IBIS Macromodel Task Group Meeting date: 14 September 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, Sigrity Kellee Crisafulli, Celsionix 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 Scott McMorrow, Teraspeed Consulting Group 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 Wenyi Jin, LSI Logic Zhen Mu, Mentor Graphics ------------------------------------------------------------------------ Opens: - Michael Mirmak noted discussion in the last Open Forum meeting about updating the IBIS specification to a Word-like document. He asked TechAmerica for information about costs and timelines associated with this. - Arpad: What is your take on reformatting the specification? Are you willing to entertain this? Should it be discussed here or in the Open Forum? - Michael: As policy goes, BIRDs are submitted and may cover whatever as long as they fit within the template provided. No policy difference whether you choose to refine one concept at a time or a large BIRD changing a whole section. - Arpad: What about making AMI its own spec separated out and formatted differently? - Michael: If you want to do this, submit a BIRD to say you are removing a section (6c) from the spec and include cross references to a new spec (either in that BIRD or another one). Any keywords in brackets should still be within the IBIS specification. - Walter: Restated plan to remove AMI from the spec. - Michael: if just a formatting concern, go to a separate document to include graphics, etc. If the problem is that IBIS in a text format, the cleanest change would be to convert the IBIS specification into a new format, making no technical changes to it and re-approve it. - Walter: Some sections have schematics done with line art. Would it be a requirement that all graphics in the whole specification be updated to a modern format? This is a massive task. - Michael: We are in a race, so if we find that we can update IBIS quickly, the AMI portion could be updated at the same time, and it could be decided at the last minute if AMI becomes separate or part of a reformatted IBIS specification. - Todd: Are the Word and PDF versions of the IBIS specification on the web legal versions? - Michael: Just there for readability. They are all legal versions. Output format can be anything like PDF. Real question is what the input format is, such as Word, Framemaker, etc. He is hoping TechAmerica will have a template that makes sense for us to use to help standardize the process. -------------------------- Call for patent disclosure: - none ------------- Review of ARs: - Authors of Flow BIRD: Correct text in the areas discussed in the meeting - Still open. - 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: 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: Arpad reviewed the IBIS-ATM pending task list spreadsheet and BIRDs that are expected to follow from it: -------------------------------------------------------------------------------- Row 6 - Model_Specific - taken care of in new BIRD - Typos_Format_Value_Default_BIRD_1.txt Row 16 - Will be discussed today. Row 17 - Will ask Walter if he can include his Format info in this new BIRD too. Row 19 - Also addressed in this new BIRD. Row 20 - Turned out to be a false alarm. - Walter: One thing discussed in Open Forum - if we submit a BIRD for one small item, we have many overlapping BIRDs to submit. If we agree in principle about an idea, we could say that all things will get solved in the final edit. - Arpad: Is starting to make comments in his new BIRD that document the ideas of what is being fixed, but doesn't give the exact language change for the spec. - Bob: Would like to add a Description BIRD, wondering if Description could be made optional for everything. - Arpad: Added this as Row 26 in the spreadsheet. Discussion on the Clarifying min/typ/max in IBIS-AMI BIRD: -------------------------------------------------------------------------------- - Arpad: Walter sent a private message about making them min<=typ<=max. Walter wanted to add min < max in the BIRD. This creates a mathematical inconsistency. - Ken: What difference does it make how the sweep works, i.e. as written starting at typ, going up to max, then going closest to min. - Walter: Wording makes sure that typ is always included in the sweep. - John: Doesn't think we need to include text about how the EDA software should do the sweep. - Todd: Purpose is to define the allowed values only. - Arpad: This is covered by the previous description. - Todd: Agrees, the EDA description is not needed. - Bob: Does think the expression needs to be min<=typ<=max, agreeing with Walter. - Arpad: Should we say that min < max? - Walter: Seems silly to allow min=max, but it doesn't matter that much. - Arpad: Under which circumstances do we have defaults for the various formats? This should be addressed in a separate BIRD. Discussion on the IBIS-AMI Typographical Corrections BIRD: -------------------------------------------------------------------------------- - Arpad: New BIRD to clean up inconsistencies in the text. Page 140: Usage becomes required. Type becomes required. Format becomes optional and is deprecated. Examples using Usage, Type, and Format are corrected. - Ambrish: Alarmed by seeing Format without an indication of it being optional - Arpad: There isn't a mechanism to define 'optional' in the specification - Walter: Ambrish is saying that [] are used as optional indicators in other software - Arpad: Doesn't like that [] are used in IBIS keywords. Could use {}. Further comments, please send an email. If I change to using the French brackets {}, should I include the language of preferred and optional language? Will find a way to indicate the preferred/optional language in a mild way. Discussion on including Walter's Format and Values BIRDs in the new BIRD: -------------------------------------------------------------------------------- - Walter: OK with this as long as Label is not included. If treatment of Format is not a consensus, we need to vote on it. - Ken: Plans to comment on Format in an email. Discussion on Walter's Flow BIRD: -------------------------------------------------------------------------------- - Arpad: Would like to see comments on this BIRD. - Bob: Confused on Use_Init_Output boolean as written in the BIRD. - Arpad: Are we allowing people to continue using Use_Init_Output in new models? - Bob: Has anyone ever used this? - Arpad: If someone writes a model without this boolean, nothing will be broken. - Walter: Has been in the crossfire. He is waiting for others to decide on some small points. The model should tell the tool what flow to use. The models are reference flows only. - Ken: Doesn't like special flow for Rx to Tx_Init case. - Walter: These are reference flows only, but it doesn't say that the reference flow is the right flow to use to get the answer. - Ken: Will talk with Walter more this week. - Walter: Ken should discuss issues with Arpad. Minutes ended at 1:07pm PT. Next meeting: 21 Sep 2010 12:00pm PT -------- IBIS Interconnect SPICE Wish List: 1) Simulator directives