CODESYS SoftMotion: Command position rollover for modulo axes

With a SoftMotion axis configured as "modulo", it had been observed in a variety of cases that the position command value is failing to rollover at the defined modulo.

For example, with MC_CamIn (see attached for cam definition):

The consequence of this is that for sufficiently large commanded position, the axis stops:

MC_GearInPos and MC_MoveRelative behave similarly.

Am I missing something in the setup?

Test axis: IndraDrive, MPB-20 firmware. CODESYS SoftMotion 4.10.0.0. ctrlX CODESYS Softmotion Adapter 1.10.0.3.

Best reply by eschwellinger

First of all, my preference would be to set the max. travel range to 2^31-1. This is how SoftMotion expect drives to behave.

dwBusModuloMask is an internal variable, so I would not recommend to set it.

The thing with the max. travel-range and the absolute mode of the drive would be an important info for the commissioning guide.

https://www.boschrexroth.com/documents/12605/30723711/CODESYS+SoftMotion+%26+IndraDrive+%E2%80%93+EtherCAT+CoE/df9fb2ea-4108-04a4-aee3-140af1dcc3ad

Instead of using the internal variable dwBusModuloMask I would recommend to use:

SMC_SetBusBandWidth

But as I said... usually this should not be needed.

View original

mc_camin_definition.png

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mc_gearinpos_rollover_1.png

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mc_moverelative_rollover_1.png

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4 replies