8 bit breadboard CPU

Welcome to the github repo for my 8 bit breadboard CPU. I will add info and documentation as the project progresses.

unmarked image on bottom (04/2024)

Features

• 8 bit data, 8/16/.. bit instructions (up to 65.5k)
• 256B RAM, direct + indirect addressing
• Up to 65.5k instructions; 256 types, each up to 16 µstep
• Harvard architecture (to not need bootloader)

HW TODO

• Hook up I2C display
• Test full instruction set

SW TODO

• Add more complex instructions (stack?)
• (add kicad project)
• (add high level schematic)
• (EEPROM-arduino\display-decoder => negative number support)
• (Test driving I2C display without any libs)
• (Compiler)

State

Current state: all connectivity tested (with some jumper wires still). Basic instructions (+fibonacci program) functional, flags not connected to control yet.