The internal and external I/O is flexible.  Any axis can use any Input as home, limit switch and feedhold inputs.  While the servo loops must use the on-board analogue outputs for servo drive control, the external ADC input modules may be used for feedback.

External I/O is provided as either CANbus modules (CANIO) or as EtherCAT modules (Flexslice I/O).  Which one to use depends on the selected Motion Coordinator.  MC403 .. MC508 have CANbus ports.  The MC4N and MC6N have CANbus and in addition the MC4N-ECAT and MC6N-ECAT have EtherCAT for both drives and I/O.  The Flex-6 Nano has EtherCAT but no CANbus.

Example axis inputs setup:

BASE(5)
DATUM_IN = 23
FWD_IN = 104
REV_IN = 105
FHOLD_IN = 60