Subject: Bird 47

From: Stephen Peters <[email-masked]>
Date: Thu, 05 Mar 1998 16:06:26 -0800

Hello All:

    The parser developer raised the following issue with the [Pin List]
keyword syntax ([Pin List] is found in the Electrical Board Description
section of IBIS ver3.0).  Because it is a syntax issue, a bird is required
to fix it.  After confering with Bob Ross, here is the proposed change.

          Regards,
          Stephen Peters
          Intel Corp.

                 Buffer Issue Resolution Document  (BIRD)

BIRD ID#:    Bird 47
ISSUE TITLE: Remove pin name as a sub-param of the [Pin List] keyword 
REQUESTOR:   Stephen Peters  Intel Corp.

DATE SUBMITTED:  March 5, 1998
DATE ACCEPTED BY IBIS OPEN FORUM:

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STATEMENT OF THE ISSUE: The current [Pin List] keyword in the Electrical
Board Description of the specification list two subprameters -- pin_name
and signal_name.  However, this syntax/format is not consistent with the
[Pin] or [Pin Number] keywords in the rest of the specification.
Specificaly, the 'pin name' should be what the keyword is listing, not
a sub-param to the keyword.  Therefore, 'pin_name' should be removed as
a subparameter from the [Pin List] keyword, and the example changed.

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STATEMENT OF THE RESOLVED SPECIFICATIONS:  Replace the current [Pin List] 
keyword description and example in the Electrical Board Description section
of the specification with the following.

|=============================================================================
|     Keyword:  [Pin List]
|    Required:  Yes
| Description:  Tells the parser the pin names of the user accessible pins.
|               It also informs the parser which pins are connected to power
|               and ground. 
|  Sub-Params:  signal_name
| Usage Rules:  Following the [Pin List] keyword are two columns.  The first
|               column lists the pin name while the second lists the data book 
|               name of the signal connected to that pin. There must be as 
|               many pin_name/signal_name rows as there are pins given by the 
|               preceding [Number Of Pins] keyword.  Pin names must be the 
|               alphanumeric external pin names of the part.  The pin names
|               cannot exceed eight characters in length.  Any pin associated
|               with a signal name that begins with "GND" or "POWER" will be
|               interpreted as connecting to the boards ground or power plane.
|               In addition, NC is a legal signal name and indicates that the
|               Pin is a 'no connect'.  As per the IBIS standard "GND",
|               "POWER" and "NC" are case insensitive.
|-----------------------------------------------------------------------------
|  A SIMM Board Example
|
[Pin List]  signal_name
 A1          GND
 A2          data1
 A3          data2
 A4          POWER5    | this pin connects to 5v
 A5          NC        | a no connect pin
| .
| .
 A22         POWER3.3  | this pin connects to 3.3v
 B1          casa
| .
| .
|etc.
|
|=============================================================================

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ANALYSIS PATH/DATA THAT LED TO SPECIFICATION:  This problem was found while
the parser for IBIS ver3.0 was being developed.  Bob Ross (unofficial
keeper of the ibis syntax and syle) concures with the change.

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ANY OTHER BACKGROUND INFORMATION:

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