INES Mapper 151: Difference between revisions
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[[Category:iNES Mappers|151]][[Category:Bad iNES Mappers|151]] | [[Category:iNES Mappers|151]][[Category:Bad iNES Mappers|151]] | ||
[[iNES Mapper 151]] represents the [[VRC1]] on the [[Vs. System]]. Given that iNES [[INES#Flags_7|has a bit to mark]] "For Vs. System", this assignment was erroneous and any games marked thus should be [[iNES Mapper 075]] instead. | [[iNES Mapper 151]] represents the [[VRC1]] on the [[Vs. System]]. Given that iNES [[INES#Flags_7|has a bit to mark]] "For Vs. System", this assignment was erroneous and any games marked thus should be [[iNES Mapper 075]] instead. | ||
It is remotely conceivable that this is not true: FCEUX-2.1.5's and Nestopia-1.4.0's implementations of mapper 151 do not attach the [[VRC1#Mirroring_Control.2C_CHR_bits_.28.249000-.249FFF.29|5th bit of CHR bank]] onto the lower 4 and instead emulate all registers as 8 bits wide. | |||
However, no Vs. System games have more than 64KiB of CHR to verify the correct behavior against, and it is unlikely that a separate ASIC was made just for Vs. System games. | |||
Revision as of 18:13, 15 October 2012
iNES Mapper 151 represents the VRC1 on the Vs. System. Given that iNES has a bit to mark "For Vs. System", this assignment was erroneous and any games marked thus should be iNES Mapper 075 instead.
It is remotely conceivable that this is not true: FCEUX-2.1.5's and Nestopia-1.4.0's implementations of mapper 151 do not attach the 5th bit of CHR bank onto the lower 4 and instead emulate all registers as 8 bits wide.
However, no Vs. System games have more than 64KiB of CHR to verify the correct behavior against, and it is unlikely that a separate ASIC was made just for Vs. System games.
