ModelSim SE User's Manual - Electrical and Computer Engineering

UM-562 D - Verilog PLI / VPI / DPI
ModelSim SE User’s Manual
The storage for each usertf entry passed to the simulator must persist throughout the
simulation because the simulator de-references the usertf pointer to call the callback
functions. We recommend that you define your entries in an array, with the last entry set to
0. If the array is named veriusertfs (as is the case for linking to Verilog-XL), then you don't
have to provide an init_usertfs function, and the simulator will automatically register the
entries directly from the array (the last entry must be 0). For example,
s_tfcell veriusertfs[] = {
{usertask, 0, 0, 0, abc_calltf, 0, "$abc"},
{usertask, 0, 0, 0, xyz_calltf, 0, "$xyz"},
{0} /* last entry must be 0 */
};
Alternatively, you can add an init_usertfs function to explicitly register each entry from the
array:
void init_usertfs()
{
p_tfcell usertf = veriusertfs;
while (usertf->type)
mti_RegisterUserTF(usertf++);
}
It is an error if a PLI shared library does not contain a veriusertfs array or an init_usertfs
function.
Since PLI applications are dynamically loaded by the simulator, you must specify which
applications to load (each application must be a dynamically loadable library, see
"Compiling and linking C applications for PLI/VPI/DPI" (UM-568)). The PLI applications
are specified as follows (note that on a Windows platform the file extension would be .dll):
As a list in the Veriuser entry in the modelsim.ini file:
Veriuser = pliapp1.so pliapp2.so pliappn.so
As a list in the PLIOBJS environment variable:
% setenv PLIOBJS "pliapp1.so pliapp2.so pliappn.so"
As a -pli argument to the simulator (multiple arguments are allowed):
-pli pliapp1.so -pli pliapp2.so -pli pliappn.so
The various methods of specifying PLI applications can be used simultaneously. The
libraries are loaded in the order listed above. Environment variable references can be used
in the paths to the libraries in all cases.