org.freesmartphone.GSM.Network Signal Strength Signal

[Michael 'Mickey' Lauer]

Hi Thomas,


> The provider name is not something that changes a lot, but might
> change occationally, i.e. when you cross a border, or live somewhere
> nearby a border and get coverage from the other side.
>
> The signal strength on the other hand is a volatile information, that
> might change quite fast under certain situations (i.e. driving on a
> highway), which leads to a lot of messages.

I agree, however note that we don't send a NetworkStatusChange when the signal 
strength changes, we only send it once a +CREG comes in.

> I my opinion, it would make sense to decouple these signals, i.e:
>
> <signal name="SignalStrengthChanged">
>    <arg type="i" name="strength"/>
> </signal>
>
> and
>
> <signal name="NetworkStatusChanged">
>   <arg type="s" name="provider_name"/>
>   <arg type="s" name="status"/>
> </signal>

Btw., In the newest OTAPI this is a{sv}. Not that it does matter in that case.

> In that way, the standby screen application can filter for
> NetworkStatusChanged signals and will not be woken up for every signal
> strength update.

I agree, although I think this is overoptimized. Anyways, I can add this 
SignalStrengthChange for you, however this will be marked optional, since GSM 
07.07 has no unsolicited response code for signal strength anyways.

Modems which have facilities for that, can then use this signal.

> A kind of subscription mechanism would be ideal for the signal
> strength signal, so that the signal is only generated, when an
> application actually listens for it.
> (i.e. avoiding loosing CPU Cycles and context switches during full
> screen video playback...)
> Unfortunately, I do not know enough of DBUS introspection magic to
> understand if the phone daemon can learn if some applications are
> currently listening for a signal.

IIRC this is not possible (yet?) w/ dbus

> If introspection is a possible way to learn about listening processes,
> a similar signal could then be used for CellIDChanged. ophoned would
> even be in a position to switch on and off the generation of netreg
> unsolicited events from the modem.

Yeah, that would be nice. Could you make a proposal for that on the dbus list?

-- 
:M: