1.1 System Architecture

Question 1

CPU

Answer 1

The Central Processing Unit: The “brain” of the computer.

Question 2

Control Unit

Answer 2

Part of the CPU that manages the functions of all other parts of the CPU.`

Question 3

Decoder

Answer 3

The part of the CU which decodes the binary instructions fetched from memory.

Question 4

RAM

Answer 4

The main volatile memory into which programs are loaded from the hard drive.

Question 5

What is the Memory Address Register

Answer 5

Small fast memory used to store the RAM address of the next instruction.

Question 6

Memory Data Register

Answer 6

Small fast memory used to store the information collected from the RAM before processing.

Question 7

Program counter

Answer 7

Keeps track of the current instruction number of the program.

Question 8

Accumulator

Answer 8

Small, fast memory, used to keep track of the data currently being processed.

Question 9

Arithmetic Logic Unit

Answer 9

Does the basic mathematics and comparisons during processing.

Question 10

Bus

Answer 10

A physical connection between two elements of a computer system that allows the transfer of data.

Question 11

Cache

Answer 11

Incredibly fast, but very expensive volatile memory using in the CPU.

Question 12

Bridge (North/South)

Answer 12

Junctions on a motherboard where the bus connections are controlled and routed. North bridge deals with core functions, whilst the South bridge deals with the peripherals, input and output
devices and Secondary Storage.

Question 13

Von Neumann

Architecture

Answer 13

The method used by all modern computers to allow the programming of a machine to be changed depending on the required function.

Question 14

Fetch / Decode /

Execute Cycle

Answer 14

Basis of the von Neumann architecture – the repeated process where instructions are fetched from RAM, decoded into tasks and data, then carried out.

Question 15

Clock Speed

Answer 15

The number of FDE cycles that a CPU can carry out per second. Measured in Ghz. (1 Ghz = 109 cycles per second or 1,000,000,000hz)

Question 16

Cores

Answer 16

Some processors have multiple CPUs which can work in parallel, sequentially or can
multitask. Dual and Quad cores are common in modern PCs.

Question 17

Multi Core Processing

Answer 17

Some processors have multiple CPU cores on one chip. They all have their own Level 1 cache, but share Level 2 cache, allowing them to collaborate quickly on large tasks.

Question 18

Machine Code

Answer 18

A program, stored in binary, that the CPU undertakes the FDE cycle on. All programs must be in machine code to work.

Question 19

Instruction

Answer 19

A single line of machine code, containing the command and data location on which it is to be executed. Stored in binary.

Question 20

Opcode

Answer 20

The first part of the instruction, is the command.

Question 21

Operand

Answer 21

The second part of the instruction is the data on which to carry out the command. This may be actual data stored in binary form, or a memory location reference of where to find the data.