netlist extraction from gdsii file only.

hello boys and girls:
the following issue I met block my route and dont know how to solve it.
The issue is :
I have a gdsII file only, I can view all the devices in virtuoso layout.
so I want to get a netlist from gdsII with assura. but dont know how
to do that. in fact I have assura drc lvs and pre rule files.
I wanna get a verilog netlist from the damning gdsii file also.
it is a very great help I will get from you. thank you first.

 

You can use the assura UI to run a LVS job. However, it will
refuse to run if you do not specify a schematic. Specify a fake
schematic, or a fake netlist (direct it to an empty file will do
the trick). Then run LVS. LVS will fail, of course, but the
layout netlist will have been generated. In a terminal, move in
the assura run directory. look for .lnn file, it should be here.
this is the vldb (assura binary netlist) extracted from your
layout. issuing the command
vldbToSpice file.lnn > file.sp
will create a spice netlist.

alternatively, you can use vldbToVnl to generate VNL netlist (not very
useful in my opinion, but...)

You can even go further by next using the spice or vldb netlist in
order to achieve a sucessful LVS and the run parasitics extraction,
or create an extracted view (with or without parasitics) that will
allow you to simulate with ADE and to generate netlists in various
formats.

cheers,

stephane

 

Dear my friend stephane:
The direction from you was greatly helpful. but there is no .lnn file
lie in my running directory if LVS failed. I dont know why it was not
generated.

cheer

 

There must be a verilog file and a proper synthesis setup where that gds2 came
from. That would help you better than the assura extraction rules, no ?

 

what have you got there?
please post the log file.

 

Did you try the .ldb file?

If you have neither .ldb nor .lnn, the extract didn't run to
completion, and there should be signs of that in the log file.

I believe the usual way to do an extract-only run is to start
with a normal LVS .rsf, strip the avCompareRules() sections,
and replace avLVS() with:

avDX()
avNX()

-Jay-

 

That's what is supposed, however I tried it and didn't end up with the
expected netlists. It worked though with avLVS()...

 

Hmmm. Just ran a avDX()/avNX() job and it seemed to work just fine
(Assura 3.1.2). No .lnn, I notice, just .ldb. I admit I don't
know what exactly the .lnn is, I've only ever used .ldb for flow
debug, etc.

-Jay-