Controlling a relay via cellular phone.....

GSM

the

I wouldn't want a computer that rebooted every time it's telephone number rang, so I would plan on sending a coded tone signal. The buzzer signal could be routed to the push to talk (answer) button so it would automatically answer every call, but off-hand I don't know how to hang up, if you are planning to remote detonate a bomb then you won't need to hang up. Paranoid? I AM THE KING OF PARANOIA!!

If it's locking up, the printer port makes even more sense. Output a pulse at a regular interval. If it stops, your controller resets the computer. A simple missing pulse detector and a little thought will show you how it works. Think of it as an external watchdog timer.

You've never used Windows ?

Graham

On Thu, 13 Jul 2006 01:50:45 +0100, in message , Eeyore scribed:

Er, Graham, he said *functional.*

case

Did anyone ever tell you about the huge voltage potential between the electron gun at the back of your monitor, and the screen you have a few inches from your nose. RUN, RUN

tapwater Professional Chicken Plucker

up,

Isn't the correct spelling "PHUCKER" ?:-)

...Jim Thompson

-- | James E.Thompson, P.E. | mens | | Analog Innovations, Inc. | et | | Analog/Mixed-Signal ASIC's and Discrete Systems | manus | | Phoenix, Arizona Voice:(480)460-2350 | | | E-mail Address at Website Fax:(480)460-2142 | Brass Rat | |

You can buy cards that implement the WDT function for PCs.

Best regards, Spehro Pefhany

Buy? Wait, I have to turn the crank on my home-made electrical generator. There, that will hold it for a few minutes. What means this word "buy"? Thank you for the information, and if I ever get some money I will learn to buy stuff.

case

You can spell what YOU do any way that you want to.

case

Then maybe he needs to run an OS that does not need rebooting.....

Meindert

I can't tell if it works for all cells, but it's worth a try.

Most Cell modems give out a RING command on their TX lines when a call comes in (few serial bits). The TX line can usually be found on the data cable connector [1]. You can then use this line, perhaps with some diode capacitor config, to switch a transistor, which in turn can switch your relay. (or you can try putting the transistor directly where your reset button is?). Be sure not to take too much current from the TX line.

I've never tried this at all, but it's very easy to find out if i was right or wrong.

Goodluck,

Jasper

------- [1]

Even the old OS in ROM computers needed rebooted at times. The only computer that never needs to be rebooted has already been tossed into the pile to be recycled.

the trick would be putting the pulse emmission in a place where it can't happen when the computer needs to be rebooted.

I've seen machines with a totally hosed user interface continue to serve other tasks

Bye. Jasen

even windows 95 could runs 42 and a bit days before it locked up

Bye. Jasen

set the phone to "do-not disturb mode", put your phone number in the priority list, then it'll only ring when called from your phone.

other peoples wrong numbers will be harmless.

Bye. Jasen

Mmmm..... my linux server hasn't been rebooted for over a year.....Still running.

Meindert