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PostPosted: Fri Jan 20, 2006 8:27 pm 
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Is it possible that the reads from $2006 return any meaningful information? Does anyone know anything about this?

Thanks!


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PostPosted: Fri Jan 20, 2006 10:11 pm 
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Reading $2006 does not return any meaningful data - it just happens to give you the last data that was recently* on the PPU I/O bus (i.e. the last value you read from or wrote to $2000-$2007).

* the value likely decays fairly quickly

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PostPosted: Fri Jan 20, 2006 10:16 pm 
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Oh, OK. Thanks Quietust.


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PostPosted: Fri Jan 20, 2006 10:51 pm 
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Is that due to the capacitance of the bus lines?


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PostPosted: Sat Jan 21, 2006 12:15 am 
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Quote:
Reading $2006 does not return any meaningful data - it just happens to give you the last data that was recently on the PPU I/O bus


I think this qualifies as meaningful (but not reliable). A game could even erroneously rely on the data, perhaps reading the correct register then attempting to read a write-only register shortly after and expecting the original data.


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PostPosted: Sat Jan 21, 2006 10:15 pm 
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You might find this worth reading. :)


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