When using three variables, the operation is performed on two at a time as shown below:
X⊕Y⊕Z=(X⊕Y)⊕Z
“XOR” is commonly used to check if there is an odd or even number of “1”s. This check is
called “parity”. Odd parity is when there are odd numbers of “1”s and even parity is when
there are an even number of “1”s. Parity check is used for single bit error detection. XNOR (also called “equality coincidence” or “exclusive nor”) X⊕Y=X..Y+X.Y.
“XNOR” Truth Table
X Y (^) X⊕Y
0 0 1
0 1 0
1 0 0
1 1 1
When using three variables, operation is perform on two at a time as shown below:
X⊕Y⊕Z=(X⊕Y)⊕Z^
XNOR is not commonly available as a standard stand alone chip.