1.1 System Architecture

Question 1

Program Counter(PC)

Answer 1

Holds the address of the next instruction

Question 2

MAR(Memory Address Register)

Answer 2

Holds the address of the data/instruction to be fetched from the RAM

Question 3

MDR(Memory Data Register)

Answer 3

Holds the data/instruction fetched from the RAM

Question 4

ACC(Accumulator)

Answer 4

Holds the result of the calculation/operation done by the ALU

Question 5

CIR(Current Instruction Register)

Answer 5

Holds the current instruction being executed

Question 6

CU(Control Unit)

Answer 6

Handles movement of instructions and data around the computer, fetches, decodes, executes instructions, control signals that control hardware

Question 7

Why use Von Neumann Architecture?

Answer 7

Uses a stored program concept, stores the program instructions which are stored in the same place as the data which is used when running a program. Don’t have to run a program separate to data making it easier to set up and run system

Question 8

What holds the data/instruction fetched from RAM?

Answer 8

MDR(Memory Data Register)

Question 9

What holds the current instruction being executed?

Answer 9

CIR(Current Instruction Register)

Question 10

What holds the result of the calculation/operation done by the ALU?

Answer 10

ACC(Accumulator)

Question 11

What holds the address of the next instruction?

Answer 11

PC(Program Counter)

Question 12

What holds the address of the data/instruction about to be fetched from the RAM?

Answer 12

MAR(Memory Address Register)

Question 13

What 5 components are registers?

Answer 13

PC, MAR, MDR, ACC, CIR

Question 14

CPU:

Answer 14

Fetch, decode and execute instructions

Question 15

Fetch-Execute Cycle:

Answer 15

Fetches the next instruction from RAM, works out what to do with it, carries it out, increments PC by 1

Question 16

Cache:

Answer 16

Very fast memory in CPU, slower than registers, faster than RAM. Stores frequently used data that the CPU can access quickly. Greater storage than registers.

Question 17

Clock speed:

Answer 17

The number of instructions a single processor core can execute per second

Question 18

Cache size:

Answer 18

A larger CPU cache gives the CPU faster access to frequently used instructions without having to fetch these instructions from RAM. Improves performance

Question 19

Number of cores:

Answer 19

Each CPU core can process data independently. The more cores a CPU has the more instructions it can carry out at once

Question 20

Embedded systems:

Answer 20

Computers built into other devices. Dedicated systems so easier to design and produce

Question 21

ALU

Answer 21

Performs mathematical and logic operations, gateway between primary and secondary storage

Question 22

Registers:

Answer 22

Small amounts of high speed memory in CPU, store data needed for processing

Question 23

Difference between data and address:

Answer 23

Address: unique identifiers to locations in memory for the data - information

Question 24

Embedded systems:

Answer 24

Specific function, dishwashers, digital watches, electronic calculators, less processing power and power, cheap to design