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CPRE210: Introduction to Digital Design

• Instructor

– Arun K. Somani

– Tel: 294 0442

– Email: arun@iastate.edu

– Office Hours: MWF 10:00-11:00

• Teaching Assistant

– Will have one, see web a few days later

• Web Page is being setup

– http://vulcan.ee.iastate.edu/~arun/cpre210_A99/cpre210.html

• Text Book: Computation Structures by Ward and Halstead Jr.

– Will not cover the whole book

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Digital Design Area

• Rapidly changing field:

– vacuum tube -> transistor -> IC -> VLSI

– memory capacity and processor speed are doubling every 1.5 years

• Things you’ll be learning:

– Basic foundation of digital systems

– By the end of the semester you will be able to design, build, test, and program a simple digital computer

• Why learn this stuff?

– you want to call yourself a “computer scientist or engineer”

– First step towards design state-of-art systems

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Course Outline

• Learn general concepts in digital logic design

• Number systems and codes

• Digital representation of data

• Combinational and sequential logic

• Logic elements

• Design of digital systems and subsystems

• Introduction to computer-aided schematic capture systems

• Simulation tools

• Hardware description language

• Use of programmable logic devices

• Design of a simple digital computer

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Outline of Progress (How We Will Make It?)

• Topics wise– Fundamental key items - binary values, binary numbers system,

information representation, binary arithmetic– Mathematical foundation - a little bit about Boolean algebra,

Boolean logic, Boolean values, Logic operators, AND, OR, NOT, logic expressions, logic circuits, logic gates, truth tables

– Combinational circuits– Sequential circuits– General digital circuit design– datapath, control, design constraints, dynamic descipline static

discipline– computer design, ALU, registers, register file, bus, ROM, RAM,

Control, input/output– Tight coupling between lectures, home-works, and lab

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Grading

• Three one hour examination, each covering roughly one-third of the course material

• Each will be weighted the same• Homeworks will be assigned, collected, graded, and returned

regularly– Grading level 2, 1, and 0 (or some three equivalent levels)– 2: correct answer, 1: partial answer, and 0: (near) no answer– No late homeworks– No appeals– We will discard a few lower grades

• Weekly labs– Self contained, not graded but progress monitored– To get an “A” you have to complete all labs and so on...

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Policies

• Requesting academic accommodations– If you would like to request academic accommodations due

to a disability, please contact Disabled Student Services– Please present the disability academic accommodations,

letter to me and discuss your needs with me• Attention: Need Extra help. Talk to me

– If for any reason at any time you are feeling left out in the course, or need any extra help, feel free to contact me

– If you do not ask, there is no way for me to provide help• Collaboration

– You are free to consult others in interpreting assignments– However, submitted solutions to the assignments must be

done by you only (In other word no direct copy).

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• We are all familiar with decimal numbers• Information theory: discusses how to deal with information• We only deal with some aspects of it• Virtually all computers now store information in binary form• A binary number system has two digits, 0 and 1• Combination of binary digits represent various kind of information• Examples

– 01001011– It can be interpreted as an integer value, a character code, a

floating point number….• Non binary numbers are also possible• How do we represent negative numbers?

i.e., which bit patterns will represent which numbers?

Information Representation

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• Easy to represent

– Off and On

– Open and close switch

– Head and tail on a coin

– Polarity of magnetization

– 0 and nonzero voltage levels

• How to represent information in binary?

• Say we want to represent positive number 0 and 1

– 0 is 0 and 1 is 1

• say we want to represent red and green colors

– 0 is red and 1 is green (or vice versa)

• Say we want to represent fall and spring semesters

– 0 is fall and 1 is spring (or vice versa)

Why Binary?

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• Numbers 0 to 7– We use combination of digits

• 1 digits gives us two combination• 2 will yield four• 3 will yield 8

– Need three bits (binary digits)• What if we want to represent 16 alphabets - Need four bits• What if we want to represents numbers from 11 to 25?• Homework Problem:

– For each part below devise a scheme to represent, in binary, each set of symbols

• (A) Numbers: 0, 1, 2, 3, 4, 5, 6, 7• (B) Alphabets: A, B, C, D, E, F• (C) Integers from 21 to 36

More Complicated Examples