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BIRD ID#:        139
ISSUE TITLE:     Reserved_Parameters Order
REQUESTER:       Bob Ross, Teraspeed Consulting Group
DATE SUBMITTED:  June 21, 2011 
DATE REVISED:
DATE ACCEPTED BY IBIS OPEN FORUM:  

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STATEMENT OF THE ISSUE:

In general there are no order dependency rules in the .ami file.  The
(required) Reserved_Parameters section is not required to appear before the
Model_Specific section.  However, with approved BIRD126 (adding AMI_Version)
the Reserved_Parameters branch needs to appear first for IBIS Version 5.1
and above so that new features can be immediately identified and processed
according to the correct Specification version.


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STATEMENT OF THE RESOLVED SPECIFICATIONS:


On Page 143, change the paragraph


|               The ‘Reserved_Parameter’ section is required while the
|               ‘Model_Specific’ section is optional.  The sub-trees can be
|               in any order in the parameter file.  The ‘|’ character is the
|               comment character.  Any text after the ‘|’ character will be
|               ignored by the parser.
|

to

|               The ‘Reserved_Parameter’ section is required while the
|*              ‘Model_Specific’ section is optional.  For AMI_Version 5.1
|*              and above, the Reserved_Parameter sub-tree shall appear
|*              before the Model_Specific sub-tree.  The ‘|’ character is the
|               comment character.  Any text after the ‘|’ character will be
|               ignored by the parser.
|




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ANALYSIS PATH/DATA THAT LED TO SPECIFICATION

In all IBIS formats (.ibs, .pkg, .ebd, .icm) and Touchstone 2.0, the Version
information is required as the first keyword so that the remaining content
can be immediately parsed at the specified Version.  This is now very
desirable for .ami files with the approval of BIRD126 which already mandates
that AMI_Version appear first under the Reserved_Parameters sub-tree. 

The diagram organization on page 144 shows Reserved_Parameters first, and
this organization appears already to be common practice.

With the new requirement that Reserved_Parameters be positioned first,
the AMI_Version can be determined, and .ami file legal set of parameters and
structures can be parsed during the first pass.  Otherwise a separate pass
might be needed.


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ANY OTHER BACKGROUND INFORMATION:

The word "sub-tree" is not modified in this BIRD.  However the word
"branch" appears in BIRD126.  The final terminology might be decided later
for overall IBIS-AMI terminology consistency.

This BIRD draft was discussed during the June 21, 2011 ATM Task Group
meeting and there were no objections or issues concerning this BIRD.


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