fceugx/source/fceultra/mappers/95.c
2008-09-02 01:55:12 +00:00

137 lines
3.0 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"
static uint8 lastA;
static uint8 DRegs[8];
static uint8 cmd;
static uint8 MirCache[8];
static SFORMAT DB_StateRegs[]={
{DRegs, 8, "DREG"},
{&cmd, 1, "CMD"},
{&lastA, 1, "LAST"},
{0}
};
static void FP_FASTAPASS(1) dragonbust_ppu(uint32 A)
{
static int last=-1;
static uint8 z;
if(A>=0x2000) return;
A>>=10;
lastA=A;
z=MirCache[A];
if(z!=last)
{
onemir(z);
last=z;
}
}
static void toot(void)
{
int x;
MirCache[0]=MirCache[1]=(DRegs[0]>>4)&1;
MirCache[2]=MirCache[3]=(DRegs[1]>>4)&1;
for(x=0;x<4;x++)
MirCache[4+x]=(DRegs[2+x]>>5)&1;
onemir(MirCache[lastA]);
}
static DECLFW(Mapper95_write)
{
switch(A&0xF001)
{
case 0x8000:
cmd = V;
break;
case 0x8001:
switch(cmd&0x07)
{
case 0: DRegs[0]=(V&0x3F)>>1;toot();V>>=1;setchr2(0x0000,V&0x1F);break;
case 1: DRegs[1]=(V&0x3F)>>1;toot();V>>=1;setchr2(0x0800,V&0x1F);break;
case 2: DRegs[2]=V&0x3F;toot();setchr1(0x1000,V&0x1F); break;
case 3: DRegs[3]=V&0x3F;toot();setchr1(0x1400,V&0x1F); break;
case 4: DRegs[4]=V&0x3F;toot();setchr1(0x1800,V&0x1F); break;
case 5: DRegs[5]=V&0x3F;toot();setchr1(0x1C00,V&0x1F); break;
case 6: DRegs[6]=V&0x3F;
setprg8(0x8000,V);
break;
case 7: DRegs[7]=V&0x3F;
setprg8(0xA000,V);
break;
}
break;
}
}
static void DBSync()
{
int x;
setchr2(0x0000,DRegs[0]);
setchr2(0x0800,DRegs[1]);
for(x=0;x<4;x++)
setchr1(0x1000+x*0x400,DRegs[2+x]);
setprg8(0x8000,DRegs[6]);
setprg8(0xa000,DRegs[7]);
toot();
}
static void DBPower(void)
{
memset(DRegs,0x3F,8);
DRegs[0]=DRegs[1]=0x1F;
DBSync();
setprg8(0xc000,0x3E);
setprg8(0xe000,0x3F);
SetReadHandler(0x8000,0xffff,CartBR);
SetWriteHandler(0x8000,0xffff,Mapper95_write);
}
static void StateRestore(int version)
{
DBSync();
}
void Mapper95_Init(CartInfo *info)
{
info->Power=DBPower;
AddExState(DB_StateRegs, ~0, 0, 0);
PPU_hook=dragonbust_ppu;
GameStateRestore=StateRestore;
}