Trouble with Using External Stepper Motors



  • So I am using external stepper motors and am taking advantage of the signals that pass through the 50 Pin Connector. However, I designed a PCB that would only take the signals I needed and then pass the signals I do not use back into the Duex. This way I could still use the I2C on the Duex for other purposes and things like the fans and such. The problem I am running into is that the Duex will freak out if you don't send the E2_EN, E3_EN, E4_EN, E5_EN, and E6_EN back into it when I am trying to use those signals to power the Enable on my own external stepper driver. The motors turn just fine when I don't have the Duex connected, only my PCB is connected to the Duet via the 50 pin connector. Any advice on how I can get this working and keep the features of the Duex as well?



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  • administrators

    The Duet is detecting that you have a DueX5 connected and is trying to initialise the drivers on it via SPI. The EN_ signals on the expansion bus become the chip select signals for those drivers.

    Probably the simplest fix is to recompile RepRapFirmware, and change the Platform.cpp file to set numSmartDrivers to 5 regardless of whether a DueX board is detected.



  • @dc42 Yup that was it, I'm just gonna pass through the enable signals through to the stepper drivers on the Duex and set the external stepper drivers to be active low enable.


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