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BIRD ID#:        93
ISSUE TITLE:     Model and Signal Name Limit Extension
REQUESTER:       Michael Mirmak, Intel Corp.
DATE SUBMITTED:  November 5, 2004
DATE ACCEPTED BY IBIS OPEN FORUM:  PENDING

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STATEMENT OF THE ISSUE:

Some internal design model and signal names may exceed the current 20 
character limit on the model_name and signal_name fields of [Model], 
particularly when the names are automatically generated.  These must be 
truncated before their inclusion in an IBIS file.

IBIS 4.1 extends maximum line lengths from 80 to 120 characters.  With this
change, model and signal names may safely be extended as well. This BIRD 
establishes a new limit of 40 characters on model and signal names.

Note that the proposed change does not alter the five character maximum 
length of pin designators.  Consequently, while [Series Pin Mapping] and 
[Model Selector] would be affected by this change, [Diff Pin] and 
[Pin Mapping] would not.

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STATEMENT OF THE RESOLVED SPECIFICATIONS:

Changes are noted in the relevant sections below by |* lines:

In section 5, under [Pin], replace:

|               Column length limits are:
|                   [Pin]         5 characters max
|                   model_name   20 characters max
|                   signal_name  20 characters max
|                   R_pin         9 characters max
|                   L_pin         9 characters max
|                   C_pin         9 characters max

with:
|               Column length limits are:
|                   [Pin]         5 characters max
|*                   model_name   40 characters max
|*                   signal_name  40 characters max
|                   R_pin         9 characters max
|                   L_pin         9 characters max
|                   C_pin         9 characters max

Under [Series Pin Mapping], replace:
|               The column length limits are:
|                   [Series Pin Mapping]       5 characters max
|                   pin_2                      5 characters max
|                   model_name                20 characters max
|                   function_table_group      20 characters max

with:
|               The column length limits are:
|                   [Series Pin Mapping]       5 characters max
|                   pin_2                      5 characters max
|*                   model_name                40 characters max
|                   function_table_group      20 characters max

Under [Model Selector], replace:
| Usage Rules: A programmable buffer must have an individual [Model] section
| for each one of its modes used in the .ibs file. The names of
| these [Model]s must be unique and can be listed under the
| [Model Selector] keyword and/or pin list. The name of the
| [Model Selector] keyword must match the corresponding model
| name listed under the [Pin] or [Series Pin Mapping] keyword
| and must not contain more than 20 characters. A .ibs file
| must contain enough [Model Selector] keywords to cover all of
| the model selector names specified under the [Pin] and [Series
| Pin Mapping] keywords.
|
| The section under the [Model Selector] keyword must have two
| fields. The two fields must be separated by at least one
| white space. The first field lists the [Model] name (up to 20
| characters long). The second field contains a short
| description of the [Model] shown in the first field. The
| contents and format of this description is not standardized,
| however it shall be limited in length so that none of the
| descriptions exceed the 120-character length of the line that
| it started on. The purpose of the descriptions is to aid the
| user of the EDA tool in making intelligent buffer mode
| selections and it can be used by the EDA tool in a user
| interface dialog box as the basis of an interactive buffer
| selection mechanism.

with
| Usage Rules: A programmable buffer must have an individual [Model] section
| for each one of its modes used in the .ibs file. The names of
| these [Model]s must be unique and can be listed under the
| [Model Selector] keyword and/or pin list. The name of the
| [Model Selector] keyword must match the corresponding model
| name listed under the [Pin] or [Series Pin Mapping] keyword
|* and must not contain more than 40 characters. A .ibs file
| must contain enough [Model Selector] keywords to cover all of
| the model selector names specified under the [Pin] and [Series
| Pin Mapping] keywords.
|
| The section under the [Model Selector] keyword must have two
| fields. The two fields must be separated by at least one
|* white space. The first field lists the [Model] name (up to 40
| characters long). The second field contains a short
| description of the [Model] shown in the first field. The
| contents and format of this description is not standardized,
| however it shall be limited in length so that none of the
| descriptions exceed the 120-character length of the line that
| it started on. The purpose of the descriptions is to aid the
| user of the EDA tool in making intelligent buffer mode
| selections and it can be used by the EDA tool in a user
| interface dialog box as the basis of an interactive buffer
| selection mechanism.

In Section 6, under [Model], replace:
| Usage Rules: Each model type must begin with the keyword [Model]. The
| model name must match the one that is listed under a [Pin],
| [Model Selector] or [Series Pin Mapping] keyword and must
| not contain more than 20 characters. A .ibs file must
| contain enough [Model] keywords to cover all of the model
| names specified under the [Pin], [Model Selector] and [Series
| Pin Mapping] keywords, except for those model names that use
| reserved words (POWER, GND and NC).

with:
| Usage Rules: Each model type must begin with the keyword [Model]. The
| model name must match the one that is listed under a [Pin],
| [Model Selector] or [Series Pin Mapping] keyword and must
|* not contain more than 40 characters. A .ibs file must
| contain enough [Model] keywords to cover all of the model
| names specified under the [Pin], [Model Selector] and [Series
| Pin Mapping] keywords, except for those model names that use
| reserved words (POWER, GND and NC).

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ANY OTHER BACKGROUND INFORMATION:

This issue has been separately raised by representatives of both EDA tool 
and semiconductor vendor companies.

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