Files
ci-libretro-fceumm/src/boards/518.c
2025-09-17 19:20:54 +02:00

97 lines
2.2 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 "cartram.h"
static uint8 reg[2];
static uint8 chr;
static void sync () {
setprg8r(0x10, 0x6000, 0);
if (reg[1] &0x04)
setprg32(0x8000, reg[0]);
else {
setprg16(0x8000, reg[0]);
setprg16(0xC000, 0);
}
setchr4(0x0000, reg[1] &0x02? chr: 0);
setchr4(0x1000, 1);
setmirror(reg[1] &0x01? MI_H: MI_V);
}
static void FP_FASTAPASS(1) trapPPUAddressChange (uint32 A) {
if (A &0x2000 && (A &0x23C0) < 0x23C0) {
chr = A >>(10 +(reg[1] &0x01? 1: 0)) &1;
setchr4(0x0000, reg[1] &0x02? chr: 0);
}
}
static DECLFR (readReg) {
switch(A >>8 &7) {
case 3: /* LPC state */
return 0x8F;
case 6: /* FDC */
return 0x00;
default:
return X.DB;
}
}
static DECLFW (writeReg) {
switch(A >>8 &7) {
case 0: case 2:
reg[A >>9 &1] = V;
sync();
break;
case 3: /* LPC data */
break;
case 5: /* FDC */
break;
}
}
static void reset () {
reg[0] = reg[1] = chr = 0;
sync();
}
static void power () {
SetReadHandler(0x5000, 0x5FFF, readReg);
SetReadHandler(0x6000, 0xFFFF, CartBR);
SetWriteHandler(0x5000, 0x5FFF, writeReg);
SetWriteHandler(0x6000, 0xFFFF, CartBW);
reset();
}
static void restore (int version) {
sync();
}
void Mapper518_Init (CartInfo *info) {
WRAM_init(info, 8);
info->Power = power;
info->Reset = reset;
GameStateRestore = restore;
PPU_hook = trapPPUAddressChange;
AddExState(reg, 2, 0, "REGS");
AddExState(&chr, 1, 0, "CHRB");
}