I had thought of using SHIFTRIGHT (>>) to shift the bits off the LSB end of the pattern to turn the
port on or off based on it being a one or zero, but it would appear that SHIFTRIGHT discards the shifted
bit and won't let it be used.
Maybe not the best way, but "pattern" can be the high byte alias of a word variable,
then when you shift it, the low byte will either be 00000000 or 10000000,
which is either zero or not zero.