So, to fix the BBB to only use the microSD when it's valid...
Requires: uenvcmd to be set in uEnv.txt and the "eMMC" has to use uuid's as the microSD is always /dev/mmcblk0 (eMMC can be 0 or 1)
This allows booting with an invalid boot microSD placed in the slot, and still works on the bone, as mmc dev 1 doesn't exist, so it'll just crash.. the status of the uenvcmd is pretty important...
This is really just a list of ideas/discussion...
So, to fix the BBB to only use the microSD when it's valid... Requires: uenvcmd to be set in uEnv.txt and the "eMMC" has to use uuid's as the microSD is always /dev/mmcblk0 (eMMC can be 0 or 1)
This allows booting with an invalid boot microSD placed in the slot, and still works on the bone, as mmc dev 1 doesn't exist, so it'll just crash.. the status of the uenvcmd is pretty important...
edit: using gist for formatting: https://gist.github.com/RobertCNelson/5511869