Arpad,
So if a model maker outputs a Model Specific parameter Framis, and the
documentation with the model says that the buffer works better with Framis
being as small as possible, and we give our customers the ability to
optimize the system to minimize the value of Framis, “Is this not a good
thing”.
Walter
From: ibis-macro-bounce@xxxxxxxxxxxxx
[mailto:ibis-macro-bounce@xxxxxxxxxxxxx] On Behalf Of Muranyi, Arpad
Sent: Wednesday, July 29, 2015 5:49 PM
To: ibis-macro@xxxxxxxxxxxxx
Subject: [ibis-macro] Re: PAM4 Out parameters question from yesterday's
meeting.
Walter,
Forget about the specific wording for a moment and let us
focus on the logic of this situation.
The greatest advantages of IBIS modeling is portability and
interoperability. I have seen these words in numerous SiSoft
presentations, so I think we are in agreement there. This was
one of the main reasons the IBIS standard was invented and the
main reason it was successful for so many years, despite its
numerous and sometimes serious limitations.
Suppose a model maker creates a model with a Model_Specific
parameter which supposed to have a very unique purpose in that
model. Since this is a Model_Specific parameter, the specification
cannot describe its meaning, purpose, usage, etc…, so EDA vendors
cannot implement any support for that very unique purpose (unless
they are good friends with the model maker, or perhaps are the
same company).
Now how portable is this model?
Do you think the IBIS specification should endorse and encourage
this situation, essentially undermining its own fundamental purpose
of promoting and supporting portable and interoperable models?
Let’s answer these questions first, and once we have the answer we
can worry how that should be worded, if at all.
Thanks,
Arpad
=====================================================================
From: Walter Katz [mailto:wkatz@xxxxxxxxxx]
Sent: Wednesday, July 29, 2015 4:20 PM
To: Muranyi, Arpad; curtis.clark@xxxxxxxxx <mailto:curtis.clark@xxxxxxxxx> ;
ibis-macro@xxxxxxxxxxxxx <mailto:ibis-macro@xxxxxxxxxxxxx>
Subject: RE: PAM4 Out parameters question from yesterday's meeting.
Arpad,
To be specific, in
<http://www.vhdl.org/pub/ibis/macromodel_wip/archive/20110613/arpadmuranyi/Out-InOut%20BIRD%20draft%2010/Out_InOut_BIRD_10.pdf>
http://www.vhdl.org/pub/ibis/macromodel_wip/archive/20110613/arpadmuranyi/Out-InOut%20BIRD%20draft%2010/Out_InOut_BIRD_10.pdf
| However, in order to be compliant with this specification, Model_Specific
| parameters of (Usage Out), (Usage InOut) or (Usage Info) must not be used
| in any way to influence the EDA platform in how it prepares the input data
| for the algorithmic models, and/or how it processes the data returned by
| the algorithmic models.
I think the intent is quite clear. The specification describes the inputs
and outputs of a DLL. The specification has some reference flows. So this is
an attempt to limit what an EDA tool can do with Model Specific Out
parameters. Or do I not understand the meaning of “must not be used in any
way”. And what does “compliant with this specification” mean. The .ibs file,
the .ami file and .dll have “compliant” rules, since when are we in the
business of “compliant” rules for EDA tools?
Walter
