• Skip to main content
  • Skip to search
  • Skip to footer
Cadence Home
  • This search text may be transcribed, used, stored, or accessed by our third-party service providers per our Cookie Policy and Privacy Policy.

  1. Community Forums
  2. Digital Implementation
  3. Encounter 8.1 vs 9.1 sdf generation

Stats

  • Locked Locked
  • Replies 8
  • Subscribers 93
  • Views 16932
  • Members are here 0
This discussion has been locked.
You can no longer post new replies to this discussion. If you have a question you can start a new discussion

Encounter 8.1 vs 9.1 sdf generation

MzQuarter
MzQuarter over 14 years ago

Hi,

I've used Encounter 8.1 for past projects to generate sdf back-annotation for simulation and it worked great. Now we've moved to Encounter 9.1, but the exact same 8.1 encounter project reloaded in 9.1 gives different results. First of all, the middle field ("typical", my guess) is no longer present, and when I load the sdf in a simulator the delays are all taken as 0 (no delays).  Second, the delays for interconnect are different, and quite often 0. Another difference I noticed is that in 8.1 the value triplets were always the same (which I thought odd), but not in encounter 9.1.

What am I missing? I'm almost sure it's just a setting, but I can't see where or how.

Thanks.

--------------------------------------------------------------------------------
Encounter 8.1:

(INTERCONNECT I_NCS U134/A (0.0037:0.0037:0.0037) (0.0037:0.0037:0.0037))
(INTERCONNECT I_SCLK Q_TRANSACTIONCOMPLETE_REG/CKN (0.0045:0.0045:0.0045) (0.0045:0.0045:0.0045))

Encounter 9.1:

(INTERCONNECT I_NCS U134/A  (0.003::0.004) (0.003::0.004))
(INTERCONNECT I_SCLK Q_TRANSACTIONCOMPLETE_REG/CKN  (0.000::0.000) (0.000::0.000))

  • Cancel
Parents
  • MzQuarter
    MzQuarter over 14 years ago

    Hi diablo,

    Here is what I do through the GUI, with a little more detail, (same for both versions).

    1- Start encounter
    2- Restore design from an encounter format
    3- Do RC extract (simplest kind, not sign-off)
    4- Calculate timing

    It translates to the following commands in the log file, after loading the project:

    Encounter 8.1: 
    <CMD_INTERNAL> isExtractRCModeSignoff
    <CMD> extractRC
    <CMD> delayCal -sdf SPI_Demo_8.1.sdf -idealclock

    Encounter 9.1:
    <CMD> extractRC
    Extraction called for design 'SPI_Demo' of instances=169 and nets=130 using extraction engine 'preRoute' .
    <CMD> write_sdf -ideal_clock_network SPI_Demo_9.1.sdf

    So no, it doesn't specify the views :(.  I looked in the command documentation and found the info on -max/min/typ_view and the -view switches. It looks like what I'm looking for, because the -view switch mentions it doesn't populate the typ slot. This is great news, but I have 3 other questions:

    1- The commands require a "viewName" argument. What's this and how do I know what to give as argument? The documentation is not very detailed on this point.
    2- The switches are said to be used in Multi Mode Multi Corner analysis, but I haven't done this yet (unless the Extract RC does this without telling me). I'm pretty sure it should be standard verification for sign-off, but for now I just want a quick'n dirty annotation file. Do I really have to do corner analysis at this point?
    3- Can you set this option in the GUI? Everything will end up in a script, but it's always nice to have GUI handy.

    Thanks

     

    • Cancel
    • Vote Up 0 Vote Down
    • Cancel
Reply
  • MzQuarter
    MzQuarter over 14 years ago

    Hi diablo,

    Here is what I do through the GUI, with a little more detail, (same for both versions).

    1- Start encounter
    2- Restore design from an encounter format
    3- Do RC extract (simplest kind, not sign-off)
    4- Calculate timing

    It translates to the following commands in the log file, after loading the project:

    Encounter 8.1: 
    <CMD_INTERNAL> isExtractRCModeSignoff
    <CMD> extractRC
    <CMD> delayCal -sdf SPI_Demo_8.1.sdf -idealclock

    Encounter 9.1:
    <CMD> extractRC
    Extraction called for design 'SPI_Demo' of instances=169 and nets=130 using extraction engine 'preRoute' .
    <CMD> write_sdf -ideal_clock_network SPI_Demo_9.1.sdf

    So no, it doesn't specify the views :(.  I looked in the command documentation and found the info on -max/min/typ_view and the -view switches. It looks like what I'm looking for, because the -view switch mentions it doesn't populate the typ slot. This is great news, but I have 3 other questions:

    1- The commands require a "viewName" argument. What's this and how do I know what to give as argument? The documentation is not very detailed on this point.
    2- The switches are said to be used in Multi Mode Multi Corner analysis, but I haven't done this yet (unless the Extract RC does this without telling me). I'm pretty sure it should be standard verification for sign-off, but for now I just want a quick'n dirty annotation file. Do I really have to do corner analysis at this point?
    3- Can you set this option in the GUI? Everything will end up in a script, but it's always nice to have GUI handy.

    Thanks

     

    • Cancel
    • Vote Up 0 Vote Down
    • Cancel
Children
No Data

Community Guidelines

The Cadence Design Communities support Cadence users and technologists interacting to exchange ideas, news, technical information, and best practices to solve problems and get the most from Cadence technology. The community is open to everyone, and to provide the most value, we require participants to follow our Community Guidelines that facilitate a quality exchange of ideas and information. By accessing, contributing, using or downloading any materials from the site, you agree to be bound by the full Community Guidelines.

© 2025 Cadence Design Systems, Inc. All Rights Reserved.

  • Terms of Use
  • Privacy
  • Cookie Policy
  • US Trademarks
  • Do Not Sell or Share My Personal Information