Beaglebone Novatel USB760 Freeze

[wilcut...@gmail.com]

I've been running tests on a BBB using a Novatel USB760 cellular modem.  The test I am running is rather simple-- just pinging the modem for it's RSSI settings so that I can modify some BB led's to show reception levels [4 'bars'].

After some time the modem freezes and stops communicating.  Breaking the script and restarting doesn't help-- all communication to the USB stick is dead and a reboot is required.  I'm doubtful it is the USB stick itself since there's been a lot of internet chatter of issues with the USB drivers on Linux [but I could be wrong].

My boot command line:

cmdline=console=ttyO0,115200n8 root=/dev/mmcblk0p1 quiet loglevel=3 usbcore.autosuspend=-1

I am using:

4.1.15-ti-rt-r48

I added "autosuspend" as a suggestion from another site [and have yet to test it].

The last test I ran [without autosuspend] got me to 15,577 seconds (4 hours) and an iteration count of 70,741.  At that point, a lock up occurred.  lsusb still showed the USB stick was present.

Anyone have any suggestions?

Here's my script:

#!/bin/bash

leddir="/sys/class/gpio"
cmdport="/dev/ttyUSB0"

# Specify which GPIOs belong to which LEDs.

led_1_gpio=46
led_2_gpio=27
led_3_gpio=65
led_4_gpio=22

# Locale of GPIO pins in fsys

led_1_bar="$leddir/gpio$led_1_gpio"
led_2_bar="$leddir/gpio$led_2_gpio"
led_3_bar="$leddir/gpio$led_3_gpio"
led_4_bar="$leddir/gpio$led_4_gpio"

function traperr {
        while read -t 0 var < $cmdport; do continue; done
        echo "err"
}
trap traperr ERR

function setup_gpios {
        # If GPIOs are not already exported, export them here.
        # Set their directions to output.

        if [ ! -e $led_1_bar ]; then
                echo $led_1_gpio > $leddir/export
                echo out > $led_1_bar/direction
        fi

        if [ ! -e $led_2_bar ]; then
                echo $led_2_gpio > $leddir/export
                echo out > $led_2_bar/direction
        fi

        if [ ! -e $led_3_bar ]; then
                echo $led_3_gpio > $leddir/export
                echo out > $led_3_bar/direction
        fi

        if [ ! -e $led_4_bar ]; then
                echo $led_4_gpio > $leddir/export
                echo out > $led_4_bar/direction
        fi
}

function flush_modem {
        echo "Flushing buffers..."
        input="$cmdport"
        echo -e -n "\r"
        while read -t 0 var < $cmdport; do continue; done
}

function get_attention {
        input="$cmdport"

        echo "Detecting modem..."

        # Get modem attention

        echo -e -n "\n\n"
        tries=1

        until [[ "$line" == "OK" && "$tries" -lt 10 ]]
        do
                echo -e -n "Try #$tries\r"
                echo -e -n "\nAT\n" > $cmdport
                read -r -t 2 line
                tries=$((tries+1))
        done < "$input"

        echo -e "\n"

        if [ "$tries" -eq 10 ]; then
            echo "Could not establish communication to modem, giving up."
            exit 1
        fi
}

function query_modem {

        input="$cmdport"

        # Communicate to the USB Wireless adaptor modem.
        # Query for RSSI - Receive Signal Strength Indicator

        echo -e -n "\nAT\$NWRSSI\n" > $cmdport

        # Command USB for RSSI info

        while read -r -t 2 line; do
                if [[ -z $line ]]; then
                        continue;
               elif [[ "$line" == "OK" ]]; then
                        break;
                else
                        rssi=${line#*=}
                        echo "$counter>$rssi"
                        counter=$((counter+1))

                        # Change LEDS - Only channel 1 is used on Onyxx
                        # 110+     : No leds (bad quality)
                        # 94 - 109 : 1 led (marginal)
                        # 85 - 93  : 2 leds (okay)
                        # 75 - 84  : 3 leds (good)
                        # 0 - 74   : 4 leds (excellent)

                        rssi=$(echo $rssi | tr -d "[:alpha:][:blank:][:space:][:punct:]")

                        if [[ $rssi -ge 110 ]]; then
                                echo 0 > $led_1_bar/value
                                echo 0 > $led_2_bar/value
                                echo 0 > $led_3_bar/value
                                echo 0 > $led_4_bar/value
                        elif [[ $rssi -ge 94 ]]; then
                                echo 0 > $led_1_bar/value
                                echo 0 > $led_2_bar/value
                                echo 0 > $led_3_bar/value
                                echo 1 > $led_4_bar/value
                        elif [[ $rssi -ge 85 ]]; then
                                echo 0 > $led_1_bar/value
                                echo 0 > $led_2_bar/value
                                echo 1 > $led_3_bar/value
                                echo 1 > $led_4_bar/value
                        elif [[ $rssi -ge 75 ]]; then
                                echo 0 > $led_1_bar/value
                                echo 1 > $led_2_bar/value
                                echo 1 > $led_3_bar/value
                                echo 1 > $led_4_bar/value
                        elif [[ $rssi -gt 0 ]]; then
                                echo 1 > $led_1_bar/value
                                echo 1 > $led_2_bar/value
                                echo 1 > $led_3_bar/value
                                echo 1 > $led_4_bar/value
                        fi;
                fi;
        done < "$input"
}

# The program main()

echo "USB760 RSSI Bar Application"
setup_gpios
flush_modem
get_attention

counter=1
while true; do
    sleep 0.1          # Allow USB to catch it's breath
    query_modem
done

[sreenuy...@gmail.com]

http://sreenu.searchbuk.com/