General Description: When I use the "-ism" switch, NGD2VER does not insert all the required SIMPRIM models:
- X_INV is missing from post-NGDBuild netlist - X_ONE and X_ZERO are missing from post-PAR netlist
This is fixed in the 6.1i software.
Prior to 6.1i, to work around this issue, you must compile the X_INV or X_ONE and X_ZERO simulation models along with the simulation netlist when running a simulation.
If you are using the "-ism" to archive a design, the X_INV, X_ONE, and X_ZERO models must be archived with the design as well.
The Verilog simulation models are located in the Xilinx software at $XILINX/verilog/src/simprims. Copy X_INV.v, X_ONE.v, and X_ZERO.v from this directory and place them into the same directory as the simulation netlist.