NES 2.0 Mapper 554: Difference between revisions

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(Created page with "{{DEFAULTSORT:554}}Category:FDS conversion mappers '''NES 2.0 Mapper 554''' denotes the Kaiser '''KS-7010''' circuit board, used for one of several cartridge conversions o...")
 
(KS-201 pinout redirection)
Line 24: Line 24:


=ASIC connection=
=ASIC connection=
KS-201 connected
See: [[KS-201 pinout]]
pin#    to
  1      CPU M2
  2      CPU A1
  3      CPU A2
  4      CPU A3
  5      CPU A4
  6      CPU A5
  7      CPU A6
  8      CPU A7
  9      CPU A8
  10    CPU A9
  11    CPU A10
  12    CPU A11
  13    CPU A12
  14    GND
  15    CPU A13
  16    CPU A14
  17    /CE
  18    VCC
  19    PRG ROM /CE
  20    CHR ROM A16
  21    CHR ROM A15
  22    CHR ROM A14
  23    CHR ROM A13
  24    PRG ROM A16
  25    PRG ROM A15
  26    PRG ROM A14
  27    PRG ROM A13
  28    VCC

Revision as of 22:58, 20 May 2020

NES 2.0 Mapper 554 denotes the Kaiser KS-7010 circuit board, used for one of several cartridge conversions of the FDS version of 悪魔城 Dracula, the Japanese version of Castlevania. Bankswitching is unusual in being triggered entirely through reads from "magic" addresses. The board mounts 128 KiB PRG-ROM, 128 KiB CHR-ROM, a KS-201 ASIC and a 74'32.

Banks

  • CPU $6000-$7FFF: Switchable 8 KiB PRG-ROM bank
  • CPU $8000-$9FFF: Fixed 8 KiB PRG-ROM bank #10
  • CPU $A000-$BFFF: Fixed 8 KiB PRG-ROM bank #11
  • CPU $C000-$DFFF: Fixed 8 KiB PRG-ROM bank #6
  • CPU $E000-$FFFF: Fixed 8 KiB PRG-ROM bank #7
  • PPU $0000-$1FFF: Switchable 8 KiB CHR-ROM bank
  • Nametable mirroring: hard-wired (to vertical)

Bankswitching Reads

The 8 KiB PRG-ROM bank at $6000, and the 8 KiB CHR-ROM bank, are both switched to the same bank number whenever certain addresses are read from.

A~FEDC BA98 7654 3210
  -------------------
  .??? ???? ??DC BA1.
              ++-++--- PRG/CHR A16..13

The exact address mask is not known; the following addresses have been verified to trigger a bankswitch, and are used by the game:

  • CAB6-CAD6
  • EBE2, EE32
  • FFFC

ASIC connection

See: KS-201 pinout