M65 Blank SMS Receive

We are using M65 Modem in one of our product. When we send SMS from mobile to the device and wait for the reply so we see the message at CLI UART but receive blank SMS on Mobile.

How do you send SMS, using AT command? Call an API function? Please provide more information so that we can judge. Here are some common solutions that can be adopted.

If the instruction is AT:

  1. Recommend using AT+CMGF? This command returns the current SMS mode, 0 for PDU mode, and 1 for text mode

  2. Use the AT + CSCS? This instruction returns the character set. For English text messages, “GSM” is recommended as the TE character set

  3. Try using numbers as text messages and see if Mobile can receive the message. If so, it may have been sent in the wrong format

Finally, can the module normally receive and read SMS messages? If possible, you are advised to check whether the content format of SMS messages meets requirements