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Simulators >> Circuit Simulators >> OceanEval syntax in spectre
https://designers-guide.org/forum/YaBB.pl?num=1144270127

Message started by jerry on Apr 5^th, 2006, 1:48pm

Title: OceanEval syntax in spectre
Post by jerry on Apr 5^th, 2006, 1:48pm

Hello all,

I am trying to finish my course project by spectre. I am trying to run Monte Carlo simulation through my netlist, and measure the propagation delay across a gate. I search through all the accessible spectre documents about Monte Carlo simulation, they all do measurement through 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:

m1 montecarlo saveprocessparams=yes processscalarfile="../process.dat"
+ numruns=30 variations=process seed=10{
dcop1 dc
tran1 tran start=0 stop=0.2ns step=0.01ns
export nor1in1=oceanEval("deltax(sig1=nor1in1, sig2=nor1out, dir1='rise, n1=1, start1=0, thresh1=0.75, dir2='fall, n2=1, start2=0, thresh2=0.75)")
}

However, when I type "spectre myinputfile" in the terminal, some errors display in the terminal like:

Error found by spectre during circuit read-in.
"gatesizing.spi" 105: Function `oceaneval' is undefined or is used
recursively.
"gatesizing.spi" 105: VCVS (export) needs 4 nodes (0 given).

How can I measure the propagation delay in a Monte Carlo simulation without going through the gui? All I need are the values; I'll run the rest through Matlab.

Thanks!
Jerry

Title: Re: OceanEval syntax in spectre
Post by Andrew Beckett on Apr 11^th, 2006, 10:06pm

The expression within the oceanEval argument has to be an OCEAN expression - as you'd get through the ADE calculator. It's not MDL.

One day we'll allow MDL to be used there - but for now you need to use an OCEAN expression. See the OCEAN documentation for more details.

If you generate the netlist via ADE, it's pretty easy to set this up.

Regards,

Andrew.