It seems that not matter what method I use, the modem doesn’t initialize after booting up. I had previously created a service and script to initialize it. That worked a few times but then it stopped working. I tried using a cron job to run the script and that didn’t work for long. I went in and made sure I saved AT#ECM=1,0 by also running AT&W (to save current config) and it works like a charm when I do it manually, but it won’t save or run the scripts. I’m at a loss now, out of ideas.
Hello @jonathonsantosa,
Thank you for sharing the details.
This behavior is expected with Telit modules. The command:
AT#ECM=1,0
(which enables ECM mode and brings up the wwan0 interface) is not persistent across reboots, even if you run AT&W. This means it must be executed again after every boot.
The issue you are experiencing with systemd or cron is most likely due to a timing (race condition). The script runs before the modem is fully initialized, so the AT port (e.g., /dev/ttyUSB2) is not ready yet.
To resolve this, we recommend:
- Adding a delay in your startup script (e.g., sleep 20–30 seconds) before sending AT#ECM=1,0
- Ensuring the script runs only after the modem interface is available
- Verifying that the correct ttyUSB port is used
In summary, the command must be re-run after each reboot, and your script should wait until the modem is fully ready before executing it.