IBIS Macromodel Task Group

Meeting date: 02 March 2010

Members (asterisk for those attending):
  Adge Hawes, IBM
* Ambrish Varma, Cadence Design Systems
* Anders Ekholm, Ericsson
* Arpad Muranyi, Mentor Graphics Corp.
  Barry Katz, SiSoft
* Bob Ross, Teraspeed Consulting Group
  Brad Brim, Sigrity
  Brad Griffin, Cadence Design Systems
  Chris Herrick, Ansoft
  Chris McGrath, Synopsys
* Danil Kirsanov, Ansoft
  David Banas, Xilinx
  Deepak Ramaswany, Ansoft
  Donald Telian, consultant
  Doug White, Cisco Systems
* Eckhard Lenski, Nokia-Siemens Networks
  Eckhard Miersch, Sigrity
  Essaid Bensoudane, ST Microelectronics
  Fangyi Rao, Agilent
  Ganesh Narayanaswamy, ST Micro
  Gang Kang, Sigrity
  Hemant Shah, Cadence Design Systems
  Ian Dodd, consultant
  Jerry Chuang, Xilinx
  Joe Abler, IBM
* John Angulo, Mentor Graphics
  John Shields, Mentor Graphics
  Ken Willis, Cadence Design Systems
  Kumar Keshavan, Sigrity
  Lance Wang, Cadence Design Systems
  Luis Boluna, Cisco Systems
  Michael Mirmak, Intel Corp.
* Mike LaBonte, Cisco Systems
  Mike Steinberger, SiSoft
  Mustansir Fanaswalla, Xilinx
  Patrick O'Halloran, Tiburon Design Automation
  Paul Fernando, NCSU
  Pavani Jella, TI
  Radek Biernacki, Agilent (EESof)
  Randy Wolff, Micron Technology
  Ray Komow, Cadence Design Systems
  Richard Mellitz, Intel
  Richard Ward, Texas Instruments
  Samuel Mertens, Ansoft
  Sam Chitwood, Sigrity
  Sanjeev Gupta, Agilent
  Shangli Wu, Cadence Design Systems
  Sid Singh, Extreme Networks
  Stephen Scearce, Cisco Systems
  Steve Kaufer, Mentor Graphics
  Steve Pytel, Ansoft
  Syed Huq, Cisco Systems
  Syed Sadeghi, ST Micro
  Ted Mido, Synopsys
  Terry Jernberg, Cadence Design Systems
  Todd Westerhoff, SiSoft
  Vladimir Dmitriev-Zdorov, Mentor Graphics
  Vikas Gupta, Xilinx
  Vuk Borich, Agilent
* Walter Katz, SiSoft
  Zhen Mu, Mentor Graphics

------------------------------------------------------------------------
Opens:

- Mike: Some recent unposted minutes files may be lost
  - Some files carried over through an operating system change are encrypted
  - Mike will try to recover the files

--------------------------
Call for patent disclosure:

- No one declared a patent.

-------------
Review of ARs:

- Walter to email latest BIRD draft to group
  - Done

- Mike to convert Walter's BIRD to PDF and post to web
  - Done

- Arpad: Write a clarification BIRD to discuss accuracy issues related to the 
  various AMI clock_tick algorithms in an IBIS-AMI DLL
  - TBD

- Todd: Update the BIRD for IBIS S-parameter box based on feedback from discussion
  - No update

- Arpad:  Write parameter passing syntax proposal (BIRD draft)
          for *-AMS models in IBIS that is consistent with the
          parameter passing syntax of the AMI models
          - TBD

- TBD:    Propose a parameter passing syntax for the SPICE
          - [External ...] also?
          - TBD

- Arpad:  Review the documentation (annotation) in the macro libraries.
          - Deferred until a demand arises or we have nothing else to do

-------------
New Discussion:

Bob: Advice given as IBIS chair:
- Everything has a cost/schedule/performance tradeoff
  - Cost is restrained
  - Performance is key
    - The syntax must be technically robust
    - The description must be publication quality
- We have to make rational technical decisions
- But we don't have the needed clarity
- We need to decide:
  - Time constraint
  - Feature set
- Arpad: It's not that we are dissatisfied with Walter's work
- Walter: It would be valuable to have a writer with technical competence
  - We are not quite ready for a parser developer to use it
  - EDA vendors need to make that judgment
  - We need to set a date to have it ready by
  - IC vendors are anxious to move forward on this
  - I'm preparing jitter and analog amendments
- Bob: Disagree with most of those points
- Walter: Not saying this document is ready for prime time
- Bob: The process is not about EDA vendors
  - It must be specification quality
- Walter: Agree with that
- Bob: We should not bind to a schedule
  - It could be submitted today, but there would be much discussion
- Walter: We should all make recommendations on how to go forward
  - For now we can discuss recent technical emails
- Arpad: We probably agree the BIRD is not ready for submission
  - We can discuss hiring someone for technical writing
- Mike: Maybe a developer could be hired to look at it
  - That was what derailed us last time
- Bob: We can discuss this for 1/2 hour in the next open forum
  - Everyone has an interest in this
- Arpad: Agree with Mike's idea
  - It would help to hear from outsider spec users

Bob: I have received private concerns on this BIRD:
- This will be a consideration for the editorial committee
- Some features may have to be stripped off to make a cut line
- Mike: Anonymous concerns might be OK, but not secret ones
- Bob: For example, someone may be using the deprecated Table keyword
- Walter: We have asked if anyone knew of anyone using Tables
  - That should be public
- Arpad: Why would that have to be private?
- Bob: This is a legitimate vendor, that's all I can say
- Walter: Are they claiming the models will work in any EDA tool?
- Bob: Any vendor can donate a technical writer's time
  - But the technical committee has ultimate control

Walter showed amendment suggestions sent by email:
- A new section tries to answer "What is a parameter?"
  - What know what a parameter tree is
  - A branch is a parameter if it has one of a given list of leaves
- Ambrish: Can branches not be parameters?
- Walter: DFE taps would not be parameters passed to the DLL
  - In the AMI file it would have keywords to make it a parameter
- Ambrish: So "Tap" is not passed to the model?
- Walter: I have an example below
- Bob: It is good to clarify this

Walter: Changes were made to Default
- This handles the 5.0 spec completely
- Bob: Can we have Value and Default together?

Walter showed the txtaps example mentioned above:
- Ambrish: Every branch is an AMI parameter
- Mike: A branch then is a parameter if it has any leaf of a known type
- Ambrish: Can framis for example have subparameters

Walter: BNF can describe only a context insensitive grammar:
- The AMI file is context sensitive
- I provided a template AMI file with limited BNF-like syntax
- Not sure if description of tap is OK
- Bob: Agree BNF is not the way to go
  - This format should not be in the spec
  - IBIS is context sensitive
  - BNF can be helpful
  - It can't be the formal definition
  - It should not be in this BIRD
- Walter: Not prepared to remove it
- Arpad: Concerned that we don't have a good description without the BNF
  - Not ready to decide on this yet

Next meeting: 9 Feb 2009 12:00pm PT

--------

IBIS Interconnect SPICE Wish List:

1) Simulator directives
