[ibis-macro] Minutes from the 17 Mar 2015 ibis-atm meeting
- From: Mike LaBonte <mike@xxxxxxxxxxx>
- To: 'IBIS-ATM' <ibis-macro@xxxxxxxxxxxxx>
- Date: Wed, 18 Mar 2015 10:28:38 -0400
Minutes from the 17 Mar 2015 ibis-atm meeting are attached. Documents
shown in the meeting are uploaded to the IBIS-ATM work archive:
*DATE* AUTHOR
<http://www.eda.org/ibis/macromodel_wip/archive-author.html>
ORGANIZATION <http://www.eda.org/ibis/macromodel_wip/archive-org.html>
TITLE <http://www.eda.org/ibis/macromodel_wip/archive-title.html> FORMATS
17-MAR-2015 Michael Mirmak Intel Corporation IBIS-AMI and Direction
Decisions part 3 (zip
<http://www.eda.org/ibis/macromodel_wip/archive/20150317/michaelmirmak/IBIS-AMI_and_Direction_Decisions_part_3.zip>)(pptx
<http://www.eda.org/ibis/macromodel_wip/archive/20150317/michaelmirmak/IBIS-AMI%20and%20Direction%20Decisions%20part%203/IBIS-AMI-and-direction-indication-part3.pptx>)
17-MAR-2015 Randy Wolff Micron Technology C_comp Model Using
IBIS-ISS
BIRD draft 5 (zip
<http://www.eda.org/ibis/macromodel_wip/archive/20150317/randywolff/C_comp_Model_Using_IBIS-ISS_BIRD_draft_5.zip>)(docx
<http://www.eda.org/ibis/macromodel_wip/archive/20150317/randywolff/C_comp%20Model%20Using%20IBIS-ISS%20BIRD%20draft%205/C_Comp_Model_BIRD_5.docx>)
Mike
IBIS Macromodel Task Group
Meeting date: 17 March 2015
Members (asterisk for those attending):
Altera: David Banas
ANSYS: * Dan Dvorscak
* Curtis Clark
Avago (LSI) Xingdong Dai
Cadence Design Systems: * Ambrish Varma
Brad Brim
Kumar Keshavan
Ken Willis
eASIC * David Banas
Ericsson: Anders Ekholm
IBM * Steve Parker
Intel: * Michael Mirmak
Keysight Technologies: Fangyi Rao
* Radek Biernacki
Nicholas Tzou
Maxim Integrated Products: Hassan Rafat
Mentor Graphics: * John Angulo
* Arpad Muranyi
Micron Technology: * Randy Wolff
Justin Butterfield
QLogic Corp. James Zhou
Andy Joy
eASIC Marc Kowalski
SiSoft: * Walter Katz
Todd Westerhoff
* Mike LaBonte
Synopsys Rita Horner
Teraspeed Consulting Group: Scott McMorrow
Teraspeed Labs: Bob Ross
(Note: Agilent has changed to Keysight)
The meeting was led by Arpad Muranyi.
------------------------------------------------------------------------
Opens:
--------------------------
Call for patent disclosure:
- None
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Review of ARs:
- Michael M send list email about directionality issues.
- Done.
- Michael M send AMI Direction presentation to Mike L for posting
- Posted now.
- Walter and Randy produce C_comp BIRD.
- Randy: Some progress, but we need to resolve issues about parameters.
- Arpad to review IBIS specification for min max issues.
- In progress.
-------------
New Discussion:
AMI Directionality:
- Michael M showed IBIS-AMI and Direction Decisions
- Michael M: There has been list discussion since this was sent yesterday.
- slide 4:
- Michael M: There are two options for I/O AMI models:
- A: Unified or separate DLLs.
- B: Separate DLLs only.
- Ambrish: It is for the DLL to decide.
- Radek: "A" is already permitted.
- Michael M: They are in the wild now?
- Walter: Michael M wants separate AMI files for the TX and RX.
- We seem to want to have separate AMI files.
- How would the tool know which parameters are for which if they are merged?
- Arpad: "A" gives more flexibility.
- slide 5:
- Michael M: Two options for AMI files for I/O:
- A: Unified or separate AMI files.
- B: Separate AMI files only.
- Walter: It's OK to have RX parameters in a TX AMI file.
- Ambrish: We gain nothing by mandating a unified AMI file for an I/O.
- Radek: Agree, I'm inclined toward "B".
- Arpad: Does "B" imply only separate DLLs too?
- Radek: A single value parameter would pass to the DLL but have no user
options.
- Walter: I said one DLL with 2 AMI files requires 2 Executable lines.
- For an I/O the tool would have to figure out which Executable is TX and
RX.
- Michael M: We need clarity on this before we work on syntax.
- John: The user could choose which Executable line to use.
- Ambrish: They point to the same DLL.
- John: A parameter is needed to say if an I/O is TX or RX.
- Michael M: We have that in the proposal.
- Radek: There could be separate [Algorithmic Model] sections for TX and RX.
- Michael M: We need a foolproof association that is not ambiguous.
- Ambrish: There is no way to know which DLL goes with which AMI.
- Radek: The AMI can be checked for Reserved_Parameter keywords.
- Michael M: This would be a check for conflicting parameter types?
- Radek: Yes.
- Michael M: I am proposing unambiguous parameters for this.
- John is proposing an AMI file that uses only parameters not specific to TX
or RX.
- John: For an I/O a direction parameter is necessary.
- Otherwise we have only a cross check.
- Walter: We can't check the AMI against the DLL.
- We can check the AMI against the IBIS that calls it.
- John: We can't stop people from having any Model_Specific parameters they
want.
- Michael M: The parameter Walter asks for has been in the BIRD all along.
AR: Michael M update AMI Directionality BIRD
C_Comp enhancements:
- Randy showed a C_Comp Model Enhancements BIRD draft.
- Randy: This has [C_comp Model] and [End C_comp Model].
- It gives subckt info including the number of terminals.
- It overrides any other C_comp keywords.
- The "Parameter' sub-parameter should be consistent with the interconnect
BIRD.
- It just passes Corner values, no other formats.
- Walter: We need just Corner values.
- Typ-only should be allowed.
- Randy: A Touchstone or ISS file can be used.
- This tries to discourage using node 0.
- It can be a parallel or series model.
- Arpad: Can this be combined with a series C_comp?
- In the series model the input could connect to "A_signal".
- Are only those 4 reference voltages allowed? How about GND?
- Randy: It uses the same connections a model has available.
- Arpad: It would be best to limit to those four.
- Randy: It can be used as a differential model.
- There are rules about terminal counts.
- It might be used for differential pins.
- Mike L: There should be an example of that to be sure.
- Walter: We could also use two single ended pins differentially.
- Mike L: A protocol to say where true and complement are connected is needed.
- Walter: That is defined in this BIRD.
- Randy: The rules of precedence are explicit.
- Walter: That is needed.
PAM4:
- Walter showed a draft PAM4 BIRD.
- Walter: This allows a model to say if it is NRZ or PAM4.
- The mapping of symbols to levels can be given.
- The center threshold is 0 for NRZ.
- The model can return threshold values.
- The outer eye offset supports timing offsets.
- Someone brought up duobinary.
- David: We should not block that.
- Walter: This doesn't block it, it just doesn't specify it.
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Next meeting: 24 Mar 2015 12:00pm PT
-------------
IBIS Interconnect SPICE Wish List:
1) Simulator directives
Other related posts:
- » [ibis-macro] Minutes from the 17 Mar 2015 ibis-atm meeting - Mike LaBonte
