I wrote the Debian Jessie 8.3 image from BeagleBoard.org to an SD and was able to boot from it holding down the Boot button and using USB power.
I plugged in an Ethernet cable to the router and with puTTY was able to open an SSH terminal.
User: Debian
Password: temppwd (remember linux won’t show any keystrokes as you enter a password)
Now to see if I can copy the NAA image on to this bootable SD and write it to the eMMC.