1.1 System Architecture

Question 1

What is an embedded system?

Answer 1

A computer designed for a dedicated function inside a larger device

Question 2

What is the clock speed?

Answer 2

It is the number of instructions a processer can carry out per second

Question 3

Why are Embedded systems efficient?

Answer 3

They are dedicated to a single task

Question 4

Why does an increasing number of cores increase the speed of the CPU?

Answer 4

More cores a CPU has, more instructions can be carried out at once (multitasking)

Question 5

What is cache?

Answer 5

Small component that stores frequently stored data

Question 6

Why does a larger cache increase the speed of a computer?

Answer 6

Gives the CPU faster access to more data

Question 7

Where does the CPU fetch instructions from?

Answer 7

RAM

Question 8

Where does the CPU copy memory address to?

Answer 8

MAR

Question 9

When does the PC become incremented?

Answer 9

When fetching an instruction?

Question 10

What is the purpose of the CU?

Answer 10

Sends timing signals

Sends Control signals

Question 11

Where are the instructions executed?

Answer 11

In the CU

Question 12

What is a register?

Answer 12

A small amount of high-speed random access memory contained within the processor

Question 13

What is the purpose of the program counter?

Answer 13

Holds the memory address of the next instruction to be fetched

Question 14

What is the purpose of the ALU?

Answer 14

Does all the calculations and logic operators

Question 15

What is the purpose of the Accumulator?

Answer 15

Holds the result of any calculations of the ALU

Question 16

What is the purpose of the MAR?

Answer 16

Holds the address about to be used by the CPU

Question 17

What is the purpose of the MDR?

Answer 17

Holds the actual data or instruction being processed by the CPU

Question 18

What is the purpose of the Address bus?

Answer 18

Carries memory addresses from the processer to other components

Question 19

What is the purpose of the Data bus?

Answer 19

Carries the actual data data between the processor and other components

Question 20

What is the purpose of the Control bus?

Answer 20

Carries control signals from the processer to other components.
Also carries the clock’s pulses

Question 21

What is a general purpose computer?

Answer 21

A computer designed to perform more than one task

Question 22

What is a computer?

Answer 22

An electronic device that takes an input; processes data and delivers and output

Question 23

What is the purpose of the CPU?

Answer 23

To fetch, decode and execute instructions

Question 24

What is the purpose of the ALU?

Answer 24

Responsible for arithmetic calculations

Responsible for logical decisions

Question 25

What are the key characteristics of the Von Neumann Architecture?

Answer 25

``` Central process uniting Single Control Unit Arithmetic Logic Unit Onboard Cache Internal Clock ```

Question 26

What is the Von Neumann structure based on?

Answer 26

Based on the concept of the stored-program concept

Question 27

What is the clock speed measure in?

Answer 27

Hz

Question 28

What happens if the clock speed increases?

Answer 28

More fetch-decode-execute cycles can happen - as a result leads to improved efficiency

Question 29

Where is the cache?

Answer 29

Near the CPU

Question 30

What is a core?

Answer 30

A complete copy of the CPU

Question 31

What is a quad-core processer?

Answer 31

``` Has 4 separate processing units each with its own: Accumulator ALU Registers Control Unit etc. ```

Question 32

What are the benefits of having a CPU with multiple cores?

Answer 32

Have more power to run multiple programs at the same time

Question 33

Why does doubling the number of cores simply not double the overall speed?

Answer 33

CPU cores have to communicate with each other, this takes time Many programs are not designed to make use of multiple cores

Question 34

What are the properties of embedded systems?

Answer 34

Lower power consumption Small size Rugged operating system Low cost per unit

Question 35

What are some examples of embedded systems?

Answer 35

Traffic light Domestic appliances Factory equipment Hospital equipment