I was reading a bunch of home brew cpu sites and was wondering how I could add a hardware multiplier?
I know it can be done in software but I figure it would be faster if it is put in the hardware.
Adding a hardware multiplier to the Hack computer is a fairly big task. You will need to use one of the "always one" bits in the I-instruction to select multiplying in the ALU. The hardware multiplier itself basically implements the grade-school long multiplication algorithm in binary. For 16-bit unsigned multiply the 16 partial products are generated by ANDing the multiplicand by each bit of the multiplier, and the partial products are then added using 15 16-bit adders.
That's 256 ANDs, 225 Full Adders, and 15 Half Adders!