mappers/83.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 /*void Mapper83_init(void)
  25 {
  26
  27 }
  28 */
  29 static void FP_FASTAPASS(1) m83IRQHook(int a)
  30 {
  31   if(IRQa)
  32   {
  33    IRQCount-=a;
  34    if(IRQCount<0)
  35    {
  36     X6502_IRQBegin(FCEU_IQEXT);
  37     IRQa=0;
  38     IRQCount=0xFFFF;
  39    }
  40   }
  41 }
  42
  43 static DECLFW(wrlow)
  44 {
  45  mapbyte4[A&3]=V;
  46 }
  47
  48 static DECLFR(rdlow)
  49 {
  50  return mapbyte4[A&3];
  51 }
  52
  53 static void m83prg(void)
  54 {
  55   ROM_BANK16(0x8000,(mapbyte1[0]&0x3F));
  56   ROM_BANK16(0xC000,(mapbyte1[0]&0x30)|0xF);
  57 }
  58
  59 static void m83chr(void)
  60 {
  61   int x;
  62   for(x=0;x<8;x++)
  63    VROM_BANK1(x*0x400,mapbyte2[x]|((mapbyte1[0]&0x30)<<4));
  64 }
  65
  66 static DECLFW(Mapper83_write)
  67 {
  68  //printf("$%04x:$%02x\n",A,V);
  69  switch(A)
  70  {
  71   case 0x8000:
  72   case 0xB000:
  73   case 0xB0FF:
  74   case 0xB1FF:
  75        {
  76         mapbyte1[0]=V;
  77         m83prg();
  78         m83chr();
  79        }
  80        break;
  81   case 0x8100:
  82               switch(V&0x3)
  83               {
  84               case 0x00:MIRROR_SET2(1);break;
  85               case 0x01:MIRROR_SET2(0);break;
  86               case 0x02:onemir(0);break;
  87               case 0x03:onemir(1);break;
  88               }
  89               break;
  90   case 0x8200:IRQCount&=0xFF00;IRQCount|=V;X6502_IRQEnd(FCEU_IQEXT);break;
  91   case 0x8201:IRQa=1;IRQCount&=0xFF;IRQCount|=V<<8;break;
  92   case 0x8300:ROM_BANK8(0x8000,V);break;
  93   case 0x8301:ROM_BANK8(0xA000,V);break;
  94   case 0x8302:ROM_BANK8(0xC000,V);break;
  95   case 0x8310:mapbyte2[0]=V;m83chr();break;
  96   case 0x8311:mapbyte2[1]=V;m83chr();break;
  97   case 0x8312:mapbyte2[2]=V;m83chr();break;
  98   case 0x8313:mapbyte2[3]=V;m83chr();break;
  99   case 0x8314:mapbyte2[4]=V;m83chr();break;
 100   case 0x8315:mapbyte2[5]=V;m83chr();break;
 101   case 0x8316:mapbyte2[6]=V;m83chr();break;
 102   case 0x8317:mapbyte2[7]=V;m83chr();break;
 103   case 0x8318:mapbyte1[1]=V;m83prg();break;
 104  }
 105 // printf("$%04x:$%02x, $%04x\n",A,V,X.PC.W);
 106
 107 }
 108
 109 void Mapper83_init(void)
 110 {
 111  ROM_BANK8(0xc000,0x1e);
 112  ROM_BANK8(0xe000,0x1f);
 113
 114  MapIRQHook=m83IRQHook;
 115
 116  SetReadHandler(0x5100,0x5103,rdlow);
 117  SetWriteHandler(0x5100,0x5103,wrlow);
 118  SetWriteHandler(0x8000,0xffff,Mapper83_write);
 119  mapbyte1[1]=0xF;
 120 }