The unary bitwise operator is ~.
One's complement: ~<operand>
The ~ operator evaluates the one's complement of the operand.
The operand can be any expression evaluating to an absolute expression.
See the following listing for an example of the unary bitwise operator.
~$C ; = $FFFFFFF3 (~%00000000 00000000 00000000 00001100 =%11111111 11111111 11111111 11110011)