8 bit computer, building the ALU
I’m in the process of building the Arithmetic and Logic Unit (ALU) for my 8 bit computer. So far, as you can see, the complete B register and half of the A register are built. In the open space in the middle the ALU is going to be built using two SN74LS181 chips – each of which contains a 4 bit ALU. They can be cascaded to form broader units, able to process 8, 16 or even 32 and 64 bit words. Nothing that fancy here, mine will be 8 bits wide.