Mangoh voiceCall does not work


Hello everyone,

I’m currently working on a mangOH Red, a Sierra Wireless WP8548, and the Legato platform. I’m using Legato version 17.11.0, and am trying to write a program that uses the mangOH board to make a phone call from my cellphone to the board and then try to make some actions (in the future, when i’ll make it work)

Problem is I would like first to make the application mangohVoicall that you provide ( to work to make a phone call from the device to my phone. Not sure it should work on both mangoh Red and mangoh Green?

I correctly installed the app, and followed the instructions in the README :

  • Make sure that you use a voice SIM and not a data SIM for this tutorial: i used the sim provided in the kit, not sure how to know if it is a “voice” SIM?
  • Insert a headset audio jack into CN500 to listen to the audio.
  • Mangoh must be registered on Network with the SIM in ready state : seems to be in ready state when I do “cm sim info” or “cm sim status”
  • Make sure voiceCallService is started by entering: app start voiceCallService : OK.
    Are there any other apps that need to be started? or stopped maybe?
  • Check "logread -f "
  • Execute app : app runProc mangohVoiceCall --exe=mangohVoiceCall –

When I check the log :

  • In the main function, phone number (“MyPhoneNumber”) is correctly collected (passed as a parameter)
  • No assert when “le_voicecall_start” is called.
  • But in the handler function we should call “openAudio” going through “LE_VOICECALL_EVENT_CONNECTED”, and instead we are going through the following states :
    - New Call event: 0 for Call 0x10000001, from “MyPhoneNumber”
    - New Call event: 2 for Call 0x10000001, from “MyPhoneNumber”
    => DisconnectAllAudio

Note that I can send a sms from the device to my phone without any problem, and that I can command for example LED D410 (WP_GPIO_7) by sendind a sms to the device.

Any idea where the problem can come from?

Thank you very much in advance for any hep you can provide me,


Make sure that you use a voice SIM and not a data SIM for this tutorial: i used the sim provided in the kit, not sure how to know if it is a “voice” SIM?

I also don’t know how to check if your SIM is voice capable or not. What I do know is that the Sierra Wireless SIMs bundled with the mangOH boards are data only.


Thank you very much for your answer David, i’ll try with another SIM that can handle voice communications as well then, and see if it is working better.



Hi Fabrice,

I’ve written an IVR that runs on the WP8548. It receives DTMF tones from a voice call RX channel, and then plays back pre-recorded audio samples over the voice TX channel.

Works on the WP8548 OK, but not on the WP77 (because voice is not yet supported).

But … you do have to have voice enabled on your SIM card. The easiest way to ensure this is to buy a ‘phone’ SIM card and add data to it - don’t buy a ‘data’ or ‘wireless broadband’ SIM card as it’s been my experience that telcos won’t/can’t enable voice calls on a data only service.

ciao, Dave


Thanks David for your answer,

I was trying to figure out how I could manage to establish a voice call through data connection (for example like it is done with Whatspp or Viber) I don’t know if it is possible, maybe it’s not, and it’s mandatory that I to use a SIM card that features voice calls.

Thanks for your answer anyway,


Hi Fabrice,

No Problems.

You shouldn’t have any problems trying to do a Voice over IP call if you’ve got the data service set up OK. That shouldn’t need a voice sim.

You should be able to plug into the analog audio service to get a PCM stream that you can then pipe into your VoIP stack. That’s essentially what I was doing with the playback on the IVR I wrote.

ciao, Dave


Hello Fabrice,

I am using a WP7504 on the mangOH Red, and am also experiencing problems with the voice call demo. Did you succeed in getting the voice call application to work on your mangOH?



It turns out that the firmware for Sprint does not support voice calls, so this was my problem. Thanks, @rkirk.