Hi Folks, Your expertise and wisdom may help me clarify thoughts on the following. I'm contemplating buying a couple of UPS units, at the very cheap end, so no comms to the computer which could be used to initiate a programmed shutdown if the mains goes off. So in turn I'm contemplating rigging a little circuit which would supply a signal to a serial port while the mains was on. The germ of the idea is to use one of those very cheap power converters which can deliver a DC voltage chosen from (say) 3V, 4.5V, 6V, 9V, 12V, and set it up so as to put say 12V between 2 pins on a serial port, when plugged directly into the mains. Then it would be easy to have a little script running in the background which would monitor the lines on the serial port, and initiate a shutdown if the voltage dropped to zero for (say) more than a minute. That's the bare bones of the idea, and indeed enough to define a basic soldering-iron job! But I'm not sure I'm being circumspect enough here, so would welcome comment! With thanks, and best wishes to all, Ted. -------------------------------------------------------------------- E-Mail: (Ted Harding) <Ted.Harding@nessie.mcc.ac.uk> Fax-to-email: +44 (0)870 094 0861 Date: 31-Oct-06 Time: 20:26:50 ------------------------------ XFMail ------------------------------