G33 does not adjust IPM after the first one. 2.9.0 pre-3376

Which version of LinuxCNC?

This could, potentially be a HAL setup prblem.

But could also be the unwelcome return of github.com/LinuxCNC/linuxcnc/issues/704

So, you are saying that the spindle encoder resets at the start of the G33 move, but the axis still moves at full speed?

Can you confirm that the spindle.0.revs pin is zeroed at the start of the G33 move?

I think that you have broken the position feedback.

If you see the index-enable go high, then low, and the encoder position and counts don't reset to zero then the encoder counter is not working properly.

RBC wrote:

So the revs should be reset every time an index-enable is sent to low. And revs always stay between 0-359 ?

The standard hostmot2 encoder does the right thing.

LinuxCNC sets index-enable high.
hosmot2 (ie, the FPGA code) waits for an index, then sets the encoder counts to zero at the same time as setting index-enable low.
As far as I am aware the counts then just continue to increase until the next index-enable. The HAL driver converts those into a position in complete revolutions.

I am glad that you admitted to the Hostmot2 changes, we could have wasted days looking for a bug in the G33 code.