[beagleboard] BBB Boot As BB "Classic"

HDMI cannot really be disabled. As all its pins are inputs so they should not interfere with their usage. Don’t connect a HDMI cable and the HDMI framer should not be active.

As to the eMMC, connect the board to your PC over USB. Open the storage drive that appears and delete the files. After that It will not be able to boot and wil force the boot to uSD slot as the second option…