NES 2.0 Mapper 321: Difference between revisions
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NewRisingSun (talk | contribs) (Reassign this former mapper 287 duplicate to a mapper 287 variant.) |
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A~[011. .... ..PP MB..], A001.7=1, A001.6=0 | A~[011. .... ..PP MB..], A001.7=1, A001.6=0 | ||
|| |+---- PRG/CHR A17 | || |+---- PRG/CHR A17 | ||
|| +----- 0=PRG | || +----- 0=PRG A16..A13 from MMC3 | ||
|| 1=PRG | || 1=PRG A16..A15 from PP, | ||
|| PRG | || PRG A14..A13=CPU A14..A13 | ||
|| (NROM-256-like PRG banking) | || (NROM-256-like PRG banking) | ||
++------- PRG | ++------- PRG A16..A15 is M=1 |
Latest revision as of 09:20, 14 September 2022
NES 2.0 Mapper 321 denotes the 820310 MMC3-based multicart circuit board, UNIF MAPR BMC-820310-C. It is basically NES 2.0 Mapper 287 looking at differently-ordered address bits.
Outer Bank Register ($6000-$7FFF, write)
A~[011. .... ..PP MB..], A001.7=1, A001.6=0 || |+---- PRG/CHR A17 || +----- 0=PRG A16..A13 from MMC3 || 1=PRG A16..A15 from PP, || PRG A14..A13=CPU A14..A13 || (NROM-256-like PRG banking) ++------- PRG A16..A15 is M=1