SD card autorun script

The system will automatically run autorun file of the sd card's first part if the sd card is mounted. The start-up sequence is /etc/init.d/autorun -> /root/autorun.sh -> /root/sd_daemon.sh -> /tmp/run/mountd/mmcblk0p1/autorun. When a sd card is inserted, its first part will be mounted at /tmp/run/mountd/mmcblk0p1/. If your sd card is not automatically mounted, try to format it with sd card formatter.

To do a factory reset

We can add firstboot to sd card's autorun to perform a factory reset. For example, copy the following script and save it to the sd card's root directory with filename autorun.

#!/bin/sh

if [ ! -f /tmp/run/mountd/mmcblk0p1/reset_once ]; then
    firstboot
    touch /tmp/run/mountd/mmcblk0p1/reset_once    # add a flag file to run `firstboot` once
    reboot -f
fi

To recover ATmega32U4's bootloader

#!/bin/sh

if [ ! -f /tmp/run/mountd/mmcblk0p1/done ]; then
    /etc/init.d/mopidy stop  # stop mopidy if it's running, mopidy-hallo plugin will use SPI
    /etc/init.d/alexa stop      # stop alexa if it's running
    mt7688_pinmux set ephy gpio
    cd /etc/arduino
    avrdude -c linuxgpio -p m32u4 -e -U lfuse:w:0xFF:m -U hfuse:w:0xD8:m -U efuse:w:0xCB:m  -U flash:w:Caterina-ReSpeaker.hex -u
    touch /tmp/run/mountd/mmcblk0p1/done
fi