INES Mapper 250: Difference between revisions
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[[Category:INES Mappers|250]] | [[Category:INES Mappers|250]][[Category:MMC3-like mappers|250]] | ||
INES Mapper 250 is a mapper by Nitra, | [[INES Mapper 250]] is a mapper by Nitra, used for pirate games such as [[wikia:c:bootleggames:Time Diver: Avenger|Time Diver Avenger]] and the Queen Bee V. | ||
Hardware consists of regular MMC3 chip connected in different way: | |||
* A10 instead of A0 is used to determine which register to write to (i.e. the registers are at $8000, $8400, $A000, $A400, $C000, $C400, $E000, $E400 and their associated | |||
* A7..A0 is used instead of D7..D0: the value written to each register is the lower byte of the address (i.e. address AND $00FF), data value is discarded | |||
* Queen Bee V contains also 74153 mux which controls PRG-A13 resulting in the following change: | |||
below | |||
$8000 $8000 $a000 $c000 $e000 | |||
0 MMC3 MMC3 0 1 | |||
Source: [http://krzysiobal.com/carts/?action=search&mpr=250] |
Latest revision as of 20:10, 14 April 2023
INES Mapper 250 is a mapper by Nitra, used for pirate games such as Time Diver Avenger and the Queen Bee V.
Hardware consists of regular MMC3 chip connected in different way:
- A10 instead of A0 is used to determine which register to write to (i.e. the registers are at $8000, $8400, $A000, $A400, $C000, $C400, $E000, $E400 and their associated
- A7..A0 is used instead of D7..D0: the value written to each register is the lower byte of the address (i.e. address AND $00FF), data value is discarded
- Queen Bee V contains also 74153 mux which controls PRG-A13 resulting in the following change:
below $8000 $8000 $a000 $c000 $e000 0 MMC3 MMC3 0 1
Source: [1]