Files
ci-libretro-fceumm/src/boards/237.c
2019-07-02 09:37:00 +08:00

92 lines
2.3 KiB
C

/* FCEUmm - NES/Famicom Emulator
*
* Copyright notice for this file:
* Copyright (C) 2019 Libretro Team
*
* 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
*/
/* Mapper 237 - "Teletubbies / Y2K" 420-in-1 pirate multicart.
* Dipswitch settings:
* 0: 42-in-1
* 1: 5,000-in-1
* 2: 420-in-1
* 3: 10,000,000-in-1 (lol)
*/
#include "mapinc.h"
static uint8 reg[2];
static uint8 dipswitch;
static SFORMAT StateRegs[] =
{
{ &reg[0], 1, "REG0" },
{ &reg[1], 1, "REG1" },
{ &dipswitch, 1, "DPSW" },
{ 0 }
};
static void Sync(void) {
uint8 bank = (reg[1] & 0x07);
uint8 base = (reg[1] & 0x18) | ((reg[0] & 0x04) << 3);
uint8 mode = (reg[1] & 0xC0) >> 6;
setchr8(0);
setprg16(0x8000, base | (bank & ~(mode & 1)));
setprg16(0xC000, base | ((mode & 0x02) ? (bank | (mode & 0x01)) : 0x07));
setmirror(((reg[1] & 0x20) >> 5) ^ 1);
}
static DECLFW(M237Write) {
if (!(reg[0] & 0x02)) {
reg[0] = A & 0x0F;
reg[1] = (reg[1] & 0x07) | (V & 0xF8);
}
reg[1] = (reg[1] & 0xF8) | (V & 0x07);
Sync();
}
static DECLFR(M237Read) {
if (!(reg[0] & 0x02) && (reg[0] & 0x01))
return dipswitch;
return CartBR(A);
}
static void M237Power(void) {
Sync();
SetReadHandler (0x8000, 0xFFFF, M237Read);
SetWriteHandler(0x8000, 0xFFFF, M237Write);
}
static void M237Reset(void) {
reg[0] = reg[1] = 0;
Sync();
}
static void StateRestore(int version) {
Sync();
}
void Mapper237_Init(CartInfo *info) {
dipswitch = 0;
if ((info->CRC32) == 0x272709b9) /* Teletubbies Y2K (420-in-1) */
dipswitch = 2;
info->Power = M237Power;
info->Reset = M237Reset;
GameStateRestore = StateRestore;
AddExState(&StateRegs, ~0, 0, 0);
}