Suoritinohjaus

Suoritinohjaus, also known as processor control or simply control in the context of computer architecture, refers to the part of a computer's central processing unit (CPU) that directs the operation of the processor. It tells the computer's memory, arithmetic logic unit (ALU), and input/output devices how to respond to the instructions it receives. The control unit is essentially the "brain" of the CPU, coordinating all its activities.

The control unit fetches instructions from memory, decodes them to understand what operation needs to be performed, and then generates control signals to execute that operation. These signals are sent to other components of the CPU, such as the ALU, registers, and memory unit, to perform the required tasks. It manages the flow of data within the CPU and between the CPU and other system components.

Key functions of the control unit include instruction fetching, instruction decoding, instruction execution, and managing the timing of operations through a system clock. It ensures that instructions are executed in the correct sequence and that data is moved to the appropriate locations at the right time. The design and efficiency of the control unit significantly impact the overall performance of a computer system. Different architectures employ various methods for implementing control units, such as hardwired control or microprogrammed control.