We have a product we’ve developed in the UK that use the HL7692 modem, which we are very happy with.
Our partners in the US want to use our product, so initially together we selected the HL7618RD for Verizon and HL7688 for AT&T.
The HL7688 for AT&T works as expected (as per what we’re used to with the HL7692), however we’ve been having huge issues getting the HL7618RD to connect.
The HL7618RD, seems to sit in CEREG, CGREG, CREG state 0, occasionally going to state 2 to indicate that it is searching for a network to join then immediately going back to state 0 - Not Registered Not searching.
During this time the device does receive +XCESQI signal strength indicators.
We’ve left the device for a couple of hours, and seemingly it does eventually connect but then is unable to send and receive SMS. Our partners in America told us that Verizon is a bit peculiar when it comes to letting devices on their network and we found out that the HL7618RD isn’t on Verizons approved list of modems.
We then bought a HL7588 to try, as this modem is on Verizons list of approved modem, and are still having issues.
This modem does connect to the Verizon network - CEREG and CGREG are reporting state 1 (Registered), however CREG is reporting state 3 (Registration Denied). COPS was reporting that it was registered on Verizon and state 7 (LTE), and the device was receiving +XCESQI signal strength indicators
We’re unable to send SMS from the device, or receive SMS - no CMTI indications were received even though the device is setup to receive these. Nor were our partners able to call the device, it went straight to voicemail.
We wondered if our partner was using a Data only Verizon SIM, but i’ve been informed that they’ve tried the SIM in a phone and were able to SMS & call.
I check to see if the modem had a Message Centre set and had the following response
I’m unsure of the PDP contexts mentioned in the AT Command Specification notes, but this was the response to a AT+CGACT? - which I think looks ok?
I would appreciate any assistance with this, whilst we can potentially move forward with the AT&T solution, we would like to offer a Verizon option also, and i’m a little bit stuck as to where to go from here.