This article covers flashing the full disk image that the Aaeon tablets use in the Douro. It can be used as a full replacement drive, with no performance impact.
You'll need a 32GB USB 3.0 drive with a compact profile. We recommend this Samsung drive.
The lamassu-machine version contained in the image is v3.5.1 (next-gen).
Identify your tablet model
You can determine which model your tablet is by its USB ports.
The ACP-1103 has all black USB 2.0 ports, the ACP-1104 has one blue USB 3.0 port next to its power button.
Download the image
Download the Lamassu drive image specific to your tablet. The images are around 3 GB.
Formatting the drive
With your computer's disk management utility, format the drive, specifying an MBR partition table if given the option.
Flashing the drive
Disconnect all external drives and devices connected to your computer, except for the destination USB drive.
Download and install Etcher (available for Linux, Mac, and Windows): https://etcher.io/
In Etcher, select the image file downloaded earlier, then select the destination USB drive and click flash.
WARNING: Be very careful when selecting the destination drive, ensuring that you correctly point it to the destination USB drive and not that of your system's drive or any other devices you have connected, as the command will result in full data loss to the destination.
Booting from the drive
Once complete, eject the USB drive from your computer and follow this article in order to boot the Douro from it: Booting from a system flash drive