OCR SPEC terms list

Question 1

ALU

Answer 1

Arithmetic Logic Unit
Part of CPU where data is processed and manipulated.
Does maths and logic

Question 2

Control Unit

Answer 2

Part of CPU that manages instruction execution
Fetches and decodes instructions

Question 3

Register

Answer 3

Tiny bits of extremely fast memory located in the CPU
Where one piece of data or conntrol info is stored
Designed for a specific purpose

Question 4

PC (register)

Answer 4

Program Counter
A register which holds the address of the next instruction

Located in the control unit

Question 5

ACC

Answer 5

Accumulator
A register used to hold the data currently being processed by the central processor

Located in the ALU

Question 6

MAR

Answer 6

Memory Address Register
Stores the address of the current instruction (fetch phase) or data (execute phase) in use

Located in the CPU