fceugx/source/fceultra/mappers/67.cpp
2009-07-17 17:27:04 +00:00

79 lines
1.9 KiB
C++

/* FCE Ultra - NES/Famicom Emulator
*
* Copyright notice for this file:
* Copyright (C) 2002 Xodnizel
*
* 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., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*/
#include "mapinc.h"
#define suntoggle mapbyte1[0]
static DECLFW(Mapper67_write)
{
A&=0xF800;
if((A&0x800) && A<=0xb800)
{
VROM_BANK2((A-0x8800)>>1,V);
}
else switch(A)
{
case 0xc800:
case 0xc000:if(!suntoggle)
{
IRQCount&=0xFF;
IRQCount|=V<<8;
}
else
{
IRQCount&=0xFF00;
IRQCount|=V;
}
suntoggle^=1;
break;
case 0xd800:suntoggle=0;IRQa=V&0x10;X6502_IRQEnd(FCEU_IQEXT);break;
case 0xe800:switch(V&3)
{
case 0:MIRROR_SET2(1);break;
case 1:MIRROR_SET2(0);break;
case 2:onemir(0);break;
case 3:onemir(1);break;
}
break;
case 0xf800:ROM_BANK16(0x8000,V);break;
}
}
static void SunIRQHook(int a)
{
if(IRQa)
{
IRQCount-=a;
if(IRQCount<=0)
{
X6502_IRQBegin(FCEU_IQEXT);
IRQa=0;
IRQCount=0xFFFF;
}
}
}
void Mapper67_init(void)
{
SetWriteHandler(0x8000,0xffff,Mapper67_write);
MapIRQHook=SunIRQHook;
}