EFR32xG21 2.4 GHz 20 dBm (SLWRB4180A)

Overview

The EFR32MG21 Mighty Gecko Radio Board is one of the two radio boards delivered with EFR32-SLWSTK6006A Website. It contains a Wireless System-On-Chip from the EFR32MG21 family built on an ARM Cortex®-M33F processor with excellent low power capabilities.

The BRD4180A a.k.a. SLWRB4180A radio board plugs into the Wireless Starter Kit Mainboard BRD4001A and is supported as one of Radio Boards.

Hardware

EFR32MG21A020F1024IM32 Mighty Gecko SoC
CPU core: ARM Cortex®-M33 with FPU
Flash memory: 1024 kB
RAM: 96 kB
Transmit power: up to +20 dBm
Operation frequency: 2.4 GHz
Crystals for LFXO (32.768 kHz) and HFXO (38.4 MHz).

For more information about the EFR32MG21 SoC and BRD4180A board, refer to these documents:

Supported Features

The slwrb4180a board supports the hardware features listed below.

on-chip / on-board: Feature integrated in the SoC / present on the board.
2 / 2: Number of instances that are enabled / disabled.
Click on the label to see the first instance of this feature in the board/SoC DTS files.
vnd,foo: Compatible string for the Devicetree binding matching the feature.
Click on the link to view the binding documentation.

`slwrb4180a/efr32mg21a020f1024im32` target

Type	Location	Description	Compatible
CPU	on-chip	ARM Cortex-M33F CPU1	`arm,cortex-m33f`
Clock control	on-chip	Silicon Labs Series 2+ clock control node1	`silabs,series-clock`
	on-chip	Generic fixed-rate clock provider3	`fixed-clock`
	on-chip	Generic fixed-rate clock provider1	`silabs,hfxo`
	on-chip	Silicon Labs LFXO peripheral (low-frequency crystal oscillator)1	`silabs,series2-lfxo`
	on-chip	Silicon Labs HFRCODPLL peripheral (high-frequency RC oscillator with digital phase-locked loop)1	`silabs,series2-hfrcodpll`
	on-chip	Silicon Labs HFRCOEM23 peripheral (high-frequency RC oscillator with energy mode 2 and 3 capability)1	`silabs,series2-hfrcoem23`
	on-chip	Silicon Labs LFRCO peripheral (low-frequency RC oscillator)1	`silabs,series2-lfrco`
	on-chip	Generic fixed factor clock provider13	`fixed-factor-clock`
Comparator	on-chip	Silabs ACMP (Analog Comparator)1	`silabs,acmp`
Cryptographic accelerator	on-chip	Silicon Labs Secure Element mailbox node1	`silabs,gecko-semailbox`
DMA	on-chip	Silabs LDMA controller1	`silabs,ldma`
Flash controller	on-chip	Silicon Labs Series 2 flash controller1	`silabs,series2-flash-controller`
GPIO & Headers	on-chip	SiLabs Gecko GPIO1	`silabs,gecko-gpio`
GPIO & Headers	on-chip	SiLabs Gecko GPIO Port4	`silabs,gecko-gpio-port`
I2C	on-chip	Silabs Gecko I2C2	`silabs,gecko-i2c`
Input	on-board	Group of GPIO-bound input keys1	`gpio-keys`
Interrupt controller	on-chip	ARMv8-M NVIC (Nested Vectored Interrupt Controller)1	`arm,v8m-nvic`
LED	on-board	Group of GPIO-controlled LEDs1	`gpio-leds`
MMU / MPU	on-chip	ARMv8-M MPU (Memory Protection Unit)1	`arm,armv8m-mpu`
MTD	on-chip	Flash node1	`soc-nv-flash`
MTD	on-board	Fixed partitions of a flash (or other non-volatile storage) memory1	`fixed-partitions`
Networking	on-chip	Silicon Labs Series 2 radio interface1	`silabs,series2-radio`
Pin control	on-chip	The Silabs pin controller is a singleton node responsible for controlling pin function selection and pin properties1	`silabs,dbus-pinctrl`
RTC	on-chip	Silabs Gecko Sleep Timer (Real-Time Counter)1	`silabs,gecko-stimer`
Serial controller	on-chip	Silabs USART UART1 2	`silabs,usart-uart`
SRAM	on-chip	Generic on-chip SRAM description1	`mmio-sram`
Timer	on-chip	ARMv8-M System Tick1	`arm,armv8m-systick`
Watchdog	on-chip	Silicon Labs Gecko Family Watchdog driver1 1	`silabs,gecko-wdog`

Connections and IOs

In the following table, the column Name contains Pin names. For example, PA2 means Pin number 2 on PORTA, as used in the board’s datasheets and manuals.

Name	Function	Usage
PB0	GPIO	LED0
PB1	GPIO	LED1
PD2	GPIO	Push Button PB0
PD3	GPIO	Push Button PB1
PD4	GPIO	Board Controller Enable EFM_BC_EN
PA5	USART1_TX	UART Console EFM_BC_TX US1_TX
PA6	USART1_RX	UART Console EFM_BC_RX US1_RX

The default configuration can be found in boards/silabs/radio_boards/slwrb4180a/slwrb4180a_defconfig

System Clock

The EFR32MG21 SoC is configured to use the 38.4 MHz external oscillator on the board.

Serial Port

The EFR32MG21 SoC has three USARTs. USART0 is connected to the board controller and is used for the console.

Programming and Debugging

Flashing

Connect the BRD4001A board with a mounted BRD4180A radio module to your host computer using the USB port.

Here is an example for the Hello World application.

# From the root of the zephyr repository
west build -b slwrb4180a samples/hello_world
west flash

Open a serial terminal (minicom, putty, etc.) with the following settings:

Speed: 115200
Data: 8 bits
Parity: None
Stop bits: 1

Reset the board and you should see the following message in the terminal:

Hello World! slwrb4180a