mesa 7i76E+7i85S+ linear encoder st1278 heidenhain

Unfortunately homing to index is actually handled very differently from probing a switch. it actually still involves a switch probe. But this is to get you with one rotation of the position where the index needs to be sensed. After that the actual detection of the index is done by the hardware encoder counter, and it resets it's count to zero (or the encoder's home offset) when it senses the index. Linuxcnc doesn't actually "see" the index pulse. Then the "new" encoder count and therefore the position of where the index pulse was, is reported back to Linuxcnc at the next servo thread reading cycle .

I think its possible to do this with a custom component that's similar to the example.
Basically the component would set the probe output pin on index detection in the moving
towards the probe direction, and clear the probe pin on index detection when backing up.
(index detected by setting index enable and detecting the falling edge of index enable)


On the other hand you could try my method without needed any custom components
(though it does require wiring all encoder signals) If you use this method, it can still be
referenced to index by "homing" once at start-up

Hello
I used the hal component from the example I posted earlier.
I have only one problem, when homing the X axis, the switch sets home-sw-in TRUE and further the component supports homing. With the tool length sensor I don't have any limit switch that would set the probe-in to TRUE. If I enter "halcmd sets probe-in True" in the terminal then I can base it without any problems. Therefore, I have a question whether G38.xx can somehow be associated with the "probe-in TRUE" setting. I have two options:
measurement via a button on the desktop,
measurement through REMAP M6,
each option uses a separate .ngc file.
If it were possible to combine the "probe-in TRUE" parameter setting with G38.3 G38.4 it would solve the problem. Can it be done at all?

Thank you for your interest

As for connecting the probe to linuxcnc, I have a / -a, b / -b, with / -z, everything works.

If you have all the encoder pins connected why not try the way I suggested
since it does not require any new components, just existing components:

encoder position --> compare component --> probe signal

This might need more thought, but....

Set the index-enable of the sensor encoder, probe till it goes false.
Read the encoder value to determine the over-travel.
Make an axis move of that length.
Then set the offset.