fceux/mappers/25.c

101 lines
2.8 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 K4IRQ mapbyte1[1]
#define K4sel mapbyte1[0]
static int acount=0;
static DECLFW(Mapper25_write)
{
A=(A&0xF003)|((A&0xC)>>2);
if((A&0xF000)==0xA000)
ROM_BANK8(0xA000,V);
else if(A>=0xB000 && A<=0xEFFF)
{
int x=(A&1)|((A-0xB000)>>11);
K4buf[x]&=(0xF0)>>((A&2)<<1);
K4buf[x]|=(V&0xF)<<((A&2)<<1);
VROM_BANK1(x<<10,K4buf[x]);
}
else if((A&0xF000)==0x8000)
{
if(K4sel&2)
ROM_BANK8(0xC000,V);
else
ROM_BANK8(0x8000,V);
}
else switch(A)
{
case 0x9000:switch(V&0x3)
{
case 0:MIRROR_SET(0);break;
case 1:MIRROR_SET(1);break;
case 2:onemir(0);break;
case 3:onemir(1);break;
}
break;
case 0x9001:if((K4sel&2)!=(V&2))
{
uint8 swa;
swa=PRGBankList[0];
ROM_BANK8(0x8000,PRGBankList[2]);
ROM_BANK8(0xc000,swa);
}
K4sel=V;
break;
case 0xf000:IRQLatch&=0xF0;IRQLatch|=V&0xF;break;
case 0xf002:IRQLatch&=0x0F;IRQLatch|=V<<4;break;
case 0xf001:IRQCount=IRQLatch;IRQa=V&2;K4IRQ=V&1;acount=0;X6502_IRQEnd(FCEU_IQEXT);break;
case 0xf003:IRQa=K4IRQ;X6502_IRQEnd(FCEU_IQEXT);break;
}
}
static void FP_FASTAPASS(1) KonamiIRQHook(int a)
{
// #define LCYCS ((227*2))
#define LCYCS 341
if(IRQa)
{
acount+=a*3;
// acount+=a*4;
if(acount>=LCYCS)
{
doagainbub:acount-=LCYCS;IRQCount++;
if(IRQCount&0x100)
{//acount=0;
X6502_IRQBegin(FCEU_IQEXT);IRQCount=IRQLatch;
}
if(acount>=LCYCS) goto doagainbub;
}
}
}
void Mapper25_init(void)
{
SetWriteHandler(0x8000,0xffff,Mapper25_write);
MapIRQHook=KonamiIRQHook;
}