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Force db update/refresh regarding connectivity and pcell parameters

frankliu

Problem statement:

1. In layout XL create a (metal) rectangle and add a net name to it.

2. In skill add a (same layer) rectangle that abuts or overlaps this rectangle

3. Query the associated nets with this new rectangle in skill

   Result: its net name does not get updated

   Expected result : the net name associated with 1.



Note:

If instead of 2. you manually create a rectangle from the layout editor, then the query in 3., works as intended.

If I put a breakpoint between 2 and 3 then 3. works

If I add a dbSave between 2 and 3 then 3. works



I would like to avoid using dbSave, since this is too heavy handed and slows down my script.  I would like the connectivity information to be updated at the end of 2.  Please let me know if there is a way of updating this information.



Note:

In the title I also mention pcell parameters, this also happens with pcells, I know that in some cases you have to call the callback function associated with a parameter in the pcell, and I have, but a similar situation happens.  For example in a transistor pcell, when I change the number of fingers, and then query for the geometry of the poly, I don't get an updated number, and as in the connectivity example above, if I insert a breakpoint or perform a dbSave then the information gets updated.  Clearly something must be called within dbSave or when restarting from a breakpoint to update the connectivity / cell parameters.



Sorry if this is not clear, please let me know if you need further details.

Parents
  • Thanks Lawrence, I agree with you that I can check for overlaps, and change the connectivity, yes this could be a work around, but I don't have a work around for pcell parameters.

    That is, if I change a parameter like number of fingers, and I call the related callback function, from skill, and then query for the geometry of the fingers, I don't get the updated list of rectangles. Note I used Andrew's code: CCSinvokeCdfCallbacks(geGetEditCellView())

    And as mentioned previously, if I do a dbSave or put a breakpoint after changing the number of fingers, things work correctly.

    I need geometry information of the underlying pcell after a change of parameters and I don't know how this can be obtained otherwise.

    But in either case, it seems that some kind of refreshing the db function should be provided.
Reply
  • Thanks Lawrence, I agree with you that I can check for overlaps, and change the connectivity, yes this could be a work around, but I don't have a work around for pcell parameters.

    That is, if I change a parameter like number of fingers, and I call the related callback function, from skill, and then query for the geometry of the fingers, I don't get the updated list of rectangles. Note I used Andrew's code: CCSinvokeCdfCallbacks(geGetEditCellView())

    And as mentioned previously, if I do a dbSave or put a breakpoint after changing the number of fingers, things work correctly.

    I need geometry information of the underlying pcell after a change of parameters and I don't know how this can be obtained otherwise.

    But in either case, it seems that some kind of refreshing the db function should be provided.
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