Specifications

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When used in a program, a logic AND operation is performed by the program instruction,
which will be discussed later. For the time being, it is enough to remember that logic AND in
a program refers to the corresponding bits of two registers.
OR Gate
Similarly to the previous case, OR gates also have two or more inputs and one
output. A logic one (1) will appear on its output if either input (A OR B) is
driven to logic one (1). If all inputs are at logic zero (0), the output will be
driven to logic zero (0).
In a program, logic OR operation is performed between the corresponding registers’ bits- the
same as in logic AND operation.
NOT Gate
This logic gate has only one input and only one output. It operates in an
extremely simple way. When logic zero (0) appears on its input, a logic one (1)
appears on its output and vice versa. This means that this gate inverts the signal
by itself. It is sometimes called inverter.
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