Bl touch "already triggered at the start of the probing move''

GrahamExp

As the heading says I am getting an error when I try to home Z. The probe deploys and then retracts immediately and gives the error. It was working perfectly well yesterday and I have not changed any settings for the BL touch. No idea where how to solve this.
My config.g
; Z-Probe
M950 S0 C"io7.out" ; create servo pin 0 for BLTouch
M558 P9 C"^io7.in" H5 F360 T6000 A1 B0.2 ; set Z probe type to bltouch and the dive height + speeds
G31 P500 X-71 Y-42 Z3.0632 ; set Z probe trigger value, offset and trigger height
M557 X15:215 Y15:195 S40 ; define mesh grid

Stephen6309

@grahamexp Try putting a ! infront of the ^io7.in. That inverts the pin.
https://duet3d.dozuki.com/Wiki/Gcode#Section_M950_Create_heater_fan_spindle_or_GPIO_servo_pin

GrahamExp

@stephen6309 I have been printing with the setting as is for a week no issues. Suddenly today its not working.

Stephen6309

@grahamexp Verify the crimps on the connector at IO7 for the BLTouch are still good, same with the connector on the BLTouch. I've had them fail when I removed them fome the pin header.

GrahamExp

@stephen6309 so now I have a disaster. tried the ! and instead of stopping the bed jammed up against the nozzle. Problem with moving it back is that it is a core xy setup using a worm wheel drive for the z axis so manually moving the bed down is not an option. On restart the entire homing function is jammed and I cant move Z until its homed

Stephen6309

@grahamexp Send a G92 Z0, and then then you should be able to move Z.

GrahamExp

@stephen6309 yup that worked

GrahamExp

@grahamexp checked the wires all connected just fine. if i run probe deploy macro it works. retract macro works, self test works.

GrahamExp

@grahamexp last time I had a similar problem the pin was bent, checked that also. Not the issue this time.

GrahamExp

@grahamexp on the dashboard the Z probe status is highlighted pink and reads 1000 that was a 0 before when it was working correctly.

Stephen6309

@grahamexp Remove the ! from the io7.in, if you put that in there. Sounds like the BLTouch's endstop connection isn't working as expected.

Here's my Z prode section of config.g, for my Duet 3 6HC w/Pi4 nad 1LC. The BLTouch is on the 1LC.
M950 S0 C"121.io0.out" ; create servo pin 0 for BLTouch
M558 P9 C"^121.io0.in" H10 F120 T6000 ; set Z probe type to bltouch and the dive height + speeds

GrahamExp

@stephen6309 I removed the ! after the failed attempt already. Yesterday I had asked for help moving the one pin from the 26 pin connector. There was a suggestion that I simply unplug it as the second ground was not needed. I did this and it worked for the next Z homing. I suspect that the advice was not correct and may ne teh cause of my current problem. I have put the black wire back on pin 6 (ground) as it was in the hope that would correct the issue but it did not.

Stephen6309

@grahamexp I used the wiring at https://duet3d.dozuki.com/Wiki/Connecting_a_Z_probe#Section_Duet_Num_3. Both grounds are connected together to the connectors ground. (I07 GND)

GrahamExp

@stephen6309 yea I think I am also going to follow that approach. ''BL touch and Rasberry Pi at the same time?'' was the help from yesterday.

GrahamExp

@grahamexp is there a way to reset the BL touch and see if that doesn't fix this

Marshal

@grahamexp try a

M280 Pxxx S160

or

M280 Pxxx S60

I changed my retractprobe.g to

M280 P10 S90
G4 P200
M280 P10 S160

yesterday due to issues with a 3DTouch

Phaedrux

The BLTouch has a command to clear and faults and reset the pin, but that's the same as powering it on.

The original error of it saying it's triggered at the start of the move means it was picking up the triggered signal on the white wire. So either there is a problem with the wiring on the white wire, or it's picking up some interference.

I'm not sure why they include two ground wires on the BLtouch, but I figure it must have been for a reason, so I connect both.

nmsmith89

@stephen6309 said in Bl touch "already triggered at the start of the probing move'':

Here's my Z prode section of config.g, for my Duet 3 6HC w/Pi4 nad 1LC. The BLTouch is on the 1LC.
M950 S0 C"121.io0.out" ; create servo pin 0 for BLTouch
M558 P9 C"^121.io0.in" H10 F120 T6000 ; set Z probe type to bltouch and the dive height + speeds

I have pretty much the same setup except with a Mini 5+ and the BLTouch is constantly going into error mode when probing. Aside from doing what @Marshal did to cancel the error every time I'm out of ideas. My config is the same and the wiring looks right. IDK! Maybe it's the Toolboard1LC. I did notice that my BLTouch is mounted at a very slight angle (maybe 5 degrees) but I wouldn't think that would cause a problem since it's stable.

dc42

@grahamexp said in Bl touch "already triggered at the start of the probing move'':

As the heading says I am getting an error when I try to home Z. The probe deploys and then retracts immediately and gives the error. It was working perfectly well yesterday and I have not changed any settings for the BL touch. No idea where how to solve this.

If you haven't changed anything, then most likely the white wire connected to io7.in isn't making good contact.

You should not enable the pullup resistor on io7.in because it already has a permanent pullup resistor, and enabling the internal one as well reduces the noise margin.

GrahamExp

@dc42 Thanks for the additional info. Ok so how do I disable the internal pullup resistor? I have checked the white wire for a loose connection, cant find one. Resistance across the wire lead is same as the other pins when I check with my meter (1.6 ohms for white, brown, orange and yellow).