mappers/64.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 #define cmd   mapbyte1[0]
  24 #define mir   mapbyte1[1]
  25 #define rmode mapbyte1[2]
  26 #define regsl mapbyte2
  27 #define regsh mapbyte3
  28
  29 static void RAMBO1_hb(void)
  30 {
  31       rmode=0;
  32       if(IRQCount>=0)
  33       {
  34         IRQCount--;
  35         if(IRQCount<0)
  36         {
  37          if(IRQa)
  38          {
  39 //          printf("IRQ: %d\n",scanline);
  40             rmode = 1;
  41             X6502_IRQBegin(FCEU_IQEXT);
  42          }
  43         }
  44       }
  45 }
  46
  47 static void Synco(void)
  48 {
  49  int x;
  50
  51  if(cmd&0x20)
  52  {
  53   setchr1(0x0000,regsl[0]);
  54   setchr1(0x0800,regsl[1]);
  55   setchr1(0x0400,regsh[0]);
  56   setchr1(0x0c00,regsh[1]);
  57  }
  58  else
  59  {
  60   setchr2(0x0000,regsl[0]>>1);
  61   setchr2(0x0800,regsl[1]>>1);
  62  }
  63
  64  for(x=0;x<4;x++)
  65   setchr1(0x1000+x*0x400,regsl[2+x]);
  66
  67  setprg8(0x8000,regsl[6]);
  68  setprg8(0xA000,regsl[7]);
  69
  70  setprg8(0xC000,regsh[7]);
  71 }
  72
  73
  74 static DECLFW(RAMBO1_write)
  75 {
  76  //if(A>=0xC000 && A<=0xFFFF) printf("$%04x:$%02x, %d, %d\n",A,V,scanline,timestamp);
  77  switch(A&0xF001)
  78  {
  79         case 0xa000:mir=V&1;
  80                     setmirror(mir^1);
  81                     break;
  82         case 0x8000:cmd = V;
  83                     break;
  84         case 0x8001:
  85                     if((cmd&15)<8)
  86                      regsl[cmd&7]=V;
  87                     else
  88                      regsh[cmd&7]=V;
  89                     Synco();
  90                     break;
  91         case 0xc000:IRQLatch=V;
  92                     if(rmode==1)
  93                      {
  94                       IRQCount=IRQLatch;
  95                      }
  96                     break;
  97         case 0xc001:rmode=1;
  98                     IRQCount=IRQLatch;
  99                     break;
 100         case 0xE000:IRQa=0;X6502_IRQEnd(FCEU_IQEXT);
 101                     if(rmode==1)
 102                      {IRQCount=IRQLatch;}
 103                     break;
 104         case 0xE001:IRQa=1;
 105                     if(rmode==1)
 106                      {IRQCount=IRQLatch;}
 107                     break;
 108   }
 109 }
 110
 111 static void RAMBO1_Restore(int version)
 112 {
 113  if(version<74)
 114  {
 115   int x;
 116
 117   x=mapbyte1[1];        // was MMC3_cmd
 118   cmd=x;
 119
 120   regsl[0]=CHRBankList[0];
 121   regsl[1]=CHRBankList[2];
 122   regsh[0]=CHRBankList[1];
 123   regsh[1]=CHRBankList[3];
 124
 125   for(x=0;x<4;x++)
 126    regsl[2+x]=CHRBankList[4+x];
 127
 128   regsl[6]=PRGBankList[0];
 129   regsl[7]=PRGBankList[1];
 130   regsh[7]=PRGBankList[2];
 131   mir=Mirroring^1;
 132  }
 133  Synco();
 134  setmirror(mir^1);
 135 }
 136
 137 void Mapper64_init(void)
 138 {
 139         int x;
 140
 141         for(x=0;x<8;x++)
 142          regsl[x]=regsh[x]=~0;
 143         cmd=0;
 144         mir=0;
 145         setmirror(1);
 146         Synco();
 147         GameHBIRQHook=RAMBO1_hb;
 148         GameStateRestore=RAMBO1_Restore;
 149         SetWriteHandler(0x8000,0xffff,RAMBO1_write);
 150 }