Crack Down: Difference between revisions
New release: Crack Down (Sega), dump by sncboom2k |
Verification remarks removed |
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| NTSC or PAL || NTSC | | NTSC or PAL || NTSC | ||
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| Protection || | | Protection || Manual Lookup | ||
|- | |- | ||
| Working? || Yes | | Working? || Yes | ||
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<gallery> | <gallery> | ||
File:CrackDown sncboom2k NTSC Sega_a_dos_r1.png|Side 0 | File:CrackDown sncboom2k NTSC Sega_a_dos_r1.png|Side 0 | ||
</gallery> | </gallery> | ||
<gallery> | <gallery> | ||
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The disk ("CRACKDOWN") shows the files "*" and "0" in the directory; the game is loaded with its own fast loader. The disk has no read errors. | The disk ("CRACKDOWN") shows the files "*" and "0" in the directory; the game is loaded with its own fast loader. The disk has no read errors. | ||
The tracks 36 to 40 of side 0 and all tracks of side 1 contain no data, they are written with a continuous signal (only 1 bits). The game | The tracks 36 to 40 of side 0 and all tracks of side 1 contain no data, they are written with a continuous signal (only 1 bits). The game does not need the tracks 36 to 40 to start. | ||
==== Streams ==== | ==== Streams ==== | ||
[[File:Streams CrackDown sncboom2k NTSC Sega.zip]] | [[File:Streams CrackDown sncboom2k NTSC Sega.zip]] | ||
| Line 60: | Line 59: | ||
Disk side 1 is empty. | Disk side 1 is empty. | ||
==== Disk Protection ==== | ==== Disk Protection ==== | ||
After the start the game asks for a word from the manual ("Enter the word at the top left / top right / bottom left / bottom right of page 1 to 8"). The words are not stored on the disk: the routine at $C700 calculates a checksum over the entered word (start value $64, each character is shifted left by one bit and EOR-ed to the checksum) and compares it with the entry for the selected page and position in a table of 32 values ($C7AE) and with one additional value ($72, $C7CE) that is accepted for every question. After a correct word the loader is patched ($49 is written to $C1A4); after three wrong words the game continues without this patch and crashes with a black screen | After the start the game asks for a word from the manual ("Enter the word at the top left / top right / bottom left / bottom right of page 1 to 8"). The words are not stored on the disk: the routine at $C700 calculates a checksum over the entered word (start value $64, each character is shifted left by one bit and EOR-ed to the checksum) and compares it with the entry for the selected page and position in a table of 32 values ($C7AE) and with one additional value ($72, $C7CE) that is accepted for every question. After a correct word the loader is patched ($49 is written to $C1A4); after three wrong words the game continues without this patch and crashes with a black screen. | ||
Every entry with the checksum $72 is accepted for every question, for example "AJ" | Every entry with the checksum $72 is accepted for every question, for example "AJ" or "MAIN". Which word the developers intended for this value is not known, only the checksum is stored. | ||
The manual that fits this check (at least 8 pages) is missing: no scan of the manual of this release is known. The instruction sheet of the European U.S. Gold release has only one page and does not fit. | The manual that fits this check (at least 8 pages) is missing: no scan of the manual of this release is known. The instruction sheet of the European U.S. Gold release has only one page and does not fit. | ||
Latest revision as of 18:44, 14 November 2026
Crack Down, C64 version of the Sega arcade game: two agents, Ben and Andy, have to place time bombs in the enemy base and leave it before the time runs out.
Source 1
| Property | Data |
|---|---|
| Title | Crack Down |
| Publisher and/or Developer | Sega |
| Year | 1990 |
| Disk(s) | 1 |
| Number of Index Holes | ? |
| Media Type | 5.25 DSDD |
| Retail, Budget or Compilation (with name) | Retail |
| Country of Release | US |
| Language(s) | English |
| Platform | C64 |
| NTSC or PAL | NTSC |
| Protection | Manual Lookup |
| Working? | Yes |
| Archived | 09 Mar 2013 sncboom2k |
| Verified by | enigma |
-
Side 0
-
Manual check -
Title -
Game
sncboom2k: Sega (no photos).
The disk ("CRACKDOWN") shows the files "*" and "0" in the directory; the game is loaded with its own fast loader. The disk has no read errors.
The tracks 36 to 40 of side 0 and all tracks of side 1 contain no data, they are written with a continuous signal (only 1 bits). The game does not need the tracks 36 to 40 to start.
Streams
File:Streams CrackDown sncboom2k NTSC Sega.zip
G64
File:CrackDown sncboom2k NTSC Sega s0.g64
Disk side 1 is empty.
Disk Protection
After the start the game asks for a word from the manual ("Enter the word at the top left / top right / bottom left / bottom right of page 1 to 8"). The words are not stored on the disk: the routine at $C700 calculates a checksum over the entered word (start value $64, each character is shifted left by one bit and EOR-ed to the checksum) and compares it with the entry for the selected page and position in a table of 32 values ($C7AE) and with one additional value ($72, $C7CE) that is accepted for every question. After a correct word the loader is patched ($49 is written to $C1A4); after three wrong words the game continues without this patch and crashes with a black screen.
Every entry with the checksum $72 is accepted for every question, for example "AJ" or "MAIN". Which word the developers intended for this value is not known, only the checksum is stored.
The manual that fits this check (at least 8 pages) is missing: no scan of the manual of this release is known. The instruction sheet of the European U.S. Gold release has only one page and does not fit.