Microcontroller demo boards such as the Arduino UNO are ubiquitous on Hackaday ... His notes show he saw the barest way to operate an ATMega328, built it, tested, and moved on to the power supply ...

[Damian] wrote a simple assembler which translates the 6502 opcodes and address modes to instructions which can be executed by the Arduino’s ATmega328. To keep everything in ROM and make the ...