How do the various encoder modules cope with rawcount rollover?
I am thinking specifically in terms of spindle-mounted encoders which
may roll over an s32 in a few hours. It is obviously unlikely that any
axis could rotate in one direction for that long.

I have a HAL component that uses rawcounts and an offset to compute
motor rotor angle to determine the correct phase currents. If
rawcounts rolls over this is likely to go rather wrong. I think that I
might have to watch for it happening, and then recalculate the offset
applied on the basis of modulo arithmetic on the max value of an s32
and the encoder to phase scaling value.
(Or perhaps copy the thread-to-thread rawcounts deltas into an s64 )

-- 
atp
"Torque wrenches are for the obedience of fools and the guidance of wise men"

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