Cheap or free auto-shutdown setup

David Mason mason at oct1.UUCP
Wed Oct 3 18:26:34 AEST 1990


In article <1030 at bilver.UUCP> bill at bilver.UUCP (Bill Vermillion) writes:
>Why couldn't you just use a cheap relay connected to the mains power
>source.  Then connect pins 2 & 3 of the rs232 to a pair of contacts that
>are closed when power is on.  Then just send something out and see if it
>echos.  If it doens't come back to you, the power is off!

Or even easier.  Get a mains/25 volt ransformer (12 volt would probably
do, and can be bought off the shelf very easily) and wire the live 25
volts into DCD of a serial port.  Open the port with modem control. 
When the power drops, the port closes, and some program takes ap-
propriate action.  Haven't tried it, but it seems easy enough.
--------------------
David               |      mason at oct1.UUCP (David Mason)
                    |      olsa99!oct1!mason at ddsw1.mcs.com

~~~~~~~     Has your C2 locked you out today?    ~~~~~~~



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