EFM32 Pearl Gecko Starter Kit

Overview

The EFM32 Pearl Gecko Starter Kit EFM32PG-STK3402A contains an MCU from the EFM32PG family built on an ARM® Cortex®-M4F processor with excellent low power capabilities.

EFM32PG-SLSTK3402A

EFM32PG-SLSTK3402A (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 a touch slider

  • Humidity, temperature, and inductive-capacitive metal sensor

  • On-board Segger J-Link USB debugger

For more information about the EFM32PG SoC and EFM32PG-STK3402A board:

Supported Features

The efm32pg_stk3402a board configuration supports the following hardware features:

Interface

Controller

Driver/Component

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

TRNG

on-chip

true random number generator

The default configuration can be found in the defconfig file:

boards/arm/efm32pg_stk3402a/efm32pg_stk3402a_defconfig

The default configuration when building for this EFM32JG12B SoC can be found in another defconfig file:

boards/arm/efm32pg_stk3402a/efm32pg_stk3402a_defconfig_jg

Other hardware features are currently not supported by the port.

EFM32 Jade Gecko SoC

The EFM32 Pearl Gecko Starter Kit EFM32PG-STK3402A can also be used to evaluate the EFM32 Jade Gecko SoC (EFM32JG12B). The only difference between the Pearl Gecko and the Jade Gecko is their core. The Pearl Gecko contains an ARM® Cortex®-M4F core, and the Jade Gecko an ARM® Cortex®-M3 core. Other features such as memory and peripherals are the same.

Code that is built for the Jade Gecko also runs on an equivalent Pearl Gecko.

To build firmware for the Jade Gecko and run it on the EFM32 Pearl Gecko Starter Kit, use the board efm32pg_stk3402a_jg instead of efm32pg_stk3402a.

Connections and IOs

The EFM32PG12 SoC has twelve GPIO controllers (PORTA to PORTL), but only four are currently enabled (PORTA, PORTB, PORTD and PORTF) for the EFM32PG-STK3402A board.

In the following table, the column Name contains pin names. For example, PE2 means pin number 2 on PORTE, 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 four 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-STK3402A 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-STK3402A

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_stk3402a samples/hello_world

Connect the EFM32PG-STK3402A to your host computer using the USB port and you should see a USB connection which exposes a mass storage device(STK3402A). Copy the generated zephyr.bin to the STK3402A 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