As simple as it is, you need an external controller for that switch that will be signalled to turn the bell on or off. Only when the controller is specified is it possible to say what the computer has to do.

If you have a custom computer supplier (instead of the usual off-the-shelf trained monkeys) , they should be able to tell you which controller to get and it will have a manual that will tell you how to operate it from the PC.

On second thoughts, because you are going to use a relay, if using unix or linux you just have to write lots of FFFF (hex) to the relevant device in /dev.

More update: I also thoroughly agree with the replies that suggest isolating the port from the bell circuit. I had an idea for isolating with a rectifier although I am scratching that because it would only (literally) half work for a/c.

-M

Free your mind

In reply to Re: Using Perl to make a hot-lead from any port by Moron
in thread Using Perl to make a hot-lead from any port by Petras

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