1.1.1 Glossary (Systems Architecture)

Question 1

Fetch-execute Cycle

Answer 1

Instructions are fetched one by one from main memory, decoded, and then executed by the processor. This cycle repeats until the program is complete

Question 2

CPU (Central Processing Unit)

Answer 2

A chip within the computer which controls the operation of all parts of the computer and decodes then executes program instructions.

Question 3

ALU (Arithmetic Logic Unit)

Answer 3

The part of the CPU responsible for arithmetic and logical operations.

Question 4

Processor Cache

Answer 4

High speed memory built into the CPU. Instructions are copied to cache memory allowing them to be accessed more quickly and therefore increasing the speed of the CPU.

Question 5

Register

Answer 5

A small area of memory within the CPU where data is stored temporarily to avoid the delay in copying to and from main memory,

Question 6

Von Neumann Architecture

Answer 6

The design on which most computers are based. It defines several registers along with the fetch-execute cycle and how the CPU interacts with main memory.

Question 7

MAR (Memory Address Register)

Answer 7

A register. It contains the address of the instruction currently being read from or written to main memory.

Question 8

MDR (Memory Data Register)

Answer 8

A register. It contains the instruction which has just been copied from main memory.

Question 9

Program Counter

Answer 9

A register. It contains the address of the next instruction to be fetched from memory. It is updated each time a new instruction is fetched to contain the address of the next needed instruction.

Question 10

Accumulator

Answer 10

A register. Stores the result of the last operation.