NAME:       Dive Bomber
PUBLISHER:  Epyx
TYPE:       Airplane/Fighter Simulation

            Cracked from an original by DataWiz/6502 Crew

TECH NOTES:
Dive Bomber uses a very similar protection to World Games, the disk
format is standard DOS 3.3 with modified Address and Data Epilog
bytes of FF FF instead of DE AA.  The nibble counting routine was
exactly the same as in World Games, but I found another protection.
The 3rd stage boot code is stored on 3 encrypted sectors on the disk.
The decryption is done via an EOR, but the values are read from the
3 address epilog bytes on track $22, Sector $0F.  These 3 bytes are
effectively 'destroyed' when you make a copy of the disk.  By comparing
the differences between the encrypted and unencrypted code, I was able
to come up with the correct values.  I patched the existing code to
plug these correct values into the buffer and called the encryption
routine.  Voila-- cracked.

I believe the patch is on track 0, sector 5.  Don't have
my notes so I don't know what they originally were. :(

Njoi -- Dw

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If you encounter any other apparent protection,
please contact me at datawiz@magpage.com

If you have original apple software that has not yet been
converted to .DSK image format, please contact me.