... 30
Table 14 –Signal strapping for SmartRF Studio combo EM support on SmartRF TrxEB............ 31
Table 15 –USB MCU pin-out on SmartRF TrxEB rev. 1.3.0 ........................................................ 33
Table 16 –MSP430 miscellaneous signal pin-out ........................................................................ 33

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1 Introduction
The SmartRF Transceiver Evaluation Board (SmartRF TrxEB or simply EB) is the motherboard in
many development kits for Low Power RF transceiver devices from Texas Instruments. The
board has a wide range of features, listed in Table 1 below.
Component
Description
MSP430 MCU
The Ultra-low Power MSP430 serves as a platform for software
development, testing and debugging.
Full-speed USB 2.0 interface
Easy plug and play access to full transceiver control using
SmartRF™ Studio PC software. Integrated serial port over USB
enables communication between onboard MSP430 and PC.
64x128 pixels serial LCD
Big LCD display for demo use and user interface development.
LEDs
Four general purpose LEDs for demo use or debugging.
Serial Flash
External flash for extra storage, over-the-air upgrades and more.
Buttons
Five push-buttons for demo use and user interfacing.
Accelerometer
Three-axis highly configurable digital accelerometer for application
development and demo use.
Light Sensor
Ambient Light Sensor for application development and demo use.
Breakout pins
Easy access to GPIO pins for quick and easy debugging.
Table 1 –Available features on the SmartRF TrxEB
2 About this manual
This manual contains reference information about the SmartRF TrxEB.
Chapter 4 will give a quick introduction on how to get started with the SmartRF TrxEB. It
describes how to install SmartRF Studio and to get the required USB drivers for the evaluation
board. Chapter 5 briefly explains how the EB can be used throughout a project’s development
cycle. Chapter 6 gives an overview of the various features and functionality provided by the
board.
Chapter 9 and 10 provide additional details about the different revisions of SmartRF TrxEB,
revision 1.3.0 and 1.5.0, respectively. Chapter 11 gives details on how to update the EB firmware,
while a troubleshooting guide is found in chapter 12.
Appendices A, B and C contain the schematics for the different versions of SmartRF TrxEB.
The PC tools SmartRF Studio and SmartRF Flash Programmer have their own user manual.
See chapter 13 for references to relevant documents and web pages.

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3 Acronyms and Abbreviations
ACM Abstract Control Model
ALS Ambient Light Sensor
CEBAL CC Evaluation Board Abstraction Layer
CDC Communication Device Class
CTS Clear to Send
CW Continuous Wave
DK Development Kit
DUT Device Under Test
EB Evaluation Board
EM Evaluation Module
IC Integrated Circuit
I/O Input/Output
KB Kibi Byte (1024 byte)
LCD Liquid Crystal Display
LED Light Emitting Diode
LPRF Low Power RF
MCU Micro Controller
MISO Master In, Slave Out (SPI signal)
MOSI Master Out, Slave In (SPI signal)
NA Not Applicable / Not Available
NC Not Connected
PER Packet Error Rate
RF Radio Frequency
RX Receive
RTS Request to Send
SoC System on Chip
SPI Serial Peripheral Interface
TI Texas Instruments
TrxEB Transceiver Evaluation Board
TX Transmit
TRX Transmit / Receive
UART Universal Asynchronous Receive Transmit
USB Universal Serial Bus

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4 Getting Started
Before connecting the SmartRF TrxEB to the PC via the USB cable, it is highly recommended to
perform the steps described below.
4.1 SmartRF Studio 7
SmartRF Studio is a PC application developed for configuration and evaluation of many of the
RF-IC products from Texas Instruments. The application is designed for use with SmartRF
Evaluation Boards, such as SmartRF TrxEB, and runs on Microsoft Windows operating systems.
SmartRF Studio lets you explore and experiment with the RF-ICs as it gives full overview and
access to the devices’ registers to configure the radio and has a control interface for simple radio
operation from the PC.
This means that SmartRF Studio will help radio system designers to easily evaluate the RF-IC at
an early stage in the design process. It also offers a flexible code export function of radio register
settings for software developers.
The latest version of SmartRF Studio can be downloaded from the Texas Instruments website [1],
where you will also find a complete user manual.
4.2 Installing SmartRF Studio and USB drivers
Before your PC can communicate with the SmartRF TrxEB over USB, you will need to install the
USB drivers for the EB. The latest SmartRF Studio installer [1] includes USB drivers both for
Windows x86 and Windows x64 platforms.
After you have downloaded SmartRF Studio from the web, extract the zip-file, run the installer
and follow the instructions. Select the complete installation to include the SmartRF Studio
program, the SmartRF Studio documentation and the necessary drivers needed to communicate
with the SmartRF TrxEB.
4.2.1 Cebal USB driver
SmartRF PC software such as SmartRF Studio uses a proprietary USB driver, Cebal, to
communicate with evaluation boards. Connect your SmartRF TrxEB to the computer with a USB
cable and turn it on. If you did a complete install of SmartRF Studio, Windows will recognize the
device automatically and the SmartRF TrxEB is ready for use!
For more information regarding the USB drivers, please consult the SmartRF Studio
documentation, the USB driver installation guide [2] or chapter 11.
NOTE: The SmartRF TrxEB must be in “SmartRF Mode” in order to be recognized by the
drivers installed with the SmartRF Studio installer. The EB is in SmartRF Mode when
hardware switches S1 and S2 are in positions “SmartRF” and “Enable”, respectively. See
section 6.1 for more information about the SmartRF TrxEB operating modes.

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4.2.2 Virtual COM port USB driver
If you are using SmartRF TrxEB in UART Mode (see section 6.1.2), a standard driver for a virtual
COM port over USB is used (USB CDC-ACM). If you did a complete install of SmartRF Studio,
Windows will recognize the device automatically. If prompted with the Windows Hardware
Wizard, select “Install the software automatically (recommended)” and click next to finish the
installation. The SmartRF TrxEB is now ready for use!
If the SmartRF TrxEB CDC-ACM driver is not found by the Hardware Wizard, make sure you
have installed the latest version of SmartRF Studio [1]. In the Windows Hardware Wizard, select
“Install from a list or specific location (Advanced)”. You will see below window.
Figure 1 –Install virtual COM port USB driver using the Windows Hardware Wizard
The driver for the Virtual COM Port (VCP) is typically located in the directory C:\Program
Files\Texas Instruments\SmartRF Tools\Drivers\vcp, where C:\Program Files\Texas
Instruments\SmartRF Tools\ is the root installation directory for SmartRF Tools such as SmartRF
Studio. The path may be different if you have chosen a different installation directory for SmartRF
Studio.
If the above fails, select “Don’t Search. I will choose the driver to install.” A new window will open,
asking for a location of where the drivers can be found. Locate the trxeb_cdc_uart.inf file and
select that driver for installation.
NOTE: The SmartRF TrxEB must be in “UART Mode” in order to be recognized as a virtual
COM port. The EB is in UART Mode when hardware switches S1 and S2 are in positions
“UART” and “Enable”, respectively. See section 6.1 for more information about the SmartRF
TrxEB operating modes.

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5 Using the SmartRF Transceiver Evaluation Board
The SmartRF TrxEB is a flexible test and development platform that works together with RF
Evaluation Modules from Texas Instruments.
An Evaluation Module is a small RF module with RF chip, balun, matching filter, SMA antenna
connector and I/O connectors. The modules can be plugged into the SmartRF TrxEB which lets
the PC take direct control of the RF device on the EM over the USB interface.
Currently, SmartRF TrxEB supports:
- CC1120EM
- CC1121EM
- CC2520EM
- CC1101EM
- CC1100EM
- CC1100EEM
- CC110LEM
- CC113LEM
- CC115LEM
SmartRF TrxEB is included in e.g. the CC1120 development kit. Some of the above EMs comes
in variants combined with a RF front-end such as CC1190 or CC2590/CC2591. Such variants are
called combo EMs and are also supported by the SmartRF TrxEB. See chapter 8 for details on
how to use SmartRF TrxEB rev. ≤1.5.0 to control a combo EM using SmartRF Studio.
Figure 2 –SmartRF TrxEB (rev. 1.5.0) with EM connected

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The PC software that controls the SmartRF TrxEB + EM is SmartRF Studio. Studio can be used
to perform several RF tests and measurements, e.g. to set up a CW signal and send/receive
packets.
The EB+EM can be of great help during the whole development cycle for a new RF product.
- Perform comparative studies. Compare results obtained with EB+EM with results from
your own system.
- Perform basic functional tests of your own hardware by connecting the radio on your
board to SmartRF TrxEB. SmartRF Studio can be used to exercise the radio.
- Verify your own software with known good RF hardware, by simply connecting your own
microcontroller to an EM via the EB. Test the send function by transmitting packets from
your SW and receive with another board using SmartRF Studio. Then transmit using
SmartRF Studio and receive with your own software.
- The SmartRF TrxEB can also be used as a debugger interface to the SoCs from IAR
Embedded Workbench for 8051.
- Develop code to the onboard MSP430 MCU and use the SmartRF TrxEB as a
standalone board without PC tools.
5.1 Absolute maximum ratings
The minimum and maximum operating supply voltages and absolute maximum ratings for the
active components onboard the SmartRF TrxEB are summarized in Table 2. Table 3 lists the
recommended operating temperature and storage temperature ratings. Please refer to the
respective component’s datasheet for further details.
Component
Operating voltage
Absolute max. rating
Min. [V]
Max. [V]
Min. [V]
Max. [V]
USB MCU [3]
+3.0
+3.6
-0.3
+3.9
MSP 430 MCU [6]
+1.8
+3.6
-0.3
+4.1
LCD [7]
+3.0
+3.3
-0.3
+3.6
Accelerometer [8]
+1.7
+3.6
-0.3
+3.6
Ambient light sensor [9]
+2.3
+5.5
NA
+6
Serial Flash [10]
+2.7
+3.6
-0.4
+4.0
Table 2 –Supply voltage: Recommended operating conditions and absolute max. ratings
Component
Operating temperature
Storage temperature
Min. [˚C]
Max. [˚C]
Min. [˚C]
Max. [˚C]
USB MCU [3]
0
+85
-50
+150
MSP 430 MCU [6]
-40
+85
-55
+105
LCD [7]
-20
+70
-30
+80
Accelerometer [8]
-40
+85
-40
+125
Ambient light sensor [9]
-40
+85
-40
+85
Serial Flash [10]
-40
+85
-65
+150
Table 3 –Temperature: Recommended operating conditions and storage temperatures

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6 SmartRF Transceiver Evaluation Board Overview
SmartRF TrxEB acts as the motherboard in several development kits for Low Power RF ICs from
Texas Instruments. The board has several user interfaces and connections to external interfaces,
allowing fast prototyping and testing of both software and hardware.
This chapter will give an overview of the general architecture of the board and describe the
available I/O. The following sub-sections will explain the I/O in more detail. Pin connections
between the evaluation board I/O and EM can be found in section 6.10.
EM
Serial
Flash LCD
USB
LED
Buttons Accelerometer
Light
Sensor
JTAG
debug
USB
MSP430F5438A
controller
USBController
(CC2511)
UART
AlternativeSPI (USCIB1)/UART(USCIA0)
SPI (USCIB0)
UART(1.6.0+ only)
GPIO
SPI(USCIA2)
SPI(USCIB2)
LEDs
Figure 3 –SmartRF TrxEB architecture
6.1 USB MCU
The USB MCU is the CC2511F32 from Texas Instruments. Please see the CC2511 product page
[3] on the TI web for detailed information about this controller. The recommended operating
condition for the CC2511 is a supply voltage between 3.0 V and 3.6 V. The min (max) operating
temperature is 0 (+85) ˚C.
The USB controller is programmed with a bootloader and the standard SmartRF TrxEB firmware
when it is shipped from the factory. A flow chart over the USB MCU bootloader and standard
firmware is shown in Figure 4.
NOTE: Signal names used in this user’s guide and in the SmartRF TrxEB schematics, are
named “as seen” from the onboard MSP430 MCU. E.g. signal name “P1_3” refers to the
signal connected to MSP430 port 1, pin 3.

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HoldMSP430 &
EMinreset Forcedrecoveryor no/invalidapplication ReleaseMSP430 & EMreset
RecoveryModeLaunchapplication
No
Determineoperating
mode(S1/S2)
SmartRFMode
ReleaseEM
reset ReleaseMSP430 & EMreset
UARTMode DisabledMode
Power-on-Reset
EnableCebal
USBinterface
Yes
USBMCUStandardApplication
USBMCUBootloader
EnableCebal
USBinterface
ReleaseMSP430
& EMreset
EnableCDC-ACM
USBinterface
S1/S2 change
Enter low-power
mode
SmartRF
UART
Disabled
Figure 4 –Flow chart of the USB MCU bootloader and standard firmware
When the bootloader starts running, it will check for a valid application in the CC2511 flash
memory. If detection is successful, the application is started and the board can be operated
normally. If no application is detected (e.g. blank flash or firmware upgrade failed) the USB LED
(D6) will start blinking rapidly –indicating failure. See section 6.9.2 for more details on USB LED
states.
The USB MCU bootloader will allow programming/upgrading of the USB MCU firmware over the
USB interface. No additional hardware or programmers are needed. Both SmartRF Studio and
SmartRF Flash Programmer [4] can be used for this purpose. Please refer to chapter 11 for
details.
The standard firmware application has three operating modes, controlled by hardware switches
S1 and S2. The three modes are named “SmartRF Mode”, “UART Mode” and “Disabled Mode”.
Table 4 shows which S1 and S2 positions that give the different operation modes. The following
sections will discuss the different operating modes in more detail.

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S2
S1
Operating Mode
Key features
Enable
SmartRF
SmartRF Mode
- Cebal USB interface
- MSP430 disabled
- Control RF-IC using
SmartRF PC software
Enable
UART
UART Mode
- CDC-ACM USB interface
- MSP430 enabled
- UART bridge between PC
and MSP430
- Control RF-IC using
MSP430 or external MCU
Disable
x
Disabled Mode
- USB interface disabled
- MSP430 enabled
- Control RF-IC using
MSP430 or external MCU
Table 4 –SmartRF TrxEB operating modes
6.1.1 SmartRF Mode
SmartRF Mode is the standard operating mode and is obtained by setting hardware switches S1
and S2 on the EB to “SmartRF” and “Enable”, respectively (see Table 4).
In SmartRF mode the EB is recognized over USB as a Cebal device, enabling PC software like
SmartRF Studio to configure and control the RF-IC connected to the EB’s EM connectors.
The onboard MSP430 microcontroller is in this operating mode held in reset by the USB MCU.
6.1.2 UART Mode
UART Mode is obtained by setting hardware switches S1 and S2 on the EB to “UART” and
“Enable”, respectively (see Table 4).
In UART mode, the EB is recognized over USB as a virtual serial port (CDC-ACM). The USB
MCU works as a UART bridge between the onboard MSP430 and the PC. The hardware
connection between the USB MCU and the MSP430 is shown in Figure 5. The supported data
rates are listed in Table 5.
It is not possible to use SmartRF Studio or other PC software to communicate with a connected
RF-IC when operating in UART Mode. To communicate with a connected RF-IC, the onboard
MSP430 or an external MCU must be programmed with custom firmware. Please refer to the
MSP430 User’s Guide [5] for more information about the MSP430 MCU.

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Data rate [baud]
9 600
38 400
56 700
115 200
Table 5 –Data rates supported by the USB MCU in UART Mode
RTS
CTS
TXD
RXD
CC2511 MSP430
RTS
CTS
TXD
RXD
USB_UART_RXD
USB_UART_TXD
USB_UART_CTS
USB_UART_RTS
MSP430 I/O
breakout P4.4
P2.7
P5.6
P5.7
Figure 5 –UART lines connected between the USB MCU and the onboard MSP430 MCU.
CTS and RTS lines are dotted to indicate that the USB MCU standard firmware only
implements a two-line UART interface to the MSP430 MCU.
6.1.3 Disabled Mode
Disabled Mode is obtained by setting hardware switch S2 on the EB to “Disable” position (see
Table 4). The position of S1 is disregarded by the USB MCU when S2 is in the “Disable” position.
In Disabled Mode, the USB MCU is in power-down mode and no USB communication is possible
between a PC and the EB. It is however still possible to power the EB via the USB cable, see
section 6.3.2.
NOTE: Figure 5 shows the four hardware connected UART lines the USB MCU and the
MSP430 MCU. The MSP430 does not support hardware flow control (RTS and CTS lines).
Such support must be manually implemented in the MSP430 software. To ease MSP430
application development, the standard USB MCU firmware uses a two-line UART interface to
the MSP430, i.e. hardware flow control is not implemented.

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6.2 MSP430 MCU
The SmartRF TrxEB is equipped with a MSP430F5438A micro controller from Texas Instruments.
Please see the MSP430F5438A product page [6] on the TI website for detailed information about
this controller.
All of the EB’s user interface peripherals are available to the MSP430 (Figure 3 on page 12).
Excluding the EM, the list of available peripherals consists of
- LCD
- 5x Buttons
- 4x LEDs
- Ambient Light Sensor
- Accelerometer
- SPI Flash.
The recommended operating condition for the MSP430 is a supply voltage (VCC) between 1.8 V
and 3.6 V. The min (max) operating temperature is -40 (+85) ˚C.
6.3 Power Sources
There are four possible solutions for applying power to the SmartRF TrxEB; batteries, USB bus,
external power supply and MSP-FET. The power source can be selected using the power source
selection jumpers on header P17 (Figure 6). The main power supply switch (S5) turns off all
power sources.
Figure 6 –Main power selection header (P17) and power switch (P5)
WARNING! Do not use multiple power sources to power the SmartRF TrxEB at the same
time. Doing so may lead to excessive currents, causing onboard components to break.
WARNING! When using the SmartRF TrxEB with a MSP430 debugger (e.g. MSP-
FET430UIF), while powering the EB with a different power source (batteries, USB or external
power supply), a jumper should short circuit pin 9-10 of header P17 (“LCL”). This will prevent
the MSP-FET from supplying power to the EB.
NOTE: The onboard MSP430 MCU is held in reset by the USB MCU in SmartRF Mode. In
order to use the MSP430, make sure the USB MCU is set to Disabled Mode or UART Mode.
See section 6.1 for details.

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6.3.1 Battery Power
The SmartRF TrxEB includes a battery holder for two 1.5 V AA batteries on the reverse side of
the PCB. Normal AA batteries can be used and the onboard regulator supplies 3.3 V to the board.
The power source selection jumpers should short circuit pin 1-2 (“BATT”) and 9-10 (“LCL”) of
header P17, see Figure 7.
Figure 7 –P17 jumper settings to power TrxEB using batteries
The maximum current consumption is limited by the regulator to 800 mA.
6.3.2 USB Power
When the SmartRF TrxEB is connected to a PC via a USB cable, it can draw power from the USB
bus. The onboard voltage regulator supplies approximately 3.3 V to the board. The power source
selection jumpers should short circuit pin 3-4 (“USB”) and 9-10 (“LCL”) of header P17 (Figure 8).
Figure 8 –P17 jumper settings to power TrxEB via the USB cable
The maximum current consumption is limited by the regulator to 1500 mA
1
.
1
Note that most USB power sources are limited to 500 mA.

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6.3.3 External Power Supply
The SmartRF TrxEB has a connector for powering the board using an external power supply. The
power source selection jumpers should short circuit pin 5-6 (“EXT”) and 9-10 (“LCL”) of header
P16 as shown in Figure 9.
Figure 9 –P17 jumper settings to power TrxEB using external power supply
The external supply’s ground should be connected to pin 2 of P201. Apply a voltage in the range
from 3.0 V to 3.3 V to pin 1 (see Figure 10). Pin 1 and pin 2 of P201 are marked “Vext” and
“GND”, respectively, on SmartRF TrxEB revision 1.5.0.
Figure 10 –Powering TrxEB via the external power supply connector (P201)
WARNING! When using an external power source, all onboard voltage regulators are
bypassed. There is a risk of damaging the onboard components if the applied voltage on the
external power connector/header is lower than -0.3 V or higher than 3.6 V (combined
absolute maximum ratings for onboard components. See section 5.1 for further information.
Pin 1: Vext
Pin 2: GND

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6.3.4 MSP-FET Power
The SmartRF TrxEB can be powered via a MSP430 debugger such as MSP-FET430UIF. The
power source selection jumpers should in that case short circuit pin 7-8 of header P17 (Figure
11). Note that the MSP-FET will not power the EB if pin 9-10 of header P17 (“LCL”) is short
circuited.
Figure 11 –P17 jumper settings to power EB using a MSP-FET
6.4 LCD
The SmartRF TrxEB comes with a 128x64 pixels display from Electronic Assembly (DOGM128E-
6) [7]. The LCD display is available to the onboard MSP430 via an SPI interface, enabling
software development of user interfaces and demo use. The LCD display shares SPI interface
with the serial flash device (section 6.7).
The recommended operating condition for the LCD display is a supply voltage between 3.0 V and
3.3 V. The min (max) operating temperature is -20 (+70) ˚C.
6.5 Accelerometer
The SmartRF TrxEB is equipped with a digital accelerometer from VTI Technologies (CMA3000-
D01) [8]. The accelerometer is available to the onboard MSP430 MCU via an SPI interface and
has a dedicated interrupt line to the MCU. The onboard accelerometer is suitable for application
development, prototyping and demo use. See sections 9.2.2 and 10.2.2 for details on
accelerometer axis orientation for EB revision 1.3.0 and 1.5.0, respectively.
The recommended operating condition for the accelerometer is a supply voltage between 1.7 V
and 3.6 V. The min (max) operating temperature is -40 (+85) ˚C.
6.6 Ambient Light Sensor
The SmartRF TrxEB has an analog SFH 5711 ambient light sensor from Osram [9] that is
available to the onboard MSP430, enabling quick application development for demo use and
prototyping. The light sensor is placed outside the bottom right corner of the LCD display.
The recommended operating condition for the ambient light sensor is a supply voltage between
2.3 V and 5.5 V. The min (max) operating temperature is -40 (+85) ˚C.
6.7 Serial Flash
SmartRF TrxEB has a M25PE20 flash device –a paged 256 KB serial flash memory from Micron
[10]. The device gives the MSP430 access to extra flash, enabling over-the-air upgrades and
more. The serial device shares SPI bus with the LCD display (section 6.4).
The recommended operating condition for the serial flash device is a supply voltage between 2.7
V and 3.6 V. The min (max) operating temperature is -40 (+85) ˚C.

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6.8 Buttons
There are 7 buttons on the SmartRF TrxEB. Status of BTN_LEFT, BTN_RIGHT, BTN_UP,
BTN_DOWN and BTN_SELECT can be read by the onboard MSP430. These buttons are
intended for user interfacing and development of demo applications.
The RESET MCU button resets the MSP430 MCU by pulling its reset line low (MCU_RESET_N).
The RESET USB button similarly resets the USB controller (pulling USB_RESET_N low). Note
that the standard firmware on the USB controller will reset the EM and MSP430 during startup, so
pushing the RESET USB button also resets the controller on the EM board and the MSP430.
6.9 LEDs
6.9.1 General Purpose LEDs
The four LEDs D3, D4, D5, D7 can be controlled from the onboard MSP430 and are suitable for
demo use and debugging. The LEDs are active low.
6.9.2 USB LED
LED D6 (USB LED) is controlled by the USB controller and is used to indicate the status of the
EB. The USB LED has several states, listed in Table 6.
USB LED state
Description
OFF
Power is turned off, the USB controller is in Disabled
Mode or the software on the USB controller is corrupt.
ON
SmartRF Mode: The standard firmware is running and
a RF-IC has been detected.
UART Mode: The standard firmware is running. The
USB LED is quickly toggled OFF/ON when UART traffic.
This is typically seen as slight variations in emitted
intensity.
BLINKING (100 ms ON –900 ms OFF)
SmartRF Mode: No RF-IC is detected.
BLINKING (1 Hz)
The USB MCU has entered the boot recovery mode.
See chapter 11 for further details.
BLINKING (10 Hz)
The bootloader on the USB MCU could not find a valid
application to boot. Basic USB services are available
and both SmartRF Studio and SmartRF Flash
Programmer can be used to program an application to
the USB controller’s flash. See chapter 11 for further
details.
Table 6 –USB LED state descriptions