cphGetInstParamToCheck returning nil for instance but in CPH instance attribute parameters to check there are list of parameters in GUI

I just tried this, and it worked fine. I opened the physConfig in the editor, explicitly set the parameters to check for an instance, and then this worked.

However, if (say) the parameters to check are set on the cell level for the instantiated transistor, then it will return nil - you'd have to use cphGetCellParamToCheck. My guess is that this is what has happened in your case?

What you're seeing in the CPH editor for a given instance is the result of cphGetParamToCheck()

Regards,

Andrew

Thank you so much for the reply Andrew.

I created cph_lib library and schematic cph_cell that has all mos instances placed and did genfromsource. And used cphCreatePhysConfig to create config. mos  instances are taken from primitive library. So when i tried val=cphGetCellParamToCheck(physConfigID "primlib" "nmos") "nmos" is cellname of the device still returns nil. In UI I see two headers Instance and cell , in cell section i am able to see nmos and its parameters to check as well. Will try out some more experiments and let you know what works.

Thank you very much.

Sorry, I should have explained a bit more of the picture (I'd misread your original post and not noticed you'd just created the physConfig and not done anything to it). What happens is that what you see in the UI will be the result of any settings coming from a LAM file (typically in the PDK library directory, and then .cadence/dfII/cph/lam/cph.lam, but it could also look for a file called primlib.cph if that was the library name). In other words, where the devices are coming from. You can check the locations that are read by setting:

envSetVal("layoutXL" "lamReadFileMessage" 'boolean t)

and then opening the physConfig. 

If you use cphGetParamToCheck(physConfigID "mp47") (the hierarchical path to the instance is what you give as the second argument) it should show the resolved value coming from the LAM, cell, instance and occurrence settings in the physConfig.

Regards,

Andrew

Thank you so much Andrew. This worked. there is lam file forgot to mention that gets the param to check data for the library. Wanted to get that data in Skill for further processing. Thank you very much for the help.

lamfile is located in <PATH_TO_LIBRARY>/.cadence/dfII/cph/lam/cph.lam 

used: envSetVal("layoutXL" "lamReadFileMessage" 'boolean t) ( this function indicates LAM file has been read by the current Layout XL session.

physConfigID=cphOpenConfig("cph_lib" "cph_cell" "physConfig" "r")

 cphGetParamToCheck(physConfigID "mp47")
And was able to get the parameter list