Executing AT commands from OpenWRT webinterface
I wanted a quick way of executing AT commands to my 4G modem in my OpenWRT router and reading the results. To do this I installed
root@OpenWrt:~# opkg update
root@OpenWrt:~# opkg install coreutils-stty
Then I created this script, execAT.sh, and added to OpenWRT:
#!/bin/sh
# First parameter: Device
# Second parameter: AT command to execute
# Example sh execAT.sh ttyUSB2 at!gstatus?
# set up modem device to translate outgoing \n into \r\n
stty -F /dev/$1 9600 -echo igncr icanon onlcr
# Open modem for reading and writing
exec 5</dev/$1
exec 6>/dev/$1
echo $2 >&6
# Remove the echo and the blank line
read <&5
read <&5
FLAG="GO"
ZeroCounter=0
#READING FROM SERIAL
while [ "${FLAG}" == "GO" ]; do
read -t 1 RESPONSE <&5
echo -e "$RESPONSE"
if [ "${#RESPONSE}" -eq 0 ];
then
ZeroCounter=$((ZeroCounter+1))
else
ZeroCounter=0 # Reset counter
fi
# If we get and OK then quit; or we we get an empty response 3 times in a row
if [ "${RESPONSE}" == "OK" ] || [ "${ZeroCounter}" == "3" ];
then
FLAG="EXIT"
fi
done
# Close the connections
exec 5<&-
exec 6>&-
I tested it from the commandline first:
root@OpenWrt:~# chmod +x execAT.sh
root@OpenWrt:~# sh execAT.sh ttyUSB2 ati
Model: EM7455
Revision: SWI9X30C_02.32.11.00 r8042 CARMD-EV-FRMWR2 2019/05/15 21:52:20
MEID: 35399007042761
IMEI: 353990070427617
IMEI SV: 19
FSN: LF611310230210
+GCAP: +CGSM
OK
Then I add a plugin to execute shell scripts from the user interface and read the results:
root@OpenWrt:~# opkg install luci-app-commands
And then I just configure the command in OpewWRT and can execute it directly from the interface and read the response:
