SIM7080G CAT-M/NB-IoT+GNSS Unit Issues

  • Hello everyone,
    I come to you because I have a problem with this module, I can not make it work, the UIFlow method does not work nor arduino. When I give him an AT command I have nothing in return. I don’t understand because I have a NB-IoT SIM card that works.
    Can you help me, please?

  • Hello @KevinMartins

    which M5 core device are you using? M5Stack (Base, Fire, ...) or M5Core2 or M5CoreS3?

    Also make sure your SIM card has the PIN disabled.


  • #include <HardwareSerial.h>
    HardwareSerial Comm(1);

    Comm.begin(115200, SERIAL_8N1,TX_pin,RX_pin); // TX RX

    Comm.print("AT+IPR=115200\r"); // Set text mode

    Last command should return an OK. If not, it could be that you have mixed up TX and RX pins or a power issue.

    To read the reply from the module you could use something like this :
    while (millis()<wait_until)
    while (Comm.available())
    if (k<buffer_size-1)
    if (strstr(Receive_buffer,StopCharArray)!=NULL)
    //Serial.println("OK found");
    // SIM7600_Error=0;
    return false;