Files
ci-libretro-fceumm/src/boards/452.c
2022-08-02 17:20:02 +02:00

99 lines
2.7 KiB
C

/* FCE Ultra - NES/Famicom Emulator
*
* Copyright notice for this file:
* Copyright (C) 2012 CaH4e3
* Copyright (C) 2002 Xodnizel
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
*/
/* DS-9-27. Absolutely insane PCB that overlays 8 KiB of WRAM into a selectable position between $8000 and $E000. */
#include "mapinc.h"
static uint8 *WRAM;
static uint32 WRAMSIZE;
static uint16 latch[2];
static void Mapper452_Sync(void) {
uint8 wramBank = latch[1] >>3 &6 |8;
if (latch[1] &2) {
setprg8(0x8000, latch[0] >>1);
setprg8(0xA000, latch[0] >>1);
setprg8(0xC000, latch[0] >>1);
setprg8(0xE000, latch[0] >>1);
setprg8r(0x10, (wramBank ^4) <<12, 0);
} else
if (latch[1] &8) {
setprg8(0x8000, latch[0] >>1 &~1 |0);
setprg8(0xA000, latch[0] >>1 &~1 |1);
setprg8(0xC000, latch[0] >>1 &~1 |2);
setprg8(0xE000, latch[0] >>1 &~1 |3 | latch[1] &4 | (latch[1] &0x04 && latch[1] &0x40? 8: 0));
} else {
setprg16(0x8000, latch[0] >>2);
setprg16(0xC000, 0);
}
setprg8r(0x10, wramBank <<12, 0);
setchr8(0);
setmirror(latch [1] &1 ^1);
}
static DECLFW(Mapper452_WriteLatch) {
latch[0] =A &0xFFF;
latch[1] =V;
Mapper452_Sync();
/* Do not relay to CartBW, as RAM mapped to locations other than $8000-$DFFF are not write-enabled. */
}
static void Mapper452_Reset(void) {
latch[0] =latch[1] =0;
Mapper452_Sync();
}
static void Mapper452_Power(void) {
latch[0] =latch[1] =0;
Mapper452_Sync();
SetReadHandler(0x8000, 0xFFFF, CartBR);
SetWriteHandler(0x8000, 0xDFFF, Mapper452_WriteLatch);
SetWriteHandler(0xE000, 0xFFFF, CartBW);
FCEU_CheatAddRAM(WRAMSIZE >> 10, 0x6000, WRAM);
}
static void Mapper452_Close(void) {
if (WRAM)
FCEU_gfree(WRAM);
WRAM = NULL;
}
static void StateRestore(int version) {
Mapper452_Sync();
}
void Mapper452_Init(CartInfo *info) {
info->Reset = Mapper452_Reset;
info->Power = Mapper452_Power;
info->Close = Mapper452_Close;
GameStateRestore = StateRestore;
WRAMSIZE = 8192;
WRAM = (uint8*) FCEU_gmalloc(WRAMSIZE);
SetupCartPRGMapping(0x10, WRAM, WRAMSIZE, 1);
AddExState(WRAM, WRAMSIZE, 0, "WRAM");
AddExState(&latch, 4, 0, "LATC");
}