【正文】 169。 Bharati Vidyapeeth’s Institute of Computer Applications and Management, New Delhi63 by Anurag Sharma U1.?? Fundamentals of Information Technology UNIT I 169。 Bharati Vidyapeeth’s Institute of Computer Applications and Management, New Delhi63 by Anurag Sharma U1.. ?? Learning Objectives In this Unit we will discuss : ? Digital Signals and Logic gates ? Number systems: ?Binary, ?octal and hexadecimal number systems, ?signed binary number, ?binary arithmetic, ?2?s plement arithmetic ? Microprocessors: ?Introduction, ?System Bus, ?Architecture and operation of 8085 microprocessor and instruction set 169。 Bharati Vidyapeeth’s Institute of Computer Applications and Management, New Delhi63 by Anurag Sharma U1.. ?? Logic Gates ? Logic gates are electronic circuits that operate on one or more input signals to produce standard output signal ? Are the building blocks of all the circuits in a puter ? Some of the most basic and useful logic gates are AND, OR, NOT, NAND and NOR gates 169。 Bharati Vidyapeeth’s Institute of Computer Applications and Management, New Delhi63 by Anurag Sharma U1.. ?? Logic Gates AND Gate ?Physical realization of logical multiplication (AND) operation ?Generates an output signal of 1 only if all input signals are also 1 169。 Bharati Vidyapeeth’s Institute of Computer Applications and Management, New Delhi63 by Anurag Sharma U1.. ?? Logic Gates AND Gate (Symbol and Truth Table) 169。 Bharati Vidyapeeth’s Institute of Computer Applications and Management, New Delhi63 by Anurag Sharma U1.. ?? Logic Gates OR Gate ?Physical realization of logical addition (OR) operation ?Generates an output signal of 1 if at least one of the input signals is also 1 169。 Bharati Vidyapeeth’s Institute of Computer Applications and Management, New Delhi63 by Anurag Sharma U1.. ?? Logic Gates OR Gate (Symbol and Truth Table) 169。 Bharati Vidyapeeth’s Institute of Computer Applications and Management, New Delhi63 by Anurag Sharma U1.. ?? Logic Gates NOT Gate ?Physical realization of plementation operation ?Generates an output signal, which is the reverse of the input signal 169。 Bharati Vidyapeeth’s Institute of Computer Applications and Management, New Delhi63 by Anurag Sharma U1.. ?? Logic Gates NOT Gate (Symbol and Truth Table) 169。 Bharati Vidyapeeth’s Institute of Computer Applications and Management, New Delhi63 by Anurag Sharma U1.. ?? Logic Gates NAND Gate ?Complemented AND gate ?Generates an output signal of: ?1 if any one of the inputs is a 0 ?0 when all the inputs are 1 169。 Bharati Vidyapeeth’s Institute of Computer Applications and Management, New Delhi63 by Anurag Sharma U1.. ?? Logic Gates NAND Gate 169。 Bharati Vidyapeeth’s Institute of Computer Applications and Management, New Delhi63 by Anurag Sharma U1.. ?? Logic Gates NOR Gate ?Complemented OR gate ?Generates an output signal of: ?1 only when all inputs are 0 ?0 if any one of inputs is a 1 169。 Bharati Vidyapeeth’s Institute of Computer Applications and Management, New Delhi63 by Anurag Sharma U1.. ?? Logic Gates NOR Gate (Symbol and Truth Table) 169。 Bharati Vidyapeeth’s Institute of Computer Applications and Management, New Delhi63 by Anurag Sharma U1.. ?? Logic Gates Logic Circuits ?When logic gates are interconnected to form a gating /logic work, it is known as a binational logic circuit ?The Boolean algebra expression for a given logic circuit can be derived by systematically progressing from input to output on the gates ?The three logic gates (AND, OR, and NOT) are logically plete because any Boolean expression can be realized as a logic circuit using only these three gates 169。 Bharati Vidyapeeth’s Institute of Computer Applications and Management, New Delhi63 by Anurag Sharma U1.. ?? Logic Gates Logic Circuits Example1 for finding Boolean expression of a Logic Circuit 169。 Bharati Vidyapeeth’s Institute of Computer Applications and Management, New Delhi63 by Anurag Sharma U1.. ?? Logic Gates Logic Circuits Example2 for finding Boolean expression of a Logic Circuit 169。 Bharati Vidyapeeth’s Institute of Computer Applications and Management, New Delhi63 by Anurag Sharma U1.. ?? Logic Gates Logic Circuits Example1 for constructing Logic Circuit from a Boolean expression. 169。 Bharati Vidyapeeth’s Institute of Computer Applications and Management, New Delhi63 by Anurag Sharma U1.. ?? Logic Gates Logic Circuits Example2 for constructing Logic Circuit from a Boolean expression. 169。 Bharati Vidyapeeth’s Institute of Computer Applications and Management, New Delhi63 by Anurag Sharma U1.. ?? Logic Gates Universal NAND Gate NAND gate is an universal gate, it is alone sufficient to implement any Boolean expression. 169。 Bharati Vidyapeeth’s Institute of Computer Applications and Management, New Delhi63 by Anurag Sharma U1.. ?? Logic Gates Universal NAND Gate Implementation of NOT Gates by NAND Gates 169。 Bharati Vidyapeeth’s Institute of Computer Applications and Management, New Delhi63 by Anurag Sharma U1.. ?? Logic Gates Universal NAND Gate Implementation of AND Gates by NAND Gates 169。 Bharati Vidyapeeth’s Institute of Computer Applications and Management, New Delhi63 by Anurag Sharma U1.. ?? Logic Gates Universal NAND Gate Implementation of OR Gates by NAND Gates 169。 Bharati Vidyapeeth’s Institute of Computer Applications and Management, New Delhi63 by Anurag Sharma U1.. ?? Logic Gates Method of Implementing a Boolean Expression with Only NAND Gates Step 1: From the given algebraic expression, draw the logic diagram with AND, OR, and NOT gates. Assume that both the normal (A) and plement ( ) inputs are available Step 2: Draw a second logic diagram with the equivalent NAND logic subst