Auto connect of Telit LE910 after reboot

Cellular Modules Telit LE910C1/C4 LTE Module
1

My HAT and Telit LE910C1 runs OK after the installation and connection works well.
How can I automate the step of giving the AT-command for the boot to avoid manually activating the connection via AT commands?
AT#ECM=1,0,"","",0

Currently I give it with the minicom, but it MUST be automated.

Regards,
-severi

2

I have the same question. This is kind of a dealbreaker for managing the device remotely.

3

Hi,
have you figured out a way of solving it?

4

I just had to figure this out myself and here is what I came up with that seems to be working well.

first, make sure that modemmanager is not installed because otherwise it tries to take over:

sudo apt-get remove modemmanager

Next make the serial port writable by non-root users (optional but otherwise use root crontab – untested)

chmod o+rw /dev/ttyUSB2

Next make a shell script to do the monitoring and reconnecting: sudo nano ~/net_fix.sh

#!/usr/bin/bash

ping -I wwan0 -c 1 8.8.8.8 > /dev/null
ping_result_1=$?
sleep 1
ping -I wwan0 -c 1 8.8.4.4 > /dev/null
ping_result_2=$?

if [ $ping_result_1 -ne 0 ] && [ $ping_result_2 -ne 0 ]; then
	stty -F /dev/ttyUSB2 115200 raw -echo -echoe -echok -echoctl -echoke 2> /dev/null
	echo -ne '\rAT#REBOOT\r' > /dev/ttyUSB2
	sleep 50 # 25 is the minimum. Safety factor of 2
	stty -F /dev/ttyUSB2 115200 raw -echo -echoe -echok -echoctl -echoke 2> /dev/null
	echo -ne '\rAT#ECM=1,0,"","",0\r' > /dev/ttyUSB2
fi

make the script executable:

sudo chmod +x ~/net_fix.sh

make a cron job to run the script every two minutes: crontab -e

*/2 * * * * /home/pi/net_fix.sh

That will force the modem to reboot and reconnect every two minutes if it cannot ping either 8.8.8.8 or 8.8.4.4 (the google dns servers)

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