ExpressLRS Joystick

Use your ExpressLRS 2.4GHz Radio as a joystick for your PC/Mac simulator using an Arduino microcontroller and the actual ExpressLRS receiver.

Why this project?

To connect your radio to your favourite simulator you basically limited to the following options:

• Using USB wire
• Bluetooth Joystick
• Betaflight/FC Joystick

This project provides another wireless connectivity option with the maximum rate of 500Hz (2ms).

Hardware

• Microcontroller: Seeed Studio XIAO SAMD21

  • Seeed Studio official site
  • Amazon
  • Aliexpress

• Receiver: BETAFPV ExpressLRS Lite Receiver with Flat SMD Ceramic Antenna

  • BETAFPV official site
  • Amazon
  • Aliexpress

Wiring diagram

Flashing controller

Connect SAMD21 controller to the Mac via USB. Wait for the Arduino disk to mount and the yellow led to light up on the board.

Validate board interface is available:

$ ls -l /dev/cu.usbmodem*
/dev/cu.usbmodem14301

The board is ready for the firmware upload.

The firmware requires platformio framework to be installed:

$ brew install platformio

To build and upload firmware use the following make commands:

$ make build
$ make upload

Once upload is done, Arduino disk will be forcefully unmounted and yellow led power off. The microcontroller is now in the USB passthrough mode. In order to upload firmware again, it requires to put board to bootloader mode.

Flashing ExpressLRS receiver

Firmware supports direct flashing from the ExpressLRS configurator using BetaflightPassthrough flashing method.

Acknowledgments

Based on the following projects:

• https://github.com/pfeerick/USB_ELRS_Receiver
• https://qiita.com/kobatan/items/40728fbb625057d9f42b
• https://github.com/mikeneiderhauser/CRSFJoystick