It's connected to the auxiliary lines on one of the USB-C connectors. Tickle it the right way and it will happily overwrite the boot firmware -- so long as the image you give it is signed by Google. It will do this without any intrusion into the chassis. Very convenient for, say, airport security inspectors, who would arouse suspicion if they took the time to open the case. Plug in the magic USB dongle, press the power button, the deed is done.
There were a precious few aarch64 chromebook models without it, but they've all been discontinued.
http://www.loper-os.org/?p=2433
It's connected to the auxiliary lines on one of the USB-C connectors. Tickle it the right way and it will happily overwrite the boot firmware -- so long as the image you give it is signed by Google. It will do this without any intrusion into the chassis. Very convenient for, say, airport security inspectors, who would arouse suspicion if they took the time to open the case. Plug in the magic USB dongle, press the power button, the deed is done.
There were a precious few aarch64 chromebook models without it, but they've all been discontinued.