I’m confused about which modem firmware I should be using with the WP7702 (R12). I’m using Hologram SIM cards. In my area in the United States, these Hologram cards typically connect to AT&T on LTE or T-Mobile on 2G.
Hologram isn’t a carrier – so which carrier firmware should I pick? I’m using the modem firmware SPK files on this page: https://source.sierrawireless.com/resources/airprime/software/wp77xx/wp77xx-firmware-latest-release-components/#sthash.74J2zVN6.dpbs
Sierra firmware
- Connects fine to AT&T LTE and T-Mobile 2G
- On LTE,
pmtool shutdown
prints “Initiated shutdown of MDM” and does nothing, looks like it’s enabling PSM so I have to doAT+CPSMS=0
afterward, then it will shut down. On 2G it works without the CPSMS stuff. -
AT!POWERMODE=3
works and bypasses the CPSMS problem on LTE
AT&T firmware
- Connects fine to AT&T LTE and T-Mobile 2G
- On LTE,
pmtool shutdown
prints “Initiated shutdown of MDM” and does nothing, looks like it’s enabling PSM so I have to doAT+CPSMS=0
afterward, then it will shut down. On 2G it works without the CPSMS stuff. -
AT!POWERMODE=3
returns ERROR.
Verizon firmware
- Connects fine to T-Mobile 2G. Doesn’t seem to work with LTE, not even Verizon’s network. This might be Hologram’s fault.
-
pmtool shutdown
seems to work, even without needing to disable PSM. Probably because it’s not connected on LTE. -
AT!POWERMODE=3
returns ERROR.
Generic PTCRB firmware
- Doesn’t connect to any networks. Neither LTE nor GSM.
-
pmtool shutdown
seems to work, even without needing to disable PSM. Probably because it’s not connected on LTE. -
AT!POWERMODE=3
returns ERROR.
Generic GCF firmware
- Doesn’t connect to any networks. Neither LTE nor GSM.
-
pmtool shutdown
seems to work, even without needing to disable PSM. Probably because it’s not connected on LTE. - AT!POWERMODE=3 works.
In general, it looks like I’m not allowed to use AT!POWERMODE at all on most firmwares, with the exception of Sierra’s firmware and the GCF firmware. In the firmwares where I’m not allowed to use it, even AT!POWERMODE?
returns ERROR. It looks like the “auto PSM enabling” preventing ULPM until I do AT+CPSMS=0 is dependent on whether I’m connected on an LTE network or not. On GSM it doesn’t happen but on LTE it does.
Logically based on these results, it seems like I have to pick either the Sierra firmware or the AT&T firmware. Is the Sierra firmware only meant for Sierra SIMs? Is it even okay for me to use that firmware with a Hologram SIM? It works…but am I technically doing something wrong by using it? What about shipping internationally? Would I need to switch to GCF firmware for international units? Is it normal that I can’t seem to use the generic firmware (GCF/PTCRB) properly in the USA?
Any insight would be much appreciated. My head feels like it’s spinning after doing all these tests.