Hardware & Software System

 Logical 1 and 0 are generally represented by voltage level. In a positive logic system, the most Positive voltage system (HIGH) represents the logical 1 status, and the most Negative voltage level (LOW) represents the logical 0 state. In a Negative logic system, the most Positive (HIGH) voltage level represents logical 0 state and the most Negative (LOW) voltage level represents logical 1 state. For example, if the voltage level are -0.1 and -5 V, then in a positive logic system the -5 V level represents a 0 state and the -0.1 level represents a 1 state; in a negative logic system, -0.1 level represents a 0 state and -5 V represents a 1 state. Conversely, if the voltage level are 0.1 V and 5 V, then in a positive logic system the 5 V level represents a 1 state and the 0.1 V represents a 0 state; in a negative logic system, the 0.1 V represents a 1 state and the 5 V level represents a 0 state.                       The effec...

Boolean Addition :- Addition by the Boolean method involves variables having values of either a binary 1 or a 0. The basic rules of Boolean addition are given bellow.                                                                                                    0+0=0                                                        0+1=1                                                        1+0=1                   ...

Logical operation can be expressed and minimized mathematically using the rules, laws, and theorems of Boolean algebra. It is a convenient and systematic method of expressing and analyzing the operation of digital circuit and system. Boolean algebra used binary arithmetic variables which have two distinct symbols 0 and 1. These are called levels or states of logic. For example, a binary 1 represents a High level and a binary 0 represent a Low level.

The logical inverse operation converts the logical 1 to the logical 0 and vice versa. This method is also called the NOT operation. The symbol used for this operation is a bar over the function or the variable. Several notations, such as adding an asterisk, a star, prime, etc. over the variable, are used to indicate the NOT operation. "NOT A" or the complement of A is represented by A bar.