-----------------Cogito----------------
A 4am crack                  2016-07-14
---------------------------------------

Name: Cogito
Genre: educational
Year: 1984
Authors: Michael Merbert
Publisher: Reader's Digest Services
Platform: Apple ][+ or later
Media: single-sided 5.25-inch floppy
OS: DOS 3.3
Previous cracks: none

This disk was automatically cracked by
Passport. Here is the transcript:

                 --v--

READING FROM S6,D1
T00,S00 FOUND DOS 3.3 BOOTLOADER
USING DISK'S OWN RWTS
WRITING TO S6,D2

THE DISK WAS COPIED SUCCESSFULLY, BUT
PASSPORT DID NOT APPLY ANY PATCHES.

POSSIBLE REASONS:
- THE SOURCE DISK IS NOT COPY PROTECTED.
- THE TARGET DISK WORKS WITHOUT PATCHES.
- THE DISK USES AN UNKNOWN PROTECTION,
  AND PASSPORT CAN NOT HELP ANY FURTHER.

                 --^--

More information and source code is
available at
https://archive.org/details/Passport4am

                   ~

In this case, the cracked copy does not
require any patches, because its custom
RWTS can also read standard disks. (It
accepts virtually any nibble for the
third data prologue.)

                 --v--

T00,S02
----------- DISASSEMBLY MODE ----------
00DC:A0 20          LDY   #$20
00DE:88             DEY
00DF:F0 61          BEQ   $0142

; match first data prologue nibble
00E1:BD 8C C0       LDA   $C08C,X
00E4:10 FB          BPL   $00E1
00E6:49 D5          EOR   #$D5
00E8:D0 F4          BNE   $00DE
00EA:EA             NOP

; match second data prologue nibble
00EB:BD 8C C0       LDA   $C08C,X
00EE:10 FB          BPL   $00EB
00F0:C9 AA          CMP   #$AA
00F2:D0 F2          BNE   $00E6
00F4:A0 56          LDY   #$56

; accept any non-$AA value for third
; data prologue nibble
00F6:BD 8C C0       LDA   $C08C,X
00F9:10 FB          BPL   $00F6
00FB:C9 AA          CMP   #$AA
00FD:F0 F7          BEQ   $00F6

                 --^--

Quod erat liberandum.

---------------------------------------
A 4am crack                     No. 707
------------------EOF------------------