Control Unit Overview
The control unit is basically the main decision maker when it comes to the CPU. Or, you could think of it as the subconscious whereas the instructions executed are actually the conscious mind.
The control unit provides the CPU with the means to execute instructions. It has the following responsibilities:
- Retrieves instructions from memory
- Decodes the instructions
- Designates appropriate registers for the ALU
- Services interrupts
- Starts up the ALU
The control unit uses the program counter and status registers to keep track of the current state of the process.