Talk:INES Mapper 027

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VRC4 actually supports 9 pin wide CHR banking, making this look awfully like the VRC4"f" (mapper 23) variant... other than whatever weirdness is going on with the definition of $9002. (Is this 3x8+8F PRG banking or MMC3 style PRG banking?) ... and whether the scanline irq behavior is A12-based or M2-based —Lidnariq (talk) 20:39, 2 March 2013 (MST)

The scanline IRQ must be M2-based: the game was re-released in a later version that includes an NTSC/PAL selection screen at the beginning. This would not be necessary if the counter were PA12-based. I do not understand the question about the $9002 register; it seems just like the VRC4's PRG Swap Mode functionality. All in all, it seems to be bog-standard VRC4f to me, and runs perfectly when emulated as such. I propose following FCEUX in using INES Mapper 027 solely for 迷魂車 (Míhúnchē) (CC-27) and using Mapper 23.1 for World Hero. NewRisingSun (talk) 10:58, 24 May 2019 (MDT)
After re-reading the description a number of times, I now understand what is meant by "3x8+8F vs MMC3-style PRG banking" --- basically, a VRC4 equivalent of INES Mapper 100. NewRisingSun (talk) 11:15, 24 May 2019 (MDT)
Also, whatever led Nestopia to put a copy of the $9002 "geometry" register at $9080?—Lidnariq (talk) 05:34, 25 May 2019 (MDT)