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Re: TASS UPS, Tech Note.

On Mon, 18 Aug 1997 15:12:54 -0500 (CDT), droege@wwa.com wrote:
*>Chris and all,
*>I guess I live in a different world.  No matter how I design something
*>if it is not absolutely fool proof, someone will figure out how to 
*>connect it up wrong.  
*>On Mon, 18 Aug 1997, Chris Albertson <chris@topdog.logicon.com> wrote:
*>>1. Tom wrote about a lack of a standard connector for re-seting a
*>>PC.  Every PC I have seen, going back to the first IBM 8086
*>>powered PC can be reset by shorting two pins on a standard 0.1
*>>inch spaced header.
*>Yes, I know about these pins.  Unfortunately, they are *inside* the
*>computer and cannot be accessed by plugging a standard connector on
*>the *outside* of the computer.  The watch dog board is a way to get
*>at it in a formal, standard way.  Sigh!  I prefer solutions where 
*>someone does not have to know how to find the reset pin pair (and
*>in the process not get across the disk running pair, or the turbo
*>pair, or the ...)
*>Tom Droege

I dont' know that the cost of a watchdog board is justified ONLY as
a way to avoid looking for the reset pins. Most motherboards today
lable their pins with text. And one can trace the wires from the front
panel reset button. Of course there is a reset line on the bus that
could be brought out to a connector on your interface card, but that
would be a bit of reengineering at this stage.

As for finding the reset lines: It's a one-time setup,
presumably the site can find somebody who can manage this bit, especially
if you (somebody) provided the "standard connector" with internal cable and
whatever bit of electronics was needed (say a relay or timer or whatever).
Some judicious shopping around may find this solution already "invented".

A more "robust" reset would be to shutdown the PC's power supply
via an AC disconnect. It would have the additional virtue of shutting
down the AC supply - sometimes they "hang". I had suggested a
mundane AC daily timer control that would shutdown the PC *every day*,
an assured restart at a convenient time resolves a number of problems.
Some may not like this solution, but it costs $10 and is fairly idiot
proof, and it saves energy if you power down for a signifigant period.

Herb Johnson

***** I do not want bulk email. Automated bulk mailings prohibited. ****

Herbert R. Johnson                      voice/FAX 609-771-1503 day/nite
hjohnson@pluto.njcc.com                 Ewing, NJ (near Princeton) USA

                 occasional amateur electronic astronomer
               supporter of classic computers as "Dr. S-100"
   and senior engineer at Astro Imaging Systems: old photons to new bits!