Hey, thanks for the recommendations! I'll definitely look into the AVR instruction set. I'm not opposed to multibyte instructions but I'm trying for 8-bit instructions. I'm actually planning to use a special register that holds the ALU input so that I have more space for instructions in the actual instruction. It'll take more instructions since you'll have to set the ALU each time you need it changed, but as it's not a physical microcontroller, I'm not worried about running out of room. Do you think this is a feasible plan?