Stream of rubbish in AT channel after turn on GL865

6 thoughts on “Stream of rubbish in AT channel after turn on GL865

  1. Hello!

    I have the next question ).

    We can’t use Auto-Turning ON the GL865 proccess which is shown in "GL865 Hardware User Guide"(page 16), because we use fwupdater utility.

     

    So we want just turn on module supply and check that PWRMON is ‘1’. 

    But when we do it, at once after turning on module sends some rubbish of bytes throught AT channel, about 30 – 80 bytes. Is it ok? Or there are some variants how to force module don’t send rubbish after turning on?

     

    When we use  Auto-Turning ON the GL865  no rubbish in AT channel after turning on. But it doesn’t fit us, because we must sent AT command during turning on, gsm module’s loader doesn’t starts up.

    1. can you describe exactly the sequence used to turn on the supply, without turning on the module? Do you apply only VBATT_PA to the module? In that case PWRMON should be 0.

  2. At first about  scheme:  VBATT_PA(37), VBATT(37) – VCC = 3.6V.

    Pins: 32, 33, 35,36, 46 – GND. 

    Sequence:

     – turn on a module(VCC is high level)

    – check PWRMON, if it’s high level then a function return ‘true’, if low power turn off.

    –  if the function return true I read USART and it returns some rubish at once aftern turning on.

    I don’t use any delays.
    I need it because of  using FWUpdater for gsm module.

    In documentation is writtent than we must wait 1000 m-seconds,  the  V_AUX / PWRMON pin will be at  the high logic level and the module can be consider fully operating. But it becomes high very quickly.
    1. Try waiting 1000ms after the PWRMON becomes high, before reading the UART.

      But I still don’t understand what do you mean with : "When we use  Auto-Turning ON the GL865  no rubbish in AT channel after turning on."

       

      What is it different from the turn ON procedure described above?

      1.  But I still don’t understand what do you mean with : "When we use  Auto-Turning ON the GL865  no rubbish in AT channel after turning on."

        Auto-Turning ON the GL865 algorithm "Telit_GL865-DUAL_QUAD_Hardware_User_Guide_r5", page 16. If I do the same no rubish during module turning on.

         

        What is it different from the turn ON procedure described above?

        Auto-Turning ON the GL865 algorithm uses delays and sending AT command.

        1. I cannot see these bytes coming out from the module at power on, but can you verify if fixing the baudrate with AT+IPR, and saving the parameter with AT&W0, can help?