PROCESSORS TOPIC 4

Question 1

What is a processor?

Answer 1

Also called CPU (central processing unit). A small chip that manage all instructions such as arithmetic, logic, I/O, and other basic instructions

Question 2

Performance of a CPU depends on:

Answer 2

1. Clock Speed
   - Number of pulses the CPU generates per second
2. Cache Size
   - Small amount of high-speed RAM built within the processor
3. Number of Cores
   - A processing unit within a CPU is known as a core, and it is capable of handling its own instructions

Question 3

CPU components

Answer 3

1. ALU (arithmetic and logic unit)
   - AND, OR and arithmetic calculation operation
2. Control Unit
   - Reads an instruction from memory
3. Registers and Buses
   - Address Bus, Control Bus, Data bus
4. System Clock
   - defines the clock cycle that synchronises all computer operations.

Question 4

What is Register

Answer 4

• To manipulate data within the computer (high speed storage for processing)

Question 5

Types of Registers

Answer 5

1. CIR (current instruction register
   - stores decoded and executed
2. ACC (accumulator)
   - stores data during ALU calculations
3. MAR (memory address register)
   - stores address of the memory location
4. MDR (memory data register)
   - stores data that is about to be written
5. PC (program counter)
   - stores the address where next instruction read can be found

Question 6

CPU instruction cycle

Answer 6

1. Fetch
2. Decode
3. Execute

Question 7

Fetch

Answer 7

• Both data and instruction can be stored in the MDR
• The next instruction is fetched from the memory address
• The contents of the MDR are then copied
• The PC is then incremented with +1

Question 8

Decode

Answer 8

• The instruction is then decoded so that it can be interpreted in the next cycle

Question 9

Execute

Answer 9

• Decode the instruction then execute
• Decoded instruction then be sent to set of control signals to appropriate components

Question 10

LMC (Little Man Computer)

Answer 10

• Is a simulator that mimics the modern computer architecture, known as Von Neumann architecture

Question 11

Mnemonic code and Numeric code of LMC

Answer 11

1. INP - 901 input data
2. ADD - 1XX - add data
3. SUB - 2XX - subtract data
4. STA - 3XX - store data
5. LDA - 5XX - load data
6. OUT - 902 - output data

Question 12

What is computer architecture

Answer 12

• It acts as an interface between hardware and software
• Also called as instruction set architecture

Question 13

Von Neumann architecture features:

Answer 13

• CPU was able to access the memory directly
• Von Neumann developed the idea of stored program concept

Question 14

GPU (Graphical processing unit)

Answer 14

• Made to rapidly access and modify memory in order to speed up the production of images and videos

Question 15

CPU vs GPU

Answer 15

CPU - general purpose processor that can perform wide range of tasks
GPU - specifically designed to handle the complexity of maths calculation for rendering graphics and videos