The $ZBITOR function performs a bitwise OR on two bit strings, and returns a bit string equal in length to the longer of the two arguments (containing set bits in those positions where either or both of the input strings have set bits). Positions that correspond to positions where neither input string has a set bit have cleared bits in the resulting string.
The format for the $ZBITOR function is:
$ZBITOR(expr1,expr2)
The first expression specifies one of the bit strings that is input to the OR operation.
The second expression specifies the other bit string that is input to the OR operation.