Ch 1 Processor components

Components of CPU

Control unit, ALU, Buses, Registers

CU function

• Controls and coordinates CPU activity

• Directs flow of data between CPU and other devices

• Accepts next instruction and decodes the instruction into sequential steps

ALU functions

• Performs arithmetic and logic operations

• Perform bit shift operations in register

Types of System Bus

• Data

• Address

• Control

Bi-directional buses

Data bus, control bus

Uni directional bus

address bus

What does data bus move?

Data and instruction between system components

What does a wider data bus result in?

Larger values and more characters transmitted at a time

How many lines do data bus consist of?

8, 16, 32, or 64

What does address bus transmit and why?

memory addresses of words so data can be retrieved and sent back to processor

What does width of address bus determine?

Maximum possilbe memory capacity of the system

What are “words”?

unit that memory is divided into

What does control bus transmit?

command between system components

Types of control lines

bus request, bus grant, memory write, memory read, interrupt request