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Simulators >> Circuit Simulators >> oceanEval syntax and monte carlo measurements
https://designers-guide.org/forum/YaBB.pl?num=1117551568

Message started by Richard Tseng on May 31^st, 2005, 7:59am

Title: oceanEval syntax and monte carlo measurements
Post by Richard Tseng on May 31^st, 2005, 7:59am

Hello all,
I'm trying to learn spectre because it can track correlations by device instances.

I'm writing out my netlists manually, and I'm trying to the measure propagation delay across a gate. The spectre user guide and reference (and the do measurements with the oceanEval statement:

export somesignal=oceanEval("some expression")

I couldn't find any documentation on how oceanEval was supposed to be used, and the some expression in the brackets looked like it was from spectreMDL, so my code ended up looking like:

mc1 montecarlo numruns=10 seed=1 variations=process savefamilyplots=yes {
vtran tran start=0 stop=10n step=50p
export tdelay=oceanEval("deltax(sig1=in,sig2=out,dir1='rise, n1=3, thresh1=0.6, start1=0, dir2='fall, n2=3, thresh2=0.6 start2=0)")
}

How can I measure propagation delays (and other such derived values) in a monte carlo simulation without going through the gui? All I need are the values; I’ll run the rest through Matlab.

Also, what is the right way to use oceanEval?

Thanks a lot!
Richard Tseng

Title: Re: oceanEval syntax and monte carlo measurements
Post by Andrew Beckett on May 31^st, 2005, 10:49am

Hi Richard,

It's not a spectreMDL expression (unfortunately), it's an OCEAN expression. Read the OCEAN documentation for more details.

The reason it's OCEAN is largely historical - OCEAN predates spectreMDL. Hopefully one day it will move to using MDL, or at least give a choice.

Regards,

Andrew.