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Unbricking Procedure for VOXL and VOXL Flight

Table of contents

  1. Overview
    1. Force VOXL into fastboot
    2. Reflashing System Image after Forcing the VOXL into Fastboot
  2. Prevent Flash Corruption (ie, Bricking)

Overview

The System Image flashing process requires the device to be in fastboot mode. The typical process uses adb to put the VOXL into fastboot mode over USB. If the device is bricked and one cannot get the VOXL into fastboot using USB, then you’d follow this process before running the install.sh script as described in the Flash System Image process.

The following VOXL add-on boards support the force fastboot mode switch:

Force VOXL into fastboot

To force the VOXL to boot into fastboot mode:

  • Power off the VOXL
  • Attach the USB Expander and Debug Add-On board
  • Ensure the FASTBOOT labeled switch is set to on
  • Ensure the EMERG BOOT labeled switch is set to off
  • Power on the VOXL
  • Immediately run the program to flash the system image
    • if the fastboot connection drops, repeat the procedure but immediately after power on, set the FASTBOOT switch to off

The VOXL will stay in fastboot mode for approximately 10 seconds. During this time, you can query for the device from a Linux system with the following command:

fastboot devices

You should see an output like:

a0259b4a    fastboot

NOTE: If the fastboot connection drops in the middle of the flashing process, try running the procedure above, but immediately after power on, toggle the FASTBOOT switch back to off

Reflashing System Image after Forcing the VOXL into Fastboot

To reflash the System Image, you need to run the install.sh program within 10 seconds of powering up the VOXL into fastboot mode. Forcing the VOXL into fastboot mode is covered in the previous section. Flashing the System Image using install.sh is covered in this section.

IF FLASHING STILL FAILS

If the flashing fails, boot the device up into fastboot mode as described above, immediately turn the fastboot switch off, and then immediately run the install.sh -f option to do a factory flash, which erases the data partition without prompting you.

Prevent Flash Corruption (ie, Bricking)

To prevent flash corruption, do not unplug power directly. Cleanly shut down services that are writing to flash before removing power.

One way to stop all services is to call poweroff before removing power from the VOXL or VOXL Flight. For example:

$ poweroff