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Altera_Forum's avatar
Altera_Forum
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13 years ago

ModelSim/QuestaSim Batch mode with waveform stimulus

Hi ,

I have been trying to simulate a very large setup on ALTERA Modelsim 6.6 and the simulation time of 5ms in real time is taking almost 18 hours. And performing debug at this rate is really impacting my deliverables.

Does ModelSim have a batch mode operation and if yes can I save like a snap shot of my simulation till a certain time say 1 or 2 ms till which there is no bug and later on force this as a stimulus in my Testbench so that the Simulation starts from a point at which it is triggered i.e., after 2 ms (say).

This way I can potentially save good amount of run time and debug can be performed efficienly I feel.

Kindly respond.

Incase ModelSim ain't having this capability Pls let me knwo if QuestaSim 10.1 can do the task.

Kindly let me know the way of doing this Batchmode with Waveform Stimulus.

Thank you in advance.

Dee :):)

1 Reply

  • Altera_Forum's avatar
    Altera_Forum
    Icon for Honored Contributor rankHonored Contributor
    13 years ago

    Your design can run considerably faster on Questa as there are no RTL or gate-level optimizations in ModelSim.

    You will also save time in either version of ModelSim or Questa, interactive or batch, by waiting to turn on signal logging until after 2ms have passed.

    The way to get batch mode from waveform stimulus is to export the wave data into a Verilog or VHDL testbench so you can load it in as your top-level design unit. Then you can run your simulation in batch and use the checkpoint/restore commands to save simulation cycles. This is all described in the ModelSim/Questa user guide.