Silicon Laboratories EFR32xG21 Wireless Gecko User manual

UG429: EFR32xG21 2.4 GHz 10 dBm
Wireless Starter Kit User's Guide
A Wireless Starter Kit with the BRD4181B Radio Board is an ex-
cellent starting point to get familiar with the EFR32™ Wireless
Gecko Wireless System-on-Chip. It also provides all necessary
tools for developing a Silicon Labs wireless application.
BRD4181B is a plug-in board for the Wireless Starter Kit Mainboard. It is a complete ref-
erence design for the EFR32xG21 Wireless SoC, with matching network and a PCB an-
tenna for 10 dBm output power in the 2.4 GHz 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 of 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 BRD4181B Radio Board together with a Wire-
less Starter Kit Mainboard.
BRD4181B RADIO BOARD FEATURES
• EFR32xG21 Wireless Gecko Wireless
SoC with 1024 kB Flash and 96 kB RAM
(EFR32MG21A010F1024IM32).
• Inverted-F PCB antenna (2.4 GHz band)
• 2x user color LEDs (red and green)
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
• Low power 128x128 pixel Memory LCD-
TFT
• 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
• SLWSTK6006A
• SLWSTK6023A
• SLWRB4181B
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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 ...........................14
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 Virtual COM Port .............................18
5.3.1 Host Interfaces ............................19
5.3.2 Serial Configuration ...........................19
5.3.3 Hardware Handshake ..........................20
6. Board Controller ............................. 21
6.1 Admin Console ..............................21
6.1.1 Connecting ..............................21
6.1.2 Built-in Help .............................21
6.1.3 Command Examples ..........................22
6.2 Virtual UART ..............................22
6.2.1 Target to Host .............................22
6.2.2 Host to Target .............................22
6.2.3 Limitations ..............................22
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6.2.4 Troubleshooting ............................23
7. Advanced Energy Monitor ......................... 24
7.1 Introduction ...............................24
7.2 Theory of Operation ............................24
7.3 AEM Accuracy and Performance ........................25
7.4 Usage .................................25
8. On-Board Debugger ............................ 26
8.1 Host Interfaces ..............................26
8.1.1 USB Interface .............................26
8.1.2 Ethernet Interface ...........................26
8.1.3 Serial Number Identification ........................26
8.2 Debug Modes ..............................27
8.3 Debugging During Battery Operation ......................28
9. Kit Configuration and Upgrades ....................... 29
9.1 Firmware Upgrades ............................29
10. Schematics, Assembly Drawings, and BOM .................. 30
11. Kit Revision History ........................... 31
11.1 SLWRB4181B Revision History ........................31
11.2 SLWSTK6023A Revision History .......................31
11.3 SLWSTK6006A Revision History .......................31
12. Document Revision History ........................ 32
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1. Introduction
The EFR32xG21 Wireless Gecko Wireless SoC is featured on a radio board that plugs directly into a Wireless Starter Kit (WSTK) Main-
board. The mainboard features several tools for easy evaluation and development of wireless applications. An on-board J-Link debug-
ger 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 ra-
dio board.
To further enhance its usability, the mainboard contains sensors and peripherals that demonstrate some of the many capabilities of the
EFR32xG21. A 20-pin expansion header (EXP header) is also provided that allows connection of expansion boards (EXP boards) to
the kit.
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 EFR32xG21 2.4 GHz 10 dBm Radio Board (BRD4181B) is com-
bined with a Wireless STK Mainboard. The combination of these two boards is hereby referred to as a Wireless Starter Kit (Wireless
STK).
1.2 Ordering Information
BRD4181B can be obtained as part of SLWSTK6006A EFR32xG21 2.4 GHz Mesh Networking Starter Kit, SLWSTK6023A EFR32xG21
Bluetooth Starter Kit, or as a separate radio board, SLWRB4181B.
Table 1.1. Ordering Information
Part Number Description Contents
SLWSTK6006A EFR32xG21 2.4 GHz Mesh Networking Starter Kit 3x BRD4001A Wireless Starter Kit Mainboard
3x BRD4180B EFR32xG21 2.4 GHz 20 dBm Radio Board
3x BRD4181B EFR32xG21 2.4 GHz 10 dBm Radio Board
3x AA battery holders
3x USB Type A to Mini-B cables
1x 10-pin 1.27mm IDC debug cable
1x BRD8010A Debug Adapter Board
SLWSTK6023A EFR32xG21 Bluetooth Starter Kit 1x BRD4001A Wireless Starter Kit Mainboard
1x BRD4181B EFR32xG21 2.4 GHz 10 dBm Radio Board
1x USB Type A to Mini-B cables
SLWRB4181B EFR32xG21 2.4 GHz 10 dBm Radio Board 1x BRD4181B EFR32xG21 2.4 GHz 10 dBm Radio Board
1.3 Getting Started
Detailed instructions for how to get started can be found on the Silicon Labs web pages:
silabs.com/start-efr32xg21
UG429: EFR32xG21 2.4 GHz 10 dBm Wireless Starter Kit User's Guide
Introduction
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2. Hardware Overview
2.1 Hardware Layout
The layout of the EFR32xG21 2.4 GHz 10 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
(Not available to BRD4181B)
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
UG429: EFR32xG21 2.4 GHz 10 dBm Wireless Starter Kit User's Guide
Hardware Overview
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2.2 Block Diagram
An overview of the EFR32xG21 2.4 GHz 10 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
2.4 GHz RF
Inverted-F
PCB Antenna
EFR32xG21
Wireless SoC
ETM Trace
128 x 128 pixel
Memory LCD
GPIO
GPIO
GPIO
EXP
Header
User Buttons
& LEDs
R/G LED
Figure 2.2. Kit Block Diagram
UG429: EFR32xG21 2.4 GHz 10 dBm Wireless Starter Kit 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
Note: 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.
UG429: EFR32xG21 2.4 GHz 10 dBm Wireless Starter Kit 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
map to the pin numbers printed on the breakout pads. To see the available functions on each, refer to the data sheet for
EFR32MG21A010F1024IM32.
GND
VMCU
P23 / NC
P21 / NC
P19 / NC
P17 / NC
GND
P15 / NC
P13 / NC
P11 / PA06 / EXP14 / VCOM_RX
P9 / PA05 / EXP12 / VCOM_TX
P7 / PC03 / EXP10 / DISP_SCS
P5 / PC02 / EXP8 / DISP_SCLK
P3 / PC01 / EXP6 / VCOM_RTS
P1 / PC00 / EXP4 / DISP_MOSI
VRF
GND
VMCU
VCOM_CTS / PA04 / P22
DBG_TDO_SWO / PA03 / P20
DBG_TMS_SWDIO / PA02 / P18
DBG_TCK_SWCLK / PA01 / P16
GND
DISP_EXTCOMIN / PA00 / P14
NC / P12
UIF_LED1 / EXP13 / PD03 / P10
UIF_LED0 / EXP11 / PD02 / P8
UIF_BUTTON1 / EXP9 / PB01 / P6
UIF_BUTTON0 / EXP7 / PB00 / P4
NC / P2
NC / P0
VRF
J101
GNDGND
5V5V
NCNC
P45 / NCNC / P44
P43 / NCTRACED0 / PA03 / P42
P41 / NCNC / P40
3V33V3
P39 / NCNC / P38
P37 / NCDISP_EXTCOMIN / PA00 / P36
P35 / NCNC / P34
P33 / NCNC / P32
P31 / PD04 / VCOM_ENABLE / DISP_ENABLENC / P30
P29 / NCNC / P28
P27 / PC05 / PTI_SYNCNC / P26
P25 / PC04 / PTI_DATANC / P24
GNDGND
J102
Figure 3.2. Breakout Pad Pin Mapping
UG429: EFR32xG21 2.4 GHz 10 dBm Wireless Starter Kit 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 Wireless
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 / PC00
SPI_MISO / PC01
SPI_CLK / PC02
SPI_CS / PC03
UART_TX / PA05
UART_RX / PA06
NC
5V
3V3
GND
NC
NC
PB00 / GPIO
PB01 / GPIO
PD02 / GPIO
PD03 / GPIO
NC
BOARD_ID_SDA
BOARD_ID_SCL
Reserved (Board Identification)
EFR32 I/O Pin
Figure 3.3. EXP Header
UG429: EFR32xG21 2.4 GHz 10 dBm Wireless Starter Kit User's Guide
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 EXP 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 NC I2C_SDA
14 PA06 UART_RX VCOM_RX USART0_RX
12 PA05 UART_TX VCOM_TX USART0_TX
10 PC03 SPI_CS DISP_SCS USART0_CS
8 PC02 SPI_SCLK DISP_SCLK USART0_SCLK
6 PC01 SPI_MISO VCOM_RTS USART0_RTS
4 PC00 SPI_MOSI DISP_MOSI USART0_MOSI
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 NC I2C_SCL
13 PD03 GPIO UIF_LED1
11 PD02 GPIO UIF_LED0
9 PB01 GPIO UIF_BUTTON1
7 PB00 GPIO UIF_BUTTON0
5 NC GPIO
3 NC GPIO
1 GND Ground
UG429: EFR32xG21 2.4 GHz 10 dBm Wireless Starter Kit User's Guide
Connectors
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