Just to be clear, there is no requirement that stepgens (or analog channels or
encoders or whatever) be used in a particular order or joint/axis mapping, its just less confusing when they are used in the common default order:
Joint0 = X = hardware channel 0
Joint1 = Y = hardware channel 1
That, is there is no reason that you could not us a 7I77 analog channel 4
and encoder channel 1 for the X axis except for the confusion it would cause
What is fixed (in the firmware) is the mapping of stepgens/analog outs to
specific physical pins
