Compiling Verilog Libraries

Synthesis and Simulation Design GuideChapter 5: Simulating Your Design

Compiling Verilog Libraries

For some Verilog simulators, such as NC-Verilog and ModelSim, you may need to compile the Verilog libraries before you can use them for design simulations. A pre-compiled library methodology has the advantage of speeding up the simulation of your designs. You do not need to compile the libraries for Verilog-XL because it uses an interpretive compilation of the libraries. To simulate Xilinx designs, you need the following simulation libraries.

UniSim Library - The UniSim library is used for behavioral (RTL) simulation with instantiated components in the netlist, and for post-synthesis (pre-M1) simulation. The Verilog library has separate libraries for each device family: uni3000, UniSims (XC4000E/L/X, Spartan/XL, and Virtex), uni5200, uni9000.
LogiBLOX Library - The LogiBLOX library is used for designs containing LogiBLOX components, during pre-synthesis (RTL), and post-synthesis simulation. Verilog uses SimPrim libraries.
SimPrim Library - The SimPrim library is used for post Ngdbuild (gate level functional), post-Map (partial timing), and post-place-and-route (full timing) simulations. This library is architecture independent.

Compiling Libraries for ModelSim

For detailed instructions on compiling these simulation libraries, see the instructions in Xilinx Solution # 1923 which is available at http://www.xilinx.com/techdocs/1923.htm.

After compiling the libraries, notice that ModelSim creates a file called modelsim.ini. View this file and notice that the upper portion defines the locations of the compiled libraries. When doing a simulation, you must provide the modelsim.ini file either by copying the file directly to the directory where the HDL files are to be compiled and the simulation is to be run, or by setting the MODELSIM environment variable to the location of your master .ini file. You must set this variable since the ModelSim installation does not initially declare the path for you. For UNIX, type the following.

setenv MODELSIM /path/to/the/modelsim.ini