ID:16543 Incompatible pin pair assignment. RX pin < <text> > is assigned to pin location <text>; TX pin < <text> > is assigned to pin location <text>, but the pin locations are not compatible because they are merged through the Assignment Editor into a single duplex channel. To correct the incompatibility, assign the specified RX pin to pin location <text> or remove the pin assignments.

CAUSE: The specified RX and TX pin pairs are assigned to incompatible locations.

ACTION: Change the pin assignments in your design to correct the incompatibility. You can assign the specified RX pin to the suggested pin location to correct the incompatibility, or you can remove the pin assignment.