Silicon Labs WFX Raspberry Pi Documentation

This guide is meant to be read after the WF200 Quick Start Guide (qsg166-wf200-wifi-devkit.pdf from https://www.silabs.com/). It covers steps needed to develop on a Raspberry Pi with a WFX EXP after trying basic Wi-Fi demos. All this documentation assumes that the Raspberry Pi is running the latest image from the releases page

WARNING: CHANGE THE HOSTNAME BEFORE CONNECTING THE RASPBERRY PI TO A NETWORK

Connecting to the Raspberry Pi

The default settings to access the Raspberry Pi are:

• hostname: silabs-pi-demo
• user: pi
• password: default_password

Changing the hostname

If two machines have the same hostname on a network, it becomes hard to tell which one we connect to. This can happen if two Raspberries with the same SD card image are plugged on the same network. To be sure this issue will not happen, it is strongly recommended to change the hostname just after running the Quick Start Guide demos.

From a shell on the Raspberry (either directly or through a SSH client like PuTTY or MobaXterm):

1. Run sudo raspi-config
2. Select Hostname
3. Choose a meaningfull, unique, hostname like pi-<your place>-<your login name>
4. Reboot
5. If connected through SSH, change the hostname in the SSH client session.

Connecting to a network

Once hostname has been changed, it is possible to plug the Raspberry Pi on a DHCP capable network. Then, just use SSH with the configured hostname (user is pi) to access the board.

Stand alone use

The Raspberry Pi can also be used directly like a PC, with a keyboard, mouse and screen plugged to it. This can be useful for troubleshooting network issues.

Bus change

By default, the Raspberry Pi is configured to use SDIO. To change to SPI, run wfx_bus --set spi. For checking bus mode, use wfx_bus --show. Do not forget to reboot after a bus change.

Wi-Fi connection

To experiment with Wi-Fi, it is possible to use the helper scripts wfx_sta and wfx_ap, they just wrap some of the most used tools and configurations. To get usage and supported features, run the desired tool with --help.

Enabling combo mode

To enable a second (virtual) interface a.k.a. combo mode, run iw dev wlan0 interface add wlan1 type managed.

Note: both interfaces cannot be in the same mode (station or access point) at the same time.

Repository contents

• demos/ mainly hosts two scripts (wfx_demo_station and wfx_demo_ap) that can be used to test the Wi-Fi. These scripts contain the usual commands for setting up basic station and access point so it is possible to use them as reference for custom applications> In this case, first copy the script outside of the repository (e.g. /home/pi/custom_scripts) to avoid issues when updating the repository.

• examples/ contains an example for a custom PDS file.

• overlays/ contains specific device tree overlays for the Raspberry Pi.

• scripts/ contains tools to configure and install WF200. Each script's documentation is accessible with --help option or at the top of the file.

• update/ contains tools to update the SD card on which it is supposed to be installed.

• pds_compress/ contains tool to process PDS files.

• test_feature/ contains tools to test the RF using a tone or modulated output. Refer to https://github.com/SiliconLabs/wfx-linux-tools/blob/master/test-feature/README.md for more details on testing.

Updating the tools

cd /home/pi/siliconlabs/wfx-linux-tools/
git fetch
git checkout origin/SD3
./install.sh

In case of startup issues

Use some of trace_ scripts under scripts to gather traces

Under examples/ are 2 logs of the init phase:

• SDIO init: retrieved using trace_sdio_startup
• SPI init: retrieved using trace_spi_startup