and place it into the drive. Using the Memory Command, change
the PHA(48) at $384D to a BRK(00) < M 384D >. We can now
execute the protection code from the original and the value
in the left in the A register when the code breaks will be
the numeric value we're looking for. Execute the code by
typing .
D) The opening screen will again appear and input N again and
the load will continue. This time the head will swing out and
a few moments later the program will break. The registers
will be on the screen. Note the A register has a value of 58.
This is the value we're looking for. (Those who want to
inspect the drive routine that checks protection may find it
starting at $C800.)
E) The break is now quite simple. We can replace the JSR C800
instruction with the value and totally skip the protection
check. By replacing it with A9 58 EA (LDA 58 NOP) we can
directly load the accumulator with a 58 which then will be
pushed onto the stack. Let's make our changes with Disk
Doctor.
F) Using the converter in Hesmon, find the decimal equivalent to
A9 58 EA. In a clear work space type <$ 00A9>. The decimal
value 169 will be returned. The same procedure for 0058 and
00EA will return 88 and 234 respectively. Power down and
remove Hesmon. From the Utility Disk, load Disk Doctor and
again insert the backup into the drive. At Track 18/Sector 1,
position 34, you'll find the Prg byte for the GM1 file. Place
the cursor on the Track pointer at position 35 and press
to Jump to Link. You'll be taken to Track 17/Sector 1.
Starting at position 0 cursor along and look for the hex
bytes 20 00 C8 (JSR C800) pattern. At position 78 you'll find
the first byte of that pattern. Use the ~ key to change three
bytes starting at position 78 to 169, 88, 234 (decimal
equivalent). Hit the key to rewrite the sector and then
for yes. Your title is now free from all protection and
may even be file copied if desired.
FAULKLANDS 82 : FIREBIRD
Procedure:
Loading the original disk reveals the GMA symbol on the opening
loader screen. A fast copy when booted, locks up the drive and
sends it into an endless spin. Before starting, make a fast copy
using our C-64 Fast Copy. Repair the directory according to the
step one instructions. Be sure to validate the disk and do a log
K.J. REVEALED TRILOGY PAGE [72] (C)1990 K.J.P.B.
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