mappers/6.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  * FFE
  21  *
  22  */
  23
  24 #include "mapinc.h"
  25
  26 static uint8 FFEmode;
  27
  28 #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;}
  29
  30 static void FP_FASTAPASS(1) FFEIRQHook(int a)
  31 {
  32   if(IRQa)
  33   {
  34    IRQCount+=a;
  35    if(IRQCount>=0x10000)
  36    {
  37     X6502_IRQBegin(FCEU_IQEXT);
  38     IRQa=0;
  39     IRQCount=0;
  40    }
  41   }
  42 }
  43
  44 DECLFW(Mapper6_write)
  45 {
  46         if(A<0x8000)
  47         {
  48                 switch(A){
  49                 case 0x42FF:MIRROR_SET((V>>4)&1);break;
  50                 case 0x42FE:onemir((V>>3)&2); FFEmode=V&0x80;break;
  51                 case 0x4501:IRQa=0;X6502_IRQEnd(FCEU_IQEXT);break;
  52                 case 0x4502:IRQCount&=0xFF00;IRQCount|=V;break;
  53                 case 0x4503:IRQCount&=0xFF;IRQCount|=V<<8;IRQa=1;break;
  54                 }
  55         } else {
  56          switch (FFEmode)
  57          {
  58            case 0x80:  setchr8(V); break;
  59            default: ROM_BANK16(0x8000,V>>2);
  60                     FVRAM_BANK8(0x0000,V&3);
  61          }
  62         }
  63 }
  64 void Mapper6_StateRestore(int version)
  65 {
  66  int x;
  67  for(x=0;x<8;x++)
  68   if(PPUCHRRAM&(1<<x))
  69   {
  70    if(CHRBankList[x]>7)
  71     VPage[x]=&MapperExRAM[(CHRBankList[x]&31)*0x400]-(x*0x400);
  72    else VPage[x]=&CHRRAM[(CHRBankList[x]&7)*0x400]-(x*0x400);
  73   }
  74 }
  75 void Mapper6_init(void)
  76 {
  77 MapIRQHook=FFEIRQHook;
  78 ROM_BANK16(0xc000,7);
  79
  80 SetWriteHandler(0x4020,0x5fff,Mapper6_write);
  81 SetWriteHandler(0x8000,0xffff,Mapper6_write);
  82 MapStateRestore=Mapper6_StateRestore;
  83 }