How to detect the busy ZAP channel


I have a problem with dectection of busy channel
I use Ambient Md3200 card (X101P) .
and I have 3 extn with asterisk
when some user is dialing the number over PSTN network . then it should be detected and at a same time some other user try’s to dial a number over pstn then that user get a message like line busy .try after some time.

is it possible with X101p card.


firstly, did you search the forum, or even look through the other threads. this was discussed only yesterday !

Asterisk will prevent you trying to use the Zap channel if there is already a call going through Asterisk on the channel, but there is no tone recognition or channel status otherwise. if the line is in use by a device ‘outside’ of Asterisk then it will dial anyway.