This is an Arduino sketch to remotely trigger a Nikon camera by flashing an IR LED. I used George Christidis's measurements for setting the timing.
To compile the project you can use either the Arduino IDE or the CLI:
arduino-cli compile --fqbn arduino:megaavr:nona4809
To upload it to your Arduino board:
arduino-cli upload -p /dev/cu.usbmodem1101 --fqbn arduino:megaavr:nona4809