Honored Contributor
Honored ContributorSo after further investigation, the error seems to occur due to the MSb , HSTC_TX[13].
If I get rid of the pin by assigning it to a constant, the fitter error goes away! , From the RTL view, the proper MUX structure is being inferred, but for some reason the fitter must think that the generated netlist for this output is supposed to be differentially related! Another weird observation, is that the LSb being driven by the signal is always the one in conflict with the fitter. If I were to just tie HSTC_TX[0] to GND, the error would be with HSTC_TX[1]. If I were to tie HSTC_TX[1:0] to GND, the error would be with HSTC_TX[2]. At this point I am extremely confused. EDIT: It has to be netlist related, since if I negate the one bit (HSTC_TX[13]), the error goes away. For some reason the fitter is looking at my logic, assuming that these pins are supposed to be differentially related, and then complaining when the pin out does not assign them to the same differential pair outputs.
