NES 2.0 Mapper 373: Difference between revisions
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NewRisingSun (talk | contribs) (Created page with "{{DEFAULTSORT:373}}Category:Multicart mappersCategory:MMC3-like mappersCategory:Mappers with scanline IRQs NES 2.0 Mapper 373 is used for a ''Super 4-in-1'' multic...") |
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|||+------ Select CHR A18 | |||+------ Select CHR A18 | ||
||+------- Select MMC3 (0)/GNROM-like (1) PRG mode | ||+------- Select MMC3 (0)/GNROM-like (1) PRG mode | ||
++-------- Select CHR A20-A21 and PRG | ++-------- Select CHR A20-A21 and PRG A21-22 | ||
In GNROM-like mode, the MMC3 clone's CPU A14 input is held low, so that MMC3 registers #6 and #7 apply both to $8000/$C000 and $A000/$E000, with the bank number ANDed with NOT $02 in the lower range and ORed with $02 in the upper range. | In GNROM-like mode, the MMC3 clone's CPU A14 input is held low, so that MMC3 registers #6 and #7 apply both to $8000/$C000 and $A000/$E000, with the bank number ANDed with NOT $02 in the lower range and ORed with $02 in the upper range. | ||
Latest revision as of 16:32, 6 July 2019
NES 2.0 Mapper 373 is used for a Super 4-in-1 multicart (PCB ID SFC-13). It is INES Mapper 045 but with one bit of outer bank register #2 working as a GNROM switch.
CHR-AND, CHR-OR/PRG-OR MSB, CHR source ($6000 #2, write)
Mask: $F001 D~7654 3210 --------- PPRC cccc |||| ++++- Select number of CHR bits from MMC3 |||| ($F: 256 KiB, $E: 128 KiB ... $7-$0: 1 KiB) |||+------ Select CHR A18 ||+------- Select MMC3 (0)/GNROM-like (1) PRG mode ++-------- Select CHR A20-A21 and PRG A21-22
In GNROM-like mode, the MMC3 clone's CPU A14 input is held low, so that MMC3 registers #6 and #7 apply both to $8000/$C000 and $A000/$E000, with the bank number ANDed with NOT $02 in the lower range and ORed with $02 in the upper range.
