MC7710 "forgetting" RAT

[Bjørn Mork]

"Martin Anderseck" <Martin.Anderseck at ni.com> writes:

> Hi,
>
> I did some more testing and it looks like I found a systematic behaviour: 
> - I boot the system and check the RAT value using AT commands, it looks 
> okay.
> - I start ModemManager in one terminal and wait until the modem is 
> available
> - I use a second terminal to perform a mmcli --simple-connect
>   => Exactly here it hangs, it won't connect.
>
> If I quit ModemManager then and check the RAT value on the AT port again I 
> get the invalid value. 
>
> As you've said that you don't set anything related to the RAT within 
> simple-connect I can only guess that the firmware doesn't understand 
> something it receives in that process, right?

It is probably worth noting that the AT!SELRAT command affects the same
firmware settings as QMI, but does a combination of "technology" and
"system-selection" preferences.

So if MM touches any QMI setting, then this will be directly reflected
in the AT command.  For example:

bjorn at nemi:~$ qmicli -d /dev/cdc-wdm0   --nas-get-system-selection-preference 
[/dev/cdc-wdm0] Successfully got system selection preference
        Emergency mode: 'no'
        Mode preference: 'lte'
        Band preference: 'gsm-dcs-1800, gsm-900-extended, gsm-900-primary, gsm-pcs-1900, wcdma-2100, wcdma-900'
        LTE band preference: '1, 3, 7, 8, 20'
        Roaming preference: 'any'
        Network selection preference: 'automatic'
        Service domain preference: 'ps-only'
        Service selection preference: 'automatic'

at!selrat?
!SELRAT: 06, LTE Only


OK


bjorn at nemi:~$ qmicli -d /dev/cdc-wdm0 --nas-set-system-selection-preference='gsm|umts|lte'
[/dev/cdc-wdm0] System selection preference set successfully; replug your device.
bjorn at nemi:~$ qmicli -d /dev/cdc-wdm0   --nas-get-system-selection-preference 
[/dev/cdc-wdm0] Successfully got system selection preference
        Emergency mode: 'no'
        Mode preference: 'gsm, umts, lte'
        Band preference: 'gsm-dcs-1800, gsm-900-extended, gsm-900-primary, gsm-pcs-1900, wcdma-2100, wcdma-900'
        LTE band preference: '1, 3, 7, 8, 20'
        Roaming preference: 'any'
        Network selection preference: 'automatic'
        Service domain preference: 'ps-only'
        Service selection preference: 'automatic'


at!selrat?
!SELRAT: 07, GSM, UMTS, LTE


OK



Bjørn