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Problem building a slotted metal pcell

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Hi, I am trying to make a pcell that will create a big piece of metal with slots chopped out of it (for mechanical stress relief). I started with a prototype SKILL code that will create the slotted metal as an instance, and it worked ("prototype.il"). When put into pcell form, the pcell code compiles successfully. But the pcell instance can only have 14 slots max and fails otherwise. Warnings are always generated whether there is pcellEvalFailed or not. (I've appended the warnings generated to the end of "slot_pcell.il"). It seems that the database ID of the metal object becomes nil after being accessed repeatedly, so leChopShape stops working. (1) Could anyone help to point out what's wrong with the code/method? (2) I used leChopShape in the pcell, which is not a recommended function for pcells. Is there another way to make slots in layers? (3) In SKILL, is there a way to exit a loop prematurely, or skip some of the iterations (next/last functions) ? Thanks in advance :) KK


Originally posted in cdnusers.org by kkchen
prototype.il
Parents
  • archive

    1. The code I downloaded was missing a paren at the end to close the pcDefinePcell. Also the leChopeShape was periodically creating a new object. If I changed the call to make_slot like this:

    shape_id = make_slot(shape_id sw nw ne se sw)

    Then it worked. HOWEVER, performance was terrible since leChopShape is so slow.

    2. If you are in Cadence 5.1.41 USR2 or later (I think that is the requirement), you can use some dbLayer commands. When I changed the code to simply create a metal1 shape and then create small polygons and run a dbLayerAndNot, I was able to remove the leChopShape and performance was great.


    ; chop out slot
    when(chop_abort != 1
    shp = dbCreatePolygon(pcCellView "y0" list(sw nw ne se sw))
    shps=cons(shp shps)
    )

    ) ; end this_row for let
    ) ; end this_row for
    ) ; end this_col for let
    ) ; end this_col for
    dbLayerAndNot(pcCellView "metal1" list(shape_id) shps)
    mapcar('dbDeleteObject shps)
    dbDeleteObject(shape_id)

    3. If you want to exit a loop, use a while loop with a counter

    loop = t
    row = 0
    while(loop
    do skill here
    row++
    when(a
    loop=nil
    )
    )


    Originally posted in cdnusers.org by dmay
Reply
  • archive

    1. The code I downloaded was missing a paren at the end to close the pcDefinePcell. Also the leChopeShape was periodically creating a new object. If I changed the call to make_slot like this:

    shape_id = make_slot(shape_id sw nw ne se sw)

    Then it worked. HOWEVER, performance was terrible since leChopShape is so slow.

    2. If you are in Cadence 5.1.41 USR2 or later (I think that is the requirement), you can use some dbLayer commands. When I changed the code to simply create a metal1 shape and then create small polygons and run a dbLayerAndNot, I was able to remove the leChopShape and performance was great.


    ; chop out slot
    when(chop_abort != 1
    shp = dbCreatePolygon(pcCellView "y0" list(sw nw ne se sw))
    shps=cons(shp shps)
    )

    ) ; end this_row for let
    ) ; end this_row for
    ) ; end this_col for let
    ) ; end this_col for
    dbLayerAndNot(pcCellView "metal1" list(shape_id) shps)
    mapcar('dbDeleteObject shps)
    dbDeleteObject(shape_id)

    3. If you want to exit a loop, use a while loop with a counter

    loop = t
    row = 0
    while(loop
    do skill here
    row++
    when(a
    loop=nil
    )
    )


    Originally posted in cdnusers.org by dmay
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