Target Position is in DAC_OUT in CSP mode

Encoder position is in ENCODER in CSP mode.

Both can be monitored on the scope.

FE is DPOS - MPOS so has a larger value than the real following error due to the EtherCAT cycle time.  Set FE_LIMIT to suit the max FE value that might be seen.

If you want the correct following error value then add the Actual Following Error to the PDO and look at DRIVE_FE.  In that case also set DRIVE_FE_LIMIT.