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Modelsim 10.1 problems with Serial Transceivers
In ModelSim 10.1, the TXP and TXN outputs of the serial transceivers do not toggle.
This problem was found on the Virtex-6 GTX, but it exists in the 7 Series GTX, GTP and GTH as well.
This problem will be fixed in the next release of the software, ISE14.1. ISIM or an earlier version of ModelSim can be used as a workaround.
- Virtex-6 LXT