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docs/Simulation/Commercial-Simulators.rst

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+Commericial Simulators
+==============================
+The ReBAR framework currently supports only the VCS commerical simulator
+
+VCS
+-----------------------
+VCS is a commercial RTL simulator developed by Synopsys. It requires commerical licenses.
+The ReBAR framework can compile and execute simulations using VCS. VCS simulation will generally compile
+faster than Verilator simulations.
+
+To run a simulation using VCS, perform the following steps:
+
+Make sure that the VCS simulator is on your `PATH`.
+
+To compile the example design, run make in the ``sims/vsim`` directory.
+This will elaborate the DefaultExampleConfig in the example project.
+
+An executable called simulator-example-DefaultExampleConfig will be produced.
+This executable is a simulator that has been compiled based on the design that was built.
+You can then use this executable to run any compatible RV64 code. For instance,
+to run one of the riscv-tools assembly tests.
+
+::
+    ./simulator-example-DefaultExampleConfig $RISCV/riscv64-unknown-elf/share/riscv-tests/isa/rv64ui-p-simple
+
+If you later create your own project, you can use environment variables to
+build an alternate configuration.
+
+::
+    make PROJECT=yourproject CONFIG=YourConfig
+    ./simulator-yourproject-YourConfig ...
+
+If you would like to extract waveforms from the simulation, run the command ``make debug`` instead of just ``make``. This will generate a vpd file (this is a proprietry waveform representation format used by Synopsys) that can be loaded to vpd-supported waveform viewers. If you have Synopsys licenses, we recommend using the DVE waveform viewers