Speed Key Name: xor
Signals
Digital inputs: <i1> through <i999>
Digital output: <out>
Description
The Exclusive OR symbol drives its output signal high if the number of inputs that are high is odd, and low otherwise (including all inputs being low).
The Exclusive OR symbol can be expressed using a truth table, where low stands for logical 0 (false), and high stands for logical 1 (true). Thus the truth table for a two-input Exclusive OR has <out> = high only for the rows where exclusively <i1> = high or <i2> = high, but not both. The truth table for a three-input Exclusive OR has <out> = high only for the rows where there are an odd number of high inputs.
Truth table for a two-input Exclusive OR:
|
<i1> <i2> |
<out> |
|
low low |
low |
|
low high |
high |
|
high low |
high |
|
high high |
low |
Truth table for a three-input Exclusive OR:
|
<i1> <i2> <i3> |
<out> |
|
low low low |
low |
|
low high low |
high |
|
high low low |
high |
|
high high low |
low |
|
low low high |
high |
|
low high high |
low |
|
high low high |
low |
|
high high high |
high |
See also Exclusive NOR