LTE attach settings - CFUN

[Aleksander Morgado]

Hey

> > > > > > I will have to run the following sequence:
> > > > > > -        go in AT+CFUN=4 (airplane mode with SIM connected). This is
> > > > > > necessary because the CID might be locked or not taken into account
> > > > > > immediately (in case there is an attach attempt ongoing).
> > > > > > -        set AT+CGDCONT for the right CID (normally 1)
> > > > > > -        set AT^SGAUTH for the same CID
> > > > > > -        go back to AT+CFUN=1.
> > > > > >
> > >
> > > I am implementing this sequence, and will submit soon (I hope), but I
> > > am stepping into a problem with CFUN:
> > >
> > > ModemManager[2541]: <debug> [1595452432.501830] [modem0/ttyACM0/at]
> > > --> 'AT+CFUN=1<CR>'
> > > ModemManager[2541]: <debug> [1595452432.533882] [modem0/ttyACM0/at]
> > > <-- '<CR><LF>OK<CR><LF><CR><LF>^SYSSTART<CR><LF>'
> > > ModemManager[2541]: <debug> [1595452452.512543] [modem0] (cinterion)
> > > error in step = 5
> >
> > Maybe you should add a regex to ignore the ^SYSSTART URC.
>
> not sure how to do it. Any examples I can look at?

The huawei plugin has a lot of "ignore regex" entries, those are good examples.

> I have also noticed that it could be a known issue, because in
> src/mm-broadband-modem.c: modem_power_up(), the error is not checked,
> and the command
>         mm_base_modem_at_command (MM_BASE_MODEM (self),
>                                   "+CFUN=1",
>                                   5,
>                                   FALSE,
>                                   NULL,
>                                   NULL);
> takes 5 seconds  and then continues. It works faster if the modem is
> already in cfun=1, because then there is no urc, only ok, but takes 5
> seconds (the timeout) when changing from another mode.
>

That code is the generic one, not actually Cinterion specific. The
reason for not handling CFUN errors is given in the finish():

    /* By default, errors in the power up command are ignored.
     * Plugins wanting to treat power up errors should subclass the power up
     * handling. */


-- 
Aleksander
https://aleksander.es