Sierra MC7355 working on pfSense with charge.co (USA paygo provider)
Charge.co is a new paygo provider, charging only $3/mo to keep the line active with $13/GB prices and no expiry on the data. This last piece is essential for the backup connectivity use-case - most paygo/prepay providers require you to use whatever data you purchased within 30 or 90 days.
Charge.co runs on Sprint, so I took a chance went on eBay and found a Sierra MC7355 (Sierra's model specifically designed for Sprint's LTE) for $25 after reading this topic: https://forum.pfsense.org/index.php?topic=96468.0
The basic info:
Hardware: pcengines apu1d, Sierra MC7355 (the Panasonic SKU - 1101888)
Phone number: *99#
Modem port: /dev/cuaU0.2 OR /dev/cuaU0.1 (see below)
I used the United States / Sprint / Sprint CDMA profile (unsure if it was necessary)
Note: charge.co shipped a micro-sim card so I had to purchase a sim adapter to fit it into the APU's sim slot
AT Commands guide for the modem: http://source.sierrawireless.com/resources/airprime/hardware_specs_user_guides/airprime–-em7355---product-technical-specification-and-customer-design-guidelines/
It took me nearly a whole day to get it to work, mostly because the card that I received was configured for Verizon. To check, use the AT commands:
cu -l /dev/cuaU0.1 # (may be cuaU0.2 instead - mine actually switched ports after firmware update. Use ~. to exit) AT OK AT!ENTERCND="A710" AT!GOBIIMPREF? ~.
With that command you can see the carrier it's configured for. The procedures for flashing when you're using a PCEngines board (no VGA) is a real pain, I documented that pretty extensively here: https://gist.github.com/mleinart/d14ec6fe5787017307f34c208602d804
The carriers Sierra provides (http://source.sierrawireless.com/resources/airprime/software/airprime-mc73xx-fw-package-build-4544/) are:
That is pretty awesome. I never heard of AT!GOBIIMPREF?
I used to switch using carriers firmwares found on the Sierra Source website.