User guide

D-15
Compiler Directives and System Tasks
System Tasks for LSI Certification VCD and EVCD Files
$lsi_dumpports
For LSI certification of your design, this system task specifies
recording a simulation history file that contains the transition times
and values of the ports in a module instance.
This simulation history file for LSI certification contains more
information than the VCD file specified by the $dumpvars system
task. The information in this file includes strength levels and
whether the test fixture module (test bench) or the Device Under
Test (the specified module instance or DUT) is driving a signal’s
value.
Syntax:
$lsi_dumpports(module_instance,"filename");
Code example:
$lsi_dumpports(top.middle1,"dumports.dmp");
If you would rather have the $lsi_dumpports system task
generate an extended VCD (EVCD) file instead, include the
+dumpports+ieee runtime option.
$dumpports
Creates an EVCD file as specified in IEEE Std. 1364-2001 pages
339-340.
You can, for example, input a EVCD file into TetraMAX for fault
simulation.
EVCD files are similar to the simulation history files generated by
the $lsi_dumpports system task for LSI certification, but there
are differences in the internal statements in the file. Further, the
EVCD format is a proposed IEEE standard format whereas the
format of the LSI certification file is specified by LSI.
In the past the $dumpports and $lsi_dumpports system