IBIS Macromodel Task Group Meeting date: 15 September 2009 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 McGrath, Synopsys David Banas, Xilinx Deepak Ramaswany, Ansoft Donald Telian, consultant Doug White, Cisco Systems * Eckhard Lenski, Nokia-Siemens Networks 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 Pytel, Ansoft Syed Huq, Cisco Systems Syed Sadeghi, ST Micro Ted Mido, Synopsys Terry Jernberg, Cadence Design Systems Todd Westerhoff, SiSoft Vladimir Dmitriev-Zdorov Vikas Gupta, Xilinx Vuk Borich, Agilent * Walter Katz, SiSoft Zhen Mu, Mentor Graphics ------------------------------------------------------------------------ Opens: Bob Ross asked for some discussion of IBIS ISS and the ibischk parser development. Arpad noted that we will have to come back to discussion of IBIS ISS. The document is posted on the IBIS ATM website. Arpad noted that the parser developer asked questions on the parameter descriptions of AMI. Arpad and Walter both responded to the developer. Michael Mirmak said that the question is now closed. The developer is treating Description as required on reserved parameters. Examples in the specification will need to be fixed. Michael is expecting parser code delivery soon. Ambrish asked when parser code will be available for the general public. Michael said it will be reviewed by the parser committee first. An executable will follow soon after. Arpad reported he had offline discussion with Kumar and Walter about digital versus analog input to GetWave. There is resolution on the issue. Kumar agrees with Walter as long as the GetWave function is not bit-pattern dependant. Kumar questioned if this type of buffer exists in real life. Arpad asked Michael to look into this. Michael does not have any info on this yet. -------------------------- Call for patent disclosure: - No one declared a patent. ------------- Review of ARs: - Walter send his email proposing AMI flow changes - done - Walter send Init_Return_Just Buffer_Equalization presentation to Mike L - done - Mike L post presentations from Walter to web page - done - Mike change web page to make items easily linkable - in progress - 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: 1) Discuss Walter's "Digital flow" proposal he posted in an email on the ATM reflector on 9/8/2009 Walter showed a presentation titled "Analog and Digital Flows Give Same Answer When Tx is LTI." He described the analog versus digital flow. Arpad noted that he has a hard time with the description of analog versus digital. It seems more like LTI versus non-LTI. Michael M. noted that digital flow is digital data in and digital data out in a left to right pipeline. The analog flow is more of an order of operations. Walter stated that the DataGenerator in both cases is similar to a SPICE PWL source. Ambrish noted that the difference is the input to the Tx GetWave. Arpad suggested the terminology change to Original Flow and Proposed Flow. Walter proposed earlier that the DataGenerator source transition from -0.5V to +0.5V with a point in between at 0V signaling the transition. Walter's next slide noted that when the transmitter is LTI, the order of the transmitter and channel blocks can be interchanged, so the two flows give the same results. Arpad showed a block diagram for the current AMI flow and one for the proposed flow. Walter asked Arpad to change the text of step 4 in the second slide to be the same in both slides "Input bit stream and unit pulse". If you don't have Duty Cycle Distortion in the stimulus, these steps are the same. Walter noted that the 5.0 spec didn't make it clear how to handle the stimulus. Walter brought up another presentation titled "New Reference Flow". The IBIS 5.0 original flow has the side effect of not being able to handle Use_Init_Output correctly. Walter proposed a new reserved parameter called Init_Returns_Filter that is optional and defaults to False. He showed a proposed reference flow when Tx and Rx AMI_GetWave exist. Arpad asked which convolutions are done by the model and which are done by the tool. Walter responded that all the convolutions are done by the tool in this flow when the model tells the tool to do the convolution. Ambrish asked if Walter was saying that the input to Rx GetWave can be sampled data and simulation data, but it can not be an input to Tx GetWave. In Walter's flow, Tx GetWave can only be a 'digital stimulus'. Arpad asked if Init_Returns_Filter is the same parameter discussed last week. Walter responded that it is, now with an official name. Walter noted that he can not join the meeting next week. ARs: - Walter to send his presentation to Mike LaBonte. - Arpad to add flow changes to his block diagram presentation and send to Mike LaBonte. Next meeting: 22 Sep 2009 12:00pm PT -------- IBIS Interconnect SPICE Wish List: 1) Simulator directives