BLTouch Not Working After Firmware Update to 3.4
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What relation does your Y axis endstop wiring have with the BLtouch wiring? Are they co-located possibly causing interference? Or a short?
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y-endstop is on io1, bltouch is on io4. They are right above eachother on the board, but the wires are not run through the same path if that makes sense
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Just for fun, can you move the Y endstop to another input further away?
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Yea I just tried moving it to io2 and it does the same. It does appear the y-endstop is shorting the bltouch somehow, just not sure why
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What kind of endstop is it?
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Just a normal microswitch
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@alecsanchez said in BLTouch Not Working After Firmware Update to 3.4:
I just tried moving it to io2 and it does the same.
Can you home X and Y? Does Duet Web Control indicate these axes as homed?
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@infiniteloop x and y home normally, and duet web control indicates them as homed also. If I send g92 y0 to "home" y, the bltouch works normally. It is only when the y endstop is triggered that something seems to short out
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@alecsanchez said in BLTouch Not Working After Firmware Update to 3.4:
It is only when the y endstop is triggered that something seems to short out
Thank you. How do you power the Duet: over USB?
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@infiniteloop it is powered by a 24v mean well power supply. The raspberry pi 3b is connected via ribbon cable, and that has its own 5v power supply
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@infiniteloop I have performed these additional steps to give more insight:
- switched the x and y endstop pins in the config.g file (so now hardware-wise, the x endstop acts as the y endstop.)
- activating the x endstop displayed the same behavior - the bltouch no longer deployed
- activating the y endstop did not affect the bltouch
This shows that it is not an issue with the wires shorting. Whichever endstop is allocated as the y endstop in the config.g file seems to mess with the bltouch.
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Would you be able to test in standalone mode?
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@alecsanchez Sorry for the many questions - I just try to exclude some variables from the list. At this point, it looks like an electrical (or wiring) problem to me. However, I'm a bit puzzled:
You told @Phaedrux:
But if I home the z axis in a location thats not at y-min, it wont deploy since the y endstop isn't triggered. However if I manually trigger the y endstop while in the process of homing z, the probe will deploy.
… and told me:
It is only when the y endstop is triggered that something seems to short out
Could you please clarify whether the BLTouch works only with activated endstop - or is it just the other way round?
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@infiniteloop Yea I can see how that can be confusing, let me see if i can clarify:
- If I home x and y, and then home z, the bltouch does not deploy. BUT, while the bed is moving up to home z, if I press the y endstop manually with my hand, the bltouch will deploy.
- the bltouch will deploy at any point along the build area UNTIL I manually activate the y endstop. once i press the y endstop, I am no longer able to use m401/402.
- If i switch the pinouts in config.g to use the physical x endstop as the y endstop, and activate the x endstop, the bltouch no longer deploys
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Also to confirm, the bltouch works regularly WHILE activated.
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@alecsanchez said in BLTouch Not Working After Firmware Update to 3.4:
let me see if i can clarify:
That is, if the Y endstop was once pressed (and released), the BLTouch will no longer work, except of when you press and hold the endstop again?
How is the Y endstop wired: two lines from the Duet to the switch, GND and signal?
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@infiniteloop Those are all correct
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@Phaedrux If I can avoid converting to standalone mode that would be great... but if that is a better move forward to test, I can do that. This just very much feels like a possible bug since it occurred immediately after updating
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@alecsanchez OK. I have no idea how the BLTouch is wired, but I think there must be a signal to control the deploy mechanism - and another line needs to be grounded in order for this to work. Maybe the Y endstop is needed to deliver GND? Can you check the voltages on the pins of the BLTouch-connector (on your Duet, BLTouch unplugged): Once with open Y-switch, once when it's closed? Do you get different readings? And please be careful not to shorten anything, this could damage your Duet
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@infiniteloop I would find this plausible, except for the fact that the bltouch deploys properly before activating the Y endstop. This suggests it is wired correctly, right?
I think it is odd that this phenomenon occurs with any switch that is directed to the Y endstop in config.g. It seems that is the more likely issue
