TSO that (second half) is how i implement it. The alu can do all logic ops using 3 possible outputs (xor, or, nor) and inverters in front of the a and b registers. !a is just inverting the a register and routing it into the main bus.
Anyways, I'm using microcode to translate 4-bit alu opcodes to the 5-bit codes it can interpret (I use the msb in my IS to indicate an alu op while in the main pipeline, so essentially 4-bit alu opcodes), so I can always replace one op with another with the slap of a torch
Anyways, I'm using microcode to translate 4-bit alu opcodes to the 5-bit codes it can interpret (I use the msb in my IS to indicate an alu op while in the main pipeline, so essentially 4-bit alu opcodes), so I can always replace one op with another with the slap of a torch