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  2. Custom IC SKILL
  3. update "cutSpacing" of a via

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update "cutSpacing" of a via

chianga
chianga over 12 years ago

Hi guys,

Long time lurker, first time poster.  I first want to thank Andrew, Lawrence and other regulars for contributing to this forum.

 I have a simple problem that I can't seem to figure out and I am hoping you guys can point me to the right direction.  I am trying to update the "cutSpacing" of a via using the following code, where cutSpacing= x_width:y_width and I got the error below

*Error* dbReplacePropList: Invalid float - (0.09 0.09)

I figured I am not setting the type of "cutSpacing" correctly but I can't figure what it should be. 

  dbReplacePropList(fig

               list(

   list("cutSpacing" 'float cutSpacing)

                   list("cutColumns" 'int numCols)

                   list("cutRows" 'int numRows)

   )

) 

Thanks in advance,

Andy

PS I am using IC6.1.5-64b.500.12 

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  • Andrew Beckett
    Andrew Beckett over 12 years ago

    Andy,

    The 'float before cutSpacing should be 'list. That's because cutSpacing is a list of two floats, rather than a single float.

    Regards,

    Andrew.

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  • chianga
    chianga over 12 years ago

    Hi Andrew,

     

    thank you for the quick reply, the problem is fixed with 'list.

     

    Andy 

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  • chianga
    chianga over 12 years ago

    I have one more question, relating to via cutSpacing, please let me know if I should start a new thread.

    The goal of my code is to create a bindkey such that I can grow and shrink via on the fly and adjust viaSpacing accordingly. 

     Basically since 2x2 and 3x3 vias in the newer technology node have different via spacing requirements, I am using the code below to extract these infomation for the 3x3 vias.  Two by two cutSpacing can be easily obtained using via->viaHeader->viaDef->params.

     The problem I am running into is that lxGetValidViaDefs is extremely slow and this is especially true when multiple vias are selected.  So I am wondering if there is any other way to retrieve the "spacings" information inside the tech files without using  lxGetValidViaDefs and lxComputeViaParams?

     I guess one way to bypass all these is to only retrieve via spacing info when via is either 2x2 or 3x3(right now my code does this calculation everytime the bindkey is hit)  but I am curious to know if there is a more clean way of doing this.

     

    ;get via spcaing parameters for 3x3 via

    layer1=fig->viaHeader->viaDef->layer1->name

    layer2=fig->viaHeader->viaDef->layer2->name

    cellViewId=geGetEditCellView()

    viaId=caar(lxGetValidViaDefs(cellViewId nil layer1 layer2))

    viaParams=list(list("cutRows" 3) list("cutColumns" 3))

    viaParams=lxComputeViaParams(viaId cellViewId nil viaParams)

    threeX=caadr(assoc("cutSpacing" viaParams))

    threeY=cadadr(assoc("cutSpacing" viaParams)) 

     Thanks again,

    Andy 

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  • Andrew Beckett
    Andrew Beckett over 12 years ago

    Andy,

    If your via spacing is dependent upon the number of vias, that can be encoded as a technology rule in the constraints in the tech file. Isn't that a better solution than having to compute it yourself every time you change the number of rows and columns? That way it will be correct no matter how you enter the rows and columns of the via...

    Look for viaSpacing in cdnshelp and you should find it descrbed in the Virtuoso Technology Data ASCII Files Reference manual.

    Andrew.

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  • chianga
    chianga over 12 years ago

    HI Andrew,

     thanks for the reply.  I was having problem finding the correct function to retrieve that data from the tech file but with a bit more digging in the forum, I came up with the solution below just in case someone else is interested doing similar things in the future.

     

    ;get via spcaing parameters for 3x3 via

    tfId=techGetTechFile(geGetEditCellView())

    viaName=car(fig->viaHeader->viaDef->params)

    viaParams=techGetSpacingRule(tfId "viaSpacing" viaName)

    threeX_spacing=caddr(viaParams)

    Thanks again for the help and happy holidays,

    Andy 

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  • Yanhong
    Yanhong over 11 years ago

     Hi there,

    I am very new to this community. I am trying to implement creating via automatically using skill code. Thanks for all the information that you provided. I was able to place the via wher I want using skill code. However, in terms of the VIA params, I would like to create a via with the same parameters as what "auto" option provided on the "Via form". The auto via will cover all overlap area and extend over a little bit. Also, it won't violate the DRC rule, etc. I tried to use lxComputeViaParams for the viaDef that from tech file, but it didn't give much info. Is there any SKILL function to do that? 

    Thanks,

    Yanhong

                tf=techGetTechFile(cv)
                viaDef=techFindViaDefByName(tf viaDefName)
                via_center_point_x=(car(viabox_ll)+car(viabox_ur))/2
                via_center_point_y=(cadr(viabox_ll)+cadr(viabox_ur))/2
                via_center_point=list(via_center_point_x via_center_point_y)

                viaParams=list(list("cutRows" evalstring(cutRows)) list("cutColumns"     evalstring(cutColumns)) )

                ;viaParams=append(viaParams lxComputeViaParams(viaId cv viaParams))
                existing_via=setof(z dbGetTrueOverlaps(cv list(viabox_ll viabox_ur)) rexMatchp("Via" z~>objType)==t)
                if(existing_via
                  then
                  printf("There is an existing VIA. No Via will be created.\n")
                else
                  if(viaDef
                    via0=dbCreateVia(cv viaDef via_center_point "R90" viaParams)

     

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