Failure to boot from fresh alpine-xen USB install

I have installed alpine-xen onto a ext3 USB stick and I get the following error on boot:

FAT-fs (sdb1): utf8 is not a recommented IO charset for FAT filesystems, filesystem will be case sensitive
FAT-fs (sdb1): utf8 is not a recommented IO charset for FAT filesystems, filesystem will be case sensitive
FAT-fs (sdb1): utf8 is not a recommented IO charset for FAT filesystems, filesystem will be case sensitive
FAT-fs (sdb1): utf8 is not a recommented IO charset for FAT filesystems, filesystem will be case sensitive
FAT-fs (sdb1): utf8 is not a recommented IO charset for FAT filesystems, filesystem will be case sensitive
failed.
initramfs emergency recovery shell alunched. Type 'exit' to continue boot
sh: can't access tty; job control turned off
#

The keyboard can't send interrupts after that.

Has anyone seen this before? I'll play a bit more a bit later