EE 232 Digital Electronics http://www.engr.usask.ca/classes/EE/232

Prof. Seok-Bum Ko seokbum.ko@usask.ca 3b39, 5456

EE232 U of S

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•Course Description: Covers the theory of digital circuits and computer systems stressing general techniques for the analysis and synthesis of combinational and sequential logic systems

•Course Meetings: M,W,F 8:30am – 9:30am, 2B53E

•Textbook: Digital Systems; Principles and Applications, 8th edition, Prentice Hall, 2001, By Ronald J. Tocci and Neal S. Widmer EE232 U of S

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â€˘Exams: Mid-term: 25%, Final: 50% Dates and formats for these tests will be provided once the term is underway.

â€˘Homework: Homework will be assigned 8 times. Late homework will be accepted, with penalty, until the time the solutions are posted. No homework will be accepted once the solutions are posted. Homework will constitute 20% of the course grade.

â€˘Attendance: 5% or Quiz: 5 % EE232 U of S

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Text Coverage • • • • • • • • •

1 2 3 4 5 6 7 9 11

Introductory Concept Number Systems and Codes Logic Gates and Boolean Algebra Combinational Logic Sequential Logic Digital Arithmetic Counters and Registers MSI Logic Circuits Memory Devices (time permitting) EE232 U of S

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Class Schedule Week

Lecture

Assignments

Due Date

1

Ch. 1 & 2

2

Ch. 2 & 3

Ch. 2

Start of W3

3

Ch. 4

Ch. 3

Start of W4

4

Ch. 4 & 5

Ch. 4

Start of W5

5

Ch. 5

Ch. 5

End of W6

6

Ch. 6

7

Good luck to your mid-term exam!!

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Ch. 6

9

Ch. 7

10

Ch. 6

End of W9

Ch. 7

Ch. 7

End of W11

11

Ch. 9

Ch. 9

End of W12

12

Ch. 11

13

Ch. 11

Ch. 11

End of W13

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Good luck to your final exam!! EE232 U of S

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Ch1 Introductory Concepts 1.1 Numerical Representations • Analog : continuous • Digital: discrete (step by step)

1.2 Digital and Analog Systems • Digital Systems: a combination of devices designed to manipulate logical information or physical quantities that are represented in digital forms EE232 U of S

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â€˘ Advantages of Digital Techniques -

easier to design and store accuracy and precision are greater operation can be programmed less effective by noise more can be fabricated on IC chips

â€˘ Limitation of Digital Techniques The real world is mainly ANALOG!! To take adv. of digital tech. - convert analog inputs to digital - process the digital - convert the digital outputs to analog EE232 U of S

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1.3 Digital Number Systems

Decimal position values as powers of 10 EE232 U of S

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Binary position values as powers of 2 EE232 U of S

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Binary counting sequence EE232 U of S

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â€˘ What is the largest number that can be represented using eight bits? ans.) 111111112 = 25510 ; 2N-1 in general â€˘ Review Questions (p. 12) 1. 11010112 = (26+25+23+21+20)=10710 2. What is the next binary following 101112 in the counting sequence? 110002 3. What is the largest decimal value that can be represented using 12 bits? 212 â€“ 1 = 409510

EE232 U of S

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1.4 Representing Binary Quantities

(a) Open and closed switches representing 0 and 1, respectively (b) absence or presence of holes in paper tape representing 0 and 1, respectively EE232 U of S

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(a) Typical voltage assignments in digital systems (b) Typical digital signal timing diagram

EE232 U of S

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1.5 Digital Circuits/Logic Circuits • Digital Circuits = Logic Circuits • Digital IC: TTL, CMOS, NMOS, and ECL

A digital circuit responds to an input’s binary level (0 or 1) and not to its actual voltage EE232 U of S

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Review Questions • The exact value of an input voltage is critical for a digital circuit. ans.) False • Can a digital circuit produce the same output voltage for different input voltage values? ans.) Yes • A digital circuit is also referred to as a logic circuit. • A graph that shows how one or more digital signals change with time is called a timing diagram. EE232 U of S

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1.6 Parallel / Serial Transmission (a) Parallel transmission uses one connecting line per bit, and all bits are transmitted simultaneously; (b) Serial transmission uses only one signal line, and the individual bits are transmitted serially (one at a time).

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Review Questions â€˘ Describe the relative advantages of parallel and serial transmission of binary data. ans.) Parallel is faster; Serial requires only one signal line

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1.7 Memory When an input is applied to a circuit, the output will change its state, but it will remain in the new state even after the input is removed. This property of retaining its response to a momentary input is called memory.

Comparison of nonmemory and memory operation EE232 U of S

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1.8 Digital Computers

Functional diagram of a digital computer

EE232 U of S

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â€˘ Type of Computers -microcomputer, minicomputer (workstation), and mainframe. â€˘ Microcomputer - the smallest type of computer - consists of several IC chips; microprocessor, memory, and i/o interface â€˘ Microcontroller - designed to be used as a dedicated or embedded controller

EE232 U of S

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Review Questions • Explain how a digital circuit that has memory differs from one that does not. ans.) One that has memory will have its output changed and remain changed in response to a momentary change in the input signal. • Name the five major functional units of a computer. ans.) input, output, memory, arithmetic/logic, control • Which two units make up the CPU? ans.) control, arithmetic/logic • An IC chip that contains a CPU is called a microprocessor. EE232 U of S

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Summary • Analog (continuous) and digital (discrete) • Most quantities are analog, but digital techniques are superior to analog techniques. • Binary system is the basic system used in digital technology. • Digital or logic circuits operate on voltages that fall in prescribed ranges that represent either 0 or a binary 1. • Parallel (all bits simultaneously) and serial (one at a time) • Main parts of computers: I/O, control, memory and arithmetic/logic • Arithmetic + logic = CPU (Central Processing Unit) • Microprocessor: a microcomputer has a CPU that is on a single chip • Microcontroller: a microcomputer especially designed for dedicated control applications EE232 U of S

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