The CPU basics

What are the components of a real PC?
  1. CPU
  1. Memory
  1. Buses & I/O (input output)
  1. BIOS & Bus control circuitry
Are all the fundamental components of a real server the same as a PC?

Yes

Why do we need a cpu?
  • It performs operations and redirects data
  • Without the CPU the other components of a computer would be made redundant
What can the CPU do?

describe the following

Arithmetic operations

Adding, multiplying, subtracting, dividing

Memory access

Read and write data to / from memory

Decision making

Comparing numbers and letters, decide what to do next from that outcome

Control

Control the rest of the machine

What are the operations of a CPU?

give exsamples of the following

Memory operations
  • load
  • store
  • move
  • jump
  • offset
Arithmetic operations
  • add
  • subtract
Comparison operations
  • ==
  • ≠
  • >
  • <
Branch operations
  • Branch if 0
  • Branch if not 0

What are the three 'views' of a CPU?

Who would consern them selves with these topics and what do they involve

Hardware
  • Chip designers view
  • They care about the logic and packaging technology
  • Gates, cells, CMOS

Complementary Metal-Oxide-Semiconductor (method used to build circuits)

Microarchitecture
  • Processor designer view
  • Designing the logical organization so that would implement the Instruction Set Architecture
  • Pipelining, function units, caches, physical registers
Instruction Set Architecture (ISA)
  • Programers or compliers view
  • Instructions visible to the (system) programmer
  • Opcode. addressing modes, architectural registers...
What are the design principles that most manufacturers follow?
  1. All the instructions should be executed by the hardware
  1. Maximize rate that instructions are fetched
  1. Instructions should be quick and easy to decode
  1. Only loads and stores should reference memory
  1. Provide plenty of registers

Which is the lowest level view?

HARDWARE VIEW

What architecture do most computers follow?

Von Neumann

must learn the following block

What controls what the CPU is capable of executing?

The microarchitecture level defines what the CPU is capable of and what its instruction set is

explain what the following is

Accumulator CPU

This CPU has a single operand

Stack-based CPU

This CPU has a single operand and will work with a stack control

Register-based CPU

This CPU has two or more operands and will work with a stack control

VLIW

Very Long Instruction Word

SIMD

Single Instruction Multiple Data

MIMD

Multiple Instruction Multiple Data

RISC

Reduced instruction set computing

CISC

Complex instruction set computing

Von-Newman

Draw the architecture

What does the control unit do?

This controls the flow of data around the computer

Controls the operation of circuits

What does the arithmentic and logic unit do?

This performs arithmetic and logic operations

What does memory do?

Stores data for long periods of time, and is very large

What is a bus?

This is a set of bitwise connections

For example would like the ALU to the registers