INES Mapper 143: Difference between revisions
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(NROM plus "pathetic" copy protection ... but it's less pathetic than CNROM's diodes.) |
NewRisingSun (talk | contribs) (Not worthy of a direct quote.) |
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[[iNES Mapper 143]] denotes an NROM circuit board with a simple form of protection: | |||
* ''Dancing Blocks'' | |||
* ''Magical Mathematics'' (NTSC version only) | |||
The functional description is consistent with a [[74138]] and a 74368. | The functional description is consistent with a [[74138]] and a 74368. | ||
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++--------- open bus | ++--------- open bus | ||
Nestopia additionally implies that at least ''Dancing Blocks'' relies extensively on the values of uninitialized memory, and so manually sets the emulated | Nestopia additionally implies that at least ''Dancing Blocks'' relies extensively on the values of uninitialized memory, and so manually sets the emulated console's 2K of internal RAM to a different pattern than Nestopia's default. | ||
* http://cah4e3.shedevr.org.ru/%5Blst%5D-sachen-mappers.txt | * http://cah4e3.shedevr.org.ru/%5Blst%5D-sachen-mappers.txt | ||
Latest revision as of 09:28, 12 June 2019
iNES Mapper 143 denotes an NROM circuit board with a simple form of protection:
- Dancing Blocks
- Magical Mathematics (NTSC version only)
The functional description is consistent with a 74138 and a 74368.
Reads from these addresses produce this output:
A:[010. ...1 ..DD DDDD] -> [xxii iiii]
|| |||| |||| ||||
++-++++------||++-++++-- reads provide the logical inversion of DDDDDD in the bits iiiiii
++--------- open bus
Nestopia additionally implies that at least Dancing Blocks relies extensively on the values of uninitialized memory, and so manually sets the emulated console's 2K of internal RAM to a different pattern than Nestopia's default.
