Hello All ,
I have a script which I use to calculate a particular net's Net Length, total net resistance, Capacitance (w.r.t ground).
But the drawback is that I have to select the entire Net before invoking the "NetLength" Function.
So I want a script which can trace the entire net and give a list of metals, vias, instances that
belong to this net. i.e I will select any one metal/instance/via
of a net and the code should trace the entire net and give me the
NOTE: Instances here refer to instances/mosaics of vias.
Well, if the layout was created using Virtuoso XL, then this is easy - since all shapes on the net will be associated with the net in the database.Other than that, you could use Diva to extract a net - or you'd have to write something which traced the net - not that straightforward.Regards,Andrew.
Thanks Andrew.Thats what I was asking for. A skill code which can trace the net in Virtuoso Layout Editor.Regards,Sathya
I wrote some skill code to do this and presented it at the 2002 Cadence Users Group. It was no small program, but basically used dbGetTrueOverlaps on shapes decomposed into rectangles. If your nets are not traversing the hierarchy, then using VXL connectivity information is the easiest way to go. DIVA also provides a quick extraction, but custom Skill was the only way we found that we could extract the shapes from any level of hierarchy by clicking on a shape.I can't give you the code, but I have attached my paper and presentation from the 2002 conference. The effort to write the code has paid off many times over. We can click on a net and hilight it, but we then have all the shapes and can do whatever we want with them.-Derek
I reread the first post and you mention that you "select" every shape on the net first. If this is the case, then VXL is your best bet. VXL adds connectivity to the shapes on the same net. You can then select all shapes on a net with something as simple as this:shapes = setof(x geGetEditCellView()~>shapes x~>net~>name == "mynet")You can get every instance (including vias) connected to the net using:insts = setof(x cv~>conns x~>net~>name=="mynet")The paper I attached describes how to get all shapes in the hierarchy of the design on a net, all the way down to the gate without needing VXL.-Derek
Im using only VLE not VXL so I think I will just read ur paper and try to write my code myself.
Meanwhile if there are nayone out there who can give the code are welcome.