M581 M582 M291, What am I doing wrong?

  • I can not understand how M581 M582 and M291 work.

    With a MMU, I have to pull the filament up to one sensor, then to another, and I try to suspend if the first sensor is not reached, by an error message, then a manual intervention, then clicking "ok" would resume the tool change.
    I'm not printing, just testing using macros.

    Here is my code extracted from tpost_all.g:
    G1 V1000 F1000 S1 ; I leave my filament until the sensor
    M581 E1 S1 T2 C0    ; I activate the E1 sensor on the trigger2.g
    M582 T2 ; I test my sensor
    I do other things

    M291 P "Selector sensor" S2 V1

    My problems:

    1. Falling / rising, I do not have a rising or falling edge, I have a sensor that remains in the high state. Whatever I do (S1 or S0) the message appears.
    2. The message appears, but after executing the "I do other things" commands when the tool change macro is finished.

    What am I doing wrong?


  • I forgot to specify that I was in 2.02 last stable
    on Duet 1.04

  • use M581 T2 to check you have configured the trigger correctly. the trigger only needs to be on for one line for it to work, you need to deactivate the trigger straight away as to not interfere with filament M591 sensing.

    are you only running one finda sensor? thats all thats needed. mine is configured M581 V S1 T2 C0

    is the sensor connected to the V axis endstop? and it HAS TO BE on the main duet board for it to function correctly too. make sure you read my notes closely

  • I have not checked M581 T2
    But yes the sensor is on the main board (E1) and I have no filament sensor, not yet.
    But, my axis is on the duex.
    The only thing I do not do is turn off immediately with M581 T2 S-1
    I use a simple microswitch
    But I'm not in print mode

  • The drive needs to be on the duet board not the duex2 as stated above

  • hang on are you using a prusa MMU2 or a custom MMU?

  • A custom

  • @gavatron3000
    The drive is on duex, I will change it

  • ok no worries, if its a custom one it'll be different setup to the prusa version so take my advice lightly as its not the same

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