I am using Mentor C.2 Design Architect with Xilinx A2.1i SP5, tageting Virtex-E. How do I use the LVDS differential I/O? I do not see them in the Virtex library.
解决方案
In the Xilinx A2.1i software (with any Service Pack) the LVDS component symbol is not available in the library to put down onto your schematic.
Currently you will have to use a User Constraint File (UCF) in order to use the LVDS I/O standard.
Note: The Xilinx 3.1i software will have these component symbols to put down onto the schematic.
Please see (Xilinx Solution 8187) for more information on LVDS usage including a UCF example.