Technical data

Specifying SDF files for simulation
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Standard Delay Format (SDF) Timing Annotation ModelSim EE/PLUS Reference Manual
Specifying SDF files for simulation
Model
Sim
supports SDF versions 1.0 through 2.1. The simulator’s built-in SDF
annotator automatically adjusts to the version of the file. Use the following
vsim
(p91) command-line options to specify the SDF files, the desired timing values,
and their associated design instances:
-sdfmin [<instance>=]<filename>
-sdftyp [<instance>=]<filename>
-sdfmax [<instance>=]<filename>
Any number of SDF files can be applied to any instance in the design by
specifying one of the above options for each file. Use
-sdfmin
to select minimum,
-sdftyp
to select typical, and
-sdfmax
to select maximum timing values from the
SDF file.
Instance specification
The instance paths in the SDF file are relative to the instance that the SDF is
applied to. Usually, this instance is an ASIC or FPGA model instantiated under a
testbench. For example, to annotate maximum timing values from the SDF file
myasic.sdf
to an instance
u1
under a top-level named
testbench
, invoke the
simulator as follows:
vsim -sdfmax /testbench/u1=myasic.sdf testbench
If the instance name is omitted then the SDF file is applied to the top-level.
This
is usually incorrect
because in most cases the model is instantiated under a
testbench or within a larger system level simulation. In fact, the design may have
several models, each having its own SDF file. In this case, specify an SDF file for
each instance. For example,
vsim -sdfmax /system/u1=asic1.sdf -sdfmax /system/u2=asic2.sdf system