This block performs a logical exclusive OR operation. This means that when either of the connected inputs (I1) and (I2) but not both, are on, the output (Q) is on.
Each input I1 and I2 can be connected to more than one digital input. The logic operation will be done on these too, but when more than one input is connected the OR operation is performed on it, and then the result is input to the exclusive OR block. Therefore two inputs can be on for one input and will still activate Q as the exclusive OR block only sees it as one active input.
Logical exclusive OR operation with two inputs using a truth table.