fceugx/source/fceultra/boards/12in1.cpp
2016-09-17 20:43:24 -07:00

74 lines
2.2 KiB
C++

/* FCE Ultra - NES/Famicom Emulator
*
* Copyright notice for this file:
* Copyright (C) 2009 CaH4e3
*
* 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
*
* 7-in-1 Darkwing Duck, Snake, MagicBlock (PCB marked as "12 in 1")
* 12-in-1 1991 New Star Co. Ltd.
*
*/
#include "mapinc.h"
static uint8 prgchr[2], ctrl;
static SFORMAT StateRegs[] =
{
{ prgchr, 2, "REGS" },
{ &ctrl, 1, "CTRL" },
{ 0 }
};
static void Sync(void) {
uint8 bank = (ctrl & 3) << 3;
setchr4(0x0000, (prgchr[0] >> 3) | (bank << 2));
setchr4(0x1000, (prgchr[1] >> 3) | (bank << 2));
if (ctrl & 8) {
setprg16(0x8000, bank | (prgchr[0] & 6) | 0); // actually, both 0 and 1 registers used, but they will switch each PA12 transition
setprg16(0xc000, bank | (prgchr[0] & 6) | 1); // if bits are different for both registers, so they must be programmed strongly the same!
} else {
setprg16(0x8000, bank | (prgchr[0] & 7));
setprg16(0xc000, bank | 7 );
}
setmirror(((ctrl & 4) >> 2) ^ 1);
}
static DECLFW(BMC12IN1Write) {
switch (A & 0xE000) {
case 0xA000: prgchr[0] = V; Sync(); break;
case 0xC000: prgchr[1] = V; Sync(); break;
case 0xE000: ctrl = V & 0x0F; Sync(); break;
}
}
static void BMC12IN1Power(void) {
prgchr[0] = prgchr[1] = ctrl = 0;
Sync();
SetReadHandler(0x8000, 0xFFFF, CartBR);
SetWriteHandler(0x8000, 0xFFFF, BMC12IN1Write);
}
static void StateRestore(int version) {
Sync();
}
void BMC12IN1_Init(CartInfo *info) {
info->Power = BMC12IN1Power;
GameStateRestore = StateRestore;
AddExState(&StateRegs, ~0, 0, 0);
}