[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 ...

Arduino UNO R4 RA4M1 HOCO to External-Clock on EXTAL pin change setup code. With 10.00MHz external input; over-clocking to 80MHz, and under-clocking down to 5MHz. This is an update to the previous ...