Last year I was asked by my robotics teacher to help her configure the BLE on the Arduino R4s to replace the bluetooth modules used with the R3s for motor control. I ended up swapping to WiFi, which was a lot more accessible and easier to deal with in a room full of devices, but it was still tricky to accomplish with a disturbing lack of documentation.
The software works because of the ESPS3 chip embedded into the R4. It operates by sending over UDP Packets. It's made to have been used with joysticks which is why it sends "x" and "y" values but it can be modified for other uses.
- Download the R4 boards pack
- Must have the R4 firmware completely updated (there is a safeguard in place for this in the code). Go to Tools --> Firmware updater
- The client has to run after the server has set up the wifi station. If you remove the client needing to be activated with a serial input, make sure you add some other kind of delay so it starts connecting to the wifi after the server has booted (~10s or so).
- This code just writes over the joystick values to the server. If you want (recommended), add a certain threshold for the joystick value to change before the packet sends so it doesn’t repeatedly send the same packet.
(Part of the builds I moved from google docs to GitHub on 6/19/26)