On 03/24/2014 03:45 PM, Yevhen Kyriukha wrote:
I use 3G modems connected to unattended terminals for a long time.
I use ofono for managing 2G connections.
All this time I'm suffering from modem hangs: during establishing 2G
connection modem may hang, i.e. it stops reacting on AT commands to
I'd tested a lot of modems of different brands before selecting one.
And I have to say that *every* model has such issue.
Most commonly this is a sign that the AT command responses are not
formatted properly. Are you running the v250 parser by any chance? The
permissive parser is more forgiving.
So I created a workaround for this (patched ofono):
When I send AT command I start a timer that fires when no response is
received during some timeout. So if timeout is reached I send
command that makes modem reset.
After that modem can be usable again.
If the modem responds to AT commands, then the likely cause is something
else. Most 'real' hardware deals with true modem firmware crashes
I was surprised that ofono doesn't have such functionality.
So I think ofono should have some sort of mechanism to reset the modem
if it stops responding.
What do you think?
Share the AT command logs of when this happens, maybe there is a simpler