Author Topic: Paralell port project for burglar alarm on xp  (Read 10539 times)


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Paralell port project for burglar alarm on xp
« on: May 25, 2011, 09:48:41 pm »
enjoyed your site. I would like a program or driver where the parallel port detects a pin change with connection to my burglar alarm. I would connect to pin using an optoisolator and when it changes state, Hi or LO , i would like it dial my phone and let me know of the occurence , also I could listen in thru the Laptop's mic. Running XP. Ive thought maybe a macro to dial SKYPE. How would i get the change of state on paralell port to trigger SKPE to auto dial? I know there are autodialers out there. thanks for your time.

Jan Axelson

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Re: Paralell port project for burglar alarm on xp
« Reply #1 on: May 25, 2011, 10:16:40 pm »
For tools to read port bits, on this page:

scroll down to inpout32.dll

To detect a change in port state, your program can read the port repeatedly in a loop. This assumes that the state change will persist long enough to detect it. Writing a program that uses a hardware interrupt would require a low-level driver; DriverX is one option:

Another option is to use a serial port and detect a change on a flow-control line (.NET SerialPort class).

« Last Edit: June 29, 2015, 10:23:54 am by Jan Axelson »