In the 7 series architectures, it has been found that differential pairs may not be reported correctly in the PAD report from ISE or PlanAhead tools.
The P-side is reported correctly as an input but the N-side is incorrectly reported as an output.
This has been found in PlanAhead tool when targeting a 7 series architectures. This issue only affectsthereporting process and the design is correct.
The issue has been fixed in PlanAhead tool 14.4.