Encounter DEF file export

This sounds like the DFII techfile and the technology LEF file you are using in Encounter are not compatible. The via definitions in both DFII and LEF need to match. You'll need to have your design kit provider fix the techfiles so that they are compatible.

 Rayz,

A more typical way to get your design from Encounter into DFII is by streaming out of Encounter and then streaming in to DFII. Of course, you will need to have your libraries already in DFII. (Std cell, RAM, IO, etc.) You could also try streaming out of Encounter with the -merge option, which will include the GDS layouts, and then you may not need to have them in DFII already. Streaming out of Encounter requires a gds layer map. Post back if you need more help with this.

- Kari 

I don't understand why people prefer to use GDSII over DEF. I find DEF a much better way to import the data into DFII. When importing with DEF, all of the objects retain properties such as cell names on instances and net names on routes. This is very helpful if anything ever needs to be debugged in  LVS or if you are investigating ECOs, etc. If you use GDSII, all of that data gets lost.

 Scrivner,

That's a really good point. I don't recall now why I started preferring GDSII to DEF, but I'm glad it works well for you and that you had the experience to answer the question from Rayz. These days, it's not an issue for me because I do pretty much everything in Encounter. DFII just becomes the chip assembly area for final GDS.

- Kari

 you can retain some of the prop. (inst name, net name..) by adding some key words to the SOCE stream out mapping table.  It is a little tricky to get the DFII tech file to match with the P&R vias defination.  That is why GDSII is a prefered way that DEF.

 li siang

Hi All,

I  am trying to import DEF (5.4) file into DFII ( ic5141) am not getting data Corrrectly.

I am facing below problems .

1)  In Def some of the Cells are in r90 orientation,When importing in to DFII am retaining orientation but cell  is misplacing

          (In  def it is considering lower lef co-ordinate but in DFII  it is considering orgin as reference ).

2)  In DFII Environment  missing  PNR placed VIAS .

 please help me on this . If Possible send me the procedure and  what are the required files need to set .

Thnks,

-SURA 

 Hi Kari,

 I am trying to export GDS file from encounter into DFII. I have cds2gds.map and gds2cds.map, they are pretty similar, which one should I use? also, I found the map files are not acceptable by encounter while doing export. From the document, it seems encounter's layer mapping file has the different format than the DFII mapping layer format.

 THis is from encounter,

METAL1    NET           1        0
METAL1    SPNET         999      0
METAL1    PIN           1000     0
METAL1    LEFPIN        2000     0
METAL1    FILL          3000     0
METAL1    VIA           4000     0
METAL1    VIAFILL       5000     0
METAL1    LEFOBS        10000    0
NAME      METAL1/NET    20000    0

 And this is from DFII,

#Cadence layer    Cadence layer    Stream layer    Stream data
#name             purpose          number          type
#
metal             drawing          13,10,18        0-63
poly              drawing          40              0

so I could not do export and import correctly, any suggestions?

THanks a lot!

 Hi,

It may have been better to start a new thread with this question, coffeelox - since you're looking to streamOut of Encounter and not DEFin to DFII, as the original poster was. Anyway, I'll take a stab at it...

Yes, the format of the layer map file for Encounter's streamOut is completely different from a DFII gds map file. It's usually a lot shorter, since Encounter only deals with metal layers. You may need to create the Encounter gds map file if it was not part of the tech data delivered by the foundry. The DFII gds map file is usually part of the deliverables from the foundry. I don't know what the difference is between the two you have (cds2gds and gds2cds).

It looks like you've already found the format for the Encounter map file in the User Guide. Also take a look at the streamOut command in the Text Command Reference. You'll want to specify the map file in this command. You will get a gds2 file that you can read into DFII.

When you read the Encounter GDS file into DFII, you'll need to use the DFII gds map file.

I'm not sure if this completely answers your question, but I hope it helps.

- Kari

Hi Kari,

 Thanks a lot for your quick response! It helped me a lot on my tapeout. But I still have further questions about these map files.

encounter uses the map file has format totally different from DFII uses. In encounter, it uses NET, SPNET, LEFPIN, LEFOBS, etc, but in cadence, it uses drawing, pin, etc. Now I have the cds2gds.map file which is used in DFII. How can I modify this file to be used in encounter?

 Thanks a lot!

James 

Hi James,

You wouldn't so much modify the DFII map file to get the Encounter map file, as you would create the Encounter map file from scratch and just use the GDS layer and datatype numbers from the DFII map file. The Encounter map file only needs the layers that are defined in your LEF file, usually just the metal and via layers. These usually correspond to the "drawing" purpose in the DFII map file. But you may also have metal fill (as an example), which may or may not be a different purpose or even a different layer altogether. I've seen DFII techfiles that define these things several different ways, so it really depends on your technology.

The Encounter User Guide has a chapter called "Importing and Exporting Designs" - read the section near the end about the map file format. Take a stab at creating it, stream the GDS into DFII, and see if everything is there like it should be. If not, you may have to go back and add some things. 

Here's a quick example for just a couple of layers that may help: (the colums are: lef layer name, Encounter object type, GDS layer #, GDS datatype #)

M1              NET             31              0
M1              SPNET           31              0
M1              FILL            31              1
M1              PIN             31              0
VIA1            VIA             51              0
M2              NET             32              0
M2              SPNET           32              0
M2              FILL            32              1
M2              PIN             32              0

- Kari