User guide

C-16
Simulation Options
Note:
VCS automatically increases the buffer size as needed to comply
with this limit.
+vpdfile+filename
Specifies the name of the output VPD file (default is
vcdplus.vpd). You must include the full file name with the .vpd
extension.
+vpdfilesize +number_of_megabytes
Creates a VPD file that has a moving window in time while never
exceeding the file size specified by number_of_megabytes.
When the VPD file size limit is reached, VPD continues saving
simulation history by overwriting older history.
File size is a direct result of circuit size, circuit activity, and the
data being saved. Test cases show that VPD file sizes will likely
run from a few megabytes to a few hundred megabytes. Many
users can share the same VPD history file, which may be a reason
for saving all time value changes when you do simulation. You
can save one history file for a design and overwrite it on each
subsequent run.
+vpdfileswitchsize+number_in_MB
Specifies a size for the vpd file. When the vpd file reaches this
size, VCS closes this file and opens a new one with the same
hierarchy as the previous vpd file. There is a number suffix added
to all new vpd file names to differentiate them. For example: simv
+vpdfile+test.vpd +vpdfileswitchsize+10 The first vpd file is
named test.vpd. When its size raches 10 MB, VCS starts a new
file test_01.vpd, the third vpd file is test_02.vpd, and so on.