Minutes of Weekly Meeting, 2010-03-22

Meeting called to order at 10:35 AM EST

1. Roll Call

Carl Walker
Adam Ley
Brad Van Treuren
Brian Erickson
Eric Cormack
Heiko Ehrenberg
Michele Portolan
Ian McIntosh

Tim Pender
Peter Horwood

2. Review and approve previous minutes:

03/15/2010 minutes:

  • Draft circulated on 15th March:
  • No corrections noted.
  • Eric moved to approve, seconded by Brian; no objections or abstentions.

3. Review old action items

  • Adam proposed we cover the following at the next meeting:
    • Establish consensus on goals and constraints
    • What are we trying to achieve?
    • What restrictions are we faced with?
  • Establish whether TRST needs to be addressed as requirements in the ATCA specification if it is not going to be managed globally (All)
  • Adam review ATCA standard document for FRU's states
  • All to consider what data items are missing from Data Elements diagram
  • All: do we feel SJTAG is requiring a new test language to obtain the information needed for diagnostics or is STAPL/SVF sufficient? see also Gunnar's presentation, in particular the new information he'd be looking for in a test language
  • Ian/Brad: Draft "straw man" Volume 4 for review - Ongoing
  • All: Review "Role of Languages" in White Paper Volume 4 - Ongoing
  • All: Review 'straw man' virtual systems and notes on forums:
    http://forums.sjtag.org/viewtopic.php?f=29&t=109. - Ongoing
  • All: Add to, or comment on, the bullet point list of architecture drivers. - Ongoing.
  • All: Provide forum comment on the graphics used during the meeting; suggest "building blocks" that may be used in future:
    http://forums.sjtag.org/viewtopic.php?f=29&p=257#p257 - Ongoing.
  • Heiko: create forum entries for what we have so far for further discussions / details; send out an email with links to these new forum topics. - COMPLETE
  • ALL: review / comment in preparation for upcoming meetings. - Ongoing
  • Ian: Draft a generic system diagram for discussion next week. - COMPLETE.
  • [Ian] We have a few actions requiring review or comment on things that have been around for a while. We should maybe take time during a meeting soon to see if we can clear some of these off.

4. Discussion Topics

  1. White Paper Volume 3 Review - Discussion of sample system diagram
    • [Ian] I mailed out a diagram, along with some description.
    • {PDF of diagram shared}
    • [Ian] There were some comments from Brad suggesting that there may be some even simpler cases that we should consider first, and Michele proposed that there could be an extension of this into the SoC area.
    • [Brad] We're describing a hierarchy of elements. We're showing multiple chains and simple though it is, it's maybe still too much for a novice. I think we need to show a single chain to do a task, that's the board level, and then we extend that through the backplane to be driven by an external controller. I did think about bringing in a System Controller at this point but that's probably too much. So then we can go to having more than one chain on each PCB. And then we have the issue of daughter boards, so we have a chain that passes out of the board to the daughter board.
    • [Ian] Were you envisaging the daughter board chain being taken to the board boundary?
    • [Brad] It's different boundary. Looking at our primitives, we have the Scan Cell with Scan In, Scan Out, Parallel In and Parallel Out and these are defined in the BSDL, but what we're really describing is ports used for control. The next slice above that is the registers and really these are ports again. The TAP controller brings in the dynamic element of the selection logic.
    • [Brad] Start with a description of the basics here and show that we're expanding on 1149.1.
    • [Brad] I'm still thinking this through: Ports are being defined that will mate together. I've been trying to find a way that we can represent this. It's in the JTAG Connectivity Infrastructure that the ports will be defined.
    • [Ian] I agree, what I wasn't wanting to do there was to suggest the existence of gateways or switches; just 'some undefined medium'.
    • [Brad] Even as this is, it presents a lot of information.
    • [Ian] I was trying to start off with a simple example that most people could relate to at the board level then gradually introduce features.
    • [Brad] I was thinking of a black box perspective - describe what it does not how it does it. We could define a black box that just has ports. That means that diagrams get simpler as our ideas get more complex. We do this all the time with object oriented software; we should be able to do it with hardware.
    • [Ian] I was aiming at a simple representation for the novice hardware designer.
    • [Brad] The black box is really a white box that's been previously defined.
    • [Brad] This also lets us expand into the SoC field, but we probably do that after we've looked at the board level.
    • [Michele] Almost everything we see on the diagram can easily be applied to SoCs.
    • [Brad] Again it's a matter of defining the ports and the hierarchical flow. Adam - how does this relate to anything in HSDL? I think in the early days you were also looking at ports.
    • [Adam] I'm not sure that I have anything significant to add. HSDL does deal with Scan ports; I don't know if that is useful. Parallel didn't really get addressed in the original HSDL, but HSDL.7 that goes along with 1149.7 does bring it up through the hierarchy.
    • [Ian] In my emails with Brad, I said that I wasn't sure if this diagram was part of the White Paper or part of some set of tutorial slides. Either way it's form of education, although Brad commented that he usually found that one-to-one sessions were needed to get the concepts across.
    • [Brad] Yeah, that's the challenge with any textual or graphical method: It's always raised more questions than it resolved.
    • [Ian] Has anyone else got an opinion? Are we heading in the right direction by looking at ports?
    • [Heiko] I haven't really had a chance to look at this until this morning.
    • [Eric] Ports are good way to describe it. Ports are supported by languages and when we get into diagnostics it could help us by identifying which ports are failing.
    • [Brad] It'll certainly let us know what types of ports will be needed.
    • [Eric] That would also work on the SoC and 3D stacked dies.
    • [Brad] It should let us look at what languages are achieving that description. Some might be overkill.
    • [Eric] There's also the 'comfort factor' - a language might have overkill, but as long as people are used to using it, it can be useful.
    • [Brad] True. It will also help us to understand how we can extend existing standards.
    • [Ian] OK, I think we've gone as far as we can today on this. I think I need to try to expand this diagram with some of the ideas we've talked about. As Brad and I both look to be pretty busy, I don't think we'll manage to develop much further in the next few days though.
    • [Ian] I also think I need to make the diagram available on the website for discussion, rather than just sitting in people's mailboxes. {ACTION}
    • [Brad] Ian, the comments in my email also apply to the diagrams in the original White Paper; they just have too many things going on.
    • [Ian] Yes, I agree. I looked back at the original diagrams before I started on this, and unless you already know something of what you're looking for then they can be more confusing than helpful.

5. Schedule next meeting

Schedule for March 2010:
Monday March 29, 2010, 10:30 AM EDT

Schedule for April 2010:
Monday April 12, 2010, 10:30 AM EDT
Monday April 19, 2010, 10:30 AM EDT
Monday April 26, 2010, 10:30 AM EDT

Brad, Carl and Peter will miss March 29th.
Eric will likely miss all meetings in April.

As April 5th is the Easter Monday Holiday in the UK and attendance was likely to be low, it was agreed that there will be no meeting on April 5th.

6. Any other business

  • [Ian] I realised during the course of last week that the deadline for ITC paper submissions had passed. I don't really think we had anything that would justify a full paper anyway, but I do hope that we're doing now maybe with some data pulled from the survey will warrant a poster session.
  • [Ian] I think we need to get back to having a presence at ITC to keep us in the public mind.
  • [Eric] Are people likely to find it easier to get to ITC this year?
  • [Ian] I hopeful that travel restrictions won't be as severe. Maybe other industry sectors will be still face difficulty though.

7. Review new action items

  • Ian: Make update of diagram discussed today available through the website.

8. Adjourn

Eric moved to adjourn at 11:27 AM EST, seconded by Brian.

Respectfully submitted,
Ian McIntosh