Hi,
With our students, we want, as practical exercise, program our external position controller in ctrlX core PLC without using the drive built-in position controller. So we want our 'home made' position controller be able to give the speed setpoint to the drive and read back the position measurement. We must be able to control a ctrlX drive from the ctrlX Core PLC via AxisInterface.
The aim is to change the Op Mode to mode 1 or mode 2 in order to switch from position mode to velocity Control mode and drive register S-0036 in MDT then read back the velocity via register S-0040 via the AT.
Our question is: is it possible to do this via MB_AxisInterfaceBase?
Please note that we don't want the ModeVel command, which is a speed mode internal to the PLC, we want the drive's "real" Velocity Control mode to drive the speed regulator directly without going through the position regulator!
The second question is what is the simplest method for adding the MDT and AT registers and using them in the PLC via the DataLayer.
Thanks in advance for help
Best Regards
Aldo
When using the CXA_MotionInterface and so the ctrlX MOTION the standard control mode is position controlled lagless and you need to use the ModeVel (with drive vel := true) to switch it. But in both cases the set value will be written by the ctrlX MOTION and so cannot be written via data layer realtime simultaneously. You will have to use the drives without motion only controlled by you via PLC.
For the positioning mode there is a function called axsCyclicSetPointCmd to enable an external position set point. But it is not available for velocity set values.
Adding cyclic data is done via the expert mode in ctrX IO Engineering. See also general ctrlX IO Engineering documentation.
And afterwards add the cyclic data into your PLC Engineering via the realtime data layer node. See also general ctrlX PLC Engineering documentation.
For several information and how tos please refer to our "Collection of how to videos, blogs and examples for ctrlX AUTOMATION".