EFR32xG28 Explorer Kit (xG28-EK2705A)

Overview

The EFR32xG28 Explorer Kit is a small form factor development and evaluation platform based on the EFR32xG28 System-on-Chip. The EFR32xG28 Explorer Kit is focused on rapid prototyping and concept creation of IoT applications for Sub-GHz and Bluetooth LE like Wi-SUN, Amazon Sidewalk, Z-Wave, Wireless M-Bus, and proprietary networks.

Hardware

  • EFR32ZG28B312F1024IM48 SoC

  • CPU core: ARM Cortex®-M33 with FPU

  • Flash memory: 1024 kB

  • RAM: 256 kB

  • Transmit power: up to +10 dBm (2.4 GHz) and +14 dBm (sub-GHz)

  • Operation frequency: 2.4 GHz and sub-GHz

  • Crystals for HFXO (39 MHz) and LFXO (32.768 kHz) on the board

For more information about the xG28 SoC and Explorer Kit, refer to these documents:

Supported Features

The xg28_ek2705a 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.

System Clock

The xG28 SoC is configured to use the HFRCODPLL oscillator at 78 MHz as the system clock, locked to the 39 MHz crystal oscillator.

Serial Port

The xG28 SoC has 1 USART and 3 EUSARTs. USART0 is connected to the board controller and is used for the console.

Programming and Debugging

The xg28_ek2705a board supports the runners and associated west commands listed below.

flash debug

Flashing

Connect the Explorer Kit 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 xg28_ek2705a 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! xg28_ek2705a

Bluetooth

To use Bluetooth functionality as well as other wireless functionality, run the command below to retrieve necessary binary blobs from the Silicon Labs HAL repository.

west blobs fetch hal_silabs

Then build the Zephyr kernel and a Bluetooth sample with the following command. The Observer sample application is used in this example.

# From the root of the zephyr repository
west build -b xg28_ek2705a samples/bluetooth/observer