modem has to stay in registered state for a second before it can connect

Arkadiusz Drabczyk arkadiusz at
Mon Nov 7 22:30:34 UTC 2022

On Mon, Nov 07, 2022 at 04:02:29PM +0100, Aleksander Morgado wrote:
> A very similar issue was fixed for Qualcomm modems using QMI in the
> following merge request:
> The problem solved there was that the connection attempt was started
> before the modem was fully registered properly in the PS domain. In
> QMI modems we improved the detection of the PS domain registration to
> use the DSD service, and only if the DSD service reports a valid
> access technology we consider ourselves registered in PS. Those
> changes don't introduce any arbitrary delay, instead we rely on the
> modem notifying the correct state via updates. But the effect is the
> same really, we're waiting just a little bit more between us getting
> registered and starting a new connection attempt. Not saying the issue
> is the same one, but it looked similar.
> In your case, we rely on +CEREG to know whether we're registered or
> not in EPS, and if we are, we go on with the connection attempt. I
> don't know if we're missing something else to check before starting
> the connection attempt. Would you be able to contact the manufacturer
> directly (e.g. via support or forum) to ask about this?

Sure, I'll try to contact the manufacturer, I also know that there are
some users who work for Thales and are active on so maybe
I'll create an issue to attract their attention :) Thanks for help.

Arkadiusz Drabczyk <arkadiusz at>

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