FreeCalypso update: progress with DSP patches and voice calls

[Das Signal]

Hi Mychaela,

I redid the tests just to be sure; recompiled and reflashed gsm-fw,
then had the GTA02 and another phone register and made a call to the
GTA02 handset. I can confirm the voice was fine. I'm using a version of
gsm-fw from 2015-10-19 "static DSP patch download enabled by default".
Please note I don't issue AT commands by hand, instead I simply launch
the qt-moko GUI.

Perhaps the issue you're seeing is not due to the codec, but another
quirk of the DSP. For instance, OpenBTS does not enable encryption by
default (it only supports A5/3 anyway, which is too recent for Calypso).
Although I don't know the internals of GSM that well, I remember other
features of commercial networks, such as channel hopping, are not
present either in OpenBTS.

--DS