- fix homing procedure for Idler and Selector
(homing now ends with a move to the Parking position)
- fix unit tests' startup conditions with regard to necessary
homing of Idler and Selector
TODO: still test_cut_filament fails for minor reasons
Should also hopefully fix the random behavior of the DIR pins. When I was testing a really slow timing, the steppers seemed to want to not go in the right direction. That was fixed with the critical section. The 1us delay might be overkill, but I'm not the one that added a 100nF capacitor on the LATCH line (basically chip select). This might be part of the randomness that happened and why some board behaved better than others (stronger GPIO outputs)
I hate when the compiler doesn't check something what it normally does:
`pgm_read_byte` is more than happy with a parameter (*str), which reads
an address at a location where *str points to - which is obviously not the intent.
we shall think about the Pulley as well, it looks like it should get its
own class just like Idler and Selector as it behaves very similarly in terms
of stepping and error checking
TogglePin was incorrectly using the PINx pin for toggling, causing the
current pins (in addition to the requested ones) to be toggled, causing
stepping havoc.
The parameter config::AxisConfig::uSteps was supposed to be
microstepping resolution, but it's instead being used as the driver's
MRES directly.
To avoid a runtime conversion, rename the field to mRes and define a new
enum listing all the possible (and valid) microstepping resolutions.
This simplifies the code and makes clear the stepsPerUnit scale.
Assign correct stepsPerUnit to all axes as a result, including working
limits.