mappers/6.c

   1 /* FCE Ultra - NES/Famicom Emulator
   2  *
   3  * Copyright notice for this file:
   4  *  Copyright (C) 2002 Ben Parnell
   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 #define FVRAM_BANK8(A,V) {VPage[0]=VPage[1]=VPage[2]=VPage[3]=VPage[4]=VPage[5]=VPage[6]=VPage[7]=V?&MapperExRAM[(V)<<13]-(A):&CHRRAM[(V)<<13]-(A);CHRBankList[0]=((V)<<3);CHRBankList[1]=((V)<<3)+1;CHRBankList[2]=((V)<<3)+2;CHRBankList[3]=((V)<<3)+3;CHRBankList[4]=((V)<<3)+4;CHRBankList[5]=((V)<<3)+5;CHRBankList[6]=((V)<<3)+6;CHRBankList[7]=((V)<<3)+7;PPUCHRRAM=0xFF;}
  25
  26 static void FP_FASTAPASS(1) FFEIRQHook(int a)
  27 {
  28   if(IRQa)
  29   {
  30    IRQCount+=a;
  31    if(IRQCount>=0x10000)
  32    {
  33     TriggerIRQ();
  34     IRQa=0;
  35     IRQCount=0;
  36    }
  37   }
  38 }
  39
  40 DECLFW(Mapper6_write)
  41 {
  42         if(A<0x8000)
  43         {
  44                 switch(A){
  45                 case 0x42FF:MIRROR_SET((V>>4)&1);break;
  46                 case 0x42FE:onemir((V>>3)&2);break;
  47                 case 0x4501:IRQa=0;break;
  48                 case 0x4502:IRQCount&=0xFF00;IRQCount|=V;break;
  49                 case 0x4503:IRQCount&=0xFF;IRQCount|=V<<8;IRQa=1;break;
  50                 }
  51         } else {
  52         ROM_BANK16(0x8000,V>>2);
  53         FVRAM_BANK8(0x0000,V&3);
  54         }
  55 }
  56 void Mapper6_StateRestore(int version)
  57 {
  58  int x;
  59  for(x=0;x<8;x++)
  60   if(PPUCHRRAM&(1<<x))
  61   {
  62    if(CHRBankList[x]>7)
  63     VPage[x]=&MapperExRAM[(CHRBankList[x]&31)*0x400]-(x*0x400);
  64    else VPage[x]=&CHRRAM[(CHRBankList[x]&7)*0x400]-(x*0x400);
  65   }
  66 }
  67 void Mapper6_init(void)
  68 {
  69 MapIRQHook=FFEIRQHook;
  70 ROM_BANK16(0xc000,7);
  71
  72 SetWriteHandler(0x4020,0x5fff,Mapper6_write);
  73 SetWriteHandler(0x8000,0xffff,Mapper6_write);
  74 MapStateRestore=Mapper6_StateRestore;
  75 }
  76