...the type of counting desired. They will count up or down by ones, twos, or more. In electronics, counters can be implemented quite easily using register-type circuits such as the flip-flop, and a wide variety of classifications exist: • Asynchronous (ripple) counter – changing state bits are used as clocks to subsequent state flip-flops • Synchronous counter – all state bits change under control of a single clock • Decade counter – counts through ten states per stage • Up/down counter – counts both up and down, under command of a control inputMontgomery • Ring counter – formed by a shift register with feedback connection in a ring • Johnson counter – a twisted ring counter • Cascaded counter • modulas counter. Each is useful for different applications. Usually, counter circuits are digital in nature, and count in natural binary. Many types of counter circuits are available as digital building blocks, for example a number of chips in the 4000 series implement different counters. Occasionally there are advantages to using a counting sequence other than the natural binary sequence—such as the binary coded decimal counter, a linear feedback shift register counter, or aGray-code counter. Counters are useful for digital clocks and timers, and in oven timers, VCR clocks, etc. Asynchronous (ripple) counter An asynchronous (ripple) counter is a single JK-type flip-flop, with its J (data) input fed from its own inverted output. This circuit can store one bit, and hence...
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... (c) (i) | | | | | | | | S (p,q,r) = p | | | | | | | | T (p,q,r) = pq’ + p’q = p XOR q | | | | | | | | U (p,q,r) = q’r + qr’ = p XOR r (ii) (d)(i) Multiplexer How it works: * A multiplexer is a combinational circuit which connects multiple input lines to a single output, allowing only a single selected input signal to be passed to the output line at a time. * An Input signal is selected to be passed to output based on selection code which is implemented as two select lines. Typical Inputs and Outputs: * Consider a 4 -to -1 Multiplexer, typical inputs include four input lines labelled C0, C1, C2 and C3, along with two select lines labelled S0 and S1. * Output include single output line labelled F. Labelled diagram of 4-to-1 Multiplexer: (ii) Jk Flip Flop How it works: * A JK flip-flop is a sequential circuit which has two inputs that are similar to that of an S-R flip-flop, however all possible combinations of input values are valid. * If only the J input is asserted, the result is a set function, causing the output to be 1; if only the K input is asserted, the result is a reset function, causing the output to be 0. * When both J and K are 1, the function performed is referred to as the toggle function: the output is...
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...TTL Cookbook BY Don Lancaster A Division of M t i c e Hall ComputerPublishing 11 711 Nonh College, Cmel, Indiana 46032 USA " 1974 by SAMS A Division of Prentice Hall Computer Publishing. All rights reserved. No parts of this book shall be reproduced, stored in a retrieval system, or transmitted by any means. electronic, mechanical, photocopying, recording, or otherwise, without written permission from the publisher. No patent liability is assumed with respect to the use of the information contained herein. While every precaution has been taken in the preparation of this book, the publisher assumes no responsibility for errors or omissions. Neither is any liability assumed for damages resulting from the use of the information contained herein. International Standard Book Number: 0-672-21035-5 Library of Congress Catalog Card Number: 73-90295 Interpretation of the printing code: the rightmost double-digit number of the first column is the year of the book's printing; the rightmost double-digit number of the second column, the number of the book's printing. For example, a printing code of 92-23 shows that the twenty-third printing of the book occurred in 1992. Printed in the United States of America. Preface I don't like to revise books. Correct, yes. Revise, no. So I won't. A book becomes history the instant it appears in print. To tamper with history messes with what others and I were thinking at the time and distorts the way things...
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...either ‘high’ (5 V) or ‘low’ (0 V) with respect to each other. The high state is often known as a logic one ( 1) and the low known as a logic ( 0 ). 1.2 Data transmission. The bus in a microprocessor system transmit data in parallel form. [pic] Figure : 1 Data can also be transmitted in serial form [pic] Figure : 2 1. Decimal Number In everyday situations, a system of counting using a base of ten is employed. This is known as a decimal system, and its main justification for use is often quoted as being that human beings have ten fingers with which to count. A decimal number is composed of one or more digits chosen from a set of ten digits {0, 1, 2, 3, 4, 5, 6, 7, 8, 9} Base number is 10. The weights are all multiples of 10. Example: 3 5 7 ----- digits 102 101 100 ----- weights as powers of 10 100 10 1 ----- actual weight value __________________ 300 50 7 ----- components of number = 357 1. Binary Number A decimal system is not particularly suitable for direct use in electronic circuits. Due to practical limitations imposed by electronic devices, only two conditions are consistently...
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...computers. 3 The Abacus 4 Charles Babbage’s Analytical Engine 5 The Hollerith Machine 6 First Electronic Digital Computer 7 ENIAC 8 Colossus 9 • Describe some of the earliest forms of computers. 10 The Emergence of the Personal Computer 11 Objective • Discuss the transition of influence in the development of the personal computer. 12 Prior to the Personal Computer • Computers were very large. • Computers were very expensive. • Computers were quite rare. 13 History of the PC • Before the IBM PC – 1975 to 1981 • The IBM PC – 1981 • The IBM XT – 1983 • The IBM AT – 1984 • The IBM PS/2 – 1987 • Waning of IBM as the pace setter – 1987 to present 14 The First PC • Generally considered the MITS Altair • Introduced in January 1975 • Based on the 8080 Intel Processor • Sold for $395 in kit form 15 Before the IBM PC, personal computers used: • A variety of microprocessors • Many different architectures • A variety of operating systems 16 The IBM PC • Introduced on August 12, 1981 • Used the Intel 8088 microprocessor • Operated at 4.77 MHz • No hard drive • One or two single-sided floppy drives • Used MS-DOS 1.0 • Introduced the 8-bit ISA bus 17 The IBM PC brought standardization • Intel Microprocessors • Microsoft Disk Operating System (MS-DOS) • Architecture 18 The IBM XT • Introduced in 1983 • Included a 10 MB hard drive • Used MS-DOS 2.0 • 16-bit ISA Bus 19 The IBM AT • Introduced...
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...version incorporated Babbage's refinements developed during the creation of the Analytical Engine. Although Babbage never completed his invention in his lifetime, his radical ideas and concepts of the computer are what make him the father of computing. Father of the computer There are several people who could be considered as the father of the computer including Alan Turing, John Atanasoff, and John von Neumann. However, for the purpose of this document we're going to be considering Konrad Zuse as the father of the computer with his development of the Z1, Z2, Z3, and Z4. In 1936 to 1938 Konrad Zuse created the Z1 in his parent's living room. The Z1 consisted of over 30,000 metal parts and is considered to be the first electro-mechanical binary programmable computer. In 1939, the German military commissioned Zuse to build the Z2, which was largely based on the Z1. Later, he completed the Z3 in May of...
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...1 Design of Logic Circuits 1.1 Basic Revision of Logic Gates In the following chapter, we assume a two input logic gate with inputs A and B. 1.1.1 Simple Gates i. AND Gate The symbol and truth table for an AND gate is shown below: A B A.B 0 0 1 1 0 1 0 1 0 0 0 1 Summary: If inputs A AND B are high then the output is high Abbreviations: often a ‘.’ (dot) is used to signify the AND operator when writing Boolean equations. ii. OR Gate (Sometimes referred to as an Inclusive OR) The symbol and truth table for an OR gate is shown below: A B A+B 0 0 1 1 0 1 0 1 0 1 1 1 Summary: If inputs A OR B are high (or both) then the output is high Abbreviations: often a ‘+’ is used to signify the OR operator when writing Boolean equations. iii. NOT Gate The symbol and truth table for an NOT gate is shown below: A 0 0 1 A 0 1 2 Summary: Output is NOT what the input is. They are also called 'inverters'. Abbreviations: Many. Sometimes a line above the thing that is being notted, sometimes a dash ‘'’ and sometimes an ‘!’ exclamation mark 1.1.2 Complex Gates i. NAND Gate Made by combining an AND gate and a NOT gate. The equivalent circuit is: The symbol and truth table for an NAND gate is shown below: A A .B 0 0 1 1 0 1 0 1 1 1 1 0 A B A+ B 0 0 1 1 ii. B 0 1 0 1 1 0 0 0 NOR...
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...Fourth Edition, last update November 01, 2007 2 Lessons In Electric Circuits, Volume IV – Digital By Tony R. Kuphaldt Fourth Edition, last update November 01, 2007 i c 2000-2010, Tony R. Kuphaldt This book is published under the terms and conditions of the Design Science License. These terms and conditions allow for free copying, distribution, and/or modification of this document by the general public. The full Design Science License text is included in the last chapter. As an open and collaboratively developed text, this book is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the Design Science License for more details. Available in its entirety as part of the Open Book Project collection at: www.ibiblio.org/obp/electricCircuits PRINTING HISTORY • First Edition: Printed in June of 2000. Plain-ASCII illustrations for universal computer readability. • Second Edition: Printed in September of 2000. Illustrations reworked in standard graphic (eps and jpeg) format. Source files translated to Texinfo format for easy online and printed publication. • Third Edition: Printed in February 2001. Source files translated to SubML format. SubML is a simple markup language designed to easily convert to other markups like A LTEX, HTML, or DocBook using nothing but search-and-replace substitutions. • Fourth Edition: Printed in March 2002. Additions...
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...CHAPTER 1 INTRODUCTION TO INFORMATION TECHNOLOGY 1.1 Introduction Modern civilization has become so complicated and sophisticated that to survive one has to be competitive. This compels people to keep themselves informed of all types of happening in the society. And this in turn entails the need for an infrastructure of information. This is the point where information technology or IT becomes most important, as it is the infrastructure that allows us to get information accurately and in time. Before we define information technology, it is important to understand the notion of Data, Information, Technology, and Knowledge. In everyday conversation, people use the terms data and information interchangeably. However, some computer professional make a distinction between the two terms. Data It is the words, numbers, letters, symbol, sound, video and graphics that describe people, events, things and ideas. It is raw facts about people, objects, and events that have little or no meaning. It is the raw material used to create useful information. It becomes information when you use it as the basis for initiating some action or for making a decision. Information It is defined as the words, numbers, letters, symbol, sound, video and graphics used as the basis for human action or decisions. It is data that have been processed and presented in a form suitable for human interpretation, often with the purpose of revealing trends or patterns that can be used in decision-making. It is data...
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...American International University-Bangladesh (AIUB) 3,4 Student, Department of EEE, Chittagong University of Engineering & Technology (CUET) 2 Abstract- This paper advocates the operation of a toy car that is controlled by a mobile phone that makes a call to the mobile phone attached to the car. In the course of a call, if any button is pressed, a tone corresponding to the button pressed is heard at the other end of the call. This tone is called DTMF (dual-tonemultiple- frequency).The car perceives this DTMF tone with the help of the phone stacked in the car. The received tone is processed by the (ATmega16) microcontroller with the help of DTMF decoder MT887o. The decoder decodes the DTMF tone into its equivalent binary digit and this binary number is sent to the microcontroller. The microcontroller is programmed to take a decision for any given input and outputs its decision to motor drivers in order to drive the motors in forward direction or backward direction or left and right direction. The mobile phone that makes a call to mobile phone stacked in the car act as a remote. For that reason this paper does not require the construction of receiver and transmitter units. I. INTRODUCTION D ual-tone multi-frequency (DTMF) signaling is used for telecommunication signaling over analog telephone lines in the voice- frequency band between telephone handsets and other communications devices and the switching center [1]. The version of DTMF used for telephone...
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...are 11 (The Truth Table of NAND gate is shown in Table.1.1) X(Input) Y(Input) F(Output) 0 0 1 0 1 1 1 0 1 1 1 0 Table 1.1 Truth Table for NAND Gate Q.2 What is the binary equivalent of the decimal number 368 (A) 101110000 (B) 110110000 (C) 111010000 (D) 111100000 Ans: A The Binary equivalent of the Decimal number 368 is 101110000 (Conversion from Decimal number to Binary number is given in Table 1.2) 368 184 --- 0 92 --- 0 46 --- 0 23 --- 0 11 --- 1 5 --- 1 2 --- 1 1 --- 0 0 --- 1 Table 1.2 Conversion from Decimal number to Binary number 2 2 2 2 2 2 2 2 2 1 DE09 Q.3 The decimal equivalent of hex number 1A53 is (A) 6793 (B) 6739 (C) 6973 (D) 6379 DIGITALS ELECTRONICS Ans: B The decimal equivalent of Hex Number 1A53 is 6739 (Conversion from Hex Number to Decimal Number is given below) 1 A 5 3 Hexadecimal 16³ 16² 16¹ 16° Weights (1A53)16 = (1X16³) + (10 X 16²) + (5 X 16¹) + (3 X 16º) = 4096 + 2560 + 80 + 3 = 6739 Q.4 (734)8 = ( )16 (A) C 1 D (C) 1 C D Ans: D (734)8 = (1 D C)16 0001 │ 1101 │ 1100 1 D C (B) D C 1 (D) 1 D C Q.5 The simplification of the Boolean expression ABC + A BC is (A) 0 (B) 1 (C) A (D) BC Ans: B ( )( ) The Boolean expression is ABC + A BC is equivalent to 1 = (A+ A )(B+ B )(C+ C ) = 1X1X1 = 1 Q.6 The number of control lines for a 8 – to – 1 multiplexer is (A) 2 (B) 3 (C) 4 (D) 5 (ABC )+ (ABC ) = A + B + C + A + B + C = A + B + C + A + B + C ( ) ( ) Ans: B The number of control lines for an 8 to 1 Multiplexer is 3 (The control...
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...multiplexers - Verification of the circuit behavior with a CAD tool 2. Problem description Design the synchronous 4-bit counter which outputs follow the predetermined repeated sequence of states. The sequence of states represents the sequence of decimal digits of your ID number with the following exceptions: (1) digits which appear more than ones have to be deleted; (2) digit 9 has to be added at the end of the sequence if your ID has no 9. For example, for ID number 105123456 the second 1 and 5 are deleted and 9 is added at the end resulting in sequence 10523469. In the binary form the sequence is shown in Figure 1. The initial state is not critical. State 9 should be decoded to generate special signal SYNC shown in denominator in Figure 1. In the prelab: the circuit behavior has to be verified in OrCAD. The maximum clock frequency has to be calculated using timing specs of the flip-flops and multiplexers (logical gates) from datasheet. In the experiment: first, the functionality of the counter has to be tested with a pushbutton that controls the clock and a 7-segment LED display connected to the outputs. Finally, the counter sequence should be demonstrated with the logic analyzer synchronized with SYNC signal, 4inputs of the logic analyzer should be grouped into a bus. 3. Approaches Outputs of four D-flip-flops Q3Q2Q1Q0 serve as outputs of the counter. Next states Q*3Q*2Q*1Q*0 are formed from present states Q3Q2Q1Q0 with combinational excitation circuits. By design we understand determination...
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...questions. 1/ What is latch up? Latch-up pertains to a failure mechanism wherein a parasitic thyristor (such as a parasitic silicon controlled rectifier, or SCR) is inadvertently created within a circuit, causing a high amount of current to continuously flow through it once it is accidentally triggered or turned on. Depending on the circuits involved, the amount of current flow produced by this mechanism can be large enough to result in permanent destruction of the device due to electrical overstress (EOS) 2)Why is NAND gate preferred over NOR gate for fabrication? NAND is a better gate for design than NOR because at the transistor level the mobility of electrons is normally three times that of holes compared to NOR and thus the NAND is a faster gate. Additionally, the gate-leakage in NAND structures is much lower. If you consider t_phl and t_plh delays you will find that it is more symmetric in case of NAND ( the delay profile), but for NOR, one delay is much higher than the other(obviously t_plh is higher since the higher resistance p mos's are in series connection which again increases the resistance). 3)What is Noise Margin? Explain the procedure to determine Noise Margin The minimum amount of noise that can be allowed on the input stage for which the output will not be effected. 4)Explain sizing of the inverter? In order to drive the desired load capacitance we have to increase the size (width) of the inverters to get an optimized performance. 5) How do you size NMOS and...
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...1 2 Acknowledgements p.1 tr ©iStockphoto.com/Dennys Bisogno, etc t = top, b = bottom, l = left, r = right, c = centre Computer hardware and software brand names mentioned in this book are protected by their respective trademarks and are acknowledged. Scratch is developed by the Lifelong Kindergarten Group at the MIT Media Lab. See http://scratch.mit.edu Every effort has been made to trace all copyright holders, but if any have been inadvertently overlooked the publishers will be pleased to make the necessary arrangements at the first opportunity. Although every effort has been made to ensure that website addresses are correct at time of going to press, Hodder Education cannot be held responsible for the content of any website mentioned in this book. It is sometimes possible to find a relocated web page by typing in the address of the home page for a website in the URL window of your browser. Photo credits p.1 © peno – Fotolia; p.15 © Dmitrydesigner/Fotolia; p.16 ©iStockphoto.com/Karl Yamashita; p.57 © Romanchuck – Fotolia; p.58 t © C Squared Studios/Photodisc/Getty Images, m ©Dmitriy Melnikov - Fotolia.com, b © Popova Olga/Fotolia; p.59 © picsfive – Fotolia; p.65 © Manfred Schmidt – Fotolia.com; p.67 © dja65 – Fotolia; p.68 © Konstantin Shevtsov – Fotolia; p.69 t © Miguel Navarro/Stone/Getty Images, b © Piero Cruciatti/Alamy; p.73 © Jamdesign/Fotolia; p.78 and 79 © adisa – Fotolia; p.81 © Mykola Mazuryk – Fotolia; p.82 t © Mauro Rodrigues/Fotolia...
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...generates a set of discrete information outputs. Binary numbers are made of binary digits (bits): Discrete Inputs Discrete Information Processing System Discrete Outputs System State Data Types The data types stored in digital computers may be classified as being one of the following categories: 1. 2. 3. numbers used in arithmetic computations, letters of the alphabet used in data processing, and other discrete symbols used for specific purposes. All types of data are represented in computers in binarycoded form. Numbers in Different Bases Good idea to memorize! Decimal (Base 10) 00 01 02 03 04 05 06 07 08 09 10 11 12 13 14 15 16 Binary (Base 2) 00000 00001 00010 00011 00100 00101 00110 00111 01000 01001 01010 01011 01100 01101 01110 01111 10000 Octal (Base 8) 00 01 02 03 04 05 06 07 10 11 12 13 14 15 16 17 20 Hexadecimal (Base 16) 00 01 02 03 04 05 06 07 08 09 0A 0B 0C 0D 0E 0F 10 Summary Decimal Numbers The position of each digit in a weighted number system is assigned a weight based on the base or radix of the system. The radix of decimal numbers is ten, because only ten symbols (0 through 9) are used to represent any number. The column weights of decimal numbers are powers of ten that increase from right to left beginning with 100 =1: …105 104 103 102 101 100. For fractional decimal numbers, the column weights are negative powers of ten that decrease from left to right: 102 101 100. 10-1 10-2 10-3 10-4 … Summary Decimal Numbers Decimal numbers...
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