Talk:MMC1: Difference between revisions
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Rainwarrior (talk | contribs) (SOROM, SUROM, SXROM, how are these mutually incompatible?) |
Rainwarrior (talk | contribs) m (→SOROM, SUROM, and SXROM: link fix) |
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== SOROM, SUROM, and SXROM == | == SOROM, SUROM, and SXROM == | ||
I'm a little fuzzy about why these are considered different [[NES 2.0 | I'm a little fuzzy about why these are considered different [[NES 2.0 submappers]]. The functionality of all three of these looks the same to me if the extra banking bits become useless/mirror when the ROM/RAM addressed is a smaller size (just like in any other mapper supporting various sizes). | ||
43210 | 43210 | ||
Revision as of 06:59, 8 August 2015
SOROM, SUROM, and SXROM
I'm a little fuzzy about why these are considered different NES 2.0 submappers. The functionality of all three of these looks the same to me if the extra banking bits become useless/mirror when the ROM/RAM addressed is a smaller size (just like in any other mapper supporting various sizes).
43210 +---+ PSSxC
4:P - A18 of 512k PRG ROM, disconnected if smaller 3:S - A13 of 16k PRG RAM, disconnected if smaller 2:S - A14 of 32k PRG RAM, disconnected if smaller 1:x - unused 0:C - 4k CHR banking control
What am I missing? I can't spot the incompatibility that necessitated the submappers? - Rainwarrior (talk) 00:58, 8 August 2015 (MDT)
