L10 - CISC and RISC

Question 1

What is CISC?

Answer 1

Complex instruction set computer:

Older approach

Multiple instructions in one instruction word

Different op code sizes

EG Intel x86

Question 2

What is RISC?

Answer 2

Reduced instruction set computer:

Smaller opcodes

same opcode length

e.g. ARM

Question 3

Why use CISC?

Answer 3

Simplifies compilers

Program takes less memory (fewer instructions needed)

Should improve performance

Question 4

Why use RISC?

Answer 4

One machine instruction per machine cycle

Register to register operations simplified to load and store

Simplified addressing modes

Simple instruction format - same for all instructions

Question 5

What is SISD?

Answer 5

Single instruction, single data stream

i.e. von neumann machine

Question 6

what is SIMD

Answer 6

Single instrucion multiple data stream

Processer applices same instruction to multiple data streams

Question 7

What is MISD

Answer 7

Multiple instruction single data stream

Set of processors with same data stream

Question 8

what is Mimd?

Answer 8

set of processors simultaneously execute different instruction sequences on different data sets