merge mapper code from FCEUX

[fceu.git] / boards / 253.c

/* FCE Ultra - NES/Famicom Emulator\r
 *\r
 * Copyright notice for this file:\r
 *  Copyright (C) 2009 CaH4e3\r
 *\r
 * This program is free software; you can redistribute it and/or modify\r
 * it under the terms of the GNU General Public License as published by\r
 * the Free Software Foundation; either version 2 of the License, or\r
 * (at your option) any later version.\r
 *\r
 * This program is distributed in the hope that it will be useful,\r
 * but WITHOUT ANY WARRANTY; without even the implied warranty of\r
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the\r
 * GNU General Public License for more details.\r
 *\r
 * You should have received a copy of the GNU General Public License\r
 * along with this program; if not, write to the Free Software\r
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA\r
 */\r
\r
#include "mapinc.h"\r
\r
static uint8 chrlo[8], chrhi[8], prg[2], mirr, vlock;\r
static int32 IRQa, IRQCount, IRQLatch, IRQClock; \r
static uint8 *WRAM=NULL;\r
static uint32 WRAMSIZE;\r
static uint8 *CHRRAM=NULL;\r
static uint32 CHRRAMSIZE;\r
\r
static SFORMAT StateRegs[]=\r
{\r
  {chrlo, 8, "CHRLO"},\r
  {chrhi, 8, "CHRHI"},\r
  {prg, 2, "PRGR"},\r
  {&mirr, 1, "MIRR"},\r
  {&vlock, 1, "VLOCK"},\r
  {&IRQa, 4, "IRQA"},\r
  {&IRQCount, 4, "IRQC"},\r
  {&IRQLatch, 4, "IRQL"},\r
  {&IRQClock, 4, "IRQK"},\r
  {0}\r
};\r
\r
static void Sync(void)\r
{\r
  uint8 i;\r
  setprg8r(0x10,0x6000,0);\r
  setprg8(0x8000,prg[0]);\r
  setprg8(0xa000,prg[1]);\r
  setprg8(0xc000,~1);\r
  setprg8(0xe000,~0);\r
  for(i=0; i<8; i++)\r
  {\r
    uint32 chr = chrlo[i]|(chrhi[i]<<8);\r
    if(chrlo[i]==0xc8)\r
    {\r
      vlock = 0;\r
      continue;\r
    }\r
    else if(chrlo[i]==0x88)\r
    {\r
      vlock = 1;\r
      continue;\r
    }\r
    if(((chrlo[i]==4)||(chrlo[i]==5))&&!vlock)\r
      setchr1r(0x10,i<<10,chr&1);\r
    else\r
      setchr1(i<<10,chr);\r
  }\r
  switch(mirr)\r
  {\r
    case 0: setmirror(MI_V); break;\r
    case 1: setmirror(MI_H); break;\r
    case 2: setmirror(MI_0); break;\r
    case 3: setmirror(MI_1); break;\r
  }\r
}\r
\r
static DECLFW(M253Write)\r
{\r
  if((A>=0xB000)&&(A<=0xE00C))\r
  {\r
    uint8 ind=((((A&8)|(A>>8))>>3)+2)&7;\r
    uint8 sar=A&4;\r
    chrlo[ind]=(chrlo[ind]&(0xF0>>sar))|((V&0x0F)<<sar);\r
    if(A&4)\r
      chrhi[ind]=V>>4;\r
    Sync();\r
  }\r
  else\r
   switch(A)\r
    {\r
      case 0x8010: prg[0]=V; Sync(); break;\r
      case 0xA010: prg[1]=V; Sync(); break;\r
      case 0x9400: mirr=V&3; Sync(); break;\r
      case 0xF000: IRQLatch = (IRQLatch & 0xF0) | (V & 0x0F); break;\r
      case 0xF004: IRQLatch = (IRQLatch & 0x0F) | (V << 4); break;\r
      case 0xF008:\r
        IRQa = V&3;\r
        if(IRQa&2)\r
        {\r
          IRQCount = IRQLatch;\r
          IRQClock = 0;\r
        }\r
        X6502_IRQEnd(FCEU_IQEXT);\r
        break;\r
    }\r
}\r
\r
static void M253Power(void)\r
{\r
  Sync();\r
  SetReadHandler(0x6000,0x7FFF,CartBR);\r
  SetWriteHandler(0x6000,0x7FFF,CartBW);\r
  SetReadHandler(0x8000,0xFFFF,CartBR);\r
  SetWriteHandler(0x8000,0xFFFF,M253Write);\r
}\r
\r
static void M253Close(void)\r
{\r
  if(WRAM)\r
    FCEU_gfree(WRAM);\r
  if(CHRRAM)\r
    FCEU_gfree(CHRRAM);\r
  WRAM=CHRRAM=NULL;\r
}\r
\r
static void M253IRQ(int cycles)\r
{\r
  if(IRQa&2) \r
  {\r
    if((IRQClock+=cycles)>=0x72) \r
    {\r
      IRQClock -= 0x72;\r
      if(IRQCount==0xFF)  \r
      {\r
        IRQCount = IRQLatch;\r
        IRQa = IRQa|((IRQa&1)<<1);\r
        X6502_IRQBegin(FCEU_IQEXT);\r
      }\r
      else \r
        IRQCount++;\r
    }\r
  }\r
}\r
\r
static void StateRestore(int version)\r
{\r
  Sync();\r
}\r
\r
void Mapper253_Init(CartInfo *info)\r
{\r
  info->Power=M253Power;\r
  info->Close=M253Close;\r
  MapIRQHook=M253IRQ;\r
  GameStateRestore=StateRestore;\r
\r
  CHRRAMSIZE=4096;\r
  CHRRAM=(uint8*)FCEU_gmalloc(CHRRAMSIZE);\r
  SetupCartCHRMapping(0x10,CHRRAM,CHRRAMSIZE,1);\r
  AddExState(CHRRAM, CHRRAMSIZE, 0, "CRAM");\r
\r
  WRAMSIZE=8192;\r
  WRAM=(uint8*)FCEU_gmalloc(WRAMSIZE);\r
  SetupCartPRGMapping(0x10,WRAM,WRAMSIZE,1);\r
  AddExState(WRAM, WRAMSIZE, 0, "WRAM");\r
  if(info->battery)\r
  {\r
    info->SaveGame[0]=WRAM;\r
    info->SaveGameLen[0]=WRAMSIZE;\r
  }\r
\r
  AddExState(&StateRegs, ~0, 0, 0);\r
}\r