GCSE Computer Science (OCR) EXAM REVISED [100% VERIFIED]

GCSE Computer Science (OCR) EXAM REVISED [100% VERIFIED] Arithmetic Logic Unit (ALU) *Ans* Performs operations on data e.g. Addition, subtraction *Ans* CPU *Ans* Central Processing Unit Control Unit (CU) *Ans* Coordinating activities of the CPU Registers *Ans* Quick, small stores of data within the CPU Memory Address Register (MAR) *Ans* Holds memory address for data or a instruction about to be used by the CPU Memory Data Register (MDR) *Ans* Holds actual data or instruction Accumulator *Ans* Stores results of calculations in the ALU Program Counter (PC) *Ans* Holds memory address of the instruction for each cycle Fetch *Ans* The next instruction is retrieved by CPU from main memory Decode *Ans* The instruction is broken down and decided so computer can understand Execute *Ans* The CPU performs what the instructions told Embedded System *Ans* A computer system built within a large device e.g. Camera, washer, car Volatile *Ans* Memory loses its data when power of Non-volatile *Ans* Memory retains its data when power is lost Random Access Memory (RAM) *Ans* Read/write - function is to load open programs and operating system data currently in use - volatile Read Only Memory (ROM) *Ans* Can only be read, can't be changed, stores essential programs to be run in order to boot the computer - non-volatile Cache *Ans* A type memory that stores copies of frequently used data, much faster than RAM, lower capacity - closer to CPU Buses *Ans* Collection of wires that carry signals between various components of th