pybytes deepsleep

  • Hi all,

    I've run into an issue using pybytes on my LoPy4 with Pysense shield.
    I would like to get data from sensors, send them to Pybytes and go to deepsleep.
    I do have sepadate funcions to get the data from sensors and to send the data.
    Simplified code without any definitions and library imports:

    sensorData = getSensorData()

    The getSensorData() returns JSON dictionary with all the sensor data.
    The sendData() looks like this:

    def sendData(data):
        pybytes.send_signal(1, data['batt'])
        pybytes.send_signal(2, data['temp1'])
        pybytes.send_signal(3, data['press'])

    (two dots represent more lines in the function, 9 values are being sent, wanted to save some space :) )
    The problem is that calling sendData() jumps out immediately and the actual data sending process takes on later. From what I understand pybytes.send_signal() sets up a new thread with given arguments and is done.

    So when I run the code, LoPy goes to deepsleep before it actually sends out any data to Pybytes.

    Is there any flag or variable I could check to see if my Lopy board is still sending out the data and in that case wait before going to deepsleep??

    Something like:

    sensorData = getSensorData()
        if not "pybytes_still_sending_data":

    Possible workaround may be to put time.sleep() for like 20 sec before the deepsleep, but I would like to avoid this "solution".

    Thank you,

  • I came up with a solution to this that for the moment seems to work. It is based on checking the length of the outgoing message queue (will fail if no mqtt connection)

    for _ in range(10):
        in_queue = len(pybytes.__pybytes_connection.__connection.__mqtt._msgHandler._output_queue)
        if in_queue == 0:

  • I have hit this too. Maybe an optional callback parameter to send_signal which gets executed when done?

  • Hi,
    Ill put this on the feature list!

  • @j_mor

    I had like to know the answer to this too.

  • Would love to know this as well, or if there's any way to get confirmation that a message/signal was sent (with_ack)?

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