XNOR (Exclusive NOR) is the opposite of XOR (Exclusive OR)
A way to remember XOR is “must have one or the other but not both” XNOR is the opposite so it’s “must have both or none” so both inputs must be 1 or 0.
XNOR or XOR is very common in homes with staircases so that you can turn on and off the light in the staircase regardless of which floor you are on.
If you google staircase switches, you will be told that they mostly use XOR but according to the wiring diagrams they use XNOR.
XNOR (Exclusive NOR) is the opposite of XOR (Exclusive OR)
A way to remember XOR is “must have one or the other but not both” XNOR is the opposite so it’s “must have both or none” so both inputs must be 1 or 0.
XNOR or XOR is very common in homes with staircases so that you can turn on and off the light in the staircase regardless of which floor you are on.
If you google staircase switches, you will be told that they mostly use XOR but according to the wiring diagrams they use XNOR.
Isn’t that the same as AND but with a lot of extra words?
No, AND won’t match 0,0 while XNOR will. An AND switch would be useless for a staircase.
AND also won’t match 1,0 or 0,1 while XOR does.
so AND. Always AND.
My bad. It’s “must have both or none”