The Radio Co-Processor is a 15.4 stack image flashed onto a Silicon Labs development kit or Thunderboard Sense 2. The 15.4 stack on the development kit communicates with the higher layers of the Thread stack running on the Raspberry Pi over a USB connection.
First, in order to flash the RCP, connect it to your laptop directly by USB.
We have provided two ways to get the required image to flash the RCP. You can use one of the following options:
- Use the pre-built image
ot-rcp
image file - Build the image file from the '
ot-efr32
' repository, which is listed on the Matter Repositories and Commit Hashes page
RCP image files for all demo boards are accessible through the Matter Artifacts Page. If you are using a pre-built image file, you can skip forward to Step #2: Flashing the RCP.
1. Clone the ot-efr32 repository
The ot-efr32 repo is located in Github here: https://github.com/SiliconLabs/ot-efr32.
You must have Git installed on your local machine. To clone the repo use the following command:
$ git clone https://github.com/SiliconLabs/ot-efr32.git
Once you have cloned the repo, enter the repo and sync all the submodules with the following command:
$ cd ot-efr32
>$ git submodule update --init --recursive
After updating the submodules you can check out the correct branch or commit hash for the system. Check the current branch and commit hash used here: Matter Branches and Commit Hashes
$ git checkout <commit hash>
2. Build the RCP
Once you have checked out the correct hash, follow the instructions here: https://github.com/SiliconLabs/ot-efr32/blob/main/src/README.md to build the RCP image for your EFR platform.
This process will build several images for your board. The filename of the image
to be flashed onto the board to create an RCP is 'ot-rcp.s37
'.
The output of the build process puts all the image files in the following
location: <git>/ot-efr32/build/<efr32xgxx>
Once you get the RCP image, either by downloading a prebuilt image or building the image file from the repo, you can flash it onto your device. This is done directly from your laptop and not through the Raspberry Pi, so make sure that the device is connected directly over USB to your laptop. Further information on flashing a Silicon Labs device is located here: How to Flash a Silicon Labs Device
Once you have flashed the image, the device becomes the RCP. Disconnect it from you laptop and connect it via USB to the Raspberry Pi.
The Raspberry Pi's Open Thread Border Router can then use the RCP to communicate with the Thread network.