Files
ci-libretro-fceumm/src/boards/asic_mmc2and4.c
2025-09-07 00:32:28 +02:00

118 lines
2.9 KiB
C

/* FCE Ultra - NES/Famicom Emulator
*
* Copyright notice for this file:
* Copyright (C) 2025 NewRisingSun
*
* 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
*/
#include "mapinc.h"
#include "asic_mmc2and4.h"
static void (*MMC24_cbSync)();
static uint8 MMC24_reg[6];
static uint8 MMC24_latch[2];
static SFORMAT MMC24_state[] = {
{ MMC24_reg, 6, "MC2R" },
{ MMC24_latch, 2, "MC2S" },
{ 0 }
};
static void (*MMC24_cbSync)();
void MMC24_syncWRAM (int OR) {
if (PRGsize[0x10]) setprg8r(0x10, 0x6000, OR);
}
void MMC2_syncPRG (int AND, int OR) {
setprg8(0x8000, MMC24_reg[0] &AND |OR);
setprg8(0xA000, 0xFD &AND |OR);
setprg8(0xC000, 0xFE &AND |OR);
setprg8(0xE000, 0xFF &AND |OR);
}
void MMC4_syncPRG (int AND, int OR) {
setprg16(0x8000, MMC24_reg[0] &AND |OR);
setprg16(0xC000, 0xFF &AND |OR);
}
void MMC24_syncCHR (int AND, int OR) {
setchr4(0x0000, MMC24_reg[1 +MMC24_latch[0]] &AND |OR);
setchr4(0x1000, MMC24_reg[3 +MMC24_latch[1]] &AND |OR);
}
void MMC24_syncMirror () {
setmirror(MMC24_reg[5] &1? MI_H: MI_V);
}
static void FP_FASTAPASS(1) MMC24_trapPPUAddressChange (uint32 A) {
if ((A &0x2FF0) == 0xFD0 || (A &0x2FF0) == 0xFE0) {
MMC24_latch[A >>12 &1] = A >>5 &1;
MMC24_cbSync();
}
}
DECLFW(MMC24_write) {
MMC24_reg[(A >>12) -0xA] = V;
MMC24_cbSync();
}
static void MMC24_clear () {
MMC24_reg[0] = 0; MMC24_reg[1] = 0; MMC24_reg[2] = 2; MMC24_reg[3] = 0; MMC24_reg[4] = 0; MMC24_reg[5] = 0;
MMC24_latch[0] = 0; MMC24_latch[1] = 0;
MMC24_cbSync();
}
static void MMC24_setHandlers() {
SetReadHandler (0x8000, 0xFFFF, CartBR);
SetWriteHandler(0xA000, 0xFFFF, MMC24_write);
PPU_hook = MMC24_trapPPUAddressChange;
}
static void MMC24_configure (void (*sync)()) {
MMC24_cbSync = sync;
}
void MMC24_activate (uint8 clear, void (*sync)()) {
MMC24_configure(sync);
MMC24_setHandlers();
if (clear)
MMC24_clear();
else
MMC24_cbSync();
}
void MMC24_addExState () {
AddExState(MMC24_state, ~0, 0, 0);
}
void MMC24_restore (int version) {
MMC24_cbSync();
}
void MMC24_power () {
MMC24_setHandlers();
MMC24_clear();
}
void MMC24_init (CartInfo *info, void (*sync)()) {
MMC24_addExState();
MMC24_configure(sync);
info->Power = MMC24_power;
info->Reset = MMC24_cbSync;
GameStateRestore = MMC24_restore;
}