This is the documentation for the latest (master) development branch of Zephyr. If you are looking for the documentation of previous releases, use the drop-down menu on the left and select the desired version.

EFM32 Pearl Gecko Starter Kit

Overview

The EFM32 Pearl Gecko Starter Kit EFM32PG-STK3401A contains an MCU from the EFM32PG family built on an ARM® Cortex®-M4F processor with excellent low power capabilities.

EFM32PG-SLSTK3401A

EFM32PG-SLSTK3401A (image courtesy of Silicon Labs)

Hardware

  • Advanced Energy Monitoring provides real-time information about the energy consumption of an application or prototype design.

  • Ultra low power 128x128 pixel Memory-LCD

  • 2 user buttons, 2 LEDs and 2 capacitive buttons

  • Humidity and temperature sensor

  • On-board Segger J-Link USB debugger

For more information about the EFM32PG SoC and EFM32PG-STK3401A board:

Supported Features

The efm32pg_stk3401a 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

I2C

on-chip

i2c port-polling

WATCHDOG

on-chip

watchdog

The default configuration can be found in the defconfig file:

boards/arm/efm32pg_stk3401a/efm32pg_stk3401a_defconfig

Other hardware features are currently not supported by the port.

Connections and IOs

The EFM32PG1 SoC has five GPIO controllers (PORTA to PORTD and PORTF) and all are enabled for the EFM32PG-STK3401A board.

In the following table, the column Name contains pin names. For example, PF4 means pin number 4 on PORTF, as used in the board’s datasheets and manuals.

Name

Function

Usage

PF4

GPIO

LED0

PF5

GPIO

LED1

PF6

GPIO

Push Button PB0

PF7

GPIO

Push Button PB1

PA5

GPIO

Board Controller Enable EFM_BC_EN

PA0

UART_TX

UART TX Console VCOM_TX US0_TX #0

PA1

UART_RX

UART RX Console VCOM_RX US0_RX #0

PD10

UART_TX

EXP12_UART_TX LEU0_TX #18

PD11

UART_RX

EXP14_UART_RX LEU0_RX #18

PC10

I2C_SDA

ENV_I2C_SDA I2C0_SDA #15

PC11

I2C_SCL

ENV_I2C_SCL I2C0_SCL #15

System Clock

The EFM32PG SoC is configured to use the 40 MHz external oscillator on the board.

Serial Port

The EFM32PG SoC has two USARTs and one Low Energy UART (LEUART).

Programming and Debugging

Note

Before using the kit the first time, you should update the J-Link firmware from J-Link-Downloads

Flashing

The EFM32PG-STK3401A includes an J-Link serial and debug adaptor built into the board. The adaptor provides:

  • A USB connection to the host computer, which exposes a mass storage device and a USB serial port.

  • A serial flash device, which implements the USB flash disk file storage.

  • A physical UART connection which is relayed over interface USB serial port.

Flashing an application to EFM32PG-STK3401A

The sample application Hello World is used for this example. Build the Zephyr kernel and application:

# From the root of the zephyr repository
west build -b efm32pg_stk3401a samples/hello_world

Connect the EFM32PG-STK3401A to your host computer using the USB port and you should see a USB connection which exposes a mass storage device(STK3401A). Copy the generated zephyr.bin to the STK3401A drive.

Use a USB-to-UART converter such as an FT232/CP2102 to connect to the UART on the expansion header.

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’ll see the following message on the corresponding serial port terminal session:

Hello World! arm