NES 2.0 Mapper 386

NES 2.0 Mapper 386 denotes J.Y. Company's YY860729C circuit board, used for only one known multicart:

• 1996 Super HiK 5-in-1 (JY-090)

It uses the J.Y. Company ASIC, has 1 MiB of PRG-ROM and CHR-ROM each, and is similar to NES 2.0 Mapper 282 but has the Outer Bank register bits in a different order. NES 2.0 Mapper 387 is almost the same but changes the outer PRG bank size from 256 to 128 KiB.

Outer Bank Register ($D003)

Mask: $F003

7654 3210
---- ----
..L? PCpc
  || |||+- CHR A18, ignored if L=1
  || ||+-- PRG A18
  || |+--- CHR A19
  || +---- PRG A19
  |+------ Always 1
  +------- Select outer CHR-ROM bank size
            0: Mask $900x/$A00x to 256 KiB, use c
            1: Mask $900x/$A00x to 512 KiB, ignore c   

For a description of all other registers, see J.Y. Company ASIC.