INES Mapper 025

iNES Mapper 025 is used to represent the VRC4b (PCB 351406) and VRC4d (PCB 352400) variants of the VRC4 mapper, as well as the VRC2-using board 351948 used for Ganbare Goemon Gaiden: Keita Ougon Kiseru. The last has 8kB RAM (like VRC4) and doesn't divide the CHR bank numbers by two (unlike mapper 22).

 Here are Disch's original notes:
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 =  Mapper 025          =
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 Mapper 025 is a variant of VRC4, which is covered in another doc.
 
 For info, see mapper 021.