NES 2.0 Mapper 417: Difference between revisions

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(Created page with "{{DEFAULTSORT:417}}Category:Mappers with cycle IRQs '''NES 2.0 Mapper 417''' denotes the PCB of the "Fine Studio" bootleg copy of ''Batman: The Video Game''. =Banks= * CP...")
 
m (→‎IRQ Control: fix formatting)
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The counter increases on every M2 cycle regardless of IRQ enable status. If enabled, an IRQ is generated upon 10-bit counter overflow.
The counter increases on every M2 cycle regardless of IRQ enable status. If enabled, an IRQ is generated upon 10-bit counter overflow.


==CIRAM Bank Select
==CIRAM Bank Select==
  Mask: $8073
  Mask: $8073
  Write to $8050: Select 1 KiB CIRAM bank at PPU $2000
  Write to $8050: Select 1 KiB CIRAM bank at PPU $2000

Revision as of 21:04, 15 December 2020

NES 2.0 Mapper 417 denotes the PCB of the "Fine Studio" bootleg copy of Batman: The Video Game.

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

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 counter overflow.

CIRAM Bank Select

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