1. COMS 361 Computer Organization
Title: Introduction to COMS 361
Date: 08/26/2004
Lecture Number: 1

2. Announcements I try to make class announcements at this time
Like assignments, program due dates, etc…
Brush up on discrete math

3. Review
I try to give a brief review of what we covered in the last class to motivate you for this class
Pretty much an outline of the previous classes material

4. Outline
I try to give an outline of the topics we will cover in this class
If all goes well, the outline for this class becomes the review for the next class
Rules of the Game
Go through the syllabus and calendar
Overview of Computer Organization

5. COMS 361 - Syllabus Professor Paul F. Hemler New at the HSC this year
Office: Bagby 110
Office Hours:
MWF: 3:00pm - 4:00pm
TR: 10:00am - 12:00noon
By Appointment
There is no reason we cannot find and set-up a meeting time
Semester Schedule

6. COMS 361 - Syllabus Class Times: TR: 8:30am - 9:50am
My address:
My phone number: 223 – 6202
My home page
Course home page
Department home page

7. COMS 361 - Syllabus Course Objectives
To show a hierarchical approach (abstraction) to understand a complex system
Gain a thorough understanding of
Rudimentary digital design principles,
The organization and operation of digital computers,
Machine and assembly language programming and their relationship to high-level languages

8. COMS 361 - Syllabus Course Objectives (Cont.) To understand
Performance benchmarks,
The meaning of different computer specifications
To understand how architectural and organizational issues effect program design and execution

9. COMS 361 - Syllabus Course Textbook
Computer Organization and Design: The Hardware/Software Interface, second edition by David A. Patterson and John L. Hennessy

10. COMS 361 - Syllabus Course Grading Policy
Straight-up, no curves, tricks, or illusions
Letter
Points A A- B+ B B-
Letter
Points C+ C C- D+ D F
0 - 59

11. COMS 361 - Syllabus Point Distribution Homework 20% Projects 25% Exams
30%
Final Exam

12. COMS 361 - Syllabus Homework: 20%
Homework assignments to help you understand the book material
No late homework will be accepted
Homework is due at the start of class on the due date

13. COMS 361 - Syllabus Homework: 20% (Cont.)
Write your solutions clearly and concisely on the paper you hand in
The work you hand in is a reflection of you
Make it look good and easy for me to evaluate
Put a box around you final answer

14. COMS 361 - Syllabus Exams: 30% Exam Exam Date Weight 1 10/12/04 15% 2
Two exams spaced throughout the semester
Closed book, Open mind
No make-up exams unless your absence is excused
Exam
Exam Date
Weight 1
10/12/04
15% 2
11/18/04

15. COMS 361 - Syllabus Final Exam: 25%
Mandatory on the assigned date and time.
Cumulative
Your last opportunity to demonstrate mastery of the course material
It is important you prepare for this exam

16. COMS 361 - Syllabus Class Attendance: Mandatory
I will keep a class roll
We will cover material that may not be in the book, but is  important for you to know
Class is fun, interesting, and informative
Your third unexcused absence get you a special meeting with me

17. COMS 361 - Syllabus Class Attendance: (Cont.)
Your sixth unexcused absence gets you
A letter from the Dean
Grade Drop of a letter (B- goes to a C-)
Class roll taken at the start of class (8:30 sharp)
If you miss the roll but are in the class, see me at the end of class

18. COMS 361 - Syllabus Class Attendance: (Cont.)
There are good reasons for missing a class
Sickness, death in the family, ...,
You will be excused from the class if you let me know before the class you intend to miss
Send , call me, stop by, ... 
There are no reasons for anyone to have unexcused absences

19. COMS 361 - Syllabus Commitment:
You should expect to spend 9 hours a week on this class
3 hours in class
2 hours reading the text book
4 hours doing homework/projects
Less than 4 hours or more than 12 hours per week means there is something is wrong

20. COMS 361 - Syllabus Extra curricular activities:
Let me know if your play a sport that will require travel and missing class
You should have a schedule of those classes you will miss
Share it with me ASAP

21. Course Content Introduction to computer organization
Using the MIPS RISC architecture
Quantitative performance
Assembly language
Number representations
Digital logic design
Datapath and control circuits
Pipelining

22. Course Content Memory hierarchy, fast but inexpensive
Input and output devices

23. COMS 361
Course Calendar

24. Computer Organization
Rapidly changing field:
Vacuum tube -> transistor -> IC -> VLSI doubling
Doubling every 1.5 years:
Memory capacity
Processor speed
(Due to advances in technology and organization)

25. Overview Why learn this stuff?
You want to call yourself a “computer scientist”
You want to build software people use (need performance)
Knowing how a program is executed helps one write better programs!

26. Overview
You need to make a purchasing decision or offer “expert” advice
Impress co-workers by knowing what computer specifications mean

27. Types of Computer Systems
Computers can be put into three categories
Desktop

28. Types of Computer Systems
Servers

29. Types of Computer Systems
Embedded Computer Systems

30. Desktop Computer Systems
For “General-Purpose” Use
Word-Processing, Web surfing, Multimedia, etc.
Computation and Programming
What’s in the box
Microprocessor
Memory - Synchronous DRAM
Hard disk(s), CDROM/DVD, etc.
I/O - mouse, keyboard, video card, monitor, network, etc.
Important Issues:
Performance - how fast is “fast enough”?
Basic capabilities (and expandability)
Cost

31. Server Computer Systems
Large-Scale Services
File storage
Computation
Transaction Processing, Web
What’s in the Box(es)
Microprocessor(s)
Hard disks
Network Interface(s)
Important issues:
Performance
Reliability, availability
Cost
One Rack-Mount PC Unit (Google uses ~ 10,000)

32. Embedded Computer Systems
Computer as part of larger system
Consumer electronics, appliances
Networking, telecommunications
Automotive / aircraft control
What’s in the box
Microcontroller / Microprocessor
Memory: RAM, ROM; Disk
Special-purpose I/O (including analog stuff)
Important issues
Cost, Power Consumption
Performance (against real-time constraints)
Reliability and Safety

33. Computer System Organization
“Five classic components”
Processor
Input
Control
Datapath
Output
Memory 7

34. Computer System Operation
Executing Programs - the “fetch/execute” cycle
Processor fetches instruction from memory
Processor executes “machine language” instruction
next
instr
Load Data
Perform Calculation
Store Results
OK, but how do we write useful programs using these instructions?
Processor
Control
Datapath
Memory
Address
Instruction 8

35. Abstractions Designers use abstraction to manage complexity
Focus on pertinent information
Suppress unnecessary detail
Example: Auto controls
Well-understood interface (inputs, outputs)
Details suppressed 55 E F 9

36. Languages Machine Language High-Level Language (C) c = a + b; Compiler
Assembly Language
add R8,R1,R2
Assembler
Machine Language

37. Instruction Set Architecture
The most important abstraction of computer design
Software
Compiler
Application Programs
Operating System
Application
Instruction Set Architecture
Interface between SW & HW
Logic - gates, state machines, etc.
Circuit - transistors, etc.
Layout - mask patterns, etc.
Hardware
Processor
I/O System 12

38. Top 5 Reasons to Study MIPS
5. It’s in the book
4. It’s used in many applications
3. Learning its architecture and implementation exposes you to important concepts
2. It’s relatively simple and easy to implement (compared to other architectures)
1. Ideas presented using MIPS generalize to other architectures (even the 80x86!)

39. Under the Hood: The Pentium 4
Die Photo
Package

40. What is a computer? Our primary focus:
The processor (datapath and control)
Implemented using millions of transistors
Impossible to understand by looking at each transistor
To deal with this complexity, we need...

41. Abstraction Delving into the depths reveals more information
An abstraction omits unnecessary details, helps us cope with complexity
One set of abstractions for computer organization entails the conversion of a program written in a high-level language so it can execute on a specific architecture

42. Abstraction

43. Instruction Set Architecture
A very important abstraction
Interface between hardware and low-level software
Standardizes instructions, machine language bit patterns, etc.
Advantage:
Different implementations of the same architecture
Disadvantage:
Sometimes prevents using new innovations

44. Instruction Set Architecture
Modern instruction set architectures:
80x86/Pentium/K6
PowerPC
DEC Alpha
MIPS
SPARC HP

45. Where we are headed Performance issues (Chapter 2)
Vocabulary and motivation
A specific instruction set architecture (Chapter 3)
Arithmetic and how to build an ALU (Chapter 4)

46. Where we are headed
Constructing a processor to execute our instructions (Chapter 5)
Pipelining to improve performance (Chapter 6)
Memory
Caches and virtual memory (Chapter 7)
I/O (Chapter 8)

47. Key to getting a good grade
Read the book
Before class and again after class
Understand class material
There is a reason things are the way they are
Ask questions
Do all the homework
Work Hard: Material is fascinating