INES Mapper 074: Difference between revisions
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It's identical to [[iNES Mapper 192]] and used for the same reason, except that only pages 8 and 9 are RAM. | It's identical to [[iNES Mapper 192]] and used for the same reason, except that only pages 8 and 9 are RAM. | ||
If the [[NES 2.0]] header is present, 74 and 192 should be emulated identically, as NES 2.0 specifies CHR RAM size elsewhere. | If the [[NES 2.0]] header is present, 74 and 192 should be emulated identically, as NES 2.0 specifies CHR RAM size elsewhere. | ||
BizHawk supports this mapper as of r3973; FCEUX and FCEU-MM have supported them for a long time but definitely as of 26-nov-2012, although CRC checks for m192<->m074 may be lacking. | |||
Some games will be mis-headered as m074 but should really be m192 and will either need to be changed to the correct mapper, or changed to the correct amount of CHR RAM and handled by unified code. | Some games will be mis-headered as m074 but should really be m192 and will either need to be changed to the correct mapper, or changed to the correct amount of CHR RAM and handled by unified code. | ||
Revision as of 21:13, 26 November 2012
iNES Mapper 074 is a MMC3 clone used in Eastern games. It's identical to iNES Mapper 192 and used for the same reason, except that only pages 8 and 9 are RAM. If the NES 2.0 header is present, 74 and 192 should be emulated identically, as NES 2.0 specifies CHR RAM size elsewhere.
BizHawk supports this mapper as of r3973; FCEUX and FCEU-MM have supported them for a long time but definitely as of 26-nov-2012, although CRC checks for m192<->m074 may be lacking.
Some games will be mis-headered as m074 but should really be m192 and will either need to be changed to the correct mapper, or changed to the correct amount of CHR RAM and handled by unified code.
Here are Disch's original notes: ======================== = Mapper 074 = ======================== aka: -------------------------- Pirate MMC3 variant Example Games: -------------------------- Di 4 Ci - Ji Qi Ren Dai Zhan Ji Jia Zhan Shi Notes: -------------------------- This mapper is a modified MMC3 (or is based on MMC3?). In addition to any CHR-ROM present, there is also an additional 2k of CHR-RAM which is selectable. CHR pages $08 and $09 select CHR-RAM, other pages select CHR-ROM Apart from that, this mapper behaves exactly like your typical MMC3. See mapper 004 for details.
