On Tue, 31 Dec 2002, Eyal Lebedinsky wrote:

> "Peter C. Wallace" wrote:
> > Could be anything but my first guess would be a bad power supply, I've seen
> > several of those in my DS5000s. DCOK is active high AFAIK, you might check the
> > +5V and +-12...
>
> Well, I did check the voltages but I do not have a
> reference for the mobo that tells me what it correct.
> Here is what I measured (view from top).
>
>
>   ----------------------------------- front -------+
>                           +--+--+                  |
>        +-----+   +-----+  |1 |2 |    +-------------+
>        |     |   |     |  +--+--+ |  |             |
>        |  B  |   |  R  |  |3 |4 | |  |             |
>        |     |   |     |  +--+--+ |  |             |
>        +-----+   +-----+  |5 |6 |    |    power    |
>                           +--+--+    |    supply   |
>                                      |             |
>                                      |             |
>                                      |             |
>                                      |             |
>                                      |             |
>                                      |             |
>                                      |             |
>                                      /             /
>                                      /             /
>                                      |             |
>                                      |             |
>                                      |             |
>                                      |             |
>                                      |             |
>                                      |             |
>                                      |             |
>                                      |             |
>                     a b c d   e f    |             |
>                     + + + +   + +    |             |
>                     -------          |             |
>                                      |             |
>                                      /             /
>                                      /             /
>
>
> The voltages at the power feed are:
> 	B   0
> 	R   5.15
>
> 	1  12.24
> 	2 -12.14
> 	3   0
> 	4   0
> 	5   4.94
> 	6   0.20
>
> and at the pin headers I have
> 	a   0
> 	b   5.13
> 	c   0.02
> 	d   4.94
>
> 	e   0.02
> 	f   4.94
>
> All voltages measured against the chasis.
>
> So, it looks as if the voltages are fine, but I am not sure that the
> power OK signal is properly delivered. I assume this is one of 5/6?

Just looked at a 5000/240 (same power supply as 5000/200)

Looks like you are OK there (pin 5 is the DCOK line = white wire and ~5V means
DCOK...)

So must be something else thats a problem (though do check the 6 pin
connector, One of my 240's got flakey due to a bad contact in that connector)


>
> Now some speculations:
>
> I read somwhere that e-f is a jumper that clears the nvram. This does
> not match the fact that the chip is cleared by shorting pins 12 (gnd)
> and 21 (/rclr) and I verified that [f] is not directly connected
> to [pin 21] or any other pin on the clock/vnram chip.

If all of the LEDS stick on, the processer isnt getting anywhere near the
NVRAM, it must be a more basic problem (No reset, no reset release, cant
read boot ROM, etc, etc)

>
> In other places I read that the 4-pin brown header on other DS5k models
> has the pinout:
> 	a TRIG
> 	b GND
> 	c MFG
> 	d DCOK
> and that
> 	shorting MFG-DCOK will reset the machine
> 	shorting GND-MFG will enable some manufacturing tests
>
>
> --
> Eyal Lebedinsky (eyal@eyal.emu.id.au) <http://samba.org/eyal/>
>

Peter Wallace
Mesa Electronics