Thanks for the reply "dawg"...lol...To give you an idea of the system as a whole it will be centered around a house or business/office with some sensors inside and some outside (so, various locations) and this gadget i need has to take input from all sensors and send them to 3 outputs: 1) A local panel board where switches that have been triggered are indicated by LEDs and buzzers; 2) the user's interweb connection (but automatically so that the info about triggered sensors gets to our server...i.e. they dont need to be bothered by it coz they have the panel...) and 3) in case they dont have inet at home an SMS text sent out to our server or SIM card as well (we already have the stuff needed to relay the message to the subscriber)...And, ya, we might use remote sensors that transmit thru RF (radio frequency is what you meant, right?) but some by wire as well or maybe even both for a failsafe. So, you're saying if the subscriber has a PC with a parallel port we could write code and the customer's computer will serve as this "gadget"?...coz i know someone who writes excellent code...Anyhow, what about the text messaging to our server?
Thus, if i have a parallel port with custom software and BCD code (i dont know what that is), an interface circuit for the port (how to build that?) and both RF and hard wire inputs that would be "it"? I'm kinda getting a picture formed but still very fuzzy...BTW, what would i type into google to search for ready made gadgets that do all this...? Thanks