fceux/mappers/18.cpp

81 lines
2.2 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 K4buf mapbyte2
#define K4buf2 mapbyte3
void FP_FASTAPASS(1) JalecoIRQHook(int a)
{
if(IRQa && IRQCount)
{
IRQCount-=a;
if(IRQCount<=0)
{
X6502_IRQBegin(FCEU_IQEXT);
IRQCount=0;
IRQa=0;
}
}
}
DECLFW(Mapper18_write)
{
A&=0xF003;
if(A>=0x8000 && A<=0x9001)
{
int x=((A>>1)&1)|((A-0x8000)>>11);
K4buf2[x]&=(0xF0)>>((A&1)<<2);
K4buf2[x]|=(V&0xF)<<((A&1)<<2);
ROM_BANK8(0x8000+(x<<13),K4buf2[x]);
}
else if(A>=0xa000 && A<=0xd003)
{
int x=((A>>1)&1)|((A-0xA000)>>11);
K4buf[x]&=(0xF0)>>((A&1)<<2);
K4buf[x]|=(V&0xF)<<((A&1)<<2);
VROM_BANK1(x<<10,K4buf[x]);
}
else switch(A)
{
case 0xe000:IRQLatch&=0xFFF0;IRQLatch|=(V&0x0f);break;
case 0xe001:IRQLatch&=0xFF0F;IRQLatch|=(V&0x0f)<<4;break;
case 0xe002:IRQLatch&=0xF0FF;IRQLatch|=(V&0x0f)<<8;break;
case 0xe003:IRQLatch&=0x0FFF;IRQLatch|=(V&0x0f)<<12;break;
case 0xf000:IRQCount=IRQLatch;
break;
case 0xf001:IRQa=V&1;
X6502_IRQEnd(FCEU_IQEXT);
break;
case 0xf002:MIRROR_SET2(V&1);
if(V&2) onemir(0);
break;
}
}
void Mapper18_init(void)
{
SetWriteHandler(0x8000,0xffff,Mapper18_write);
MapIRQHook=JalecoIRQHook;
}