3

The CPU

Now that we now how to build meaningful circuits like adders, multiplexers, shifter, multipliers, registers, and other memory storages, we can integrate them to create computer chips or devices, each of which serves a main purpose inside a computer.

We begin with the CPU: the Central Processing Unit, whose purpose is to perform calculations with data and make decisions.

A CPU consists of both combinational circuits (which perform calculations) and sequential circuits (to temorarily store the data we work with before it moves to permanent storage or to be output to the user, e.g., via the computer's screen.)

We can divide the CPU into two parts: (1) the datapath, which includes the ALU (Arithmetic-Logic Unit), which is where computations and decisions take place and where they are stored, and (2) the Control Unit, which oversees and controls the activity inside the CPU.