Files
ci-libretro-fceumm/src/boards/116.c
2025-09-12 21:59:27 +02:00

146 lines
4.0 KiB
C

/* FCE Ultra - NES/Famicom Emulator
*
* Copyright notice for this file:
* Copyright (C) 2023
*
* 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_mmc1.h"
#include "asic_mmc3.h"
#include "asic_vrc2and4.h"
static uint8 submapper;
static uint8 reg;
static uint8 init; /* Games switch between ASICs expecting registers to keep their value, so initialize each ASIC only on the first switch and use this bitfield to track it */
static uint8 game;
static SFORMAT stateRegs[] = {
{ &reg, 1, "MODE" },
{ &init, 1, "INIT" },
{ 0 },
};
static SFORMAT stateRegsMulti[] = {
{ &game, 1, "GAME" },
{ 0 },
};
static void sync (void) {
int prgAND, chrAND, prgOR, chrOR;
if (submapper == 3) { /* First game is 256K+256K, the others 128K+128K */
prgAND = game? 0x0F: 0x1F;
chrAND = game? 0x7F: 0xFF;
prgOR = game <<4 &~prgAND;
chrOR = game <<7 &~chrAND;
} else {
prgAND = 0x3F;
chrAND = 0xFF;
prgOR = 0x00 &~prgAND;
chrOR = reg <<6 &0x100 &~chrAND;
}
if (reg &0x02) {
prgAND >>= 1;
prgOR >>= 1;
chrAND >>= 2;
chrOR >>= 2;
MMC1_syncPRG(prgAND, prgOR);
MMC1_syncCHR(chrAND, chrOR);
MMC1_syncMirror();
} else
if (reg &0x01) {
MMC3_syncPRG(prgAND, prgOR);
MMC3_syncCHR(chrAND, chrOR);
MMC3_syncMirror();
} else {
VRC24_syncPRG(prgAND, prgOR);
VRC24_syncCHR(chrAND, chrOR);
VRC24_syncMirror();
}
}
int Huang2_getPRGBank (uint8 bank) {
return MMC1_getPRGBank(bank) >>1;
}
static void applyMode (uint8 clear) {
PPU_hook = NULL;
MapIRQHook = NULL;
GameHBIRQHook = NULL;
if (reg &0x02) {
MMC1_activate(clear && init &1, sync, MMC1_TYPE_MMC1B, submapper == 2? Huang2_getPRGBank: NULL, NULL, NULL, NULL);
if (submapper != 1) MMC1_writeReg(0x8000, 0x80);
init &= ~1;
} else
if (reg &0x01) {
MMC3_activate(clear && init &2, sync, MMC3_TYPE_AX5202P, NULL, NULL, NULL, NULL);
init &= ~2;
} else {
VRC2_activate(clear && init &4, sync, 0x01, 0x02, NULL, NULL, NULL, NULL);
if (init &4) { /* The earlier version of Somari needs specific VRC2 CHR register initialization */
VRC24_writeReg(0xB000, 0xFF); VRC24_writeReg(0xB001, 0xFF); VRC24_writeReg(0xB002, 0xFF); VRC24_writeReg(0xB003, 0xFF);
VRC24_writeReg(0xC000, 0xFF); VRC24_writeReg(0xC001, 0xFF); VRC24_writeReg(0xC002, 0xFF); VRC24_writeReg(0xC003, 0xFF);
VRC24_writeReg(0xD000, 0xFF); VRC24_writeReg(0xD001, 0xFF); VRC24_writeReg(0xD002, 0xFF); VRC24_writeReg(0xD003, 0xFF);
VRC24_writeReg(0xE000, 0xFF); VRC24_writeReg(0xE001, 0xFF); VRC24_writeReg(0xE002, 0xFF); VRC24_writeReg(0xE003, 0xFF);
init &= ~4;
}
}
}
static DECLFW (writeReg) {
if (A &0x100) {
uint8 previousReg = reg;
reg = V;
if ((previousReg ^V) &3)
applyMode(1);
else
sync();
}
}
static void reset (void) {
reg = 1;
init = 7;
if (++game == 1) ++game; /* First game is twice as large */
if (game >= ROM_size /8) game = 0;
applyMode(1);
}
static void power (void) {
reg = 1;
init = 7;
game = 0;
SetReadHandler(0x8000, 0xFFFF, CartBR);
SetWriteHandler(0x4020, 0x5FFF, writeReg);
applyMode(1);
}
static void restore (int version) {
applyMode(0);
}
void UNLSL12_Init (CartInfo *info) {
submapper = info->submapper;
MMC1_addExState();
MMC3_addExState();
VRC24_addExState();
info->Reset = reset;
info->Power = power;
GameStateRestore = restore;
AddExState(stateRegs, ~0, 0, 0);
if (submapper == 3) AddExState(stateRegsMulti, ~0, 0, 0);
}