INES Mapper 243: Difference between revisions
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=See also= | =See also= | ||
* [https://www.flickr.com/photos/153392699@N08/sets/72157682682439086 Box, Cart, and PCB picture of ''Honey Peach''] | * [https://www.flickr.com/photos/153392699@N08/sets/72157682682439086 Box, Cart, and PCB picture of ''Honey Peach''] |
Revision as of 12:56, 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 and solder Pad ($4100, read)
Mask: $C100 D~7654 3210 --------- .... .RRD ||+- Solder pad value ++-- 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.