Swappable channel A/C for HBP/Fan

[makerbot]

Add an eeprom configuration byte to assign HBP and fan mosfet channels.

[zaggo]

Is this really necessary? Sounds to me like more complicating things than making it easier.

[makerbot]

I've had some requests for it, and it's invisible to users who don't need it, but you're right that it's a low priority issue. Marking it as such. It's simple enough that it will probably happen in v2.1, though.

[zaggo]

true, the internal implementation is (kind of) transparent to the user.
However, I think it is clearer to the operator to read (in a hypothetical "user manual") something like "connect the HBP to the A+A- connectors" than "connect the HBP to A+A- or C+C- (but not B+B-!) and then configure the channel used to control the HBP in the EEPROM settings".
It's easy enough to re-connect the HBP cables to a (the!) well-defined connector.
It's a whole different thing with the axis swapping preferences of the stepper motors. We have preassembled connectors there, which only fit into the sockets in one direction (without using force), so it makes sense to let the users connect the connectors as provided and do the switch in software.
But in this case it's unclear to the user why only the A/C channels are swappable.
A logic solution would be a complete free routing of all channels (A/B/C) to their logic function in software. But again, this would make the code more complicated and thus harder to support.
As long as the A/B/C channels are connected with the current terminals (and not some pre-assembled, fixed connector), I think it make no sense to do a (partial!) channel re-routing in the firmware.