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Get default via spacing and enclosures

TaherKotb

Hello,

I use dbCreateVia() function to create vias with variable cut Rows and Columns determined by the width of the path connected to the via in the layout view. In order to compute the cut Rows and Columns i need the via spacing and enclosure as inputs but these variables also change with the cut Rows and Columns values which i don't know.

Is there a skill function which allows to autmatically setup the array-side dependent via spacing rules and enclosures according to the input variable cut Rows and Cloumns? if not, is there any work around.

Thanks in advance 

Best Regards

Taher 

  • theopaone

     The values for the via spacing come from several constraints which you have to find from the techDB. The constraints I consider are minSpacing and minViaSpacing (for cutClass rules) for the "standard" spacing and viaSpacing for extra spacing for arrayed vias. I also get the width and length of the vias. Then I can calculate the number of vias in the rows and columns based on the "standard" spacing. If the rows and columns trigger the viaSpacing constraint, I change the spacing value and re-calculate.

    ROWS = fix( (areaWidth - viaWidth) / (viaWidth + viaHorizontalSpace) ) + 1

    COLUMNS = fix( (areaHieght - viaHeight ) / (viaHeight + viaVerticalSpace) ) + 1

     The viaSpacing is used if the number of adjacent cuts are greater than the constraint value. For a constraint value of 3, use the viaSpacing if ROWS > 1 and COLUMNS > 1. If the constraint value is 4, use the viaSpacing if the (ROWS > 1 && COLUMNS > 2) || (ROWS >  2 && COLUMNS > 1)

    Ted

  • dmay

    Will this command do what you need?

    lxComputeViaParams(
    d_viaDefID
    d_objID
    [ ds_constraintGroup ]
    [ l_params ]
    [ f_pathWidth1 ]
    [ t_pathDirection1 ]
    [ f_pathWidth2 ]
    [ t_pathDirection2 ]
    [ l_options ]
     )
         => list_of_params | nil

    Returns a list of DRC-correct via parameters for a specified standard via definition or a custom via definition that references either a cdsVia or a correctly-defined syEnhContact. The via parameters returned are: n_cutWidth, n_cutHeight, l_cutSpacing (X and Y), l_layer1Enc and l_layer2Enc (top, bottom, left, and right).

    Derek

  • TaherKotb

    Ted and Derek thanks alot for the reply.

     My problem was how to know via spacing and Enclosures if the inputs were the CutRows and CutColumns to avoid any DRC errors related to Via geometry. I needed the callback functions of the via instantation, which calulates the via spacing and enclosures based on the values of the Rows and Columns, but i could not find them so i figured out that if i used the leHiCreateVia() function then the callbacks function will be encoded automatically. In order to get the values of via parameters, i wrote this code

     ;**********Get Via Params******** 

     leHiCreateVia() ;;opens the create via interface

    viaForm = hiGetCurrentForm()

    viaForm->viaSingleModeScrollView->viaDefName->value=viaDefLayer

    viaForm->viaSingleModeScrollView->parameters->page1->computeEnc->enabled=t

    cutRowsIn = viaForm->viaSingleModeScrollView->parameters->page1->rows->value

    cutColumnsIn = viaForm->viaSingleModeScrollView->parameters->page1->columns->value=cutColumnsIn

    widthIn = viaForm->viaSingleModeScrollView->parameters->page1->width->value

    lengthIn = viaForm->viaSingleModeScrollView->parameters->page1->length->value

    rowSpacingIn = viaForm->viaSingleModeScrollView->parameters->page1->rowSpacing->value

    columnSpacingIn = viaForm->viaSingleModeScrollView->parameters->page1->columnSpacing->value

    layer1EncLeftIn = viaForm->viaSingleModeScrollView->parameters->page1->layer1EncLeft ->value

    layer2EncLeftIn = viaForm->viaSingleModeScrollView->parameters->page1->layer2EncLeft->value

    layer1EncRightIn = viaForm->viaSingleModeScrollView->parameters->page1->layer1EncRight->value

    layer2EncRightIn = viaForm->viaSingleModeScrollView->parameters->page1->layer2EncRight->value

    layer1EncTopIn = viaForm->viaSingleModeScrollView->parameters->page1->layer1EncTop->value

    layer2EncButtomIn = viaForm->viaSingleModeScrollView->parameters->page1->layer1EncButtom->value

    layer2EncTopIn = viaForm->viaSingleModeScrollView->parameters->page1->layer2EncTop->value

    layer2EncButtomIn = viaForm->viaSingleModeScrollView->parameters->page1->layer2EncButtom->value

    hiFormCancel(viaForm)

    viaTotalWidth = cutColumnsIn*widthIn + 2*max( layer1EncLeftIn layer2EncLeftIn ) + columnSpacingIn*(cutColumnsIn-1)

    viaTotalLength = cutRowsIn*lengthIn + 2*max( layer1EncTopIn layer2EncTopIn ) + rowSpacingIn*(cutRowsIn-1)  

    ;;**************END*******************

     ;************Draw Via using above params**************

    d_via = dbCreateVia( CellLayId viaDef XCoordwStep:YCoordwStep "R0" list( list("cutRows" cutRowsIn) list("cutColumns" cutColumnsIn) list("cutSpacing" list(rowSpacingIn columnSpacingIn)) list("layer1Enc" list(layer1EncLeftIn layer1EncTopIn)) list("layer2Enc" list(layer2EncLeftIn layer2EncTopIn)) list("cutWidth" widthIn) list("cutHeight" lengthIn) list("originOffset" list(0 0))))

    ;;***************END********************* 

    So every time i enter a new value for columns( like shown in the code cutColumnsIn ). i save the new params values in variables.

     Hope my findings would help

    Best Regards,

    Taher 

  • theopaone

     If you know the name of the form, you can look at the structure and find out the callbacks.

    Just sayin...

     Ted

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