Technical data

ModelSim VITAL compliance
ModelSim EE/PLUS Reference Manual ModelSim and VITAL
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433
VITAL compliance checking
Compliance checking is important in enabling VITAL acceleration; to qualify for
global acceleration, an architecture must be VITAL-level-one compliant. VCOM
automatically checks for VITAL 3.0 compliance on all entities with the
VITAL_Level0 attribute set, and all architectures with the VITAL_Level0 or
VITAL_Level1 attribute set.
If you are using VITAL 2.2b, you must turn off the compliance checking either by
not setting the attributes, or by invoking
vcom
(p71) with the option
-
novitalcheck
. It is, of course, possible to turn off compliance checking for VITAL
3.0 as well; we strongly suggest that you leave checking on to ensure optimal
simulation.
VITAL compliance warnings
The following LRM errors are printed as warnings (if they were considered errors
they would prevent VITAL level 1 acceleration) ; they do not affect how the
architecture behaves.
• Starting index constraint to DataIn and PreviousDataIn parameters to
VITALStateTable do not match (1076.4 section 6.4.3.2.2)
• Size of PreviousDataIn parameter is larger then the size of the DataIn parameter
to VITALStateTable (1076.4 section 6.4.3.2.2)
• Signal q_w is read by the VITAL process but is NOT in the sensitivity list
(1076.4 section 6.4.3)
The first two warnings are minor cases where the body of the VITAL 3.0 LRM is
slightly stricter then the package portion of the LRM. Since either interpretation
will provide the same simulation results, we chose to make these two cases just
warnings.
The last warning is a relaxation of the restriction on reading an internal signal that
is not in the sensitivity list. This is relaxed only for the CheckEnabled parameters
of the timing checks, and only if it is not read elsewhere.
You cannot control the visibility of VITAL compliance-check warnings in your
vcom
(p71) transcript. They can be suppressed by using the
vcom -nowarn
switch
as in
vcom -nowarn 6
. The 6 comes from the warning level printed as part of the
warning, i.e., WARNING[6]. You can also add the following line to your
modelsim.ini
file in the [vcom] section (p416).
[vcom]
Show_VitalChecksWarnings = 0