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  • Cool, thanks for that info. Yeah, I have found the GPRSbee to be pretty good; we have four of them that have been operating for over a year now and they all just keep trucking along.

    It’s strange, I do also have an XBee3 (XB3M1, XB3-C-A2-UT-001 RevH) but have never been able to get it to power up or respond in any way on the Mayfly. I have SJ13…[Read more]

  • Thank you Sara. Unfortunately those changes didn’t do the trick. I may have to fall back to using some GPRSbees for this project and hope that T-Mobile doesn’t shut down their 2G towers too soon 🙂

  • Sara, this is really amazing support. Thank you very much for your contributions to the community.

    Unfortunately, problems persist. As far as I can tell, switching to synchronous close did not improve the situation. I’m attaching another log, this time with TINY_GSM_DEBUG enabled. We are still sometimes getting +CME ERROR: Operation not allowed[Read more]

  • Thanks Sara. Some more info for you. First, the CGMR and GMR commands both result in the response ERROR, as you can see in the output below.

    Additionally, it sometimes seems to struggle getting a connection to NIST, also as in the example below. It took two tries before it finally connected, and this seems to be commonb. Note also the funkiness…[Read more]

  • Thank you Sara.

    Inching closer. Prior to switching to the modemLast branch I tried something similar to what @acgold suggested. I added the following lines:

        if (modemVccPin >= 0)
            pinMode(modemSleepRqPin, OUTPUT);
            digitalWrite(modemSleepRqPin, HIGH);

    to my file, just after greenredflash();. This allowed the…[Read more]

  • Hi Sara,

    Thanks for the reply. Unfortunately, that didn’t fix it. Bummer! This issue seems reminiscent of the last post by acgold on that GH issue. This is what the relevant lines of my setup look like now, but still no dice. Anything else?

            Serial.println(F("Delaying 500 after powerup"));…

    [Read more]

  • After I successfully got the uBee U201 to work for my application, Sodaq stopped producing that model and now only offers one based on the R410. So I’m working on getting the uBee R410 to work.

    Scouring through this GitHub issue got me very close but can’t quite get it to work. I’m using hologram, ModularSensors 0.23.16 and a code based on…[Read more]

  • I noticed both the LTE Bee Adapter and the Mayfly Data Logger Starter Kit are unavailable on Amazon. Are there plans to replenish stock in the near future? Thanks.

  • When powering on the MayFly running a script with a Logger object, 10 samples are recorded at 2 minute intervals, regardless of what the value of loggingIntervalMinutes is. After these 10 samples, the logger reverts to loggingIntervalMinutes.

    I have additionally found that every ~256 measurements, (in my case, where I’m sampling at 15 minute…[Read more]

  • Thanks Sara. The modem responds with an “OK” to the “+++” in setup() but once it’s in the loop it does not respond to anything I type in the serial monitor (AT commands, +++, etc). That’s the purpose of the StreamDebugger, right?

  • Well, I have regressed even further. Now I can’t even get the modem to turn on. I confirm ~4.2V between pins 10 and 1 on the Xbee, so it is definitely getting power (and from the LiPo to boot) but it is no longer responding to the first initialization in e.g. logging_to_EnviroDIY.ino. Unforunately I don’t have any development board other than the…[Read more]

  • Thank you Shannon.

    OK, I cut the trace and confirmed no continuity between BEE_Vcc and 3v3 at SJ13. Then I made a solder bridge between BEE_Vcc and LIPO. I have ~4.1V between GND and LIPO/BEE_Vcc.

    The modem powers up and is evidently powered by the battery now but I still end up with the NO RESPONSE messages…

  • OK, looking at the GitHub issue, it looks like I may need to Solder SJ13 after all…?

  • I recently successfully set up a MayFly with GPRSbee radio. It works great.

    I’m trying to get a second MayFly working with the Digi XBee3 LTE-M radio. This is on hologram, using a brand-new SIM card, which I understand should be possible. I’m not sure if I’m getting to that point, since even initializing the radio doesn’t seem to work 100%. I…[Read more]

  • Sara, thanks for your thoughtful and complete response. I’ve been reading a lot of threads, and hadn’t realized the issue with Digi XBees was restricted to Hologram SIM cards. I’m using a Hologram card for now, but am not committed to it.

    Is this an accurate summary of the present situation for XBee modules and MayFly?

    Sodaq GPRSBee: 2G only,…[Read more]

  • What’s the current (Oct 2018), best-supported cellular XBee radio for use with a MayFly? It would be nice to have a US-based supplier and it seems the GPRSBee is available only from Sodaq in the Netherlands. The newer 3G and LTE XBee radios from Digi are more easily available through Mouser and Digi-Key but may or may not be fully supported on the…[Read more]

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