boards/tengen.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 static uint8 cmd,mir,rmode,IRQmode;
  24 static uint8 DRegs[11];
  25 static uint8 IRQCount,IRQa,IRQLatch;
  26
  27 static SFORMAT Rambo_StateRegs[]={
  28         {&cmd, 1, "CMD"},
  29         {&mir, 1, "MIR"},
  30         {&rmode, 1, "RMOD"},
  31         {&IRQmode, 1, "IRQM"},
  32         {&IRQCount, 1, "IRQC"},
  33         {&IRQa, 1, "IRQA"},
  34         {&IRQLatch, 1, "IRQL"},
  35         {DRegs, 11, "DREG"},
  36         {0}
  37 };
  38
  39 static void FP_FASTAPASS(2) (*setchr1wrap)(unsigned int A, unsigned int V);
  40 static int nomirror;
  41
  42 static void FP_FASTAPASS(1) RAMBO1_IRQHook(int a)
  43 {
  44  static int smallcount;
  45  if(!IRQmode) return;
  46
  47  smallcount+=a;
  48  while(smallcount>=4)
  49  {
  50   smallcount-=4;
  51   IRQCount--;
  52   if(IRQCount==0xFF)
  53       if(IRQa) X6502_IRQBegin(FCEU_IQEXT);
  54  }
  55 }
  56
  57 static void RAMBO1_hb(void)
  58 {
  59       if(IRQmode) return;
  60   if(scanline==240) return;        /* hmm.  Maybe that should be an mmc3-only call in fce.c. */
  61       rmode=0;
  62       IRQCount--;
  63       if(IRQCount==0xFF)
  64       {
  65        if(IRQa)
  66        {
  67         rmode = 1;
  68         X6502_IRQBegin(FCEU_IQEXT);
  69        }
  70       }
  71 }
  72
  73 static void Synco(void)
  74 {
  75  int x;
  76
  77  if(cmd&0x20)
  78  {
  79   setchr1wrap(0x0000,DRegs[0]);
  80   setchr1wrap(0x0800,DRegs[1]);
  81   setchr1wrap(0x0400,DRegs[8]);
  82   setchr1wrap(0x0c00,DRegs[9]);
  83  }
  84  else
  85  {
  86   setchr1wrap(0x0000,(DRegs[0]&0xFE));
  87   setchr1wrap(0x0400,(DRegs[0]&0xFE)|1);
  88   setchr1wrap(0x0800,(DRegs[1]&0xFE));
  89   setchr1wrap(0x0C00,(DRegs[1]&0xFE)|1);
  90  }
  91
  92  for(x=0;x<4;x++)
  93   setchr1wrap(0x1000+x*0x400,DRegs[2+x]);
  94
  95  setprg8(0x8000,DRegs[6]);
  96  setprg8(0xA000,DRegs[7]);
  97
  98  setprg8(0xC000,DRegs[10]);
  99 }
 100
 101
 102 static DECLFW(RAMBO1_write)
 103 {
 104  switch(A&0xF001)
 105   {
 106     case 0xa000: mir=V&1;
 107                  if(!nomirror)
 108                    setmirror(mir^1);
 109                  break;
 110     case 0x8000: cmd = V;
 111                  break;
 112     case 0x8001: if((cmd&0xF)<10)
 113                      DRegs[cmd&0xF]=V;
 114                     else if((cmd&0xF)==0xF)
 115                      DRegs[10]=V;
 116                     Synco();
 117                     break;
 118     case 0xc000: IRQLatch=V;
 119                  if(rmode==1)
 120                    IRQCount=IRQLatch;
 121                  break;
 122     case 0xc001: rmode=1;
 123                     IRQCount=IRQLatch;
 124                     IRQmode=V&1;
 125                     break;
 126     case 0xE000: IRQa=0;
 127                  X6502_IRQEnd(FCEU_IQEXT);
 128                  if(rmode==1)
 129                    IRQCount=IRQLatch;
 130                  break;
 131     case 0xE001: IRQa=1;
 132                  if(rmode==1)
 133                    IRQCount=IRQLatch;
 134                     break;
 135   }
 136 }
 137
 138 static void RAMBO1_Restore(int version)
 139 {
 140  Synco();
 141  if(!nomirror)
 142   setmirror(mir^1);
 143 }
 144
 145 static void RAMBO1_init(void)
 146 {
 147         int x;
 148         for(x=0;x<11;x++)
 149          DRegs[x]=~0;
 150   cmd=mir=0;
 151         if(!nomirror)
 152          setmirror(1);
 153         Synco();
 154         GameHBIRQHook=RAMBO1_hb;
 155         MapIRQHook=RAMBO1_IRQHook;
 156         GameStateRestore=RAMBO1_Restore;
 157         SetWriteHandler(0x8000,0xffff,RAMBO1_write);
 158         AddExState(Rambo_StateRegs, ~0, 0, 0);
 159 }
 160
 161 static void FP_FASTAPASS(2) CHRWrap(unsigned int A, unsigned int V)
 162 {
 163  setchr1(A,V);
 164 }
 165
 166 void Mapper64_init(void)
 167 {
 168         setchr1wrap=CHRWrap;
 169         nomirror=0;
 170         RAMBO1_init();
 171 }
 172
 173 static int MirCache[8];
 174 static unsigned int PPUCHRBus;
 175
 176 static void FP_FASTAPASS(2) MirWrap(unsigned int A, unsigned int V)
 177 {
 178  MirCache[A>>10]=(V>>7)&1;
 179  if(PPUCHRBus==(A>>10))
 180   setmirror(MI_0+((V>>7)&1));
 181  setchr1(A,V);
 182 }
 183
 184 static void FP_FASTAPASS(1) MirrorFear(uint32 A)
 185 {
 186  A&=0x1FFF;
 187  A>>=10;
 188  PPUCHRBus=A;
 189  setmirror(MI_0+MirCache[A]);
 190 }
 191
 192 void Mapper158_init(void)
 193 {
 194         setchr1wrap=MirWrap;
 195         PPU_hook=MirrorFear;
 196         nomirror=1;
 197         RAMBO1_init();
 198 }