@openhardwarecoza : Thanks Peter! I'll take a look at this later this week. There's quite a lot to digest.

@openhardwarecoza looks like you let some of your editor's temporary files get added to this patchset (e.g., Makefile~) you'll probably want to remove those to help @chamnit in the review process.

Oh gosh, sorry you are right @tmpvar!

PS: Prototype boards should be in in about two weeks. (https://openhardwarecoza.wordpress.com/2015/11/29/raspberry-pi-zero-grbl-tmc2660-controller-update/) Hold off until merging in.

I may have pulled the PR trigger too quickly (:
I am going to add some more #ifdefs so it doesnt screw up any default settings. I dont think I did (i have ifdefs for all the pin swaps, pwm register changes (moved spindle pwm to D9) and removal of the control port. But let me just run through it once more.

All the pin swaps, etc have been tested, I just haven't real-world tested the TMC2660s (no hardware on hand to test with yet until those boards come in)

I have one funny bug left on the PWM though. On bootup of grbl (after bootloader - while grbl is already running) the PWM pin is 255. I need to do a M3 S0 in startup gcode and then power on spindle controller. Still bumping my head against that. In my config though I use the Dir as Enable config so I just AND together PWM and Enable. But still, needs to be fixed

Are there any chances of this being implemented at some point? Would be wonderful!