FAQ on Voice Call and SMS

2023-10-27

What should be done if it fails to make a call? ？

  • For CAT1 modules that only support 4G, you need to use firmware that supports the VOLTE function. Moreover, only under the circumstance that the SIM card is equipped with VOLTE function can the Voice call be executed.

  • Confirm whether it can register to network normally and it is on debt.

  • Whether the firmware supports the VOLTE function. Only version that supports the VOLTE function can make voice calls.

How to activate the VOLTE function?

For CAT1 modules that only support 4G networks, there is no need to activate VOLTE since the SIM cards of China Mobile and China Unicom support the SMS. While for SIM card of Telecom, only when the VOLTE is activated can the SMS be used.

See several methods to activate the VOLTE function,

  • Log in to the app of operator in mobile terminal to activate.
  • Log in to the official website of operator to activate.
  • Call the customer service number of operator to activate.

Does CAT1 support video calls?

No.

Does the module have a white-list setting for incoming calls?

No. However, it is capable to set one white-list via corresponding script. For any incoming call that excluded from white-list, please hang it up directly.

It will occur echo when making a call via 4G module

Please confirm whether the speaker's sound is mixed with the Mic's sound. It is available for you to check the echo via the headphones.

Does the IoT card support SMS function?

Generally speaking, the IoT card does not support the SMS function. For specific, please consult the IoT card supplier.

Does it support MMS function?

No.