The Industrial Raspberry Pi Forum

Hello,
Can I boot my revpi core 3+ from USB device?

You mean attach a USB stick and use it as root filesystem?

That might work, though we've never tested it. The /boot partition on the eMMC contains the kernel. And the drivers for the USB host controller, USB hub, USB mass storage devices and ext4/jbd/f2fs filesystems are all built-in (rather than compiled as modules). So simply adding something like "root=/dev/sda1" might already be sufficient if it contains a root filesystem.

So, should I add that to config.txt file on the boot folder?

To /boot/cmdline.txt actually. Sorry, I forgot to mention that earlier.