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  3. Can I set preferences for the default operating point cdsParam...

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Can I set preferences for the default operating point cdsParam definitions in my .cdsinit?

CADcasualty
CADcasualty over 6 years ago

When I turn on annotations to view transistor operating point information via the cdsParam(n) labels, I get a default set of assignments that don't work well for me (although they likely work for other people just fine). Is there a way that I can define my preferences for MOS operating point cdsParams that isn't tied to any given cell/schematic i.e. I want my settings to be *global* preferences - ideally defined in my .cdinit e.g.

cdsParam(1)=id, cdsParam(2)=vgt, cdsParam(3)=vdsat, cdsParam(4)=gm, cdsParam(5)=rout   etc.

Thanks.

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  • Andrew Beckett
    Andrew Beckett over 6 years ago

    You can either set the effective CDF in the .cdsinit for each device to change the label display information (the CDF is used to seed the annotation setup), or use the annLoadAnnotationData to load your annotation setup for each window (you can't do this in the .cdsinit because it needs a window id). So you could define a bind key to load it or use a trigger (e.g. deRegUserTriggers) to load the annotation setup when a schematic window is opened, say.

    Regards,

    Andrew.

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  • CADcasualty
    CADcasualty over 6 years ago

    In coming up with the following, I was referencing the "Creating Labels with SKILL" section in the "Component Description Format User Guide" manual.

    Is the right way to go about this to include a full spread of lines like the following in my .cdsinit:

    cdfCreateUserCellCDF(ddGetObj("tsmc18" "nmosmvt5v"))->opPointLabelSet = "id vgt vdsat gm rout"

    (I used cdfCreateUserCellCDF instead of cdfCreateBaseCellCDF which was depicted in the manual)

    Couple other things:

    1. It's neat that when using the annotations setup form you can set the cell to the wildcard specification *mos* and get all the MOS transistors over with in one go. Wish that was possible in the skill/.cdsinit domain.

    2. I noticed the following curiosity when following the examples in the manual:

    libId = ddGetObj("tsmc18")
    dd:0x21014a40
    >
    cell = ddGetObj(libId "nmosmvt5v")
    *Error* ilGetString: arg must be symbol or string - dd:0x21014a40

    The documentation implied the command that gave an error result should have worked. I then tried the following command that did work:

    cell = ddGetObj("tsmc18" "nmosmvt5v")
    dd:0x20fed4f8

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  • CADcasualty
    CADcasualty over 6 years ago in reply to CADcasualty

    Hi Andrew - would you mind please confirming the first part of my previous post. What I did doesn't seem to be working...

    I have confirmed that the effective CDF's are all properly set in accordance with the cdfCreateUserCellCDF commands in my .cdsinit but I don't see it reflected in the annotations. I then looked at the annotations setup window and it's still using the default list for opPointLabelSet. I've restarted Virtuoso and the issue persists :-(.

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  • CADcasualty
    CADcasualty over 6 years ago in reply to CADcasualty

    I've been pouring more time into this and I've discovered that the effective CDF only takes effect when you bring up the Annotation Setup form and in the Setup menu you select Retrieve from Effective CDF. Once I do that all is good. I then tried to incorporate doing that into my .cdsinit and discovered the annRetrieveFromEffectiveCDF function, however it needs a window ID argument so now I'm not sure this is doable in my .cdsinit anymore :-(. 

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  • Andrew Beckett
    Andrew Beckett over 6 years ago in reply to CADcasualty

    Apologies for the delay - I've been busy this week (out of the office). The Effective CDF should be OK if set before the annotations are used - they seed the initial annotation settings. The only time you need to use the Retrieve from Effective CDF is when you change it within the session and need to refresh the annotation system to use the latest Effective CDF setup.

    So setting the Effective CDF in the .cdsinit should be fine, as far as I know... at least, I just checked it and it worked for me.

    Regards,

    Andrew.

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  • CADcasualty
    CADcasualty over 6 years ago in reply to Andrew Beckett

    Even though I've done this before, I just tried quitting and restarting virtuoso - my .cdsinit was executed (which set up all of my user cdfs) and now it seems everything is working - just like when you confirmed it for yourself. I'm not sure what it was giving me issue before but for now it appears I'm good. Thanks for your help.

    For bonus points, I'd appreciate you looking at points 1 & 2 in my post from 11 days ago, but don't worry about it if you're too busy - you've successfully gotten me up and running and that's the main thing. Thanks again!

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  • Andrew Beckett
    Andrew Beckett over 6 years ago in reply to CADcasualty

    For question 1, you'd have to write some SKILL to match the components in your library (using pcre functions across all cells, say) and then updating the CDF in a loop. There's no convenient wildcard function to update the CDF.

    For question 2, that's a mistake in the Component Description Format User Guide (on a couple of pages) and in the Analog Design Environment L SKILL Reference manual (on one page). I searched across all the documentation and didn't find the similar mistake elsewhere. The library must be specified as a string, and not as a ddObj when ddGetObj is called. So you could do:

    libId = ddGetObj("tsmc18")
    dd:0x21014a40
    >
    cell = ddGetObj(libId->name "nmosmvt5v")

    Andrew.

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