2012-03-31 20:53:14 +00:00
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using System;
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using System.Collections.Generic;
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using System.Linq;
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using System.Text;
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namespace BizHawk.Emulation.Consoles.Atari._2600
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{
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2012-04-29 21:01:06 +00:00
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/*
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4A50 (no name)
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-----
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Upon review, I don't think this method is terribly workable on real
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hardware. There's so many problems that I kinda gave up trying to
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count them all. Seems that this is more of a "pony" method than something
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actually usable. ("pony" referring to "I want this, and that, and that, and
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a pony too!")
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One major problem is that it specifies that memory can be read and written
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to at the same address, but this is nearly impossible to detect on a 2600
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cartridge. You'd almost have to try and figure out what opcodes are being
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run, and what cycle it's on somehow, all just by watching address and
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data bus state. Not very practical.
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The other problem is just the sheer volume of things it is supposed to do.
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There's just tons and tons of unnecessary things like attempting to detect
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BIT instructions, handling page wraps and other silly things.
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This all supposidly fit into a Xilinx XC9536XL but I am not sure how the
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chip could handle the RAM issue above at all. It almost needs to see R/W
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and M2 (clock) to be able to properly do most of the things it's doing.
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*/
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2012-03-31 20:53:14 +00:00
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class m4A50 : MapperBase
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{
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}
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}
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