support for analog touch probes

boelle

Hi

I wonder if it would be to much trouble supporting touch probes with analog output?

https://miscsolutions.wordpress.com/mini-height-sensor-board/<br/><br/>it has an 4 level analog output

i assume that the 4 level output could be used to make for more precise probing.. ie slow down as it gets closer to bed

Repetier

Yes, it is difficult. Analog measurement is optimized for temperature control and stable results (by using averages and outsourcing probably wrong values) not for fast querying needed for z-probes. Therefore only digital endstops are supported.

boelle

well with 4 levels output it does not have to be fast. once it hits the 1st level change speed is reduced some and that reduced the need for fast querying even more :-P

but well at least it makes the purchase simpler

leadinglights

Can a recovery time be added to the Z probe part of the firmware? The significance of this is that some Z probes such as piezo disk probes are triggered by the deceleration after an X or Y move and before the probe downward move. A short time, typically 200ms between the XY move and the start of probe down would correct this.

Thanks,
Mike

Repetier

You can add a script like
#define Z_PROBE_RUN_AFTER_EVERY_PROBE "G4 P200"
to wait 200ms but that is after it was triggered and it might be still in triggering state from the position.

Alternatively make it start so high that going down takes the needed 200ms.

leadinglights

Starting higher makes no difference as the software starts looking for the probe contact immediately at the end of the X or Y movement. The usual symptom is that the firmware reports that the Z probe was triggered before probing. I think what I am asking for is something like
#define Z_PROBE_RUN_BEFORE_EVERY_PROBE "G4 P200"

Thanks,
Mike