Draft Minutes of SPI-2/SPI-3 WG Meeting -- Mar 16, 1998

John Lohmeyer lohmeyer at ix.netcom.com
Tue Mar 24 18:05:30 PST 1998


* From the T10 (formerly SCSI) Reflector (t10 at symbios.com), posted by:
* John Lohmeyer <lohmeyer at ix.netcom.com>
*
Accredited Standards Committee*
National Committee for Information Technology Standards (NCITS)

                                                      Doc. No.: T10/98-125r0
                                                          Date: March 24, 1998
                                                      Reply to: John Lohmeyer

To:             T10 Membership
From:           Ralph Weber / John Lohmeyer
Subject:        SPI-2 / SPI-3 Working Group Meeting -- March 16, 1998
                San Diego, CA

Agenda

1.  Opening Remarks
2.  Approval of Agenda
3.  Attendance and Membership
4.  SPI-3 Topics
4.1    Staged Contact Resistance (98-xxx) [Herrman]
4.2    Load Compensation (97-281) [Novak]
4.3    Universal Backplane Annex (98-101) [Wallace]
4.4    Bias Reduction Proposal (98-132) [Bridgewater]
4.5    Dual Clocking Proposal (97-208) [Bastiani]
4.6    Test results on dual edge signals (98-113r0) [Bastiani]
4.7    Testing results on hot plugging perturbations (98-129r0) [Gintz]
4.8    Packetized Protocol review (97-230r5) [Penokie/Williams]
4.9    QAS review (97-199r7 and 98-133r0) [Moore]
4.10   CRC proposal for SPI-3 [Penokie]
5.  SPI-2 Topics
5.1    0.5 pF balance capacitance for LVD SCSI (98-131) [Aloisi/Kapraun]
5.2    LVD ESD Concerns [Kapraun]
5.3    Removal of overlapped commands (duplicate queue tags) checking in SPI-2
       [Williams]
5.4    Terminator Power voltage level [Wallace]
5.5    SPI-2 Proposed letter ballot response review (98-108r1) [Penokie]
5.5.1     EIA - 485 versus ISO/IEC 8482 versus SPI-2 [Milligan]
5.5.2     SPI-2 Differential Cable Common Mode Voltage Requirements [Milligan]
6.  Meeting Schedule
7.  Adjournment

Results of Meeting

1.      Opening Remarks

John Lohmeyer, the T10 Chair, called the meeting to order at 9:00 a.m., Monday
March 16, 1998.  He thanked Skip Jones and QLogic for arranging and hosting
the meeting.

As is customary, the people attending introduced themselves and a copy of the
attendance list was circulated.  John noted that standards cannot contain
known patented material unless the patent holder agrees to comply with the
ANSI patent policy.

2.      Approval of Agenda

The draft agenda was approved with the no additions or changes.  No agenda
items were added during the course of the meeting.

3.      Attendance and Membership

Attendance at working group meetings does not count toward minimum attendance
requirements for T10 membership.  Working group meetings are open to any
person or organization directly and materially affected by T10's scope of
work.  The following people attended the meeting:

         Name          S        Organization         Electronic Mail Address
---------------------- -- ------------------------- -------------------------
Mr. Lawrence J. Lamers P  Adaptec, Inc.             ljlamers at ix.netcom.com
Mr. Vincent Bastiani   A# Adaptec, Inc.             bastiani at corp.adaptec.com
Mr. Mark Delsman       A# Adaptec, Inc.             mdelsman at corp.adaptec.com
Mr. Tak Asami          V  Adaptec, Inc.             asami at itc.adaptec.com
Mr. Wally Bridgewater  V  Adaptec, Inc.             wally at eng.adaptec.com
Mr. Bill Gintz         V  Adaptec, Inc.             bgintz at corp.adaptec.com

Mr. Richard Moore      V  Adaptec, Inc.             richard_moore at corp.
                                                    adaptec.com
Mr. Tom Schneider      V  Adaptec, Inc.             schneid at itc.adaptec.com
Mr. Charles Brill      P  AMP, Inc.                 cebrill at amp.com
Mr. Scott Lindstrom    O  AMP, Inc.                 slindstr at amp.com
Mr. Hank Herrmann      V  AMP, Inc.                 Hank.Herrmann at amp.com
Mr. Bill Mable         A  Amphenol Interconnect     bmable at spectra.net
Mr. Ron Roberts        A  Apple Computer            rkroberts at aol.com
Mr. Douglas Wagner     P  Berg Electronics          wagnerdl at bergelect.com
Mr. Bob Gannon         O  C&M Corp.                 rgannon at cm-corp.com
Mr. Edward Haske       O  CMD Technology            haske at cmd.com
Mr. Robert C. Elliott  O  Compaq Computer Corp.     relliott at compaq.com
Mr. Bill Galloway      O  Compaq Computer Corp.     Bill.Galloway at compaq.com
Mr. Charles Tashbook   P  Dallas Semiconductor      charles.tashbook at dalsemi.
                                                    com
Mr. Greg McSorley      P  Data General / Clariion   greg_mcsorley at dgc.ceo.dg.
                                                    com
Dr. William Ham        A# Digital Equipment Corp.   bill.ham at digital.com
Mr. George Penokie     P  IBM Corp.                 gop at us.ibm.com
Mr. Dan Colegrove      A# IBM Corp.                 colegrov at us.ibm.com
Mr. Dennis Moore       P  KnowledgeTek, Inc.        dmoore at ix.netcom.com
Mr. Dean Wallace       P  Linfinity Micro           75671.3443 at compuserve.com
Mr. Alan Littlewood    P  LSI Logic Corp.           alanl at lsil.com
Mr. Jay Neer           A  Molex Inc.                jneer at molex.com
Mr. Chris Millsaps     V  Mylex Corp.               chrism at mylex.com
Mr. Skip Jones         P  QLogic Corp.              sk_jones at qlc.com
Mr. Ting Li Chan       A  QLogic Corp.              t_chan at qlc.com
Mr. Chuck Micalizzi    V  QLogic Corp.              c_micalizzi at qlc.com
Mr. Patrick McGarrah   P  Quantum Corp.             pat.mcgarrah at quantum.com
Mr. James McGrath      A# Quantum Corp.             JMCGRATH at QNTM.COM
Mr. Bruce Leshay       V  Quantum Corp.             bleshay at tdh.qntm.com
Mr. Richard Uber       V  Quantum Corp.             duber at tdh.qntm.com
Mr. Gene Milligan      P  Seagate Technology        Gene_Milligan at notes.
                                                    seagate.com
Mr. Gerald Houlder     A  Seagate Technology        Gerry_Houlder at notes.
                                                    seagate.com
Mr. John M. Wright     V  Seagate Technology        John_M_Wright at notes.
                                                    seagate.com
Mr. Dave Guss          P  Silicon Systems, Inc.     dave.guss at tus.ssi1.com
Mr. Vit Novak          A  Sun Microsystems, Inc.    vit.novak at sun.com
Mr. John Lohmeyer      P  Symbios, Inc.             lohmeyer at ix.netcom.com
Mr. Ralph O. Weber     A  Symbios, Inc.             roweber at acm.org
Mr. Graeme Weston-     A# Symbios, Inc.             gwl at symbios.com
Lewis
Mr. Frank Gasparik     V  Symbios, Inc.             frank.gasparik at symbios.
                                                    com

Mr. Steve Stefek       V  Symbios, Inc.             steve.stefek at symbios.com
Mr. Paul D. Aloisi     P  Unitrode Corporation      aloisi at unitrode.com
Mr. Jeffrey L.         P  Western Digital           Jeffrey.L.Williams at wdc.
Williams                  Corporation               com
Mr. Gregory Kapraun    A  Western Digital           Gregory.D.Kapraun at wdc.com
                          Corporation

48 People Present

Status Key:  P    -  Principal
             A,A# -  Alternate
             O    -  Observer
             L    -  Liaison
             V    -  Visitor
4.      SPI-3 Topics

4.1     Staged Contact Resistance (98-xxx) [Herrman]

Hank Herrman noted that AMP had applied for a patent related to the material
to be presented.  He expected that AMP would comply with the ANSI patent
policy should the material be included in SPI-3.

Hank presented an analysis of signal behavior on connector mating.  The
analysis included a model for initial contact (touching of conductors) and
several other properties of connector mating behavior.  Hank showed signal
traces based on the model for transients caused by contact mating.  He then
described a mechanical change to the contact surfaces that would introduce
several levels of resistance in the contacts with the effect that the
transients are reduced.  The group expressed interest in the connector design
and the hope that such a design would make hot-plugging more reliable for
parallel SCSI busses.  It was felt that more discussions would be required
before a specific proposal could be made.

4.2     Load Compensation (97-281) [Novak]

Vit Novak followed-up on his presentation from the previous meeting showing
how compensating circuitry can be placed on a backplane to improve the signal
quality seen by devices.  He noted that many components are required to
support a typical backplane and suggested that the components might be applied
to sets of around three drives with equal effectiveness, thus reducing the
cost.

Bill Ham asked the group to think about where the information could be placed.
George Penokie suggested an informative annex in SPI-3.  Vit indicated that
the ideas presented are not needed for LVD SCSI and would be useful only for
higher transfer rates, thus confirming that SPI-3 would be more appropriate
than SPI-2.

4.3     Universal Backplane Annex (98-101) [Wallace]

Dean Wallace reported that a revised draft of the document will be in the
mailing and requested that further discussion be deferred to the May agenda.

4.4     Bias Reduction Proposal (98-132) [Bridgewater]

Wally started his presentation by proposing that the bias be removed for
Fast-80, having the host or the target supply the bias, and be able to turn it
off during data phase.  It developed that the proposal depends on the
initiator knowing in advance when the target is switching to a data phase.
Such knowledge would be required to change the bias quickly.  The group
discussed how to minimize the time required to switch the bias when changing
in to or out of data phase, including the time needed to let the bus settle
(or adjust to the bias change).


It was noted that the proposal allows compensation for some of the fixed
tolerances currently present in the SPI-2 electrical signaling requirements.
This led to a discussion of compensating for other tolerances by adding a
signal integrity testing procedure to the protocol.  Both ideas met with
general agreement, but issues around effects on higher protocol levels were
raised.  Wally agreed to bring a more detail proposal to the next meeting.

Wally then repeated his request that the open circuit LVD driver voltage be
reduced to 2.5 volts.  Noting that the request depends on a long succession of
future performance improvements in parallel SCSI, some present suggested that
no change may be necessary.

4.5     Dual Clocking Proposal (97-208) [Bastiani]

Vince Bastiani reported that dual-edge signal testing is still in progress and
requested that further discussion be deferred to the May agenda.

4.6     Test results on dual edge signals (98-113r0) [Bastiani]

Vince Bastiani reported that testing is still in progress and requested that
further discussion be deferred to the May agenda.

4.7     Testing results on hot plugging perturbations (98-129r0) [Gintz]

Bill Gintz presented some laboratory results on hot plugging.  His
experimental setup included a scope that triggered on between 50 and 100
millivolt swings on an ACK line in nanosecond time frames.  The first scope
triggered a second scope scanning at a hundred microseconds per division.
This allowed for examination of both the high-speed and low-speed effects of
hot plugging.  Bill felt that some of his observed results were explained by
the theoretical calculations described by Hank Herrman (see 4.1).

Bill noted several glitches on all of the lines he sampled, as well as
concerns about transients caused by unplugging, an situation that he felt the
group was ignoring.

4.8     Packetized Protocol review (97-230r5) [Penokie/Williams]

George Penokie reviewed the packetized protocol proposal placed on the FTP
site in December.  The group commented on the proposal, noting several
specific technical and typographical errors.  It was agreed to remove
selection with ATN when information unit phases are enabled (unless the
proposal authors can provide a justification for its presence in the
standard).  George stated his plan to revise the document for another round of
review during the SCSI Working Group meeting.

4.9     QAS review (97-199r7 and 98-133r0) [Moore]

Richard Moore presented a overview (98-133r0) of latest revision of the Quick
Arbitrate and Select (QAS) proposal (97-199r7).  In the course of the
discussion, it became clear to two expander vendors that the current expanders
will not work with QAS.  Also, total bus length for many bus expander
implementations might be reduced by some of the timing specifications in QAS.
Still, those present felt that bus expanders can be built to support QAS.
Richard agreed to prepare a new revision of the QAS proposal for consideration
at the May meeting.  He expressed the belief that the next revision will not
be the last.


4.10    CRC proposal for SPI-3 [Penokie]

George Penokie asked that discussion of this proposal be deferred to the May
meeting.

5.      SPI-2 Topics

5.1     0.5 pF balance capacitance for LVD SCSI (98-131) [Aloisi/Kapraun]

Due to the late hour, discussion of this topic was moved to the SCSI Working
Group meeting.

5.2     LVD ESD Concerns [Kapraun]

Due to the late hour, discussion of this topic was moved to the SCSI Working
Group meeting.

5.3     Removal of overlapped commands (duplicate queue tags) checking in
SPI-2 [Williams]

Due to the late hour, discussion of this topic was moved to the SCSI Working
Group meeting.

5.4     Terminator Power voltage level [Wallace]

Due to the late hour, discussion of this topic was moved to the SCSI Working
Group meeting.

5.5     SPI-2 Proposed letter ballot response review (98-108r1) [Penokie]

Due to the late hour, discussion of this topic was moved to the SCSI Working
Group meeting.

5.5.1   EIA - 485 versus ISO/IEC 8482 versus SPI-2 [Milligan]

Due to the late hour, discussion of this topic was moved to the SCSI Working
Group meeting.

5.5.2   SPI-2 Differential Cable Common Mode Voltage Requirements [Milligan]

Due to the late hour, discussion of this topic was moved to the SCSI Working
Group meeting.

6.      Meeting Schedule

The next meeting of SPI-3 Working Group will be May 4, 1998 in Colorado
Springs, CO at the Doubletree World Arena Hotel (719-576-8900), hosted by
Symbios, Inc.  The meeting will begin at 9:00 a.m. on Monday.

7.      Adjournment

The meeting was adjourned at 7:00 p.m. on Monday March 16, 1998.



--
John Lohmeyer                  Email: lohmeyer at ix.netcom.com
Symbios, Inc.                  Voice: +1-719-533-7560
4420 ArrowsWest Dr.              Fax: +1-719-533-7036
Colo Spgs, CO 80907              BBS: +1-719-533-7950

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