Boot Modes¶
On Yggdrasil, a 2 bit DIP switch can be found above the Display. The value configured on it is used during bootup of the plugged in World Board to determine where to boot from.
Since the configuration varies between different SoCs, here’s a list of all possible modes for all existing World Boards.
Midgard¶
BOOT0 |
BOOT2 |
Description |
|---|---|---|
OFF |
OFF |
Boot from Flash at Address |
ON |
OFF |
Boot from internal Bootloader at Address |
OFF |
ON |
Boot from Flash at Address |
ON |
ON |
Boot from internal Bootloader at Address |
Asgard¶
BOOT0 |
BOOT2 |
Description |
|---|---|---|
OFF |
OFF |
Boot from a Serial interface (UART or USB) |
ON |
OFF |
Boot from a Serial NOR Flash over QUADSPI |
OFF |
ON |
Engineering mode for development with the CubeIDE |
ON |
ON |
BOOT from SD-Card on SDMMC1 |
If booting fails because no FSBL can be loaded from the selected source, Asgard automatically retries from a Serial interface.