Input Files

Xilinx tools can read *.edn and *.sxnf netlist formats. Since Synopsys creates the *.sxnf file you will need to use that as input to the Xilinx tools. In addition, if you created a constraint file with Synopsys, you should use it in the place-and-route stage as well. This is the *.ncf or netlist constraint file, that contains clock, net, area, and pad constraints. In addition to the netlist constraint file you can specify your own constraints in the user constraint file (*.ucf) and also use it as input to the Xilinx tools. The *.ucf file takes priority over the *.ncf file so you can use it to overwrite the constraints that you have set during synthesis.