[Damian Peckett] has implemented an Apple ] [, its 6502 processor, and a cassette port, all on an Arduino Uno. If that wasn’t enough, he also uses a PS/2 keyboard for input and outputs analog VGA.

An eForth for Arduino UNO/Nano implemented in C. .ino sketch file can be openned in Arduino IDE, no programmer to overwrite bootloader needed. Has 16-bit cells and stacks. Can read/write Arduino GPIO ...