My design fails in MAP with the following placer error. I've checked the polarity of the connections and they are not incorrect. How do I avoid this error?
ERROR:Place:910 - It appears that the specified pin locations for differential
are reversed and can not be placed without changing the functionality
(polarity) of the signal. To correct this error, either modify the LOC values
or change the buffer connections in the code so that the P-side of the
differential buffer is LOCed to the pin location "IOB_X0Y221" and the N-side
of the buffer is LOCed to the pin location "IOB_X0Y220".
This issue is under investigation. Meanwhile, the error can be avoided by setting the following environment variable:
Linux and Solaris:
setenv XIL_PAR_ALLOW_LVDS_LOC_OVERRIDE 1