Subject: IBISCHK3 BUG34

From: Bob Ross <[email-masked]>
Date: Thu, 13 Apr 2000 13:58:49 -0700

To All:

Discussion on BUG34 on ibischk3 is planned for the April 14, 2000
IBIS Meeting.  It is given below for reference.

Bob Ross
Mentor Graphics

******************************************************************************
********************* IBIS GOLDEN PARSER BUG REPORT FORM *********************
******************************************************************************

INSTRUCTIONS

To report a bug in the IBIS golden parser.  Please fill out the top part
of the following form and send the complete form to [email-masked].

A list of reported bugs will be maintained on vhdl.org.

******************************************************************************

PARSER VERSION NUMBER:
    Found in IBISCHK3 V3.2.1 built for DOS.  Confirmed in IBIS_CHK2 V2.1.17
    for DOS.

PLATFORM (SPARC, HP700, PC, etc.):
    PC

OS AND VERSION:
    Windows NT Server 4.0 (Build 1381: Service Pack 4)

REPORTED BY:
    Matthew Flora
    HyperLynx
    (425) 869-2320
    [email-masked]

DATE:
    12 Jan 1999
    27 Oct 1999 - Amended

DESCRIPTION OF BUG:
    The parser does not report an error if an output buffer has no V/I tables
    (and therefore is not an output).

    Perhaps the parser should test for the presence of certain V/I tables for
    other Model_types as well.

  AMENDMENT:
    After an IBIS Open Forum Teleconference discussion, it was decided that a
    warning should be given rather than an error.  Furthermore, the absence of
    clamp tables would not be reported.

    The wording I propose is lengthy, but it meets the need for an
    understandable description of the problem and a remedy.

    The warning given to the user should be dependant upon the Model_type of
    the buffer:

    Input, Input_ECL, Terminator, Series, Series_switch:
        No warning given.

    Output, Output_ECL, I/O, I/O_ECL, 3-state, and 3-state_ECL; [Pullup] table
    missing:
        "WARNING - Model 'XXX' does not contain a description of the buffer's
                   DC drive characteristics for the buffer's high state (no
                   [Pullup] table).  The model is not declared to be an open
                   drain buffer.  Perhaps it should be.  Alternatively, a
                   [Pullup] table containing all zero currents could be
                   added."

    Output, Output_ECL, I/O, I/O_ECL, 3-state, and 3-state_ECL; [Pulldown]
    table missing:
        "WARNING - Model 'XXX' does not contain a description of the buffer's
                   DC drive characteristics for the buffer's low state (no
                   [Pulldown] table).  The model is not declared to be an open
                   source buffer.  Perhaps it should be.  Alternatively, a
                   [Pulldown] table containing all zero currents could be
                   added."

    Output, Output_ECL, I/O, I/O_ECL, 3-state, and 3-state_ECL; Both [Pullup]
    and [Pulldown] tables missing:
        "WARNING - Model 'XXX' does not contain a description of the buffer's
                   DC drive characteristics for the buffer's high and low
                   state (no [Pullup] nor [Pulldown] table).  Therefore, the
                   model is of little use as an output.  If this is not a
                   mistake, consider adding [Pullup] and [Pulldown] tables
                   containing all zero currents."

    Open_drain, Open_sink, I/O_open_drain, and I/O_open_sink; [Pulldown] table
    missing:
        "WARNING - Model 'XXX' does not contain a description of the buffer's
                   DC drive characteristics for the buffer's low state (no
                   [Pulldown] table).  Therefore, the model is of little use
                   as an output.  If this is not a mistake, consider adding a
                   [Pulldown] table containing all zero currents."

    Open_source and I/O_open_source; [Pullup] table missing:
        "WARNING - Model 'XXX' does not contain a description of the buffer's
                   DC drive characteristics for the buffer's high state (no
                   [Pullup] table).  Therefore, the model is of little use
                   as an output.  If this is not a mistake, consider adding a
                   [Pullup] table containing all zero currents."

INSERT IBIS FILE DEMONSTRATING THE BUG:
    [IBIS Ver]        3.1 | or 2.1 or 1.1
    [File Name]       notables.ibs
    [File Rev]        0.1
    |
    |***************************************************************
    |
    [Component]      TEST
    [Manufacturer]   Test File
    [Package]
    | variable      typ             min             max
    R_pkg           0.0m            NA              NA
    L_pkg           0.0nH           NA              NA
    C_pkg           0.0pF           NA              NA
    |
    |***************************************************************
    |
    [Pin]           signal_name     model_name
    1               One_Pin         NC
    |
    |
    |***************************************************************
    |
    [Model]     no_tables
    Model_type  Output

    |                         typ          min          max
    C_comp                    2.6000pF     NA           NA
    [Voltage Range]           3.3000V      NA           NA

    [Ramp]
    |          typ                     min                     max
    dV/dt_r    1/1ns                   NA                      NA
    dV/dt_f    1/1ns                   NA                      NA

    [End]

******************************************************************************
******************** BELOW FOR ADMINISTRATION AND TRACKING *******************
******************************************************************************

BUG NUMBER:  34

SEVERITY: [FATAL, SEVERE, MODERATE, ANNOYING, ENHANCEMENT]   ANNOYING

PRIORITY: [HIGH, MEDIUM, LOW]                                LOW

STATUS: [OPEN, CLOSED, WILL NOT FIX, NOT A BUG]              OPEN

FIXED VERSION:

FIXED DATE:

NOTES ON BUG FIX: At the January 15, 1999 IBIS Meeting, we deferred fixing
                  BUG34 since we needed more time to decide how to fix it.
                  BUG34 proposals for Warning messages were issued by
                  Matthew Flora October 29, 1999 per an action item.

******************************************************************************
******************************************************************************