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 ncsim without any optimization 

Last post Wed, Nov 30 2011 2:57 AM by beatsonline. 2 replies.
Started by beatsonline 25 Nov 2011 07:22 AM. Topic has 2 replies and 2270 views
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  • Fri, Nov 25 2011 7:22 AM

    ncsim without any optimization Reply
    Hi, I want to run my behavioral model using ncsim without any optimization. I look at different option like -linedebug , -access +rwc but none will stop all the optimization like modelsim does with -novopt. Is there any equivalent option is NCSIM? I want to do this because my simulation is giving different results in optimized and non-optimized case using modelsim. What could be main reason? Thanks!!
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    • Post Points: 20
  • Sun, Nov 27 2011 10:31 AM

    • TAM1
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    Re: ncsim without any optimization Reply

    99% of the issues like this are due to race-conditions in the Verilog model. If you have access to an account on support.cadence.com, do a search for "Race Conditions". There is an Application Note that explains what might be going on in your simulation. If you have an issue where the order in which events occur in a timestep affects the simulation results, removing more optimizations may not solve it since Verilog doesn't enforce any particular event order for its signal transitions.

    • Post Points: 20
  • Wed, Nov 30 2011 2:57 AM

    Re: ncsim without any optimization Reply
    Thanks TAM, it was indeed a case where order of event was affecting the simulation result. Although finding out these problem location is not straight forward job. Comparing optimized and non-optimized case can help to reach the suspect point.
    • Post Points: 5
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Started by beatsonline at 25 Nov 2011 07:22 AM. Topic has 2 replies.