6) Inspection of the disk log tells us that the file BSSO is
the likely candidate to contain the protection code. You may, as
we did, load BSSO and inspect the proper addresses to ensure our
save is to the proper file. Then, when satisfied, just redo step
five and, when the code has been replaced again1 save the file
back to your BACKUP disk. The disk log tells us the file resides
for $0800-$1600. Be sure to add one byte to the end address
<> S "@0:BSSO",08,0800,1601 <>.
When this save is complete, your backup will be completely broken,
and may be copied with any fast copier. For those who want to
inspect the protection code, just load in the BSSO file and do a GO
to 09E1. After about one second, reset out and re-SYS the monitor
in and inspect that memory area. You'll find the protection code
intact. If you allow the drive to run for long, the protection code
will be replaced by valid program code.
EXPRESS RAIDER : DATAEAST
Procedure:
Loading the original disk produces a rattle free load, and an
error scan shows no standard errors. A backup made with the C-64
Fast Copier produces a non working copy, A backup made with a
nybbler produces the same non working backup. Before starting to
work on this title, make a fast-copier backup and a formatted work
disk. Because the only file on the directory of this title is the
loader, special procedures will be required. You will need a reset
button of some sort.
Working with your backup:
1) With the reset switch in place, load the backup three or
four times to get the feel of when the program stalls. When you
have gotten the timing down, try to reset the computer just before
that stall occurs. You will hear the head swing out if you are
too late. We want to reset just before it does. After reset,
from the Utility disk, load the $C000 monitor
< LOAD "49152",8,1 > and after the load sys it in .
2) If you have performed previous breaks in Section E, you
will remember that we are looking for a decrypter that hides the
protection check. That decrypter ALWAYS begins with A0 00 A9. So
we can search most of memory, flip out the BASIC Interpreter by
changing memory location $0001 from a $37 to a $36 ($76 on the
C-128) < M 0001 >. Now do a hunt for the key bytes in memory
< H 0800 BFFF AO 00 A9 >. If you have reset out at the proper
time, the following addresses will be returned: 84C0 8759 9629
K.J. REVEALED TRILOGY PAGE [58] (C)1990 K.J.P.B.
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