Sadly, the broken unit's USB software is getting the bad flash-chip data problem with loading dlls. So even though the hardware is working, it won't mount a USB stick.
My working unit however is fine, it mounts sticks as readonly though - so you need to "mount -uw /fs/usb0" (had problems with this at first, said it couldn't do it because it may be read only - yeah, that's what I'm trying to fix!) or "mount -uw /dev/hd0" (maybe doing this one helped with that problem? Dunno, I just run both now - same device)...
Got about 8255 files which come to 101MB off my working screen, found these 2 files (largest pictures when I did a search):
I need to remember to "mount -ur ..." to put it back as read only before I pull out the stick, but the "shutdown" command also works - nice, shuts down the unix os at which point it reboots (where I can pull out the stick before it is re-scanned).
I guess I really need to pull apart my spare GPS screen and dump it - see what extras it has.
I was also able to write to files on the screen (I attempted to change the usb_mode.conf file to say "RW" instead of "RO" - which I could do easily enough - but it still didn't mount the stick as read/write even after a reboot).
Gosh it's been smokey here in Canberra.