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Conference 7.286::fddi

Title:FDDI - The Next Generation
Moderator:NETCAD::STEFANI
Created:Thu Apr 27 1989
Last Modified:Thu Jun 05 1997
Last Successful Update:Fri Jun 06 1997
Number of topics:2259
Total number of notes:8590

1170.0. "DEFCN fails the self test in 35 degreesC air..." by TKTVFS::IDO (Naoki Ido, CSC/TOKYO, EWB, DTN 680-2456) Fri Dec 03 1993 07:17

Hi there,

I need some help for DEFCN hardware spec!
We have been seeing a problem that DEFCN (even it's without plastic cover) 
can't re-start due to fail the selftest if it's placed in high temperature 
(above approx. 35 degrees C) environment. However, if we don't toggle the power
 the DEFCN can continue to work fine even up to 51 degrees C. 
When the self test fails , the combination of LEDs is always as the following.

	Controller/backplane fault	RED
	Fan fault			RED
	Power supply DC OK		GREEN
	
	MGNT card fault			RED
	MGNT A_port Phy			off
	MGNT B_port Phy			off
	MGNT Ring Oper			GREEN

	ANSI6 line card fault		RED
	ANSI6 ports PHY	(all 6 ports)   off
	
The original problem reported from our OEM. They checked some of DEFCNs 
they have received because they have to ship those DEFCNs for a shipyard.
The temperature at the shipyard goes above 30 degrees C in summer time. They
therefore check whether DEFCN can operate such environment but within the 
specification.
The installation manual EK-DEFCN-IN-004 describes that DEFCN can operate 
between 5 degrees C to 50 degrees C if it's without cover, and 5 degrees C
to 35 degrees C if it's with cover. So, uncovered DEFCN must start without any 
failure.

We have confirmed the failure in our LAB. We placed several DEFCNs in heat 
chamber then checked it. Below is the test results.

Well, my question is..  What does DEFCN check anything special in the selftest?
Is this failing at 35 degC normal behavior?

Thanks in advance,
Naoki

***** DEFCN without cover*********
Air Temp.(DegC) in 	Air Temp(DegC) inside DEFCN 	Operation	Restart
 the chamber		(Heat sink on PWR)
------------------------------------------------------------------------------  
 10 			10 				OK		OK
 15 			15 				OK		OK
 20 			20 				OK		OK
 25			25				OK		OK
 30			30				OK		OK
 35			35				OK		Fail
 40			40				OK		
 45			46				OK
 50			51				OK


***** DEFCN with cover*********
Air Temp.(DegC) in 	Air Temp(DegC) inside DEFCN 	Operation	Restart
 the chamber		(Heat sink on PWR)
------------------------------------------------------------------------------  
 10 			10 				OK		OK
 15 			16 				OK		OK
 20 			21 				OK		OK
 25			26				OK		OK
 30			31				OK		OK
 35			36				OK		Fail
 40			41				OK		
 45			47				OK
 50			52				OK
T.RTitleUserPersonal
Name
DateLines
1170.1Looks like the DEFCN MFG power up problem we are working.NPSS::CIFELLIFri Dec 03 1993 09:2621
  This looks like the MFG problem that we have been working.  Although I
did not see a significant failure rate increase over temperature and I tested
units from 5c to 60c.  The test included Good DEFCN's, intermittent DEFCN's and
consistently failing DEFCN's.

   Right now we are evaluating the problem and are currently working 
implementation issues.

         Manufacturing  reported  a power up problem with the DEFCN
       after they  had  upgraded  the  test  line  units from old
       revision non OBM  backplanes  to  current  revisions which
       includes an OBM port.  Manufacturing sent me failing units
       which I used for my investigation.  It was found that when
       a DEFCN would fail, the Rom  code  would  not  finish  the
       startup  initialization  routines,  the  startup would not
       even  get to the dispatcher to start Selftest  diagnostics
       and/or Manufacturing mode  Diagnostic  Dispatcher  access.
       The  Rom  startup  code  was  failing  during  the  device
       initialization routine.  The problem  was found to be with
       the  combination  between the DCOK/RESET startup  hardware
       implementation  and the Rom Code DEVICE_INIT routine.
1170.2Introduction from last replyNPSS::CIFELLIFri Dec 03 1993 09:342
  I work for NPS (NIPG) Network Support group in TWO/LKG and I am the 
designated DEFCN Hardware Support Engineer for this problem.
1170.3When can we expect to get the fix?TKTVFS::IDONaoki Ido, CSC/TOKYO, EWB, DTN 680-2456Mon Dec 06 1993 01:0315
Tom,

Thank you four your prompt and detailed reply.
Would you please tell me the estimated date we can get the final fix? and How
do you think the fix is provided to field?  ECO, FCO, and as downloaded code, 
PROMs, or hardware? 
I am not sure whether we can fix this problem on code level or hardware 
compornent itself but I hope it is fixed by firmware code can be loaded with 
DECndu. Because I believe the OEM will request us to supply the fix for all 
DEFCNs they have. I think but it's not so many.

Do you need a CLD request from us?

Thanks again,
Naoki