REQUEST FOR HELP: MC9090 stops passing traffic

I’m integrating a MC9090 (based on the SL9090) module on an ARM platform running Linux 3.4.42, Sierra QMI drivers S2.9N2.14+patches, and Sierra QMI SDK 03.00.02+patches. The patches applied are the ones previously posted to this forum.

Using connection manager (came with the SampleApps in the SDK), I can start a CDMA connection and get an IP address on the cellular device’s Linux network interface. I can then ping out to a host and get responses like expected.

At some point after this, traffic seems to slow to a crawl or completely stop. Pings timeout or an “unreachable” error is returned. The RX counters never incremented, and the TX counters either increment much slower than expected (1 packet every 2 minutes) or cease incrementing altogether. I can still query the device using the AT command interface.

The only thing that seems to fix the problem is power cycling the module. This, of course, causes an end-to-end reset of all components in the system.

Has anyone else experienced anything like this? Does anyone have a suggestion for what to do to debug this further?



what is the state of the module? does module goes to low power mode? You can use debugging tools like QXDM(windows) and dm capture on linux to take the logs and check what went wrong.


Thanks for the reply. The application code is not explicitly putting the module into LPM, so if it is, this would have to be something that the module is independently doing. I’ll try to capture the logs using dm capture (only have Linux) – thank you for the suggestion!