Boron LTE- support


Re: Old hologram SIM, I was going to mention that if you see +CEREG: 2,3 repeatedly you are being rejected by the network and likely the SIM is not activated. It seems like your SIM is still active though (since you can use it on other devices), so possibly you are being rejected for too many connection attempts recently with that IMEI+ICCID combo (like a temp ban). Perhaps give it 24 hours to cool down and try again briefly to see if it has resolved itself.

I’d be interested to know what the AT+CGDCONT= command being used on the Arduino MKR NB 1500 is as well as there might be some subtle difference here that makes it work with that SIM specifically.


Thanks, BDub! That really helps to know – and makes sense after watching endless debug output.

Reuben @Hologram has a compatible explanation – the SIM may have had data written to its blacklist at some point.

I’ll try to get you the AT+CGDCONT= value as soon as I can get the NB 1500 back online. Right now, none of my formerly fine-working Hologram SIM’s will connect with the Arduino NB1500. I let them “rest” all weekend, too – completely powered down.


The Cat-M1 world is strange. Could not connect with my Hologram SIM’s last night at all, after days of being powered down. Tried again this morning, same thing. After 30 minutes powered down, connected with no issue.

There is no AT+CGDCONT= command explicitly called, unless there is something hidden in the SIM that I and the debug mode are not seeing.

Connected as:
+CEREG: 0,5


You can try issuing a AT+CGDCONT?\r\n to see what the current setting is. I’m not familiar with how the Arduino NB1500 makes it’s connection to the tower… but I imagine it’s similar to how we do it.


Also you might want to take hologram’s own advice on how to clear the FPLMN list on their SIM:


Hey, BDub,

Hugely useful information – thank you!

CGDCONT status below.

YES! There was indeed information written to the Forbidden Zone of Forbidden Providers. Cleared.

Connected just fine today, then checked:
+CGDCONT: 1,“IP”,“hologram”,“”,0,0,0,0

Check the Blacklist:

Clear the Blacklist:
+CRSM: 144,0,""

Verify empty Blacklist:

Definitely going to be reading up on SIM technology / settings. Thanks for pointing me in the right direction.

Also, put me down on this wishlist: “AT command passthrough mode” app for Electron and Boron. Really makes this type of work easy and fast after the Arduino “SARA pass-through” sketch is loaded. especially for those of us who grew up on “speaking Hayes” since way too long ago. :slight_smile:

UPDATE: Mar 7, AM: All SIM’s working well today. Lesson learned: Don’t willy-nilly switch SIM’s among devices; lest the Cellular Tower Gods grow angry.


All working great here in New Zealand. Spark (our telco) has just rolled out the IoT comms and after following the 3rd party sim guide The Boron LTE connects and works great. Looking forward to a better coverage as the existing 3G network range was not great.


Michael, this is fantastic!

Question, after getting the Boron on the network with the Hologram SIM, were you able to send/receive SMS messages? If so, can you share the code?


I’m really curious if anyone in this thread knows what interactions the Boron is having with the Particle Cloud after it’s configured with the Hologram SIM?

It seems a little silly to pay BOTH Hologram AND Particle for cellular access. And Particle charges 3 per month per device when you go over 100 devices. Has any one in this thread disabled access to Particle Cloud so that fee wouldn’t be occurring?


You can just deactivate the particle-SIM in the console if you don’t want to use it and use your third-party SIM instead, that works fine. Particle doesn’t charge you for deactivated SIMs.


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