INTRODUCTION
Thank you for your purchase of the Kracker Jax Revealed Trilogy.
The Trilogy is a compilation of our three separate Kracker Jax
Revealed books, Volumes 1 - 3. These books were individually
released over a period of two years, and represent countless hours
of investigation.
We've condensed Volumes One and Two into one book, while Volume
Three continues to be a separate book. All are included with your
purchase of the Trilogy.
The Kracker Jax Revealed series represents the best compilation
of this type of material ever assembled. The 3 Volumes were put
together from a mountain of raw data that was the end result of
years of hands on experience by people who were masters of the
craft of unlocking the mysteries of copy protection.
Inside these pages, you'll find the knowledge that will give you
the power to take complete control over your software. The step by
step instructions and detailed explanations have all been designed
to pass along years of practical experience to you in a very short
amount of time. Once you've finished the Revealed Trilogy, you may
want to read other similar material. You'll find our specific
recommendations listed under "Books For Further Reading" in the
Table Of Contents.
The path to knowledge is a rewarding one. We hope you enjoy the
journey.
K.J. REVEALED TRILOGY PAGE [1] (C)1990 K.J.P.B.
Tracks 1-35 details
The book "Kracker Jax Revealed Trilogy" gives a nice oversight on how
RapidLok tracks are organized. As pictures say more than 1000 words
I decided to visualize this using "screenshots" of some chosen tracks
inside a G64 image of my Microprose Pirates PAL disk side 1.
Figures #1+#2 below give a nice overview of the protection status of
all (data) tracks on a RapidLok protected disk. The name of the tool is
"RapidLok Scanner" for C64, and it's included on the disks "Bullseye",
"Kracker Jax REVEALED TRILOGY VOL 1-2", "RapidLok Utilities".
Figures #1+#2: Pirates G64 images scans. Left: side 1, right: side 2.
Obviously we have two types of tracks: Standard (DOS) formatted tracks
(marked green) and RapidLok formatted ones (marked red). "Version: 6"
means it's RapidLok6.
RapidLok formatted tracks
RapidLok formatted tracks 1-17 have 12 data sectors, read at bit rate
"11 = 307692 Bit/s". RapidLok formatted Tracks 19-35 have 11 data sectors,
read at bit rate "10 = 285714 Bit/s".
The following Figure #3 shows the typical header of a RapidLok formatted
Track ($1BE8 is track length). It starts with $14 bytes Sync mark (20x$FF)
at $24F3C, followed by the $7B "Extra sector" (starting with a $55 byte;
number of bytes (mostly $7B's) must match the corresponding Track Key
retrieved from the Track 36 Key Sector). Then a $29 Sync mark introduces
the 12-byte "DOS Reference header", which is actually a valid $52 DOS
sector header.
Directly following is the first RapidLok data sector. Each RapidLok data
sector consists of a header and the actual sector data, both preceded by
Sync marks of 5 bytes length - except the Track's first data sector after
the "DOS Reference header" having a $3E bytes long Sync mark (62x$FF)
before the header. Data sector headers start with $75, the following
header byte values are irrelevant for RapidLok. The data blocks start with
$6B and are about $255 bytes long (only first 3-4 lines of the $6B data
sector are shown in Figure #3 below, rest is omitted to keep the figure
small). All $6B data sectors have an embedded parity byte, so we'll notice
when a disk has bad sectors.
Keep in mind that all given byte lengths here may slightly vary from dump
to dump and disk to disk. And don't worry about the "$73" byte at offset
$24FF6 in Figure #3 below, such things may also happen. RapidLok routines
use tolerances.
Figure #3: RapidLok Track Header (Track 20).
Standard (DOS) formatted tracks
There are also tracks containing sectors in the usual standard DOS format
on a RapidLok protected disk. Those tracks have the usual number of
standard (DOS) sectors and are read with the usual standard (DOS) bit
rates. There are no tracks containing both standard (DOS) and RapidLok
sectors.
All those tracks simply start with a $14 bytes long Sync mark (20x$FF)
followed by a $7B "Extra sector" which is slightly different from the one
described above. This "Extra sector" starts with a $55 byte, followed by
a number of $7Bs and ends with a number of $AAs/$55s. The length of this
"Extra sector" is not checked against the corresponding Track 36 Keys.
The $52 "DOS reference sector" with its surrounding long Sync marks is
missing in DOS formatted tracks (as each DOS sector has such a reference
header).
The following Figures #4 and #5 show the track header on standard (DOS)
formatted tracks (the tools NIBREAD/NIBCONV seem to like positioning them
at the end of each Track - so I moved them to the start right after the
G64 Track length number for your convenience here).
Figure #4: Track header of standard DOS formatted Track (Track 5) - Type A.
Figure #5: Track header of standard DOS formatted Track (Track 6) - Type B.
Empty sectors
As on all standard DOS formatted disks there may be empty sectors on a
RapidLok protected disk as well. There are two types of them on RapidLok
protected disks: Empty sectors on a RapidLok formatted Track (see Figure
#6) and empty sectors on a standard DOS formatted Track (see Figure #7).
Empty RapidLok sectors are simply "$6B data blocks" with only $55-bytes
in them (slightly different length: about $25C bytes).
Empty standard DOS sectors are filled with $55-bytes (GCR) as well, have
a correct standard header but the first GCR bytes of the data block do
not decode to $07 ("Data descriptor byte" / data block ID). This is the
reason here why NIBREAD outputs "code 4" sector errors to the console.
Figure #6: Empty RapidLok sector (Track 7).
Figure #7: Empty standard DOS sector (Track 4).
As far as I have seen, $7B "Extra sectors" (with their long Sync marks)
can be removed without problems from standard (DOS) formatted tracks (even
from Directory Track 18).
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