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EFR32FG1 2400/868 MHz 13 dBm Dual Band (SLWRB4250B)

Overview

The EFR32FG1 Flex Gecko 2.4 GHz and 868 MHz Radio Board is delivered as part of SLWSTK6061B Proprietary Wireless Starter Kit. It contains a EFR32FG1 Wireless SoC built on an ARM Cortex®-M4F processor with excellent low power capabilities.

SLWRB4250B (image courtesy of Silicon Labs)

The BRD4250B a.k.a. SLWRB4250B radio board plugs into the Wireless Starter Kit Mainboard BRD4001A and is supported as one of Radio Boards.

Hardware

• EFR32FG1P133F256GM48 Flex Gecko SoC

• CPU core: ARM Cortex®-M4 with FPU

• Flash memory: 256 kB

• RAM: 32 kB

• Transmit power: up to +13 dBm

• Operation frequency: 2.4 GHz, 868 MHz

• 8Mbit SPI NOR Flash

• Crystals for LFXO (32.768 kHz) and HFXO (38.4 MHz).

For more information about the EFR32FG1 SoC and BRD4250B board, refer to these documents:

• EFR32FG1 Website

• EFR32FG1 Datasheet

• EFR32xG1 Reference Manual

• SLWSTK6061B Proprietary Wireless Starter Kit

• BRD4250B User Guide

• BRD4250B Reference Manual

• EFR32FG1-BRD4250B Schematics

Supported Features

The board configuration supports the following hardware features:

Interface	Controller	Driver/Component
MPU	on-chip	memory protection unit
NVIC	on-chip	nested vector interrupt controller
SYSTICK	on-chip	systick
COUNTER	on-chip	rtcc
FLASH	on-chip	flash memory
GPIO	on-chip	gpio
UART	on-chip	serial port-polling; serial port-interrupt
SPI(M)	on-chip	spi port-polling
WATCHDOG	on-chip	watchdog

The default configuration can be found in boards/silabs/radio_boards/slwrb4250b/slwrb4250b_defconfig

Connections and IOs

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

Pin	Function	Usage
PF4	GPIO	LED0
PF5	GPIO	LED1
PF6	GPIO	Push Button PB0
PF7	GPIO	Push Button PB1
PA5	GPIO	Board Controller Enable VCOM_ENABLE
PA0	USART0_TX	UART Console VCOM_TX US0_TX #0
PA1	USART0_RX	UART Console VCOM_RX US0_RX #0
PC6	SPI_MOSI	Flash MOSI US1_TX #11
PC7	SPI_MISO	Flash MISO US1_RX #11
PC8	SPI_SCLK	Flash SCLK US1_CLK #11
PA4	SPI_CS	Flash Chip Select (GPIO)

System Clock

The EFR32FG1P SoC is configured to use the 38.4 MHz external oscillator on the board.

Serial Port

The EFR32FG1P SoC has two USARTs and one Low Energy UARTs (LEUART). USART0 is connected to the board controller and is used for the console.

Programming and Debugging

Flashing

Connect the BRD4001A board with a mounted BRD4250B 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 slwrb4250b 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! slwrb4250b