Once you have enough transistors on a board, though, one of the first layers of abstraction that arises is the Arithmetic Logic Unit ... perform seven functions: ADD, SUB, XOR, XNOR, AND, OR ...

and even arithmetic logic units. Add in some passives like capacitors and inductors, and a logic simulator may be the only tool you need to bring a design to life in the virtual world before ever ...

An earlier logic chip used as a building block for ... etc.). They included inputs and outputs for borrow and carry bits (addition and subtraction require carrying to and borrowing from the ...