CS1104

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CS1104 Computer Organization

• PART 2 Computer Architecture
• Lecture 1
• Introduction

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• Textbook Computer Organization by Hamacher,
  Vranesic and Zaky. McGrawHill. I shall mention
  which parts of this book should be read.
• I shall provide slides and some notes. Please go
  through these too.
• Instructor Samarjit Chakraborty, Office S14
  06-04. Phone [phone]. Office hours
  Thursdays 12 to 2 pm. Please come and see me if
  you have questions/doubts
• There will be tutorials and assignments as
  before. Only 2 labs for this part on October 20
  27. Mid-term test on Oct 29, Wednesday

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Why study this course?

• The prospective software engineer, writing a
  program
• Why should I declare variable x to be an
  integer rather than floating point?
• Should I use array or linked-list as my data
  structure?
• Should I use multiplication, or implement it as
  repeated additions?
• The embedded systems programmer developing code
  for a Palm Zire 71 or Sony Clie or a programmable
  dishwasher
• How is the memory of this device organized? What
  instructions are supported?
• I need to program it in assembly
  language!!

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Why study this course?

• The prospective computer/hardware engineer (say
  working at Intel and developing the future
  Pentium Star100 processor)
• Needs to have a strong background in Computer
  Architecture

• Basic understanding of how a computer works and
  what is its internal organization
• Foundation for more advanced courses
• Necessary for hardware engineers as well as for
  all kinds of software developers

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This course is about

• Desktop computing Programs with integer and
  floating point data types, no regard for code
  size and power consumption
• Servers Database, file server, web and
  time-sharing applications for many users. Integer
  and string operations more important than
  floating-point operations
• Embedded computing Values cost, power and code
  size. Floating point operations might be
  restricted to reduce costs

Cost/Performance/Power/Size Tradeoffs!!!
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The global picture
Programming Languages, Compilers,Operating
Systems, Software Engineering
Instruction Set Architecture
PART 2
Datapath Control
Digital Design
PART 1
Circuit Design
Electrical Engineering
Layout
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Program to Execution The Flow
Link multiple machine-language programs to one
program
Program in High-level language (C, Pascal, etc)
Load program into computers memory
Compile program into assembly language
Assemble program to machine language
Execute program
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Organization
Bus
Processor
Memory
Devices
Control
Input
Cache
Datapath
Program Data
Output
Registers
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Representing instructions in computer Assembly
Language Add R0, R1, R2 means R2 ? R0
R1
Machine Language
000000 10001 10010 01000
00000 100000
6 bits 5 bits 5 bits
5 bits 5 bits 6 bits
op rs rt
rd shamt funct
Source Operand (register)
Basic operation
Destination register
Shift amount
Function code variants of the op field
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• The Clock
• Everything in one clock cycle OR each step in
  one cycle?
• Pipeline instruction execution?
• The Memory
• How much time does it take to access memory?
• How is it organized? Cache?
• The Bus
• How many buses? Avoid bus conflicts

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Questions!