Z Probe Switch not inverting after last firmware upgrade



  • Hi, I have an issue after I upgraded my Duet 3 this morning. I'm using the Duet 3 board with R-pi combo in CNC mode and I used " sudo apt update "
    " sudo apt upgrade " connected to the Rpi with Putty. The upgrade went fine with no errors. After the upgrade the Z-Probe in the Duet Web Control 3.1.1 reads 1000 when not triggered and 0 when triggered. My Z probe is just a simple CNC probe which triggers when the tool touches the aluminum block. For endstops I'm using motor stall for homing and it works perfectly. The probe is connected to IO3 on the Duet 3 board. It was working perfectly until yesterday before the firmware upgrade. Below is my endstops and probe settings from the config.g file:
    ; Endstops
    M574 X2 Y2 S3 ; configure sensorless endstop for high end on X and Y
    M574 Z2 S3 ; configure sensorless endstop for high end on Z

    ; Z-Probe
    M558 P5 I1 C"io3.in" H2 F300 T2000 ; set Z probe type to switch and the dive height + speeds I1
    G31 P500 X0 Y0 Z0 ; set Z probe trigger value, offset and trigger height
    M557 X5:500 Y5:500 S50 ; define mesh grid

    Changing the invert parameter I1 to I0 and back doesn't work anymore and it's not recognized from the firmware - see below the console output when sending M558 with both parameters:

    5/23/2020, 10:57:24 AM M558 I1
    Z Probe 0: type 5, input pin io3.in, output pin nil, dive height 2.0mm, probe speed 300mm/min, travel speed 2000mm/min, recovery time 0.00 sec, heaters normal, max taps 1, max diff 0.03

    5/23/2020, 10:58:43 AM M558 I0
    Z Probe 0: type 5, input pin io3.in, output pin nil, dive height 2.0mm, probe speed 300mm/min, travel speed 2000mm/min, recovery time 0.00 sec, heaters normal, max taps 1, max diff 0.03

    and the console output after changing the parameter I0 I1 in the config file and sending M119:

    with I1:
    M119
    Endstops - X: not stopped, Y: not stopped, Z: not stopped, Z probe: at min stop

    with I0:
    5/23/2020, 11:02:15 AM M119
    Endstops - X: not stopped, Y: not stopped, Z: not stopped, Z probe: at min stop

    I did change the parameter maybe 30 times, restarting the board and the whole system every time with no luck. I believe this is a firmware problem because it happened after the upgrade I did this morning. Please advice how to solve this weird issue.



  • You don't use the "I" parameter to invert an input pin anymore.
    Please put an ! before the pin number.
    e.g. "!io3.in"



  • Thank you, problem solved, but it was really unexpected.....


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