Minutes of P2654 Working Group Meeting No.61, 2020-04-06

Meeting called to order: 11:05 AM EDT

The slide references relate to the pack used during this meeting, located here: http://files.sjtag.org/P2654WG/P2654_Meeting_61.pdf

1. Roll Call

Ian McIntosh (Leonardo)
Eric Cormack (DFT Solutions)
Terry Duepner (National Instruments)
Heiko Ehrenberg (GOEPEL Electronics)
Brian Erickson (JTAG Technologies)
Peter Horwood (Digital Development Consultants Ltd)
Bill Huynh (Marvell Inc.)
Joel Irby (AMD)
Richard Pistor (Curtiss-Wright)
Jan Schat (NXP Semiconductors) (joined 11:36)
Louis Ungar (A.T.E. Solutions)
Brad Van Treuren (VT Enterprises Consulting Services)
Carl Walker (Cisco Systems)


By email (non-attendees):

Jon Stewart (Dell)

2. Agenda

  • Eric moved to accept the agenda, seconded by Brad, no objections.

3. IEEE Patent Slides

  • {Slides 5-10}
  • Patent and Copyright slides reviewed.

4. Review and Approve Previous Minutes

  • {Slide 11}
  • Meeting #60, March 30 (draft circulated March 30)
    • No corrections.
    • Terry moved to approve, Eric seconded, no objections or abstentions → minutes approved.

5. Review Open Action Items

  • {Slide 12}
  • [38.1] Brad: Email brief instruction on using the simulation tool
    • Not much progress this week.
  • [60.1] Brad to raise differentiation of Translation from Transformation with P1687.1 group.
    • See discussion at 7a - COMPLETE.
  • Action Item Register: http://files.sjtag.org/P2654WG/ActionItemRegister.xlsx

6. Inter-group Collaboration

  • {Slide 13}
  • None.

7. Discussion Topics

7 a) Use cases

  • {Slide 14}
  • Clarifying what the purpose of the Use Cases was and how they would be used for the benefit of the standard document. Wish to avoid them becoming a "science project" in their own right.
    • Show the usage with 1687, P1687.1 and 1149.1-2013 and show differences in the hierarchies with each.
    • Show usage where none of these standards is available.
  • Are we need Use case or Examples in the standard? The 1687 standard only refers to "examples".
  • Use cases are abstract descriptions of problems.
    • The use cases will drive features that the standard must provide.
    • Then we can derive examples showing how those features should be used.
  • Moving outside the chip boundary is when loss of test access is likely to occur. Reliance is on the testability-involved interfaces being accessible at the higher levels.
  • Further notes captured on slide 34 of this week's pack (linked in the heading of these minutes).
  • Forum thread for comments on the outline: http://forums.sjtag.org/viewtopic.php?f=3&p=1444#p1444.

7 b) What is a “system” and what is not? (Feedback from P1687.1 group) 

  • Bullet points recorded during the earlier meetings are now moved to a separate reference file: http://files.sjtag.org/P2654WG/P2654_Reference_Pack.pptx.
  • Discussion points from P1687.1 meeting presented (http://files.sjtag.org/P2654WG/P2654_Meeting_60_Notes_for_P1687.1_Discussion_20200331.pdf).
  • In essence, P1687.1 maintain that their uses of "translation" and "transformation" remain unaltered.
  • Within the P1687.1 context, data content (payload) persists through both translations and transformations - this is necessary for lossless transfer of data to support diagnostics.
  • In P2654, we perhaps need to accommodate a "lossy" transfer of data; that is likely to be essential to support black-box COTS items. This is perhaps a fundamental differentiator between P1687.1 and P2654. We also need to acknowledge that lossy transfers must impact on diagnostic capability.
  • This means we still need to resolve a terminology for the lossy transformations in order to remain consistent with P1687.1.
  • Not considered in the proposed use cases is where the host directly command one sub-assembly to apply a stimulus and the expects another, different sub-assembly to observe the effect.
  • For (e.g.) a vendor to support diagnostic investigations, they may need to be able to replicate the tests that are performed in the end-use application. What is applied to the UUT will be after all the transformations etc., so the tests as defined at the host level would only be repeatable if all the other parts of the system were present.
    • It may be simpler to "record" the applied vectors at the level of interest than it would be to synthesize them from a system model.

8. Any Other Business

  • {Slide 15}
  • None.

9. Today's Key Takeaways

  • Lossy transformations discriminate P2654 from P1687.1.

10. Glossary Terms from This Meeting

  • None.
  • Carried over:
    • Translation may need to be defined.
    • "Interface" is missing.
      • No obvious IEEE accepted definition.
      • 1687 has definitions for specialised forms: Device Interface and Instrument Interface.
      • We may need specialised forms for Software Interface and Hardware Interface.
      • "Interface" is overloaded and requires disambiguation.
    • 1687.1: Transformation.
    • IEEE 1856: Sense - "Sensor" done, Acquire, Analyze not really defined.
    • Device - do we mean a packaged device? May be many devices in a package. "Device" is often used as a modifier, e.g. "device package", "device identification".
    • Use Case Context, Application Context
    • Legacy Infrastructure, SJTAG Infrastructure (placeholders for now, really for working group to define).
    • "Generators": May need to be qualified as "Test Generators" (used by the integrator/tester) and "Model Generators" (used by IP providers, interface designers, etc.).
    • AccessLink and DataLink descriptions will need to be revised.
    • See P1687.1's definitions on Slide 31 of the pack presented by Jeff Rearick on Jan 14, 2019.
    • "State", "Vector", "Sequence" and "Pattern" as proposed at April 8, 2019 meeting.
    • "Event", "Access Interface" as proposed at April 15, 2019 meeting.
    • 'Port' needs to be developed.

11. Schedule next meeting

  • April 20, 2020.
    • No meeting April 13 (Easter Monday).

12. Topic for next meeting

  • Recreating tests outside of the end-use hierarchy

13. Reminders

  • None.

14. List New Action Items

  • None.

15. Adjourn

  • Eric moved to adjourn, seconded by Terry.
  • Meeting adjourned at 12:10 PM EDT

Respectfully submitted,
Ian McIntosh