UPS Connections and use (FC2)

Mike McCarty Mike.McCarty at
Fri Mar 9 04:02:24 UTC 2007

I have a UPS which has faithfully served me for a couple of years,
but which I have never tried to control until today. I installed
the Linux software which was downloadable from the website, but
am not satisfied with the level of control afforded me. Essentially,
the software can log an event, play back the log, and wait
some specified period of time (30 sec. default) before initiating
a shutdown.

What I would like to have happen is this:

When the power fails, a timer is started, and I get notified,
preferably by a wall and an e-mail.

If the power resumes before the timer expires, then the timer
is aborted, and I get notified, as above.

If the timer expires, or the UPS indicates that the battery is
getting low, then I get notified as above, and the machine does a
"suspend to disc" followed by power down.

Upon power resumption, the machine does a "resume from disc"
if a "suspend to disc" is found. If no "suspend to disc" is
found, then a normal boot ensues.

The information supplied with the UPS is MS-centric, but should
be adequate to ascertain what needs to be done. First, the
software can find the UPS via a straight-through 9 pin serial cable.
I have verified this, though I uninstalled their software. They
do claim that a "special" cable is needed. I note that not all
functions work with a straight-through cable, so perhaps they
are using the funky TxD on Pin 1. But it can notice that the
UPS is On Battery at least.

Second, the UPS can be used with MS using the UPS manufacturer's
"special" software, or the "standard MS setup". The MS setup specifies:

Power Fail/On Battery: Negative
Low Battery:           Negative
Remote UPS Shutdown:   Positive

I suppose that this means that Power Fail, Low Battery,
and Shutdown are indicated/controlled by some of the modem
control signals, like DCD, DSR, and DTR, but I don't know what
the associations are, nor how to make something respond
to changes on those lines and take appropriate action.
My guess is Power Fail /DCD, Low Battery /DSR, and
Remote Shutdown DTR.

Third, I have a desktop, not a laptop, and so I wonder
whether suspend to disc can be done with my machine.
I use FC2 which I realize is not supported, but I suspect
that this aspect of behavior has not changed significantly
in recent times.

Is it likely that I need a special (APC compatible) cable?

Would someone please help me to configure my machine?

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