mappers/33.c

   1 /* FCE Ultra - NES/Famicom Emulator
   2  *
   3  * Copyright notice for this file:
   4  *  Copyright (C) 2002 Xodnizel
   5  *
   6  * This program is free software; you can redistribute it and/or modify
   7  * it under the terms of the GNU General Public License as published by
   8  * the Free Software Foundation; either version 2 of the License, or
   9  * (at your option) any later version.
  10  *
  11  * This program is distributed in the hope that it will be useful,
  12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14  * GNU General Public License for more details.
  15  *
  16  * You should have received a copy of the GNU General Public License
  17  * along with this program; if not, write to the Free Software
  18  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
  19  */
  20
  21 #include "mapinc.h"
  22
  23 static int is48;
  24
  25 static DECLFW(Mapper33_write)
  26 {
  27         //printf("%04x:%02x, %d\n",A,V,scanline);
  28
  29         A&=0xF003;
  30         if(A>=0xA000 && A<=0xA003)
  31          VROM_BANK1(0x1000+((A&3)<<10),V);
  32         else switch(A)
  33         {
  34           case 0x8000:if(!is48) MIRROR_SET((V>>6)&1);
  35                      ROM_BANK8(0x8000,V);
  36                      break;
  37          case 0x8001:ROM_BANK8(0xA000,V); break;
  38          case 0x8002:VROM_BANK2(0x0000,V);break;
  39          case 0x8003:VROM_BANK2(0x0800,V);break;
  40         }
  41 }
  42
  43 static DECLFW(Mapper48_HiWrite)
  44 {
  45         switch(A&0xF003)
  46         {
  47          case 0xc000:IRQLatch=V;break;
  48          case 0xc001:IRQCount=IRQLatch;break;
  49          case 0xc003:IRQa=0;X6502_IRQEnd(FCEU_IQEXT);break;
  50          case 0xc002:IRQa=1;break;
  51          case 0xe000:MIRROR_SET((V>>6)&1);break;
  52         }
  53 }
  54
  55 static void heho(void)
  56 {
  57  if(IRQa)
  58  {
  59    IRQCount++;
  60    if(IRQCount==0x100)
  61    {
  62     X6502_IRQBegin(FCEU_IQEXT);
  63     IRQa=0;
  64    }
  65  }
  66 }
  67
  68 void Mapper33_init(void)
  69 {
  70         SetWriteHandler(0x8000,0xffff,Mapper33_write);
  71         is48=0;
  72 }
  73
  74 void Mapper48_init(void)
  75 {
  76         SetWriteHandler(0x8000,0xbfff,Mapper33_write);
  77         SetWriteHandler(0xc000,0xffff,Mapper48_HiWrite);
  78         GameHBIRQHook=heho;
  79         is48=1;
  80 }