More confusion. If you set the commandbyte to a constant, you wont be able to increment or decrement because the control byte is always set for one or the other. Therefore, shouldnt the commandbyte be sent at the same time the data is sent?

Example if the pot is currently sitting at position 200 and the commandbyte is %00000101 and you send:

PORTB.1=0 'ChipSelect
ShiftOut PORTB.3, PORTB.2, 1, [$00,$128]
PORTB.1=1 'ChipSelect


Nothing will happen because the pot is set to only increment.


OR am I getting this completely wrong and the $00 is the commandbyte? This would put 00 at the increment/decrement bits which is a READ condition, therefore any value sent after the $00 would be placed on the pot.
If that is the case, there is no need for the commandbyte constant.