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1986-07-07
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Copy Unprotecting King's Quest ][ Version 1.0W
by the Road Runner
July 4, 1986
In commemoration of 100 years of the Statue of Liberty, the accompanying
program and simple procedure will liberate your King's Quest ][ (Version 1.0W)
from the chains of copy protection, by creating a non-protected backup. To
create the backup, you will need:
. An IBM PC, XT, AT or compatible running DOS 2.0 or greater and
having a 360KB or 1.2M drive identified as A,
. The original King's Quest ][ (Version 1.0W) Diskettes 1 and 2,
. Two blank diskettes on which the backup will be made,
. Two diskette labels and two write protect tabs,
. The DOS program DISKCOPY (or equivalent),
. The accompanying program KQ2UNP.COM,
. These instructions.
Follow these simple steps:
1. Run DISKCOPY to make a backup of KQ-][ Disk 2 onto one of the blanks.
You should have no difficulty making this copy since Disk 2 is not protected.
Label the copy "KQ-][ Disk 2" and put a write protect tab on it.
2. Using DISKCOPY, make a backup of KQ-][ Disk 1 on the other blank
diskette. Since it is protected, you should expect to see an "Unrecoverable
read error on track 6" message, followed by a "Target disk may be unusable" at
the end of the copy. Ignore these warnings.
(NOTE: If you do -not- get the warnings, you may not have the right version of
KQ-][ and these procedures may not work. Instructions for unprotecting
earlier versions of KQ-][ can be found on several bulletin boards.)
3. Run program KQ2UNP and follow its directions:
. Insert the original KQ-][ Disk 1 in Drive A, then press ENTER,
. Remove the orginal, put the Disk 1 copy in Drive A, then press
ENTER.
4. Remove the backup, label it "KQ-][ Disk 1" and put a write protect
tab on it.
You are done!! Enjoy the freedom!!
------------------------------------------------------------------------------
For those of you who would like to know how the copy protection and copy
unprotection work, here is an overview of the details.
Copy Protection:
Track 6 Side 0 of KQ-][ Disk 1 has been specially formatted so that it cannot
be duplicated by most software disk copy programs. When KQ-][ is booted, it
eventually reads track 6 to determine that the special format is present.
Specifically, it reads track 6 side 0 sectors 8 to 2 (backwards) as 1024 byte
sectors, then reads sector 1 as an 8192-byte sector. It expects to find each
sector, and to get a CRC error on each read. If what is read is the expected
data, it assumes you have the original KQ-][ Disk 1, and runs the game. It
never makes this check again during the game.
Copy Unprotection:
The copy unprotection design takes advantage of several characteristics of the
KQ-][ copy protection scheme.
1. Most importantly, KQ-][ uses ROM BIOS INT 13 calls to read the
copy protected sectors, hence a demon can be introduced to intercept KQ-][
calls and fool the progam into believing it is reading the original.
2. The diskette is formatted with 9 512-byte sectors per track and
track 6 side 1 is not used by KQ-][. The 8192-byte sector of copy protected
data from side 0 can be stored in 16 of the 18 standard 512-byte sectors on
track 6 sides 0 and 1.
Program KQ2UNP reads the boot record and copy protected data from the original
KQ-][ Disk 1. On the copy, it writes a Road Runner produced boot record on
track 0, and a demon, the original boot record and copy protection data on
track 6.
When the KQ-][ copy is booted, the Road Runner boot record reads track 6 into
memory, installs the demon, then gives control to the original boot record.
The demon passes on all disk read requests to the ROM BIOS until KQ-][ asks
for track 6 data. It then feeds KQ-][ the copy protection garbage it expects,
until the last read call to track 6. The demon then uninstalls itself and
vanishes, leaving no trace.
------------------------------------------------------------------------------
Note: This program and writeup can also be used to unprotect The Black
Cauldron Version 1.1J.