BlTouch on Bootup is retracted.



  • On boot up the BLTouch does its test and stays retracted.

    Question 1:
    Should I put in a command in the config.g to deploy the probe on initial boot up?
    If so, how and where in the confg do I do that.

    Question 2:
    On boot if the bed is too close the BLTouch does the test and blinks and stays retracted. After this you can't deploy the probe. How do you handle this in the config.g? or elsewhere...



  • @chriskimbr
    I use the following code to home using the BLTouch.

    ; homeall.g
    ; called to home all axes
    ;
    ; generated by RepRapFirmware Configuration Tool v2 on Wed Jan 23 2019 13:37:18 GMT-0500 (Eastern Standard Time)

    M280 P64 S160 ; Clear BLTouch Error State
    G91 ; relative positioning
    G1 Z10 F600 S2 ; lift Z relative to current position
    M98 Pdeployprobe.g ; deploy Z probe
    G1 S1 X-205 Y-205 F3600 ; move quickly to X and Y axis endstops and stop there (first pass)
    G1 X5 Y5 F600 ; go back a few mm
    G1 S1 X-205 Y-205 F480 ; move slowly to X and Y axis endstops once more (second pass)
    G90 ; absolute positioning
    G1 X100 Y100 F3600 ; go to first bed center and home Z
    G30 ; home Z by probing the bed
    M98 Pretractprobe.g ; retract Z probe



  • Thanks!.............................



  • What firmware version are you using?



  • @davea I'm trying to put the deploy probe command after it gets back to center of bed right before it probes. I want to do this to avoid hitting the probe on the edge of the bed.

    Is there any way to deploy the probe after it gets to probe point and before it homes(probes) it?

    G1 X180 Y180 F6000 ; go to first bed probe point and home Z



  • @phaedrux 2.02(RTOS) (2018-12-24b1)



  • Have you gone through this probe setup guide? https://duet3d.dozuki.com/Wiki/Test_and_calibrate_the_Z_probe
    And verified that your BLTouch is connected properly? https://duet3d.dozuki.com/Wiki/Connecting_a_Z_probe#Section_BLTouch
    There are some common bltouch troubleshooting steps here https://duet3d.dozuki.com/Wiki/BLTouch_Troubleshooting

    G30 should take care of deploying and retracting the probe. You shouldn't use M98 Pdeployprobe.g because it doesn't allow the duet to keep track of the deployment state of the probe. If you really do need to deploy and retract it manually, you should use M401 and M402.

    If you need to ensure that the probe isn't in an error state and that it's retracted before homing that's fine.



  • @phaedrux why use m401, 402 over m98?



  • @chriskimbr M401 and M402 do basically the same thing as M98, they call the same macro file, but M401 and M402 allow the Duet to keep track of the deployment state of the probe. So it knows if the pin is out or not.

    But you shouldn't need to do either in your homing files, except if you want to ensure the pin is retracted at the start of homing.



  • @phaedrux my deployprobe.g file was named bad. thats why g30 wasn't working.

    its working now and i removed the m98 Pdeployprobe.g and m98 Pretractprobe.g commands.

    the g30 doesn't seem to handle the bltouch if its in error state and blinking. So i put the m98 Presetprobe.g at the beginging in case there is an error. the resetprobe.g contains M280 P3 S160 I1



  • @chriskimbr said in BlTouch on Bootup is retracted.:

    So i put the m98 Presetprobe.g at the beginging in case there is an error. the resetprobe.g contains M280 P3 S160 I1

    May want to add G4 P500 after the command to clear the error to pause for half a second to give the servo time to activate.

    Glad it's working now.


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