Silicon Laboratories BRD4251D User manual

UG185: EFR32FG1 2400/169 MHz
Dual Band Radio Board User's Guide
A Wireless Starter Kit with the BRD4251D Radio Board is an ex-
cellent starting point to get familiar with the EFR32™ Flex Gecko
Wireless System-on-Chip, and it provides all necessary tools for
developing a Silicon Labs wireless application.
BRD4251D is a plug-in board for the Wireless Starter Kit Mainboard. It is a complete ref-
erence design for the EFR32FG1 Wireless SoC, with matching networks for 19.5 dBm
output power, a 2.4 GHz PCB antenna, and an SMA connector for the 169 MHz band.
The Wireless Starter Kit Mainboard contains an on-board J-Link debugger with a Packet
Trace Interface and a Virtual COM port, enabling application development and debug-
ging the attached radio board as well as external hardware. The Mainboard also con-
tains sensors and peripherals for easy demonstration of some of the EFR32's many ca-
pabilities.
This document describes how to use the BRD4251D Radio Board together with a Wire-
less Starter Kit Mainboard.
BRD4251D RADIO BOARD FEATURES
• EFR32FG1 Flex Gecko Wireless SoC with
256 kB Flash, and 32 kB RAM
(EFR32FG1P133F256GM48)
• Dual band integrated radio transceiver
• 19.5 dBm output power
• Inverted-F PCB antenna (2.4 GHz)
• SMA antenna connector (169 MHz)
• 8 Mbit low-power serial flash for over-the-
air upgrades.
WIRELESS STK MAINBOARD FEATURES
• Advanced Energy Monitor
• Packet Trace Interface
• Virtual COM Port
• SEGGER J-Link on-board debugger
• External device debugging
• Ethernet and USB connectivity
• Silicon Labs Si7021 Relative Humidity and
Temperature sensor
• Low Power 128x128 pixel Memory LCD
• User LEDs / Pushbuttons
• 20-pin 2.54 mm EXP header
• Breakout pads for Wireless SoC I/O
• CR2032 coin cell battery support
SOFTWARE SUPPORT
• Simplicity Studio™
• Energy Profiler
• Network Analyzer
ORDERING INFORMATION
• SLWRB4251D
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Table of Contents
1. Introduction ................................4
1.1 Radio Boards ..............................4
1.2 Ordering Information ...........................4
1.3 Getting Started .............................4
2. Hardware Overview .............................5
2.1 Hardware Layout .............................5
2.2 Block Diagram..............................6
3. Connectors ................................7
3.1 J-Link USB Connector ...........................7
3.2 Ethernet Connector ............................7
3.3 Breakout Pads .............................8
3.4 EXP Header ..............................9
3.4.1 EXP Header Pinout ..........................10
3.5 Debug Connector.............................11
3.6 Simplicity Connector............................12
3.7 Debug Adapter .............................13
4. Power Supply and Reset .......................... 14
4.1 Radio Board Power Selection ........................14
4.2 Board Controller Power...........................15
4.3 EFR32 Reset ..............................15
4.4 Battery Holder ..............................15
5. Peripherals ............................... 16
5.1 Push Buttons and LEDs ..........................16
5.2 Memory LCD-TFT Display..........................17
5.3 Serial Flash ..............................18
5.4 Si7021 Relative Humidity and Temperature Sensor .................19
5.5 Virtual COM Port .............................20
5.5.1 Host Interfaces ...........................21
5.5.2 Serial Configuration ..........................21
5.5.3 Hardware Handshake .........................22
6. Board Controller ............................. 23
6.1 Admin Console .............................23
6.1.1 Connecting .............................23
6.1.2 Built-in Help ............................23
6.1.3 Command Examples .........................24
6.2 Virtual UART ..............................24
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7. Advanced Energy Monitor ......................... 25
7.1 Introduction...............................25
7.2 Theory of Operation ............................25
7.3 AEM Accuracy and Performance .......................26
7.4 Usage ................................26
8. On-Board Debugger ............................ 27
8.1 Host Interfaces .............................27
8.1.1 USB Interface ............................27
8.1.2 Ethernet Interface ..........................27
8.1.3 Serial Number Identification .......................27
8.2 Debug Modes ..............................28
8.3 Debugging During Battery Operation ......................29
9. Kit Configuration and Upgrades ....................... 30
9.1 Firmware Upgrades ............................30
10. Schematics, Assembly Drawings, and BOM .................. 31
11. Kit Revision History ........................... 32
11.1 SLWSTK6065A Revision history .......................32
11.2 SLWRB4251D Revision history........................32
12. Document Revision History ........................ 33
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1. Introduction
The EFR32FG1 Flex Gecko Wireless SoC itself is featured on a Radio Board that forms a complete reference design, including the RF
section and other components.
The Radio Board plugs directly into a Wireless Starter Kit Mainboard. The Mainboard features several tools for easy evaluation and
development of wireless applications. An on-board J-Link debugger enables programming and debugging on the target device over
USB or Ethernet. The Advanced Energy Monitor (AEM) offers real-time current and voltage monitoring. A virtual COM port interface
(VCOM) provides an easy-to-use serial port connection over USB or Ethernet. The Packet Trace Interface (PTI) offers invaluable debug
information about transmitted and received packets in wireless links.
All debug functionality, including AEM, VCOM and PTI, can also be used towards external target hardware instead of the attached radio
board.
To further enhance its usability, the Mainboard contains sensors and peripherals demonstrating some of the many capabilities of the
EFR32FG1.
1.1 Radio Boards
A Wireless Starter Kit consists of one or more mainboards and radio boards that plug into the mainboard. Different radio boards are
available, each featuring different Silicon Labs devices with different operating frequency bands.
Since the mainboard is designed to work with all different radio boards, the actual pin mapping from a device pin to a mainboard feature
is done on the radio board. This means that each radio board has its own pin mapping to the Wireless Starter Kit features such as
buttons, LEDs, the display, the EXP header and the breakout pads. Because this pin mapping is different for every radio board, it is
important that the correct document be consulted which shows the kit features in context of the radio board plugged in.
This document explains how to use the Wireless Starter Kit when the EFR32FG1 2400/169 MHz 19.5 dBm Radio Board (BRD4251D) is
combined with a Wireless STK Mainboard. The combination of these two boards is hereby referred to as a Wireless Starter Kit (Wire-
less STK).
1.2 Ordering Information
BRD4251D can be obtained as a separate radio board, SLWRB4251D.
Table 1.1. Ordering Information
Part Number Description Contents Notes
SLWRB4251D EFR32FG1 2400/169 MHz
19.5 dBm Dual Band Radio
Board
1x BRD4251D EFR32FG1 2400/169 MHz 19.5 dBm Dual Band
Radio Board
1x 169 MHz dipole antenna (Laird EXH170SM)
SLWSTK6065A EFR32FG1 2400/169 MHz
Wireless Starter Kit
2x BRD4001A Wireless Starter Kit Mainboard
2x BRD4251D EFR32FG1 2400/169 MHz 19.5 dBm Dual Band
Radio Board
2x 169 MHz dipole antenna (Laird EXH170SM)
2x 2xAA Battery Holder
2x USB Type A to Mini-B cable
Discontinued
1.3 Getting Started
Detailed instructions for how to get started can be found on the Silicon Labs web pages:
http://www.silabs.com/start-efr32fg
UG185: EFR32FG1 2400/169 MHz Dual Band Radio Board User's Guide
Introduction
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2. Hardware Overview
2.1 Hardware Layout
The layout of the EFR32FG1 2400/169 MHz 19.5 dBm Wireless Starter Kit is shown in the figure below.
On-board USB and
Ethernet J-Link
Debugger
Radio Board Breakout Pads Plug-in Radio Board
Si7021 Humidity and
Temperature Sensor
EXP-header for
expansion boards
Serial-port, packet trace and Advanced
Energy Monitoring header
ARM Coresight 19-pin
trace/debug header
Ultra-low power 128x128
pixel memory LCD,
buttons and LEDs
Battery or
USB power
USB-serial-port
Packet-trace
Advanced Energy
Monitoring
Figure 2.1. Kit Hardware Layout
UG185: EFR32FG1 2400/169 MHz Dual Band Radio Board User's Guide
Hardware Overview
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2.2 Block Diagram
An overview of the EFR32FG1 2400/169 MHz 19.5 dBm Wireless Starter Kit is shown in the figure below.
Debug
USB Mini-B
Connector
UART
RJ-45 Ethernet
Connector
Packet Trace
AEM
Multiplexer
Debug
UART
ETM Trace
Packet Trace
AEM
Debug
UART
Packet Trace
AEM
Simplicity
Connector
Debug
Connector
Board
Controller
OUT
IN
MCU
SMA
Connector
EFR32FG1
Wireless SoC
ETM Trace
128 x 128 pixel
Memory LCD
I2C Si7021
Temperature
& Humidity
Sensor
SPI 8 Mbit
MX25R
Serial Flash
GPIO
EXP
Header
User Buttons
& LEDs
GPIO
SMA
Connector
SMA
Connector
169 MHz RF
2.4 GHz RF
Inverted-F
PCB Antenna
Figure 2.2. Kit Block Diagram
UG185: EFR32FG1 2400/169 MHz Dual Band Radio Board User's Guide
Hardware Overview
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3. Connectors
This chapter gives you an overview of the Wireless STK Mainboard connectivity. The placement of the connectors are shown in the
figure below.
Simplicity
Connector
Debug
Connector
GND
GND
5V
5V
P25
P24
P27
P26
P29
P28
P31
P30
P33
P32
P35
P34
P37
P36
P39
P38
P41
P40
P43
P42
P45
P44
GND
GND
NC
NC
Radio Board
Connectors
EXP Header
GND
GND
VMCU
VMCU
P1
P0
P3
P2
P5
P4
P7
P6
P9
P8
P11
P10
P13
P12
P15
P14
P17
P16
P19
P18
P21
P20
GND
GND
P23
P22
VRF
VRF
3V3
3V3
Ethernet
Connector
J-Link USB
Connector
Figure 3.1. Mainboard Connector Layout
3.1 J-Link USB Connector
The J-Link USB connector is situated on the left side of the Wireless Starter Kit Mainboard. Most of the kit's development features are
supported through this USB interface when connected to a host computer, including:
• Debugging and programming of the target device using the on-board J-Link debugger
• Communication with the target device over the virtual COM port using USB-CDC
• Accurate current profiling using the AEM
In addition to providing access to development features of the kit, this USB connector is also the main power source for the kit. USB 5V
from this connector powers the board controller and the AEM. It is recommended that the USB host be able to supply at least 500 mA
to this connector, although the actual current required will vary depending on the application.
3.2 Ethernet Connector
The Ethernet connector provides access to all of the Wireless Starter Kit's development features over TCP/IP. The Ethernet interface
provides some additional development features to the user. Supported features include:
• Debugging and programming of the target device using the on-board J-Link debugger
• Communication with the target device over the virtual COM port using TCP/IP socket 4901
• "VUART" communication with the target device over the debug SWD/SWO interface using TCP/IP socket 4900
• Accurate current profiling using the AEM
• Real-time radio packet and network analysis using the Packet Trace Interface
• Access to advanced configuration options using the admin console over TCP/IP socket 4902
Please note that the Wireless Starter Kit cannot be powered using the Ethernet connector, so in order to use this interface, the USB
connector must be used to provide power to the board.
UG185: EFR32FG1 2400/169 MHz Dual Band Radio Board User's Guide
Connectors
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3.3 Breakout Pads
Most pins of the EFR32 are routed from the radio board to breakout pads at the top and bottom edges of the Wireless STK Mainboard.
A 2.54 mm pitch pin header can be soldered on for easy access to the pins. The figure below shows you how the pins of the EFR32
maps to the pin numbers printed on the breakout pads. To see the available functions on each, refer to the data sheet for
EFR32FG1P133F256GM48.
GND
VMCU
P23 / NC
P21 / NC
P19 / NC
P17 / NC
GND
P15 / NC
P13 / PC11 / EXP16 / I2C_SDA
P11 / PA1 / EXP14 / VCOM_RX
P9 / PA0 / EXP12 / VCOM_TX
P7 / PC9 / EXP10
P5 / PC8 / EXP8 / FLASH_SCLK / DISP_SCLK
P3 / PC7 / EXP6 / FLASH_MISO
P1 / PC6 / EXP4 / FLASH_MOSI / DISP_SI
VRF
GND
VMCU
PTI_SYNC / PB13 / P22
PTI_DATA / PB12 / P20
PTI_CLK / PB11 / P18
VCOM_ENABLE / PA5 / P16
GND
FLASH_SCS / PA4 / P14
I2C_SCL / EXP15 / PC10 / P12
DBG_TDI / EXP13 / PF3 / P10
LED0 / EXP11 / PF4 / P8
BTN1 / EXP9 / PF7 / P6
BTN0 / EXP7 / PF6 / P4
VCOM_RTS / EXP5 / PA3 / P2
VCOM_CTS / EXP3 / PA2 / P0
VRF
J101
GNDGND
5V5V
NCNC
P45 / NCNC / P44
P43 / NCNC / P42
P41 / NCNC / P40
3V33V3
P39 / NCNC / P38
P37 / PD15 / DISP_ENABLE / SENSOR_ENABLENC / P36
P35 / PD15 / DISP_ENABLE / SENSOR_ENABLENC / P34
P33 / PD14 / DISP_SCSLED1 / PF5 / P32
P31 / PD13 / DISP_EXTCOMINNC / P30
P29 / NCDBG_TDO_SWO / PF2 / P28
P27 / NCDBG_TMS_SWDIO / PF1 / P26
P25 / NCDBG_TCK_SWCLK / PF0 / P24
GNDGND
J102
Figure 3.2. Breakout Pad Pin Mapping
UG185: EFR32FG1 2400/169 MHz Dual Band Radio Board User's Guide
Connectors
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3.4 EXP Header
The EXP header is an angled 20-pin expansion header provided to allow connection of peripherals or plugin boards to the kit. It is loca-
ted on the right-hand side of the mainboard and it contains a number of I/O pins that can be used with most of the EFR32 Flex Gecko's
features. Additionally, the VMCU, 3V3, and 5V power rails are also exported.
The connector follows a standard which ensures that commonly used peripherals such as an SPI, a UART, and an I2C bus are availa-
ble on fixed locations in the connector. The rest of the pins are used for general purpose IO. This allows the definition of expansion
boards (EXP boards) that can plug into a number of different Silicon Labs Starter Kits.
The figure below shows the pin assignment of the EXP header. Because of limitations in the number of available GPIO pins, some of
the EXP header pins are shared with kit features.
12
4
8
6
10
3
5
9
7
12
13
14
11
1516
17
18
20 19
VMCU
SPI_MOSI / PC6
SPI_MISO / PC7
SPI_CLK / PC8
SPI_CS / PC9
UART_TX / PA0
UART_RX / PA1
I2C_SDA / PC11
5V
3V3
GND
PA2 / GPIO
PA3 / GPIO
PF6 / GPIO
PF7 / GPIO
PF4 / GPIO
PF3 / GPIO
PC10 / I2C_SCL
BOARD_ID_SDA
BOARD_ID_SCL
Reserved (Board Identification)
EFR32 I/O Pin
Figure 3.3. EXP Header
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Connectors
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3.4.1 EXP Header Pinout
The pin-routing on the EFR32 is very flexible, so most peripherals can be routed to any pin. However, many pins are shared between
the EXP header and other functions on the Wireless STK Mainboard. The table below includes an overview of the mainboard features
that share pins with the Expansion Header.
Table 3.1. EXP Header Pinout
Pin Connection EXP Header Function Shared Feature Peripheral Mapping
20 3V3 Board controller supply
18 5V Board USB voltage
16 PC11 I2C_SDA SENSOR_I2C_SDA I2C0_SDA #16
14 PA1 UART_RX VCOM_RX USART0_RX #0
12 PA0 UART_TX VCOM_TX USART0_TX #0
10 PC9 SPI_CS - USART1_CS #11
8 PC8 SPI_SCLK FLASH_SCLK, DISP_SCLK USART1_CLK #11
6 PC7 SPI_MISO FLASH_MISO USART1_RX #11
4 PC6 SPI_MOSI FLASH_MOSI, DISP_SI USART1_TX #11
2 VMCU EFR32 voltage domain, included in AEM measurements.
19 BOARD_ID_SDA Connected to Board Controller for identification of add-on boards.
17 BOARD_ID_SCL Connected to Board Controller for identification of add-on boards.
15 PC10 I2C_SCL SENSOR_I2C_SCL I2C0_SCL #14
13 PF3 GPIO DBG_TDI
11 PF4 GPIO LED0
9 PF7 GPIO BTN1
7 PF6 GPIO BTN0
5 PA3 GPIO VCOM_RTS
3 PA2 GPIO VCOM_CTS
1 GND Ground
Note: Pin PF3 is used for DBG_TDI in JTAG mode only. When the Serial Wire Debugging interface (SWD) is used, PF3 can be used
for other purposes.
UG185: EFR32FG1 2400/169 MHz Dual Band Radio Board User's Guide
Connectors
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