ID:181048 Cannot add <io_pad_name> to DQS Group fed by <dqs_pad_name>

CAUSE: The Fitter is unable to group the specified I/O into the specified DQ group. This can be caused if an illegal DQ_GROUP assignment is made to I/O. For example, if the netlist connectivity implies that an I/O must be part of a particular DQS Group, but a DQ_GROUP assignment is used to force the I/O into a different DQS group, then this error can result. Additionally, this error might happen if multiple conflicting DQ_GROUP assignments are made to the same I/O.

ACTION: Examine DQ_GROUP assignments and the netlist topology of the specified I/O to eliminate the conflict.