NES 2.0 Mapper 417

NES 2.0 Mapper 417 denotes the PCB of the "Fine Studio" bootleg copy of Batman: The Video Game (submapper 0) and of RoboCop (submapper 1).

Banks

• CPU $8000-$9FFF: 8 KiB switchable PRG-ROM bank
• CPU $A000-$BFFF: 8 KiB switchable PRG-ROM bank
• CPU $C000-$DFFF: 8 KiB switchable PRG-ROM bank
• CPU $E000-$FFFF: 8 KiB fixed PRG-ROM bank, last
• PPU $0000-$03FF: 1 KiB switchable CHR-ROM bank
• PPU $0400-$07FF: 1 KiB switchable CHR-ROM bank
• PPU $0800-$0BFF: 1 KiB switchable CHR-ROM bank
• PPU $0C00-$0FFF: 1 KiB switchable CHR-ROM bank
• PPU $1000-$13FF: 1 KiB switchable CHR-ROM bank
• PPU $1400-$17FF: 1 KiB switchable CHR-ROM bank
• PPU $1800-$1BFF: 1 KiB switchable CHR-ROM bank
• PPU $1C00-$1FFF: 1 KiB switchable CHR-ROM bank
• PPU $2000-$23FF: 1 KiB switchable CIRAM bank
• PPU $2400-$27FF: 1 KiB switchable CIRAM bank
• PPU $2800-$2BFF: 1 KiB switchable CIRAM bank
• PPU $2C00-$2FFF: 1 KiB switchable CIRAM bank

Registers

PRG-ROM Bank Select

Mask: $8073
Write to $8000: Select 8 KiB PRG-ROM bank at CPU $8000
Write to $8001: Select 8 KiB PRG-ROM bank at CPU $A000
Write to $8002: Select 8 KiB PRG-ROM bank at CPU $C000

CHR-ROM Bank Select

Mask: $8073
Write to $8010: Select 1 KiB CHR-ROM bank at PPU $0000
Write to $8011: Select 1 KiB CHR-ROM bank at PPU $0400
Write to $8012: Select 1 KiB CHR-ROM bank at PPU $0800
Write to $8013: Select 1 KiB CHR-ROM bank at PPU $0C00
Write to $8020: Select 1 KiB CHR-ROM bank at PPU $1000
Write to $8021: Select 1 KiB CHR-ROM bank at PPU $1400
Write to $8022: Select 1 KiB CHR-ROM bank at PPU $1800
Write to $8023: Select 1 KiB CHR-ROM bank at PPU $1C00

Additional meaning for Submapper 1:

Write to $8010: (bit 7) Select 1 KiB CIRAM bank at PPU $2000
Write to $8011: (bit 7) Select 1 KiB CIRAM bank at PPU $2400
Write to $8012: (bit 7) Select 1 KiB CIRAM bank at PPU $2800
Write to $8013: (bit 7) Select 1 KiB CIRAM bank at PPU $2C00

IRQ Control

Mask: $8070
Write to $8030: Reset counter and enable IRQ
Write to $8040: Disable and acknowledge IRQ

The counter increases on every M2 cycle regardless of IRQ enable status. If enabled, an IRQ is generated upon 10-bit (submapper 0)/12-bit (submapper 1) counter overflow.

CIRAM Bank Select (Submapper 0 only)

Mask: $8073
Write to $8050: Select 1 KiB CIRAM bank at PPU $2000
Write to $8051: Select 1 KiB CIRAM bank at PPU $2400
Write to $8052: Select 1 KiB CIRAM bank at PPU $2800
Write to $8053: Select 1 KiB CIRAM bank at PPU $2C00