Minute minder

Hi how can i add a minute minder like in cell phones?

Where do you want this information, on the phone or by dialing a specific extension?


I will have call limit of 5 minutes and i want the caller and the called to receive a beep every minute (warning) without stopping the conversation. Can i put this on the dial plan? Or in my phones? My voip phones are grandstream BT200.

This beep works like in cell phones a beep for every minute.

I found this option L() on dial but i can´t put it to work i using it like so 1001,3,Dial(SIP/1001,6,L[300000:10000:30000])

can someone help me with this option? it seems to me that i can had a minute minder with this?

exten=> 1003,1,Set(LIMIT_PLAYAUDIO_CALLER=yes)
exten=> 1003,2,Set(LIMIT_PLAYAUDIO_CALLEE=yes)
exten=> 1003,3,Set(LIMIT_WARNING_FILE=beep)
exten=> 1003,4,Dial(SIP/1003,L(360000:300000:60000))