VAXstation/MicroVAX 2000 CPU/FPU overheating?

[Allison]

>
>Subject: Re: VAXstation/MicroVAX 2000 CPU/FPU overheating?
>   From: "Dave Dunfield" <dave06a at dunfield.com>
>   Date: Sun, 02 Mar 2008 09:35:46 -0500
>     To: "General Discussion: On-Topic and Off-Topic Posts"	<cctalk at classiccmp.org>
>
>> > The extended system tests 101, 102 and 80000106 will not test the FPU
>> > - this may be normal, I don't know. The docs say they will test all
>> > hardware which is installed - this may mean that the FPU is not being
>> > full detected... I don't know.
>> 
>> Is the FPU socketed?  If so, can you remove it, and what the boot and 
>> test output looks like?
>
>Aw, I wish ... the only things socketed on this board are the ROMs and
>the serial device. The CPU/FPU are 68 pin surface mount devices.
>
>
>> If you can't remove the FPU (likely), the diagnostics would probably be 
>> complaining about it not working...
>
>Which is the main reason I'm not 100% convinced the FPU is faulty. But I
>can't get the extended disgnostics to test it, and I don't know how "good"
>it has to be to pass the basic startup test.

It doesnt other than not jamming the busses.  VAX does nto need the FPU 
to boot.

>
>> I've not had my uV2000 opened up (or even turned on yet...), but that'd 
>> be my next step.
>> 
>> Maybe if I have some time, I'll dig mine out and try playing with it.
>
>If you do open it up and have it to the point where you can scope signals,
>please contact me ... I've got a few questions about the signals I see in
>mine. I've also got a couple of questions about the diagnostics and the
>FPU that could be answered with a running system (only the console ROM
>required).
>
>If anyone has a running VS2000 or UV2000 and is willing to open it up to
>help me do some comparison testing, here are the things I would most like
>to know:

I had mine open for temperature testing, thats were I got the 58C
from.  I should play with console boot later.

>[For best results, it would be good if the system were configured to match
>mine - all expansion boards, drives, peripherals etc. disconnected, and
>the uVAX/VS jumper located about 3" directly behind the BNC ethernet connector
>set to the uVAX position, which is AWAY from the BNC connector.]

Sounds like mine more or less.  I cant scope it at this time as the wide 
band scope is burried and likely not going to emerge for a while.  I 
have a 20mhz dual trace for most work handy as it's smaller but it 
will not see a 40mhz clock well nor do I use it for that kind of work.

Allison

>[To run the extended diagnostics 101, 102 and 80000106 you need a DB-25-F
>connector installed (on the DB-25-M connector on the board) with pins 12
>and 18 connected together]
>
>a) Whats tests are run by the "T 101" command?
>   Mine runs: C, B, 7, 6
>
>b) If you run "T 80000106" and then enter '9' at the "? >>>" prompt,
>   do you get any test output other than the CPU designation title?
>
>[For the following, I would like a description of the waveforms
> observed, waveshape, amplitude and frequency where appropriate]
>
>c) The 40Mhz clock at the W4 jumper (right beside the 40Mhz oscillator
>   "can") - with the jumper installed?
>    I see 40Mhz sine wave, about 2.3v p-p
>
>d) The 40Mhz clock at the W4 jumper pin closest to the oscillator
>   "can" with the jumper removed?
>    I see 40Mhz sine wave about 3.4v p-p
>
>e) Pins on FPU
>   44 - I see about 160mv irregular square wave
>   59 - Same as above
>   15 - I see 40Mhz at about 160mv
>
>Dave
>
>--
>dave06a (at)    Dave Dunfield
>dunfield (dot)  Firmware development services & tools: www.dunfield.com
>com             Collector of vintage computing equipment:
>                http://www.classiccmp.org/dunfield/index.html