[ibis-macro] Minutes from 4/13 ibis-atm meeting
- From: "Randy Wolff (rrwolff)" <rrwolff@xxxxxxxxxx>
- To: <ibis-macro@xxxxxxxxxxxxx>
- Date: Thu, 15 Apr 2010 14:59:49 -0600
Here are the minutes from the 4/13 IBIS-ATM meeting.
Randy
IBIS Macromodel Task Group
Meeting date: 13 April 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
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: Did we decide on a uniform list of tool/IC vendors supporting
AMI?
Arpad: tool vendors will do their own announcements.
Walter: Is there a place on IBIS website for those who support IBIS?
Michael: Model library is a comprehensive list.
Bob: Roster page also lets companies show how they support IBIS.
Walter: Thinks this is the appropriate place for that.
--------------------------
Call for patent disclosure:
- No one declared a patent.
-------------
Review of ARs:
- Arpad: send the two BIRD documents and updated spreadsheet to Mike L. to be
posted
- done
- 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 updated Task List spreadsheet
Arpad: Groups of items in the spreadsheet are parser developer questions, AMI
flow related, and ambiguities in the text.
Arpad: Under scale factors, what is 'clarify AMI is a control/initialization
syntax'?
- Bob: Just that AMI should not support scale factors.
Arpad: Under white space, is CRLF allowed in .ami files or parameter strings
extracted from it?
- Bob: In .ami file, anything is allowed by the parser.
- Michael M: The .ami section of the spec covers this maybe, but it isn't
clear if
it describes what is allowed in the parameter string for the DLL extracted
from it.
- Arpad: Parameter strings are a separate topic.
Arpad: Will take offline questions on lines 17 to 23.
2. Discuss AMI Flow BIRD
Arpad: Ken Willis, Ambrish, and Fangyi all sent emails to the reflector related
to the
Init_Returns_Filter boolean. They were in opposition to including this in the
current
Flow clarification.
Arpad showed a flow without this boolean. He found issues when both Tx_GetWave
and
Rx_GetWave exist.
- Ambrish: You can use the flow in the current spec.
- Arpad: Same issue with Tx_GetWave only.
Ambrish: Slide 6 is a special case. We won't expect an equalization in the Init
call and
GetWave at the same time.
- Arpad: The boolean is appropriate in this case. Either we don't support
this case at
all or we support the boolean.
- Ambrish: Might be another way of doing this that Kumar discussed. The tool
generates
a unit impulse response.
Arpad: Making any changes will take another month at least to approve. We need
to decide
today whether to make more changes or go with the flow decided last year.
- Fangyi: Before we were talking about a new spec. Now we are talking about a
cleanup only.
We can introduce this in a new version of the standard, but not in a
cleanup BIRD.
- Arpad: But is it worth our time to create two separate BIRDs on the flow?
- Ambrish: Adding this boolean makes the flow a lot more complex.
- Fangyi: Adding this boolean doesn't fix current models, that is why it is a
new feature.
Arpad: Change plan on voting on the BIRD and instead vote on whether we keep
the BIRD as
it is (Yes) or whether we create a separate cleanup BIRD (No).
Vote results:
Ambrish No
Arpad Yes
Bob Abstain
Danil Yes
Fangyi No
Ken No
Michael No
Randy Abstain
Todd Yes
Arpad: With a No vote, he will prepare a new flow for next week that satisfies
the
existing clarification flow as well as the new flow.
- Fangyi: All the analysis of different scenarios is still valid for the new
flow.
3. Clock_times BIRD discussion
Arpad: Showed a difference view between the old and new clock_times description
in
the specification.
- Scott: Main difference is redefinition of period to be the instantaneous
period.
One interpretation means the nominal UI of the bit stream, but physical
device
doesn't care about that. This is incorrect and can give the wrong results
when
we look at the sampled point and the clock from the CDR.
Scott: This BIRD defines what a clock_time is and what it means. It eliminates
anomalies found in current models. Clocks must be monotonic. A pair of
values
in the clock time array are used to derive the instantaneous sample point,
not
an average sample point.
- Fangyi: What if there is a missing clock tick? He remembers in current spec
that
there could be a missing tick.
- Scott: The tick is a physical sampling point in time.
- Vladimir: There is confusion between two things. Number of clock ticks
could be
different from number of samples. Once all GetWaves are combined, there
should
be no missing times.
- Scott: if a CDR failure occurs, goes out of lock, you get longer or shorter
intervals.
This is ok.
Scott: Clock times are the transition edge of the phase lock clock. Second
statement
says that sample is assumed to occur half a clock period after that. One can
make
it either nominal or the instantaneous clock time. If nominal, in a CDR
system,
if sending back the phase locked clock and if not a nominal period, EDA
platform
computes the wrong sample point.
- Fangyi: Model makers are concerned about where the clock is centered, not
where
it is sampled.
- Scott: The only important thing to the EDA platform is where the sample
point
is, but it isn't being returned.
- Walter: AMI modeling system is similar to IBM's HSSCDR. It outputs the
waveform and
where the location is being sampled. The clock ticks are meant to be
related to
1/2 the nominal UI period. The spec says "one half clock period" but should
be
one half bit time.
- Scott: will re-write the spec to indicate that clock times are calculated
based
on the internal sample point corrected by 1/2 the nominal UI.
Vladimir: How can we distinguish? What should EDA tool do if clock times will
appear after one million bit simulation.
- Arpad: The issue is if a tool can distinguish between getting no clock
times
and getting clock times after a very long wait. This affects memory
allocation.
- Fangyi: You can prepare the eye when no clock ticks return using uniform
clock
ticks. If you get real clock ticks, then use them and throw out the uniform
clock
ticks. You have to assume the clock ticks relate to time zero when they do
arrive.
AR: Arpad to create new flow diagram for the clarification BIRD.
AR: Scott to rewrite clock ticks BIRD
Next meeting: 20 Apr 2010 12:00pm PT
--------
IBIS Interconnect SPICE Wish List:
1) Simulator directives
Other related posts:
- » [ibis-macro] Minutes from 4/13 ibis-atm meeting - Randy Wolff (rrwolff)
