Using a duex5 with expansion board`



  • Is there anything wrong with using the duex5 with an expansion board in line? I do not plan on using the enable pins on the expansion board, and as fat as I can tell, that is the only possible issue with this scheme.

    Any thoughts?



  • Probably should clarify, I would be connecting them using a ribbon cable with 3 connectors.


  • administrators

    You can use a DueX2 plus expansion board (using just the 3 stepper driver outputs on the expansion board that are distinct from the 2 on the DueX2). You can't use a DueX5 + expansion breakout board because the firmware will assume you are using the TMC2660 drivers on the DueX5.

    You can use the 2 sets of stepper driver outputs on the CONN_LCD connector at the same time as a DueX5.



  • @dc42 Ahh, okay, I just ordered some Duex2s, just curious, what components would I need to remove from the Duex5 to make the firmware see it as a duex2? Would it be enough to desolder R66, R4, R19, and R20? (I looked at the do not populate notes in the schematic)

    Thanks,
    Tim


  • administrators

    You should only need to remove or move 1 resistor, the one that sets the signal level on the I2C expander chip that the firmware reads to determine the type of expansion board.

    Unfortunately you would need to remove the 3 stepper drivers too, or cut some traces. Or cut the 3 wires in the ribbon cable that feed the CS/EN signal to the 3 DueX5 drivers that you won't be using, and tie those three wires to +3.3V on the DueX5. Otherwise those stepper drivers will drive the SPI bus when you enable the 3 external drivers. This is because the same MCU pins drive the CS pins of the onboard drivers and the EN outputs of the expansion breakout board.


 

Looks like your connection to Duet3D was lost, please wait while we try to reconnect.