katef / eurorack-cpu

A CPU implemented in an analog modular synthesizer

This runs in the VCV Rack eurorack simulator.

I wrote a thread explaining the CPU on twitter
and a thread explaining just the ripple adder.

TODO list: https://github.com/katef/eurorack-cpu/issues/1

Here's the unannotated screenshot and here's a video of the whole thing running

Instruction formats:

00000: no-op (clears bus)
10ooo: output ALU op to bus
010rr: load reg from bus (keeps bus)
110rr: output register to bus
0110n: load ALU operand (clears bus)
0111i: output immediate to bus

ooo = alu op
rr = register number
n = alu operand
i = immediate

Fetch and Decode

and a video of it running

Data bus

3-Stage Clock

A single register

Register bank

Immediate value

ALU

Ripple carry adder