our code in and short circuit the protection check. Let's begin
here.
6) Reload the 1985 file to provide fresh undecrypted code
< L " 198*",08 >. First let's move the decrypter to the
outside bounds of this file. Since the file ends at $143F we can
move it to $1440. Use the Transfer command < T 139B 13BC 1440 >.
Disassemble code at $1440 and cursor down through the
moved decrypter. You'll find the last byte, a $60 at $1461. This
will become the new end address of this file.
7) Now that the decrypter has been moved, lets prepare the work
space. Fill the area from $1395-$13BC with NOPs
< F 1395 13BC EA >. Now let's use the assembler in Hesmon to
rewrite the code in our work spot. A printout of the prior code
to compare with our changes should make the reasons for our
changes clear. We can start writing our code a $139A. Start by
using the assemble command < A 139A >. Here's the code to
write.
A 139A JSR 1440 : Decrypt code from new decrypter location.
JSR 1206 : Set up for protection. --code from here
LDA #$00 : Substitutes for protection --to here will
--replace
STA 1293 : check at $118E --the JSR 1184 at
JSR 1269 : --$13BD.
JMP 13C0 : Jump around JSR 1184 at $13BD, which is no
longer needed
8) When done, hit return a few times to a clear spot and
Disassemble code and check to make sure the changes are correct
< D 139A >. If all is well, all that's left is to scratch the
old file and save the new. X to BASIC and scratch the 1985
file. < OPEN15,8,15,"S0: 1985 " >. Be sure to use two spaces
before 1985 and three spaces after. When done, hit Run/Stop-
Restore to re-enter the monitor and save the new 1985 file. Our
new start/end addresses are $1000-$1461+1.
< S " 1985 " 08 1000 1462 > You're backup is now completely
broken and may be fast copied. You can't file copy this title
because of the various Block-Executes used in the loader for the
fast load routine as well as protection checks. These
Block-Executes access code not allocated by directory files.
TRIO : SOFTSYNC
Procedure:
Loading the original disk produces a rattle free load, and an
K.J. REVEALED TRILOGY PAGE [36] (C)1990 K.J.P.B.
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