Transcript Computer Organization IS F242

Computer Organization
IS F242
Course Objective
 It aims at understanding and appreciating the computing
system’s functional components, their characteristics, their
performance and their interactions.
 One need to understand Computer Architecture in order to
structure a program so that it runs more efficiently on a real
machine.
 One also need to understand it while selecting a system to
use. Such as CPU clock speed, memory size etc.
As a computer scientist, you should not treat it as a black box
which executes your program magically.
Basic Block Diagram of Computer
What are we going to learn in this
course?
 Basic structure and functions of a computer.
 Different components of a computer like
 CPU: Different Processor Design Issues and their Performance
 Memory Unit : Internal Memory Organization & External
Memory Organization
 Control Unit and its implementation
 I/O Unit
 Interconnection between them.
 Parallel Processing: Processor design issues, memory design
issues etc
 Multi-core processor architecture
Handout and Components
History of Computers
First Generation Computer: Vacuum Tubes
 Decimal machine rather
than a binary machine
 Mainly used for large
calculations.
 It had to be programmed
manually by setting
switches and plugging and
unplugging the cables.
 A ring of ten vacuum tubes
represented each digit.
 Very large machines
Vacuum Tube
First Generation Computer made of
Vacuum tubes
Second Generation: Transistors
 Transistors
 Made up of Silicon
 Silicon:
 Insulator
 It is made Semiconductor by Doping
 All the electronic devices are semiconductor devices
 And most of them are made up of transistors.
 Boolean logical gates are made of transistors.
 Combinational and sequential circuits – logic gates
 Integrated circuits – are made up of these circuits.
 Microprocessor is made up of these integrated circuits.
Moore’s Law
 Size of transistor is decreasing
 Number of transistors are increasing exponentially.
 Moore’s Law:
 Number of transistors doubles every 2 years.
 Gordon Moore: Co-founder of Intel
Moore’s Law
P4 Extreme Ed.
178 millions w/ 2MB L3
IBM POWER5 has
276 million transistors
Intel Dual-Core Xeon (P4-based Tulsa)
w/ 16MB unified L3: 1.328 billion, 2006
2,250
Core 2 Duo (Conroe)
291 millions, July 2006
42 millions
Exponential growth
Transistor count will be doubled every 18 months
 Gordon Moore, Intel co-founder
Stored Program Concept
 Von Neumann Model
 Program is first stored in the memory and each instruction is
then executed one by one by the processor.
Third Generation: Integrated Circuits
 In second generation, discrete components such as transistors
, resistors etc were manufactured separately and soldered on
the circuit board.
 This made the entire manufacturing process from transistor
to circuit board cumbersome and expensive
 Then Integrated circuits were introduced.
 SSI circuits
 LSI circuits
 VSLI circuits
 Later generations used LSI, VLSI and new technology.
Layers of Abstraction: from application
program to execution of program
High Level
Language
main() {
int i,b,c,a[10];
for (i=0; i<10; i++)…
a[2] = b + c*i;
}
Compiler
ISA
…
lw r2, mem[r7]
add r3, r4, r2
st r3, mem[r8]
Assembler
What is Computer Architecture?
Better (More Detailed) Answer
Application
Operating
System
Compiler
Instr Set Proc.
Firmware
I/O system
Datapath & Control
Digital Design
Circuit Design
Layout
Instruction Set
Architecture
Architecture
 Architecture is those attributes visible to the programmer
 Instruction set
 Number of bits used for data representation
 I/O mechanisms
 Memory addressing techniques
 Architecture Question:
 Is there a multiply/division instruction available?
Organization
 Organization is how features are implemented
 Control signals
 Interfaces between computer and peripherals
 Memory technology used
 Organization Question:
 Is multiplication is implemented by separate hardware or is it
done by repeated addition?
Architecture & Organization
 All Intel x86 family share the same basic architecture
 The IBM System/360 family share the same basic architecture
 This gives code compatibility
 At least backwards
 Organization differs between different versions
Example Processor: LC3
 Addressability is 16 bit – 216 address space
 8 Registers each 16 bit – it requires 3 bits to represent each
register
 Opcode is 4 bit long – 16 different instructions can be there
 Addressing Modes
 Example instruction:
 ADD R3,R4,R2
 0001 011 010 000 001 – machine equivalent of ADD
instruction
Multi-Processor and Multi-core
Processor Systems