INES Mapper 243: Difference between revisions
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NewRisingSun (talk | contribs) (No readable solder pad on SA-020A.) |
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3: Single-screen: S0 | 3: Single-screen: S0 | ||
Registers 0/1/3 are completely unused. | Registers 0/1/3 are completely unused. | ||
==Protection | ==Protection ($4100, read)== | ||
Mask: $C100 | Mask: $C100 | ||
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.... .RRR | .... .RRR | ||
+++- Inverse of previous index | +++- Inverse of previous index | ||
=Errata= | =Errata= | ||
The '''SA-150''' PCB, denoted by [[INES Mapper 150]], connects the same ASIC differently, changing the meaning of the CHR-bank-related register bits. | The '''SA-150''' PCB, denoted by [[INES Mapper 150]], connects the same ASIC differently, changing the meaning of the CHR-bank-related register bits. | ||
Revision as of 23:53, 7 December 2019
iNES Mapper 243 denotes the Sachen SA-020A circuit board. Using an eight-register ASIC with a fake "74LS374N" marking, it supports up to 128 KiB PRG-ROM, and 128 KiB of CHR-ROM. It is used for only one game, 美女拳 - Honey Peach (SA-006).
Banks
- CPU $8000-$FFFF: switchable 32 KiB PRG-ROM bank
- PPU $0000-$1FFF: switchable 8 KiB CHR-ROM bank
- Nametable mirroring: switchable H/V/L-shaped/One-screen
Registers
Register Index ($4100, write)
Mask: $C101
D~7654 3210
---------
.... .RRR
+++- Select register number (Rx)
Register Data ($4101, write)
Mask: $C101
D~7654 3210
---------
.... .RRR
+++- Register data
D~7654 3210
---------
.... ...A R2: CHR A13
.... ...C R4: CHR A14
.... ..PP R5: PRG A16..A15
.... ..DC R6: CHR A16..A15
... .MM. R7: Nametable mirroring
0: Vertical
1: Horizontal
2: L-shaped: S0-S1-S1-S1
3: Single-screen: S0
Registers 0/1/3 are completely unused.
Protection ($4100, read)
Mask: $C100
D~7654 3210
---------
.... .RRR
+++- Inverse of previous index
Errata
The SA-150 PCB, denoted by INES Mapper 150, connects the same ASIC differently, changing the meaning of the CHR-bank-related register bits.
