[ibis-macro] Minutes for August ibis-atm meetings
- From: Mike LaBonte <mike@xxxxxxxxxxx>
- To: ibis-macro@xxxxxxxxxxxxx
- Date: Fri, 12 Aug 2011 12:09:19 -0400
Minutes from the Aug 2 and Aug 9 ibis-atm meetings are attached.
Mike
IBIS Macromodel Task Group
Meeting date: 02 Aug 2011
Members (asterisk for those attending):
Agilent: Fangyi Rao
Radek Biernacki
Altera: * David Banas
Ansys: Samuel Mertens
* Dan Dvorscak
* Curtis Clark
Arrow Electronics: Ian Dodd
Cadence Design Systems: Terry Jernberg
* Ambrish Varma
Celsionix: Kellee Crisafulli
Cisco Systems: * Mike LaBonte
Ashwin Vasudevan
Syed Huq
Ericsson: Anders Ekholm
IBM: Greg Edlund
Intel: Michael Mirmak
LSI Logic: Wenyi Jin
Mentor Graphics: * John Angulo
Zhen Mu
* Arpad Muranyi
Micron Technology: Randy Wolff
NetLogic Microsystems: Ryan Couts
Nokia-Siemens Networks: * Eckhard Lenski
Sigrity: Brad Brim
Kumar Keshavan
* Ken Willis
SiSoft: * Walter Katz
* Todd Westerhoff
Doug Burns
Snowbush IP: Marcus Van Ierssel
ST Micro: Syed Sadeghi
Teraspeed Consulting Group: Scott McMorrow
Bob Ross
TI: Casey Morrison
Alfred Chong
Vitesse Semiconductor: Eric Sweetman
Xilinx: Mustansir Fanaswalla
The meeting was lead by Arpad Muranyi
------------------------------------------------------------------------
Opens:
- Mike: List email was suspended since last night
- Position at Cisco eliminated, but will continue IBIS as long as possible
- Can still administer email and web page
--------------------------
Call for patent disclosure:
- None
-------------
Review of ARs:
- Arpad rework BIRD 137
- Done
- Arpad rework BIRD 127 to accommodate NULL pointer conventions
- Done
- Ken update backchannel slides and send to Mike for posting
- Already done
- An update on training done parameter will be done
-------------
New Discussion:
Arpad: We should schedule time for Ken to present his new BIRD draft
- Ken: 2 weeks from now would be good
BIRD 137:
- Arpad: There are 3 options for empty strings:
- Null pointer, pointer to null, or root name only
- We need to decide
- Arpad: For AMI_Init we can require a valid string with root name
- Walter: I think that was the general consensus at the last meeting
- Ambrish: Recommend changing root name from "dll" to something else
- Mike: How about "AMI_parameters_in"?
- Arpad: It now has an example of an empty root name only string
- Ambrish: It could be changed to MySampleAMI
- Radek: It could be MySample1, MySample2, etc.
- Put a period after "name of the parameter tree" to make it clear.
- Arpad: I added a rule that AMI_parameters_in/out must not be in quotes
- Walter: The last sentence of item 1 is not clear
- Individual values can contain whitespace if they are strings
- Radek: Correct
- Arpad: Added actions if AMI_Init wants to return nothing
- Are the first 3 options OK or do we want to require root name (#4)
- Ambrish: All 4 are OK
- Radek: We don't need all that flexibility
- The EDA platform should be able to enforce
- Curtis: Last week we decide not to leave models behind
- No matter what the spec requires EDA tools can be tolerant
- Arpad deleted actions 1 to 3
- Curtis: We can get rid of "non-zero"
- Arpad made the same changes for AMI_GetWave
- Radek: Message strings should not be empty
- They should be either real messages or null pointers
- Curtis: Agree
BIRD 135:
- Arpad: Added clarification of empty string literal to point 8
- This is scheduled for a vote Friday
- Curtis: Does the spec say identifiers must begin with lowercase?
- Arpad: No
- Arpad's change was accepted for submission to Open Forum as BIRD 135.1
Revisiting BIRD 137:
- Walter: The last sentence on pg 186 item 1 has poor English
- Curtis: We can eliminate the sentence
- We decide not to allow those
- Arpad showed an email from Walter
- Walter: We allow spaces in String parameters
- Arpad: The original spec does not allow whitespace
- Walter: We will have to change it in both places
- Radek: We can say the exception is for string literals
AR: Arpad update BIRD 137
We approved submission of BIRD 137.1 with changes to Open Forum
Supporting_Files:
- Walter: This was discussed with Fangyi
- Two types are needed
- Files always needed by DLL
- Specific to the particular model
- Would be delivered in same directory as DLL
- EDA tool might put first type in a shared space
- Disagree with Fangyi on vendor acceptance of BIRD 121 file structure
- A third party involved in this is on vacation
Walter: No need to discuss analog buffer now
Walter: Jitter could be on agenda for next week
- Arpad: Vladimir sent email suggestions, but got no response
- Walter: I can answer that
- Arpad: We need to cover Tx_DCD
- Walter: We can do that next week
Walter: Dependency Table functionality has not changed
- Rewritten to use Table now that that is cleaned up
Meeting ended.
-------------
Next meeting: 09 Aug 2011 12:00pm PT
Next agenda:
1) Task list item discussions
-------------
IBIS Interconnect SPICE Wish List:
1) Simulator directives
IBIS Macromodel Task Group
Meeting date: 09 Aug 2011
Members (asterisk for those attending):
Agilent: * Fangyi Rao
* Radek Biernacki
Altera: David Banas
Ansys: Samuel Mertens
* Dan Dvorscak
* Curtis Clark
Arrow Electronics: Ian Dodd
Cadence Design Systems: Terry Jernberg
* Ambrish Varma
Celsionix: Kellee Crisafulli
Cisco Systems: * Mike LaBonte
Ashwin Vasudevan
Syed Huq
Ericsson: Anders Ekholm
IBM: Greg Edlund
Intel: Michael Mirmak
LSI Logic: Wenyi Jin
Mentor Graphics: * John Angulo
Zhen Mu
* Arpad Muranyi
* Vladimir Dmitriev-Zdorov
Micron Technology: Randy Wolff
NetLogic Microsystems: Ryan Couts
Nokia-Siemens Networks: * Eckhard Lenski
QLogic Corp. * James Zhou
Sigrity: Brad Brim
* Kumar Keshavan
Ken Willis
SiSoft: * Walter Katz
* Todd Westerhoff
Doug Burns
Snowbush IP: Marcus Van Ierssel
ST Micro: Syed Sadeghi
Teraspeed Consulting Group: Scott McMorrow
* Bob Ross
TI: Casey Morrison
Alfred Chong
Vitesse Semiconductor: Eric Sweetman
Xilinx: Mustansir Fanaswalla
The meeting was lead by Arpad Muranyi
------------------------------------------------------------------------
Opens:
- James Zhou introduction:
- Principal SI engineer at QLogic
- Serdes and DDR3 simulations
- Developing network storage ASICs and other network products
- Created IBIS with home grown programs
- Must provide models to customers, but using vendor provided AMI models
--------------------------
Call for patent disclosure:
- None
-------------
Review of ARs:
AR: Arpad update BIRD 135
- Done
AR: Arpad update BIRD 137
- Done
AR: Arpad update BIRD 127
- Done last week
-------------
New Discussion:
Arpad showed BIRD 137
- Arpad quickly described modifications
- Radek: It looks good
- Arpad: This has a single argument, which is not true
- Walter had suggested new wording
- Radek: This looks looks good
- Bob: Agree
- Walter: One from each column could go in parentheses
- Bob: A note at the end should describe the changes
- Say it is in response to BIRD 132
- Arpad: Can this be submitted?
- Ambrish: Would like more time to review
- Walter: We should submit
- The next meeting is in two weeks
- We can submit after the next ATM meeting
Walter showed "Components of an IBIS-AMI Simulation"
- Slide 3
- The EDA tool generates the stimulus to TX GetWave
- This must include jitter
- IBIS 5.0 TX_Jitter specifies one of 4 jitter types
- BIRD 123 added DCD, Rj, Sj+frequency
- Walter showed BIRD 123 with comments:
- Clarification of DCD
- Vladimir: This is more clear
- Bob: Is there a need for Usage Out here?
- Walter: We have not seen any
- Walter: Rj is Gaussian
- Vladimir had commented about "uncorrelated"
- This is just a random distribution
- Other spectral distributions could be described
- Vladimir: The effect of jitter does depend on distribution
- It could be uncorrelated or highly correlated
- We should think about spectral distributions if this doesn't meet our
needs
- Walter: Some people call it bounded or deterministic jitter
- Sj + Rj covers most needs
- Dual Dirac and DjRj are forms of Sj
- Kumar: DjRj is a post-process, Sj is time domain
- Walter: There is C code that can generate Sj
- Dual Dirac, DjRj and Table are not mathematically precise
- Vladimir: Jitter amplification is very different for correlated jitter
- Phase changes slowly from bit to bit when uncorrelated
- Walter: Two effects
- 1) Data dependent jitter could affect amplification
- Out of the context of what we can do
- 2) Complex patterns could be amplified differently
- Up to the EDA tool to generate these at TX input
- Vladimir: I can provide examples
- Fangyi: Kumar is talking about autocorrelation
- People look at the spectrum of the jitter trend on the scope
- There is a flat noise floor
- That is plugged into random jitter
- Walter added this to BIRD 123
- Todd: Someone said uncorrelated jitter is Gaussian?
- Vladimir: Gaussian jitter could be correlated or uncorrelated
- It can be characterized by spectral distribution
- Or it can be described statistically in time domain
- Walter: In statistical there is no time domain
- We have to know where the clock is
- Must combine effects of CDR and reference clock jitter
- May lose some jitter amplification
- Fangyi: The word "incorporate" may be better than "combine"
- Radek: Does it currently say they are combined?
- Vladimir: We should say all TX jitter inputs may affect ISI
- Walter: The EDA tool may use any method to combine the jitters
- Back to slide 3 of "Components of an IBIS-AMI Simulation"
- Walter: RX GetWave has the CDR logic
- It is affected by:
- The reference clock that drives CDR
- Arpad: Are we trying to define what the EDA tool does for CDR?
- Walter: No, the DLL does the whole job
- The issue is when you have a forwarded clock
- The clock channel may be of different length
- Clock ticks could be from a PLL, analyzed at system level
- Arpad: We have no way to send ref clock to DLL
- Walter: Clock_times can be an input
- Kumar: PCIe has a forwarded clock option
- It is at a much lower data rate, a different beast
- Walter: Scott had requested this
- Not sure who would write a model to use this
- Todd: Normally a ref clock is multiplied up
- Is this ref at PCB level or for CDR?
- Walter: It has to include the effects of everything else
- Kumar: It has to all be in the Rx model
- Walter: The slow clocks have 32 phases
AR: Arpad post BIRD 137
Meeting ended.
-------------
Next meeting: 16 Aug 2011 12:00pm PT
Next agenda:
1) Task list item discussions
-------------
IBIS Interconnect SPICE Wish List:
1) Simulator directives
Other related posts:
- » [ibis-macro] Minutes for August ibis-atm meetings - Mike LaBonte
