NES 2.0 Mapper 529: Difference between revisions

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{{DEFAULTSORT:529}}[[Category:Mappers with cycle IRQs]]NES 2.0 Mapper 529 is used for another bootleg version of ''Datach Dragon Ball Z''. It's a [[VRC4]] clone (A2/A3, VRC4e) with PRG-ROM being selected differently: The $800x register has no effect, while the $A00x register selects a 16 KiB PRG-ROM bank. Its UNIF board name is '''UNL-T-230'''.
{{DEFAULTSORT:529}}[[Category:Mappers with cycle IRQs]]'''NES 2.0 Mapper 529''' denotes the '''YY0807''', '''J-2148''' and '''T-230''' PCBs, used for particular bootlegs version of ''Datach Dragon Ball Z'' ('''T-230''' PCB, with CHR-RAM) and ''Dragon Ball Z Gaiden'' ('''YY-0807''' PCB, with CHR-ROM). It's a [[VRC4]] clone (A2/A3, VRC4e) connected such that the $800x register has no effect, and the $A00x register selects a 16 KiB PRG-ROM bank, similar to the games' original Bandai mappers. Its UNIF board name is '''UNL-T-230'''.
 
Similarly to the Bandai mappers, it also supports saving data to serial EEPROM. The presence of EEPROM is denoted via the NES 2.0 header's PRG-NVRAM field indicating 256 byte of non-volatile save data. Unlike the original Bandai FCG boards that used an I²C interface, the bootleg variants use a 93C56 EEPROM via a Microwire interface, operated using the following registers:
 
==Read Microwire Interface ($5000, read)==
Mask: $F000
D~[.... ...D]
            +- Serial Data Output from the 93C56 EEPROM
 
==Write Microwrite Interface ($8800, write)==
Mask: $8800
D~[.... .ECD]
          ||+- Serial Data Input to 93C56 EEPROM
          |+-- Serial Clock to 93C56 EEPROM
          +--- Chip Select to 93C56 EEPROM
 
This register's address range overrides the VRC4's. The game writes to the $FFFx address range to operate this register.
 
The 93C56's EEPROM's org pin is tied to Vcc, indicating a 16-bit word length.

Revision as of 23:49, 19 February 2022

NES 2.0 Mapper 529 denotes the YY0807, J-2148 and T-230 PCBs, used for particular bootlegs version of Datach Dragon Ball Z (T-230 PCB, with CHR-RAM) and Dragon Ball Z Gaiden (YY-0807 PCB, with CHR-ROM). It's a VRC4 clone (A2/A3, VRC4e) connected such that the $800x register has no effect, and the $A00x register selects a 16 KiB PRG-ROM bank, similar to the games' original Bandai mappers. Its UNIF board name is UNL-T-230.

Similarly to the Bandai mappers, it also supports saving data to serial EEPROM. The presence of EEPROM is denoted via the NES 2.0 header's PRG-NVRAM field indicating 256 byte of non-volatile save data. Unlike the original Bandai FCG boards that used an I²C interface, the bootleg variants use a 93C56 EEPROM via a Microwire interface, operated using the following registers:

Read Microwire Interface ($5000, read)

Mask: $F000

D~[.... ...D]
           +- Serial Data Output from the 93C56 EEPROM

Write Microwrite Interface ($8800, write)

Mask: $8800

D~[.... .ECD]
         ||+- Serial Data Input to 93C56 EEPROM
         |+-- Serial Clock to 93C56 EEPROM
         +--- Chip Select to 93C56 EEPROM

This register's address range overrides the VRC4's. The game writes to the $FFFx address range to operate this register.

The 93C56's EEPROM's org pin is tied to Vcc, indicating a 16-bit word length.