Copying Ultima I (new version)

[dkwan@transmeta.com (Doug Kwan)]

I have a copy of the Ultima I and I want to back up the game. I used to
be good at cracking in my teens but I am not sure if I still got all my
skills. Neverthese, I believe I made a de-protected copy of them. The
protection used seems to be simple. The address field headers on even
tracks are "D5 AA 96" and those on the odd track are "D4 AA 96". The disk
volume is 1 instead of the usual 254. There are also grabage in the epilogue
of the address field. I hacked RWTS in DOS so that it accepts either D5 or D4
in the first header byte and ignores the address field epilogue. The copy I
made boots fine on my IIe and I can play the game and save it. 

Does anyone know if there are other protection other than those I found? 
Is the "grabage" at the epilogue really garbage? I search the web and
there is no document about deprotecting/copying Ultima I.

Yes, I could save the touble by getting an disk image from asimov but I hate
the crack screen when I own the real thing. :D

Doug