There's an article
It is called: Can Stallguard detect a step loss?
Bernard in response wrote: see the FAQ for the StallGuard drivers
I cannot locate that FAQ.
The question is:
what is the resolution of Stall Guard in TMCM?
With what precision can a TMCM can detect a stall, and how it reports position then?
Suppose we have a TMCM303, or TMCM110.
The questions below assume 64x microstepping.
Actually microstepping would be 16x anyway. TMCM cannot divide step more than 16 times. So, in our example we assume multiples of 4 microsteps for simplicity (64/4=16x microstepping).
But the same question would be valid just for any other microsteppipng as well, including full steps.
Suppose a motor is instructed to move 192 steps.
Suppose a motor hits an obstacle at a position of 160 microsteps
(multiple of 4
With what precision will we know the missed steps? Will TMCM report a position of 160
? Or will it report any other position?
Suppose we instruct TMCM to move the motor in the same direction by 4
microsteps (in 64x this equals one real microstep of 16x). The obstacle is still not removed. Motor does not move. A stall occurs. What position TMCM would report? 164
? Or any other?
What actual phases would be set in the internal TMC246 driver of TMCM?
The phases for the missed step (exerting a force on an obstacle)? Or the phases of the last successful step? Can the microprocesor of TMCM automatically adjust the phases to the last successful step, so that motor does not jump after an obstacle is removed?
What those phases can be? Only full step? Or any microstep?
would help restore or adjust a postion. Case 2.
would help perform homing.
is self explanatory.