2 Replies Latest reply on Nov 29, 2011 10:41 AM by bhauge

    Help with exporting "schematic" view to CDL


      We have several 3rd-party IP netlists that we are importing (spiceIn) into Virtuoso OA format. Due to the size and flatness of some of the netlists, we are importing them as "netlist" views. This avoids the need to run "conn2sch" to generate the schematic view, which is where we see the big time hit. We then run a SKILL script to copy the "netlist" views to "schematic" views. This is all outlined in SourceLink Solution ID 11700308.


      The directory structure of these "schematic" views looks strange because they have the file "netlist.oa" under them, plus the master.tag file also references the name "netlist.oa". Despite this, I can export CDL successfully from Virtuoso using the GUI, or by creating a si.env file and running "si -batch -command netlist". However, if I try to export from Calibre, it fails with:


      *WARNING* (DB-270212): dbOpenCellViewByType: Failed to open cellview (cell schematic) from lib (lib) in 'r' mode because cellView database does not exist, or cellview type is not recognized by dbOpenCellViewByType


      I replaced the real cell and library name with "cell" and "lib" to protect the innocent.


      If I rename netlist.oa to sch.oa, and edit master.tag to point to sch.oa, then it works fine.


      It seems pretty clear that it's related to the Cadence data registry entry for the "schematic" view (where it expects to find a file called sch.oa), and I can see why the netlist exporting would be failing. However why does it work fine if I export using the GUI or running "si" manually?


      I can do the rename workaround to get things working with Calibre, but I'm wondering if there's something else that I could do.


      Thanks for the help.



        • 1. Re: Help with exporting "schematic" view to CDL

          Hi Bruce,


          I found a TechNote with some screenshots and descriptions of techniques that might be helpful to getting your si.env file working with the netlist export in your case. Can you get to this link?


          Calibre Netlist Export Setup

          1 of 1 people found this helpful
          • 2. Re: Help with exporting "schematic" view to CDL

            Hi Chris -


            Thanks for the link. Unfortunately, I think the problem lies with the SKILL code that Mentor provides for exporting CDL.


            As I described, in order to bypass running "conn2sch", we import the netlists as "netlist" views, then copy them to "schematic" views. However the file under the "schematic" directory is still called "netlist.oa". The Mentor SKILL code calls these  viewName (for the directory name) and viewType ("netlist" for netlist.oa, "schematic" for sch.oa). From your link, the viewName can be changed, but there is no place on the form to change the viewType, and that is the issue we are having. The SKILL code (mgc_rve_strings->sviewType) always returns "schematic", which means it always expects to find the file "sch.oa". When it doesn't, it fails with the "cellview type is not recognized by dbOpenCellViewByType" error. If we set mgc_rve_strings->sviewType = "netlist" in the CIW, then the CDL netlist is correctly exported.


            So I think our fix will be to define our own SKILL procedure (after the Mentor SKILL code loads) that will first check to see what file is under the "schematic" directory, then set the viewType accordingly.