MarlinMarlin is an optimized firmware for RepRap 3D printers based on the Arduino platform. | Many commercial 3D printers come with Marlin installed. Check with your vendor if you need source code for your specific machine.
ArduRTOSReal Time Operating System Lessons using Arduino and The FreeRTOS Kernel
penny3 servos, 10 dollars hexapod
DigiOSMini OS emulator for Digispark (an Attiny85 based microcontroller).
arduinorequired (and optional) source files for the Arduino development environment, specifically the hardware/arduino sub-directory, to support xmega processors
hwmfDemo for Arduino Mega (ATmega2560) and an LCD. Got 2nd place at Revision 2020 wild compo.