Signaling Tones Mode AT#STM

One thought on “Signaling Tones Mode AT#STM

  1. Q:

    I’d like to know what the purpose of the commands "Signaling Tones
    Mode AT#STM" and "set hands free side tone AT#SHFSD ".  What are they
    respectively used for and how can the developers get the results?



    The signaling tones enable/disable applies to the tones usually played
    on particular events uch as call established tone, call dropped tone,
    call ended tone, network registration loss, network registration regain,
    battery low (if power supply goes below a certain threshold) etc.. For
    some applications these signaling tones might be unwanted and therefore
    they can
    be enabled/disabled with the #STM command.
    About the
    Hands free side tone: the side tone is a sort of local echo of the
    microphone signal that is reported on the earpiece, this is always
    required when the voice call is made by human beings (just to let the
    speaker hear what he is talking about), but it might be disturbing when
    the voice call is managed by a machine. Therefore it is possible to
    enable/disable it with the #SHFSD command.