LTE Modem crashes

  • Is the GPy project over? Seems like individuals with serious issues are getting very little in the form of help. I am having a lot of LTE issues myself. For example, LTE modem "not responding (OS faults)" or crashes when accessing data from website connections. Seems like this product isn't mature enough yet? I would say for the most part it is close. But has some bugs under the hood with LTE connections.

  • I have this as my LTE version:

    That seems the most up-to-date version I can find. I will add the ping test. That my prevent crashes in the post sends.

  • @Richard-Johnson As Don says there can be a more than a few moles to whack when it comes to LTE. We've been fine tuning our code for a couple of years now. The only problem we haven't been able to crack is the occasional loss of the lte in weak signal situations. It's a strange one in that the micro thinks there is an lte (if not lte: lte=LTE() doesn't execute) but detach, disconnect & deinit all throw an OSError. Our best work around to date is to do a 1s deepsleep which rids the micro of the non functional lte then create a new one (ours is a battery powered application & it's important that we have a working lte prior to our normal 10min deepsleep so we can power down the modem).

    A few brave souls have tried bypassing the lte class (, but we've never had much success with that approach.

  • @Richard-Johnson Well, threre are a lot of things to, but two impotnat that we do is to ping an IP-address to test the connection, and we always detach the connection after we send data.

  • @Don-iot Do you have any Do's or Don'ts to recommend? Any tests to run to verify internet connections before trying to use it? /What rev of FW are you using? Are you recommending I update the FW?

  • @tlanier Ouch! I hope I don't need to go that far. I think for the most part I am catching the exceptions and restarting the module. But It does throw a WDT error on sending a POST message out after shutting down the LTE connection, waiting for 50 minutes, and restablish a LTE connection and then retry to send the POST request.

  • What we ended up having to do for new GPy's purchased more recently was to add an external watchdog circuit using a Pic processor that cycles the +5V power to the GPy. To overcome lockups with the internal modem, the power must be cycled.

  • Hi, I have deployed roughly 150 of these. It has a learning cuve and some coding. The LTE connection thingy is not always a Pycom problem. First you need to have an operator that handles LPWA, ie LTE CAT-M1 or NB-IoT (different firmware) had several issues where the operators roam the CAT-M1 to 3G, and other related problems. Most important, your operator should have a separate APN for these kind of connections, if they have it, then you have found a good operator.

    In some cases the modem needs resetting, so open the Pycom firmware tool and make sure that when you update the device, the last setting where you select firmware version, make sure to tick all three additional boxes as well. That is a good starting point, please try that and see what it does.

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