Probe does not work with 2.02a + DWC 2.0.0 RC3
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My guess is that the output of your capacitive sensor isn't pulling the E0 endstop input low enough to trigger the probe reliably. The processor's internal pullup resistor is enabled for the endstop inputs in 2.02, and possibly it wasn't in RC2.
Is the output of the capacitive sensor connected to the E0- input directly, or though a diode? If it is through a diode, is it a Schottky diode? Some users have found that only Schottky diodes work with their NPN-output sensors.
It may be better to connect the probe output to the IN pin of the Z probe connector instead of the E0 endstop input, and to use P5 in the M558 command. That will give a slightly higher trigger threshold.
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It's connected using one of these diodes:
https://www.amazon.de/gp/product/B01COV7LCC/ref=oh_aui_search_asin_title?ie=UTF8&psc=1I will try using the z probe connector input. Will I have to change anything but the M558 after doing so?
Btw: It worked with all previous firmware versions.
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@garv3 said in Probe does not work with 2.02a + DWC 2.0.0 RC3:
It's connected using one of these diodes:
https://www.amazon.de/gp/product/B01COV7LCC/ref=oh_aui_search_asin_title?ie=UTF8&psc=1I will try using the z probe connector input. Will I have to change anything but the M558 after doing so?
Btw: It worked with all previous firmware versions.
That's not a Schottky diode, so I think my hypothesis was correct. Using a BAT43 or BAT85 diode instead of the 1N4148 would probably fix it.
You don't need to change anything other than the M558 command if you use the Z probe connector instead. There is a chance that the sensor may have too much leakage and show as permanently triggered, but it's unlikely.
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@dc42 said in Probe does not work with 2.02a + DWC 2.0.0 RC3:
That's not a Schottky diode, so I think my hypothesis was correct. Using a BAT43 or BAT85 diode instead of the 1N4148 would probably fix it.
But why does it work with all other FW versions?
Using the z probe connector does not change anything.
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Can you confirm that when you use M558 P5 (or P8), if you connect the Z probe In pin to ground it makes the Z probe reading change for 0 to 1000? Similarly if you use M558 P4 and connect the E0 endstop STP pin to ground.
The difference between firmware versions is because on some firmware versions, the pullup resistors were not enabled on the endstop inputs. Enabling them improves noise immunity in the high state, but worsens it in the low state. It's arguable which is better.
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Yes, when I short z probe IN and z probe GND, the value changes to 1000.
Wouldn't it be possible to allow us to (de)activate the pullup resistors for individual ports in config.g?
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Wouldn't this be a solution?
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@garv3 said in Probe does not work with 2.02a + DWC 2.0.0 RC3:
Wouldn't this be a solution?
Maybe, but it's an an extra complication. Had you used a Schottky diode as we recommend, or alternatively no diode at all if your Duet is revision 1.04. then it would work anyway.
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It is revision 1.03
I will try to get the diode and test ist. -
I have it on my list to check the noise margin of the endstop inputs with and without the pull up resistor enabled, to see which is better overall.
