CAN-FD connection to a VFD for spindle control

Anon1337

Hi,
I wonder is there a way to connect a VFD for a spindle other than 0-10V PWM? I know there are CANbus enabled VFDs out there like this one for example.
Is this simply a software issue or are there any hardware limitation (noise from the VFD perhaps?) to CAN connected VFDs?

Also anyone with an ATC spindle using the Duet?

jay_s_uk

@Anon1337 there's currently nothing in the firmware for control of a spindle over CAN or CAN-FD.
It would need implementing

I've moved to the firmware wishlist category

Anon1337

@jay_s_uk yeah you are right this might be more of a firmware thing.

So there aren't any hardware limitations to this? I might try to tackle it myself then.

o_lampe

@Anon1337 There's an ongoing discussion about implementing "custom CAN messages" here
I guess that'd fit your usecase, too?

T3P3Tony

@Anon1337 you are correct, no hardware limitations if you use something like a SammyC21 or a custom board that runs RepRapFirmware expansion board firmware, If you can get the board on the CAN-FD bus and support the RRF CAN-Fd protocol then its a firmware job to add spindle support. The custom CAN-Fd message that @o_lampe linked to is one option however I suggest discussing this further with @dc42 on here first because it may make more sense to extend M950 spindle support to handle the case of a CAN-FD connected spindle or use another gcode to configure it thats spindle specific.

o_lampe

@T3P3Tony Such a dedicated gcode for CAN-spindle support probably exists already? If RRF decides to implement it, just make sure it is compatible with CNC-CAD software

T3P3Tony

@o_lampe I would expect the CAM software to use M3 M5 etc, can you point to ant CAN/CAN-FD specific spindle control gcodes?

o_lampe

@T3P3Tony No I'm not aware of it.
I just had a flashback, when RRF in the beginning tried to support laser diodes via M106/M107 commands, instead of the established codes.