Computing 1.1 systems architecture

Question 1

CPU

Answer 1

The main part of the computer which is sometimes called the BRAIN that consists of the registers, ALU and control unit.

Question 2

Vonn Neumann Architecture

Answer 2

Computer architecture that forms the basis of most digital computer systems.

Question 3

Cache

Answer 3

Faster access memory for frequently used instructions and data.

Question 4

Fetch- Decode- Execute Cycle

Answer 4

The process of retrieving an instruction from the store, decoding it and carrying it out.

Question 5

Registers

Answer 5

Superfast onboard memory that each have a specific purpose: MAR, MDR,PC and ACC.

Question 6

MAR(Memory Address Register)

Answer 6

Holds the address of the data/instruction to be used/passed from the program counter. PART OF THE DECODE CYCLE

Question 7

MDR(Memory Data Register)

Answer 7

Holds the data fetched or to be written to the memory. PART OF THE EXECUTE CYCLE

Question 8

PC(Program Counter)

Answer 8

Holds the address of the next instruction to be executed. PART OF THE FETCH CYCLE

Question 9

ACC(Accumulator)

Answer 9

Hold the RESULT of the calculation

Question 10

What main factors affect the performance of the CPUs performance? (3 things)

Answer 10

The clock speed, cache size and the number of cores.

Question 11

Clock speed

Answer 11

HERTZ(GHz). It’s the number of instruction cycles that can be executed per second.

Question 12

Cache size

Answer 12

The LARGER the cache, the more that can be copied and stored without having to go back to the RAM(which takes more time to fetch data from). HOWEVER the bigger it is the slower it is.

Question 13

Number of Cores

Answer 13

The cores are responsible for the Fetch- execute cycle. The more cores there are, the more cycles that can be done at one time. HOWEVER it takes more time as more communication is needed to take place.

Question 14

Embedded Systems

Answer 14

is a computer that has been built to solve a specific function. eg. washing machine, microwave, traffic lights…

Question 15

RAM(Random Access Memory)

Answer 15

RAM is the main memory in that stores the information that your computer is actively using. VOLATILE- data is lost when power is lost.

Question 16

Virtual Memory

Answer 16

Using part of the hard disk as if it were RAM which allows more applications to be open than physical memory could hold.

Question 17

What happens in the FETCH cycle?

Answer 17

The PROGRAM COUNTER is loaded with the address of the next instruction. The address is then loaded into the MAR which is then sent to the RAM through the address bus and copied through the data bus to the MDR.

Question 18

What happens in the DECODE cycle?

Answer 18

In the DECODE cycle the instruction is sent to the CU through the data bus and decoded.

Question 19

What happens in the EXECUTE cycle?

Answer 19

In the EXECUTE cycle the outcome is stored in the accumulator.

Question 20

CU (control unit)

Answer 20

Controls how data moves around the CPU.

Question 21

ALU (Arithmetic Logic Unit)

Answer 21

Performs arithmetic equations and logical comparisons .

Question 22

ROM (Read Only Memory)

Answer 22

Memory can be read from i but cannot be written into. NONVOLITALE- data is not lost when power is turned off(permanent memory)