BLTouch Not Working After Firmware Update to 3.4

AlecSanchez

Right before G30

Phaedrux

Try adding a M400 between, like this.

G1 X Y positioning move
M400
M401
M400
G30

AlecSanchez

; homez.g
; called to home the Z axis
;
; generated by RepRapFirmware Configuration Tool v3.3.10 on Wed Apr 06 2022 16:00:08 GMT-0700 (Pacific Daylight Time)
;G90               ; relative positioning
;G1 Z5 F6000    ; lift Z relative to current position
G90
M401
G1 X222 Y500 F6000 ; go to first probe point
G30
;G1 H1 Z-305 F1800 ; move Z down until the endstop is triggered
;G92 Z0            ; set Z position to axis minimum (you may want to adjust this)

; Uncomment the following lines to lift Z after probing
G91              ; relative positioning
G1 Z5 F100       ; lift Z relative to current position
G90              ; absolute positioning

I added it here now and it did deploy, but it did not retract after I triggered it with my finger. However it did stop the bed. M401/M402 commands did not work after this

AlecSanchez

@phaedrux The M400 commands did not appear to work, bltouch did not deploy

Phaedrux

Does M401 and M402 work manually and repeatedly when the print head is in the probing position? Perhaps it's a loose cable when in certain locations.

AlecSanchez

@Phaedrux I found something interesting about this situation, sorry for the late reply. So if the y axis is homed and the y endstop is triggered, the probe will deploy and retract normally. 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. Very odd

Phaedrux

What relation does your Y axis endstop wiring have with the BLtouch wiring? Are they co-located possibly causing interference? Or a short?

AlecSanchez

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

Phaedrux

Just for fun, can you move the Y endstop to another input further away?

AlecSanchez

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

Phaedrux

What kind of endstop is it?

AlecSanchez

Just a normal microswitch

infiniteloop

@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?

AlecSanchez

@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

infiniteloop

@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?

AlecSanchez

@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

AlecSanchez

@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.

Phaedrux

Would you be able to test in standalone mode?

infiniteloop

@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?

AlecSanchez

@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