3.1 computer architecture Flashcards
1
Q
what is the role of the CPU
A
processes instructions and data input into computer so result can be output
2
Q
what is a microprocessor
A
- integrated circuit contained on single chip
- accepts data into computer & processes into information ready for output
3
Q
what are the components in a CPU
A
- units: ALU, CU
- registers: PC, MAR, MDR, CIR, ACC
- buses: address bus, data bus, control bus
4
Q
purpose of CU
A
- control operation of memory
- sends control signals that manage transfer of data and instructions within CPU
- initiates each step of FDE cycle
5
Q
purpose of ALU
A
- perform arithmetic calculations or logical operations
- use ACC to temp store data
6
Q
purpose of PC
A
- stores address of next instruction
- to be fetched from memory
7
Q
purpose of MAR
A
- store address of instruction
- to retrieve data from specific memory location
8
Q
purpose of MDR
A
- store data from address in MDR
- send data to CIR
9
Q
purpose of CIR
A
- store instruction
- which CPU currently decoding/executing
10
Q
purpose of ACC
A
- hold temporary values from calculations
- worked on by ALU
11
Q
what are registers
A
- small areas of storage in CPU
- extremely fast to access
12
Q
purpose of control bus
A
- carries control signals from CU to other components
- carries read/write signals from CPU to RAM
13
Q
purpose of data bus
A
- bidirectional
- write operation: carry data to be written MDR –> RAM
- read operation: carry data RAM –> MDR
14
Q
purpose of address bus
A
- unidirectional
- carry addresses MAR –> RAM
- indicate which address will be selected
15
Q
what is broad process of FDE cycle
A
fetch: instruction fetched from RAM –> CPU
decode: instruction decoded by CU to determine what type of instruction it is
execute: instruction executed, usually by ALU
