INES Mapper 020: Difference between revisions

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m (then it isn't really used for carts and is thus categorized as "bad" per the definition in Mapper)
(link to the format that is used for game disk images)
 
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[[Category:iNES Mappers|020]][[Category:Bad iNES Mappers|020]]
[[Category:iNES Mappers|020]][[Category:Bad iNES Mappers|020]]
Mapper 20 is defined as reserved for the Famicom Disk System ([[FDS]]) in official [[iNES]] specs.
Mapper 20 is defined as reserved for the Famicom Disk System ([[FDS]]) in official [[iNES]] specs.
Ie. the mapper number is mostly intended for being internally used by emulators (to indicate to themselves that they are emulating the FDS hardware).
The mapper number is mostly intended for being internally used by emulators (to indicate to themselves that they are emulating the FDS hardware).


The mapper number could be theoretically used for the FDS BIOS ROM-image, but this isn't done in practice. The FDS BIOS is typically assingned as [[NROM]] (if it is dumped in [[iNES]] format), or it's stored as raw BIOS dump (without iNES header and without mapper number).
Actual FDS game disk images normally use the [[FDS disk format]].
 
The mapper number could be theoretically used for the FDS BIOS ROM-image, but this isn't done in practice. The FDS BIOS is typically stored as [[NROM]] if it is dumped in [[iNES]] format, or it's stored as raw BIOS dump (without iNES header and thus without mapper number).

Latest revision as of 03:44, 17 May 2020

Mapper 20 is defined as reserved for the Famicom Disk System (FDS) in official iNES specs. The mapper number is mostly intended for being internally used by emulators (to indicate to themselves that they are emulating the FDS hardware).

Actual FDS game disk images normally use the FDS disk format.

The mapper number could be theoretically used for the FDS BIOS ROM-image, but this isn't done in practice. The FDS BIOS is typically stored as NROM if it is dumped in iNES format, or it's stored as raw BIOS dump (without iNES header and thus without mapper number).