The arithmetic logic unit (ALU) part of a CPU is usually capable of performing various arithmetic, bitwise, and comparison operations on binary numbers. In our simple breadboard CPU, the ALU isĀ justĀ able to add and subtract. It’s connected to the A and B registers and outputs either the sum of A+B or the difference of A-B.

Videos

Schematic

(coming soon!)

Parts list

QuantityDescription
1Breadboard
274LS86 (Quad XOR gate)
174LS245 (Octal bus transceiver)
274LS283 (4-bit binary full adder)
8Red LED