Problematic setPosition behavior for absolute encoders

[kmpeters]

Currently the setPosition behavior changes the position offset:

motorAutomation1/automation1App/src/Automation1MotorAxis.cpp

Line 229 in a83781d

if (Automation1_Command_PositionOffsetSet(pC_->controller_, 1, &axisNo_, 1, &adjustedPosition, 1))

For axes with absolute encoders, it makes more sense to keep the position offset fixed. In this case, the setPosition function would do nothing (and may need to return a status other than success to avoid the target position getting out-of-sync with the readback position).

A database for axes with absolute encoders should be created that would do the following:

1. Set RSTM to 0 (Never) for the motor records
2. Add a record to allow the absolute encoder offset to be set manually from EPICS

[kmpeters]

@GarrettSullivan-Aerotech, how should the driver detect when an axis is using an absolute encoder?

[kmpeters]

It looks like the driver just needs to check the AbsoluteEncoderOption (391) for the AxisStatusItem for each axis.

[rakaerotech]

AxisStatusItem.AbsoluteEncoderOption will return what an axis is capable of, not what is is currently configured for.

I think the best way for this is to check the PrimaryFeedbackType axis parameter and use the PrimaryFeedbackType enum to see if the feedback is configured for one of the various absolute encoder types (EnDat, BiSS, etc.).