Mapper 140 represents Jaleco's JF-11 and JF-14 boards, which act much like GNROM (66) except that the writable port is moved down to $6000-$7FFF.
Here are Disch's original notes:
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= Mapper 140 =
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Example Game:
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Bio Senshi Dan - Increaser Tono Tatakai
Notes:
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Regs lie at $6000-7FFF, so there's no SRAM
Registers:
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$6000-7FFF: [..PP CCCC]
P = Selects 32k PRG @ $8000
C = Selects 8k CHR @ $0000
Categories: In NesCartDB, INES Mappers, GNROM-like mappers