I have an audio device that plugs into a phone line. I want to create a vb.net app that will continuously monitor one of the ports for DTMF tones. When it detects a DTMF tone, i.e. someone is dialing a number, it performs an action. It doesn't actually have to decode the tones, just detect when one is dialed. Can someone give me code that will do this?
The device is actually a Telephony card but I can't use TAPI because the card itself does not actually pick up the call. The card has WAVE drivers so it can be set as a Default Recording Device in Windows.
Alternatively, if someone can tell me how to detect a dial tone or dtmf tone with a Telephony device that is passively monitoring a phone line (tapping it), that would be good too!