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Simulators >> Circuit Simulators >> Spectre Simulation Result Not Update
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Message started by stephen on May 12^th, 2005, 12:45pm

Title: Spectre Simulation Result Not Update
Post by stephen on May 12^th, 2005, 12:45pm

Version: IC5.0.33, running on linux 7.2

My problem is that sometimes after I change my schematic or simulation parameters, the simulation result refuses to update. I check the netlist and the netlist is correctly updated. I also check the simulation result file "tran.tran". The file date is updated. However, the content has no change at all. The file size won't change even if I make the simulation time much longer. There are no error messages at all during the simulation. All I see is "simulation successful". It seems spectre has a cache version of the netlist and refuses to load the new netlist. The only way for me to get around this problem when it happens is to quit the "Cadence Analog Design Environment" window and re-open it, or, directly kill the spectre process.

This is very annoying because it can happen to me more than 10 times in a single day. This has never happened when I was using IC5.0.00.

I found the spectre process remains in memory even after a simulation has finished. It only disappears when I quit the entire design "Cadence Analog Design Environment". Is it a new feature in IC5033 for spectre to stay resident in memory?

Please advise. Thanks.

Title: Re: Spectre Simulation Result Not Update
Post by Andrew Beckett on May 17^th, 2005, 10:21am

This is not a new feature - but it should not behave the way you describe. What should happen is that spectre doesn't restart unless the design changed - to make it quicker. If a parameter changes, that can be passed directly from ADE to spectre, and this saves the startup time, netlist reading, and license checkout.

However, something is clearly going wrong here. I suggest you contact customer support via your normal channel. As a short term measure, you can do:

envSetVal("spectre.envOpts" "controlMode" 'string "batch")

in the CIW before starting ADE, and this will force spectre to restart every time. The downside is that this slows things down a bit with parametric sweeps and so on.

Regards,

Andrew.