CPU Clock

The control unit is always associated with the clock. The clock sends signals to the other devices of the CPU by control lines.

The CPU Clock Signal

The signals from the clock time all the action. So the action is synchronized and follows a schedule. The Instruction Pointer and the Instruction Register are used as pivots in the Fetch-Decode-Execute cycle. The process literally alternates between the Instruction Pointer, the Instruction Register, and the ALU. The decoding unit takes the Instruction in the Instruction Register and decodes it into signals that tell the CPU and ALU what to do in order to accomplish the instruction being run. The processes executed by this system are based on the instruction set of the computer.

Of course it goes a lot faster than this.

The Animated Computer

Dr. Jerome Heath