Not receiving BUSY message during Call

15 thoughts on “Not receiving BUSY message during Call

  1. Hello!

     

    I am currently using the Telit GL865 moduleto make voicecalls. I have used at#dialmode = 2, in order to get verbose satus updates about the voicecall.

     

    The calls work fine, but for some reason the module never gives a "BUSY" indicator if the receiver of the call hangs up without answering for example. Basically the call simply hangs and while I can hear a busy tone, there is no indication on the uart line. 

     

    Any help with this would be much appreciated. I really need to know the voicecall status and whether or not somebody has answered or declined the call.

     

     

     

    Joonatan Renel

     

    1. If the module has ATX0 the you’ll get NO CARRIER in such case, if it has ATX1…4 you’ll get BUSY.

       

      1. It seems that should be the case, but right now I’m getting neither answers. I tried setting ATX to several different values, but I’m not getting the BUSY or NO CARRIER message. There is no notification at all in case of a busy signal.

          1. Test with 16.01.150 (check your email please).

             

            Enable call monitoring with AT#ECAM=1, see if this is working.

          2. I’ll see if I can do a firmware update on the module, although this might take a bit of time. I noticed something strange about the BUSY message though. It seems that if I send a command to the module after the module gets a busy tone then the BUSY message gets appended to the front of the answer. 

             

            I checked for software problems, but it seems that there is nothing there. Messages CONNECTED, DISCONNECTED, RELEASED,  etc. get transmitted just fine.

             

             

            I’ll see about the firmware thing, since the module is already sitting on a  PCB ,then it will take some effort to get it to update it. 

          3. Also with AT#ECAM=1 I get the same behavior. The ecam message is not transmitted in case of a BUSY signal. It works with all other cases though.

          4. I checked and there are no other characters besides CR. Actually I used to have this problem before. I mistakenly sent <cr><lf> characters and this caused the call to be dropped in a lot of cases. But I fixed it and it worked fine from there on.

             

            Do you know if there is a way to hard reset a module to all factory default values. Right now I’m afraid that somethign has gone wrong in the module settings. I actually tried using a different PCB with virtually the same program and same firmware and it displayed the BUSY signal just fine.  Maybe a complete reset would change something? ATZ seems like it doesn’t reset a whole lot of things on the module.

             

            Currently this is really strange, we have two PCB-s with the same GL module installed, using the same software and the same wiring. Except one module is behaving differently. I thought maybe it was a problem with hardware flow control, but this is disabled on both modules. 

          5. See AT+CMAR for a complete NVM formatting. A firmware upload will give a fresh module with factory settings as well.

          6. I did a firmware update with the file you sent me, but the issue is still there. Currently I am directly communicating with the module and there is no controller attached. I only use the command AT#DIALMODE = 2 and then I call with ATD<number>; Still I can hear a busy tone, but no BUSY message comes out unless I send another command.

             

            Example :

             

            OK

            ATD***********;

            ATD************;

             

            DIALING

             

            RINGING      // Then the call is rejected and I hear a busy tone through the speaker.

            AT+CSQ?    //Only after sending AT+CSQ message, I receive BUSY code.

             

            BUSY 

             

             

             

            Is this kind of behavior the factory default? Is it supposed to be acting like this? I mean if it is supposed to do this, then how do I let the microcontroller know if a call has been terminated. Only way right now is to periodically poll the controller for a BUSY signal by using AT commands. The problem is that this will terminate the call even if it is currently ringing or dialing.  

             

            Is it possible that the module itself has been damaged somehow?  

          7. Fixed the baudrate to 9600. Still no change. Is it possible that somehow there’s an issue with the SIM card? It’s starting to seem that the module itself is broken.

          8. Hi Joonatan,

            please verify your set up. See below my log:

             

            [TX] – ATX0<CR>
            [RX] – <CR><LF>
            OK<CR><LF>

            [TX] – ATD3392072738;<CR>
            [RX] – ATD3392072738;<CR>

            [RX] – <CR><LF>
            DIALING<CR><LF>

            [RX] – <CR><LF>
            RINGING<CR><LF>

            [RX] – <CR><LF>
            NO CARRIER<CR><LF>

            [TX] – ATX1<CR>
            [RX] – <CR><LF>
            OK<CR><LF>

            [TX] – ATD3392072738;<CR>
            [RX] – ATD3392072738;<CR>
            <CR><LF>
            DIALING<CR><LF>

            [RX] – <CR><LF>
            RINGING<CR><LF>

            [RX] – <CR><LF>
            BUSY<CR><LF>

            [RX] – <CR><LF>
            DISCONNECTED<CR><LF>