Dan Wagoner is playing around with connecting an Arduino to his Asterisk system.
I’ve been able to get Asterisk grab info about sensors connected to an ethernet-enabled Arduino, but how about the other way around? What if you could allow your Arduino to make outbound calls through your Asterisk system to make a make-shift alarm system, or over-powered doorbell? Well, wait no longer! Here’s how it works:
Asterisk: A php script lives on your Asterisk server (hosted up by apache) that, when it’s accessed, checks to make sure the client accessing it matches a pre-defined IP of your Arduino. If so, it creates a call file with the criteria that you configure to call a number of your choice and drops it in the Asterisk outgoing queue directory, triggering Asterisk to make a call.