qtMoko getting bad Network Time

Paul Wise pabs3 at bonedaddy.net
Wed Jan 7 04:08:21 CET 2015

On Wed, Jan 7, 2015 at 8:51 AM, Jorge wrote:

> Thanks for the confirmation. A question, can you confirm that the session
> excerpt is the one of interest, and it actually says the provider is giving
> the +34 time zone? That would be strange, being the biggest celular provider
> around here. With my Nokia dumbphone I've never seen something like that
> (OTOH, time updatting hasn't worked for me at all last time I needed it).

America/Montevideo seems to be two hours behind UTC.

The log confirms that QtMoko is definitely looking for the GMT-34 timezone.

Looking at the QtMoko source code, +CTZV is an "Unsolicited result
code for time zone change events".


Your operator's CTZV value is 136.

The code handling the +CTZV message is here:


That code produces 34 hours in front of UTC for your operator's CTZV value.

There are two other FLOSS implementations of CTZV handling that I know
of, FSO and oFono:


Looking at the FSO code, it produces 8 hours behind UTC for your
operator's CTZV value.


Looking at the oFono code, it produces 34 hours in front of UTC for
your operator's CTZV value.


I then tried to find a reference for how to do this correctly, since
none of the FLOSS implementations I can find produce a result that
matches TZ=America/Montevideo.

The closest I could find is a reference to the value being an offset
from Universal Time in units of 15 minutes.

Not sure what the right answer is here, I think you will need to do
more testing with the same SIM card in a variety of phones from you
and your friends and record the resulting timezone offsets. If you can
also record the CTZV value (some phones have debug info available)
that would be helpful too, in case different phones get different
values or use another command. Start by setting the timezone UTC, then
turn on automatic timezone info and then find out what the resulting
timezone offset is. If any of them then get the correct timezone
you'll need to figure out how.


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