mappers/17.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
  24
  25 static void FP_FASTAPASS(1) FFEIRQHook(int a)
  26 {
  27   if(IRQa)
  28   {
  29    IRQCount+=a;
  30    if(IRQCount>=0x10000)
  31    {
  32     X6502_IRQBegin(FCEU_IQEXT);
  33     IRQa=0;
  34     IRQCount=0;
  35    }
  36   }
  37 }
  38
  39
  40 DECLFW(Mapper17_write)
  41 {
  42         switch(A){
  43         default:
  44                    break;
  45         case 0x42FE:
  46                    onemir((V>>4)&1);
  47                    break;
  48         case 0x42FF:
  49                    MIRROR_SET((V>>4)&1);
  50                    break;
  51         case 0x4501:IRQa=0;X6502_IRQEnd(FCEU_IQEXT);break;
  52         case 0x4502:IRQCount&=0xFF00;IRQCount|=V;break;
  53         case 0x4503:IRQCount&=0x00FF;IRQCount|=V<<8;IRQa=1;break;
  54         case 0x4504: ROM_BANK8(0x8000,V);break;
  55         case 0x4505: ROM_BANK8(0xA000,V);break;
  56         case 0x4506: ROM_BANK8(0xC000,V);break;
  57         case 0x4507: ROM_BANK8(0xE000,V);break;
  58         case 0x4510: VROM_BANK1(0x0000,V);break;
  59         case 0x4511: VROM_BANK1(0x0400,V);break;
  60         case 0x4512: VROM_BANK1(0x0800,V);break;
  61         case 0x4513: VROM_BANK1(0x0C00,V);break;
  62         case 0x4514: VROM_BANK1(0x1000,V);break;
  63         case 0x4515: VROM_BANK1(0x1400,V);break;
  64         case 0x4516: VROM_BANK1(0x1800,V);break;
  65         case 0x4517: VROM_BANK1(0x1C00,V);break;
  66         }
  67 }
  68
  69 void Mapper17_init(void)
  70 {
  71 MapIRQHook=FFEIRQHook;
  72 SetWriteHandler(0x4020,0x5fff,Mapper17_write);
  73 }