Update Bootloader

Trellises now come with a locked (protected) bootloader so you do not need to perform this step if you have an ADABOX Trellis!

On the very first batch of Neo Trellis M4 Express boards, the factory bootloader was not protected against accidental overwriting. Normally, the bootloader is unlikely to be damaged, but certain buggy programs and certain development environments might overwrite the bootloader. If you have one of these boards, we recommend you update the bootloader, which will protect it against overwriting as part of the updating process.

To see if your board needs updating, double-click the reset button, and look at the INFO_UF2.TXT file in TRELM4BOOT. If the bootloader version listed is earlier than "UF2 Bootloader v2.0.0-adafruit.7", you may want to update.

Download the bootloader updater below. Double-click the reset button and wait for the TRELM4BOOT drive to appear. Then drag or copy the updaterTRELM4BOOT. Wait for TRELM4BOOT to reappear. Your bootloader is now protected against overwriting.

After updating, you'll need to reload CircuitPython or whatever other program was loaded on the board. Your CIRCUITPY drive is not affected by the updater on NeoTrellis M4 Express, because it's on a separate SPI flash chip.

Updating the bootloader means you will need to reinstall any older program/CircuitPython via https://learn.adafruit.com/adafruit-neotrellis-m4/circuitpython
This guide was first published on Oct 31, 2018. It was last updated on Oct 31, 2018. This page (Update Bootloader) was last updated on Mar 28, 2020.