INES Mapper 101

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This mapper was allocated for a naïve misdumping of the JF-10 board that contains Urusei Yatsura - Lum no Wedding Bell. JF-10 is identical to JF-09, which is the only mapper 87 game with 32KiB CHR. Both JF-10 and JF-09 only differ from all their predecessors (JF-05, -06, -07, and -08) by the addition of a single trace. In short, either mapper 87 should be capped to 16KiB CHR, or mapper 101 never had a hardware instantiation.

Supported in r3420 BizHawk, r2696 FCEUX (probably has been supported for eons), and reportedly MESS.

Registers:
---------------------------
 $6000-7FFF: [CCCC CCCC]
    C = Selects 8k CHR @ $0000

This is the same as mapper 87 but with the bits in order, and so has a better defined oversize extension; or the same as CNROM without bus conflicts.

Jaleco subsequently extended the JF-09 and JF-10 boards to add the ability to bank PRG in a GNROM-like manner. That was allocated to iNES Mapper 140.