------------The Coin Changer-----------
A 4am crack                  2016-01-16
---------------------------------------

Name: The Coin Changer
Genre: educational
Year: 1985
Publisher: Heartsoft, Inc.
Media: single-sided 5.25-inch floppy
OS: Diversi-DOS (T02,S02 has the string
  "C1982 DSR" backwards)
Previous cracks: none
Similar cracks:
  #575 Milt's Math Drills: Addition and
       Subtraction

                   ~

               Chapter 0
 In Which Various Automated Tools Fail
          In Interesting Ways


COPYA
  immediate disk read error

Locksmith Fast Disk Backup
  unable to read any track

EDD 4 bit copy (no sync, no count)
  works

Copy ][+ nibble editor
  modified address epilogues
  ("AA AA EB" instead of "DE AA EB")

Disk Fixer
  ["O" -> "Input/Output Control"]
    set Address Epilogue to "AA AA EB"
  all tracks readable
  T00 -> looks like a DOS 3.3 RWTS
  T11 -> DOS 3.3 disk catalog
  T01,S09 -> startup program is "HELLO"

Why didn't COPYA work?
  modified epilogue bytes (every track)

Why didn't Locksmith FDB work?
  modified epilogue bytes (every track)

EDD worked. What does that tell us?
  no half or quarter tracks
  almost certainly no nibble check
  (just structural changes to epilogue)

Next steps:

  1. capture RWTS with AUTOTRACE
  2. convert disk to standard format
     with Advanced Demuffin
  3. patch RWTS to read standard format

                   ~

               Chapter 1
In Which We Attempt To Use The Original
    Disk As A Weapon Against Itself


[S6,D1=original disk]
[S6,D2=blank disk]
[S5,D1=my work disk]

]PR#5
CAPTURING BOOT0
...reboots slot 6...
...reboots slot 5...
SAVING BOOT0
CAPTURING BOOT1
...reboots slot 6...
...reboots slot 5...
SAVING BOOT1
SAVING RWTS

]BRUN ADVANCED DEMUFFIN 1.5

["5" to switch to slot 5]

["R" to load a new RWTS module]
  --> At $B8, load "RWTS" from drive 1

["6" to switch to slot 6]

["C" to convert disk]

                 --v--

ADVANCED DEMUFFIN 1.5    (C) 1983, 2014
ORIGINAL BY THE STACK    UPDATES BY 4AM
=======PRESS ANY KEY TO CONTINUE=======
TRK:...................................
+.5:
    0123456789ABCDEF0123456789ABCDEF012
SC0:...................................
SC1:...................................
SC2:...................................
SC3:...................................
SC4:...................................
SC5:...................................
SC6:...................................
SC7:...................................
SC8:...................................
SC9:...................................
SCA:...................................
SCB:...................................
SCC:...................................
SCD:...................................
SCE:...................................
SCF:...................................
=======================================
16SC $00,$00-$22,$0F BY1.0 S6,D1->S6,D2

                 --^--

]PR#5
...
]CATALOG,S6,D2

C1983 DSR^C#254
292 FREE

 A 002 HELLO
 B 010 HRCG
 B 009 UTILITY-2.COINS
 B 008 COINS.LNK
 B 004 HEARTSOFT.CPRS
 T 002 TOP TEN 5
 A 003 HELLO.2
 B 005 TOPTEN.BAG.CPRS
 B 003 REDBOX.CPRS
 A 027 NICKEL
 A 025 PENNY
 B 009 COINS.TITLE.CPRS
 A 004 MENU
 B 003 QUARTER.CPRS
 B 003 NICKEL.CPRS
 B 002 PENNY.CPRS
 B 002 DIME.CPRS
 A 029 DIME
 A 029 QUARTER
 T 002 TOP TEN
 T 002 TOP TEN 25
 T 002 TOP TEN 10
 B 002 COIN.MLNK
 B 009 COIN.TITLE.CPRS
 B 005 LEVEL.BAG.CPRS
 B 003 MONEY.BAG.CPRS

]RUN HELLO
...works...

[S6,D1=demuffin'd copy]

]PR#6
...grinds...

My copy can't read itself yet. This is
not unusual.

                   ~

               Chapter 2
 In Which We Remove All Traces Of Copy
Protection Using An Automated Tool That
   I Wrote For Just Such An Occasion


[S6,D1=demuffin'd copy]
[S5,D1=my work disk]

]PR#5
]BRUN PDP

T00,S03,$91 change AA to DE
T00,S06,$AE change AA to DE

]PR#6
...works...

Quod erat liberandum.

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A 4am crack                     No. 578
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