NES 2.0 Mapper 282: Difference between revisions
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* ''1997 Super HIK 21-in-1 (JY-105)'' | * ''1997 Super HIK 21-in-1 (JY-105)'' | ||
* ''1998 Super HIK 5-in-1 (JY-114)'' | * ''1998 Super HIK 5-in-1 (JY-114)'' | ||
* ''Super 25-in-1 Final Fight (SC-128)'' | |||
Each of them have 1 MiB each of PRG-ROM and CHR-ROM. They use the [[J.Y. Company ASIC]]. Register $D003 controls 256 KiB outer banks. | Each of them have 1 MiB each of PRG-ROM and CHR-ROM. They use the [[J.Y. Company ASIC]]. Register $D003 controls 256 KiB outer banks. | ||
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7654 3210 | 7654 3210 | ||
---- ---- | ---- ---- | ||
.. | ..LM CPPc | ||
|| |||+- Select 256 KiB outer CHR-ROM bank (CHR A18), ignored if L=1 | |||
|| |++-- Select 256/512 KiB outer PRG-ROM bank | |||
|| +---- If bit 4==1: Select 512 KiB outer CHR-ROM bank | |||
|+------ 0: Ignore bit 3 | |||
| 1: Obey bit 3 | |||
+------- Select outer CHR-ROM bank size | |||
0: Mask $900x/$A00x to 256 KiB, use c | |||
1: Mask $900x/$A00x to 512 KiB, ignore c | |||
PRG ($8000-$8FFF) and CHR ($9000-$AFFF) bank select register bits that select 256 KiB banks are masked off. | PRG ($8000-$8FFF) and CHR ($9000-$AFFF) bank select register bits that select 256 KiB banks (L=0)/512 KiB banks (L=1) are masked off. | ||
For a description of all other registers, see [[J.Y. Company ASIC]]. | For a description of all other registers, see [[J.Y. Company ASIC]]. | ||
Revision as of 16:20, 26 March 2019
NES 2.0 Mapper 282 is used by at least three J.Y. multicarts:
- 1997 Super HIK 18-in-1 (JY-101)
- 1997 Super HIK 21-in-1 (JY-105)
- 1998 Super HIK 5-in-1 (JY-114)
- Super 25-in-1 Final Fight (SC-128)
Each of them have 1 MiB each of PRG-ROM and CHR-ROM. They use the J.Y. Company ASIC. Register $D003 controls 256 KiB outer banks.
Outer Bank Register ($D003)
Mask: $F003
7654 3210
---- ----
..LM CPPc
|| |||+- Select 256 KiB outer CHR-ROM bank (CHR A18), ignored if L=1
|| |++-- Select 256/512 KiB outer PRG-ROM bank
|| +---- If bit 4==1: Select 512 KiB outer CHR-ROM bank
|+------ 0: Ignore bit 3
| 1: Obey bit 3
+------- Select outer CHR-ROM bank size
0: Mask $900x/$A00x to 256 KiB, use c
1: Mask $900x/$A00x to 512 KiB, ignore c
PRG ($8000-$8FFF) and CHR ($9000-$AFFF) bank select register bits that select 256 KiB banks (L=0)/512 KiB banks (L=1) are masked off.
For a description of all other registers, see J.Y. Company ASIC.
Trivia
Some of the multicarts show different version of menu according to what $5000 is returned from the mapper (the value that is read is masked with $C0, so only bits 7 & 6 matters.):
1997 Super HIK 18-in-1 (JY-101) $00 -> 18 in 1 $40 -> 900 in 1 $80 -> 1600 in 1 $C0 -> 6000000 in 1
1997 Super HIK 21-in-1 (JY-105) $00 -> 21 in 1 $40 -> 350 in 1 $80 -> 1200 in 1 $C0 -> 7000000 in 1
