INES Mapper 111: Difference between revisions
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Like [[iNES Mapper 030]], the specific flash used on this board is the SST39SF040. Games are expected to use the chip's self-erase and self-write abilities for game saves. | Like [[iNES Mapper 030]], the specific flash used on this board is the SST39SF040. Games are expected to use the chip's self-erase and self-write abilities for game saves. | ||
The specific hardware on this board is a [[74377]], a [[7402]], and a [[7410]]. The exact connectivity is not known, but the functions evaluated by the logic must include: | |||
* CHRRAMA14 = if (PPUA13==1) { n } else { c } | |||
* PRGROM/OE = NOT(R/W) | |||
* Latch on M2, /ROMSEL, A14, A12 high, and maybe on R/W low | |||
Information: [http://forums.nesdev.org/viewtopic.php?p=146039 Membler Industries in 2015] - forum post describing the board. | Information: [http://forums.nesdev.org/viewtopic.php?p=146039 Membler Industries in 2015] - forum post describing the board. | ||
Revision as of 19:06, 21 July 2017
Mapper 111 is used by Memblers' Cheapocabra GT-ROM 512k self-flashable board.
It is only well-defined for 512KiB PRG, 32 KiB CHR-RAM, and 4-screen nametables.
Mask: $D000
$5000: [grnc pppp]
|||| ||||
|||| ++++- Select 32 KiB PRG at CPU $8000-$FFFF
|||+------ Select 8 KiB CHR RAM at PPU $0000-$1FFF
||+------- Select 8 KiB nametable and scratch RAM at PPU $2000-$3EFF
|+-------- 0: red LED is lit, 1: off
+--------- 0: green LED is lit, 1: off
Like iNES Mapper 030, the specific flash used on this board is the SST39SF040. Games are expected to use the chip's self-erase and self-write abilities for game saves.
The specific hardware on this board is a 74377, a 7402, and a 7410. The exact connectivity is not known, but the functions evaluated by the logic must include:
- CHRRAMA14 = if (PPUA13==1) { n } else { c }
- PRGROM/OE = NOT(R/W)
- Latch on M2, /ROMSEL, A14, A12 high, and maybe on R/W low
Information: Membler Industries in 2015 - forum post describing the board.
