INES Mapper 190
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This mapper was assigned by Kevtris for a newly-dumped game from 1992: Magic Kid GooGoo
Here's a page discussing it: http://forums.lostlevels.org/viewtopic.php?p=35234
Mednafen supported it with http://forum.fobby.net/index.php?t=msg&th=1483
FCEUX supported it with https://sourceforge.net/p/fceultra/code/3334/
Finally, I will attach Kevtris's notes on the mapper:
Magic Kid GooGoo ---------------- 012517 Kevtris I have assigned this game mapper 190. Fortunately the mapper is fairly simple, being composed of two 74LS670 4*4 register file chips, a PAL16R4, some pullup resistors, two ROMs and an 8K WRAM. The mapper is fairly straight forward, but kind of weird. PRG switching: -------------- There's 16 16K PRG ROM banks, but a combination of address and data lines are used to select it. C000-FFFF is set to the *first* bank of ROM at all times (vs. the more common last bank of ROM). 8000-BFFF is selectable by writing to either 8000-9FFF or C000-DFFF. Writing to 8000-9FFF will select bank 0-7 depending on D0-D2. Writing to C000-DFFF will select bank 8-15 depending on D0-D2. So the 4 bank bits are formed like so: A14, D2, D1, D0 (highest bit to lowest bit) I don't know why they did it this way but they did. There is also 8K of RAM mapped in at 6000-7FFF. This RAM is always enabled and is not battery backed. CHR Switching: -------------- CHR is composed of 4 2K banks at 0000-07FF, 0800-0FFF, 1000-17FF, 1800-1FFF. Writing to A000 selects the bank at 0000-07FF in PPU space, A001 selects the bank at 0800-0FFF A002 selects the bank at 1000-17FF A003 selects the bank at 1800-1FFF Only A0, A1, A13, 14, and 15 are used to select the CHR bank and match the following mask: 101x xxxx xxxx xxbb b = CHR bank # to change. This means that A000, A004, A008, A00C, ... BFF8, BFFC all set the first 2K CHR bank.