source/src/vm/gamegear/memory.cpp

   1 /*
   2         SEGA GAME GEAR Emulator 'yaGAME GEAR'
   3
   4         Author : tanam
   5         Date   : 2013.08.24-
   6
   7         [ memory ]
   8 */
   9
  10 #include "memory.h"
  11
  12 void MEMORY::sms_mapper_w(uint32_t addr, uint32_t data)
  13 {
  14         /* Calculate ROM page index */
  15         uint8_t page = (data % pages);
  16
  17         /* Save frame control register data */
  18         fcr[addr] = data;
  19
  20         switch(addr)
  21         {
  22         case 0:
  23                 if (data & 8) {
  24                         save = 1;
  25                         /* Page in ROM */
  26                         cpu_readmap[4]  = &sram[(data & 4) ? 0x4000 : 0x0000];
  27                         cpu_readmap[5]  = &sram[(data & 4) ? 0x6000 : 0x2000];
  28                         cpu_writemap[4] = &sram[(data & 4) ? 0x4000 : 0x0000];
  29                         cpu_writemap[5] = &sram[(data & 4) ? 0x6000 : 0x2000];
  30                 } else {
  31                         /* Page in RAM */
  32                         cpu_readmap[4]  = &cart[((fcr[3] % pages) << 14) + 0x0000];
  33                         cpu_readmap[5]  = &cart[((fcr[3] % pages) << 14) + 0x2000];
  34                         cpu_writemap[4] = ram + 0x8000;
  35                         cpu_writemap[5] = ram + 0xA000;
  36                 }
  37                 break;
  38         case 1:
  39                 cpu_readmap[0] = &cart[(page << 14) + 0x0000];
  40                 cpu_readmap[1] = &cart[(page << 14) + 0x2000];
  41                 break;
  42         case 2:
  43                 cpu_readmap[2] = &cart[(page << 14) + 0x0000];
  44                 cpu_readmap[3] = &cart[(page << 14) + 0x2000];
  45                 break;
  46         case 3:
  47                 if (!(fcr[0] & 0x08)) {
  48                         cpu_readmap[4] = &cart[(page << 14) + 0x0000];
  49                         cpu_readmap[5] = &cart[(page << 14) + 0x2000];
  50                 }
  51                 break;
  52         }
  53 }
  54
  55 void MEMORY::initialize()
  56 {
  57         cart=NULL;
  58
  59         memset(ram, 0, sizeof(ram));
  60         memset(rdmy, 0xff, sizeof(rdmy));
  61     memset(sram, 0, sizeof(sram));
  62
  63         // set memory map
  64         cpu_readmap[0] = ram;
  65         cpu_readmap[1] = ram + 0x2000;
  66         cpu_readmap[2] = ram + 0x4000;
  67         cpu_readmap[3] = ram + 0x6000;
  68         cpu_readmap[4] = ram + 0x8000;
  69         cpu_readmap[5] = ram + 0xA000;
  70         cpu_readmap[6] = ram + 0xC000;
  71         cpu_readmap[7] = ram + 0xE000;
  72
  73         cpu_writemap[0] = ram;
  74         cpu_writemap[1] = ram + 0x2000;
  75         cpu_writemap[2] = ram + 0x4000;
  76         cpu_writemap[3] = ram + 0x6000;
  77         cpu_writemap[4] = ram + 0x8000;
  78         cpu_writemap[5] = ram + 0xA000;
  79         cpu_writemap[6] = ram + 0xC000;
  80         cpu_writemap[7] = ram + 0xE000;
  81
  82         fcr[0] = 0x00;
  83         fcr[1] = 0x00;
  84         fcr[2] = 0x01;
  85         fcr[3] = 0x00;
  86
  87         inserted = false;
  88 }
  89
  90 void MEMORY::release()
  91 {
  92         if (cart) free(cart);
  93 }
  94
  95 void MEMORY::bios()
  96 {
  97         FILEIO* fio = new FILEIO();
  98
  99         if(fio->Fopen(create_local_path(_T("COLECO.ROM")), FILEIO_READ_BINARY)) {
 100                 fio->Fseek(0, FILEIO_SEEK_END);
 101                 size=fio->Ftell();
 102                 pages = (size / 0x4000);
 103                 fio->Fseek(0, FILEIO_SEEK_SET);
 104                 if (size == 0x2000 && cpu_readmap[0] != cart) {
 105                         fio->Fread(ram, size, 1);
 106                         /* $0000-$1FFF mapped to internal ROM (8K) */
 107                         cpu_readmap[0]  = ram;
 108                         cpu_writemap[0] = ram;
 109                         /* $2000-$5FFF mapped to expansion */
 110                         cpu_readmap[1]  = rdmy;
 111                         cpu_readmap[2]  = rdmy;
 112                         /* $6000-$7FFF mapped to RAM (1K mirrored) */
 113                         cpu_readmap[3]  = ram + 0x6000;
 114                         /* $8000-$FFFF mapped to Cartridge ROM (max. 32K) */
 115                         if (!cart) {
 116                                 cpu_readmap[4] = ram + 0x8000;
 117                                 cpu_readmap[5] = ram + 0xA000;
 118                                 cpu_readmap[6] = ram + 0xC000;
 119                                 cpu_readmap[7] = ram + 0xE000;
 120                         }
 121                         cpu_writemap[0] = ram;
 122                         cpu_writemap[1] = ram + 0x2000;
 123                         cpu_writemap[2] = ram + 0x4000;
 124                         cpu_writemap[3] = ram + 0x6000;
 125                         cpu_writemap[4] = ram + 0x8000;
 126                         cpu_writemap[5] = ram + 0xA000;
 127                         cpu_writemap[6] = ram + 0xC000;
 128                         cpu_writemap[7] = ram + 0xE000;
 129                         fcr[0] = 0x00;
 130                         fcr[1] = 0x00;
 131                         fcr[2] = 0x01;
 132                         fcr[3] = 0x00;
 133                 }
 134                 fio->Fclose();
 135         }
 136         delete fio;
 137 }
 138
 139 void MEMORY::write_data8(uint32_t addr, uint32_t data)
 140 {
 141         cpu_writemap[(addr >> 13)][(addr & 0x1FFF)] = data;
 142         if (pages < 4) return;
 143         if (addr >= 0xFFFC) sms_mapper_w(addr & 3, data);
 144 }
 145
 146 uint32_t MEMORY::read_data8(uint32_t addr)
 147 {
 148         return cpu_readmap[(addr >> 13)][(addr & 0x1FFF)];
 149 }
 150
 151 void MEMORY::write_signal(int id, uint32_t data, uint32_t mask)
 152 {
 153         // from PIO-P6
 154         if(data & mask) {
 155                 cpu_readmap[0] = ram;
 156                 cpu_readmap[1] = ram + 0x2000;
 157                 cpu_readmap[2] = ram + 0x4000;
 158                 cpu_readmap[3] = ram + 0x6000;
 159                 cpu_readmap[4] = ram + 0x8000;
 160                 cpu_writemap[0] = ram;
 161                 cpu_writemap[1] = ram + 0x2000;
 162                 cpu_writemap[2] = ram + 0x4000;
 163                 cpu_writemap[3] = ram + 0x6000;
 164                 cpu_writemap[4] = ram + 0x8000;
 165         }
 166         else {
 167                 // ROM
 168                 cpu_readmap[0] = cart;
 169                 cpu_readmap[1] = rdmy;
 170                 cpu_readmap[2] = ram + 0x4000;
 171                 cpu_readmap[3] = ram + 0x6000;
 172                 cpu_readmap[4] = ram + 0x8000;
 173                 cpu_writemap[0] = ram;
 174                 cpu_writemap[1] = ram + 0x2000;
 175                 cpu_writemap[2] = ram + 0x4000;
 176                 cpu_writemap[3] = ram + 0x6000;
 177                 cpu_writemap[4] = ram + 0x8000;
 178         }
 179 }
 180
 181 void MEMORY::open_cart(const _TCHAR* file_path)
 182 {
 183         FILEIO* fio = new FILEIO();
 184
 185         if(fio->Fopen(file_path, FILEIO_READ_BINARY)) {
 186                 fio->Fseek(0, FILEIO_SEEK_END);
 187                 size=fio->Ftell();
 188                 pages = (size / 0x4000);
 189                 fio->Fseek(0, FILEIO_SEEK_SET);
 190                 if (cart) free(cart);
 191                 cart=(uint8_t *)malloc(size);
 192                 fio->Fread(cart, size, 1);
 193                 fio->Fclose();
 194                 delete fio;
 195                 inserted = true;
 196         } else {
 197                 delete fio;
 198                 return;
 199         }
 200         if (check_file_extension(file_path, _T(".col"))) {
 201                 /* $0000-$1FFF mapped to internal ROM (8K) */
 202                 cpu_readmap[0]  = ram;
 203                 cpu_writemap[0] = ram;
 204                 /* $2000-$5FFF mapped to expansion */
 205                 cpu_readmap[1]  = rdmy;
 206                 cpu_readmap[2]  = rdmy;
 207                 /* $6000-$7FFF mapped to RAM (1K mirrored) */
 208                 cpu_readmap[3]  = ram + 0x6000;
 209                 /* $8000-$FFFF mapped to Cartridge ROM (max. 32K) */
 210                 cpu_readmap[4] = cart;
 211                 if (size>0x2000) cpu_readmap[5] = cart + 0x2000;
 212                 else cpu_readmap[5] = rdmy;
 213                 if (size>0x4000) cpu_readmap[6] = cart + 0x4000;
 214                 else cpu_readmap[6] = rdmy;
 215                 if (size>0x6000) cpu_readmap[7] = cart + 0x6000;
 216                 else cpu_readmap[7] = rdmy;
 217         } else {
 218                 // set memory map
 219                 cpu_readmap[0] = cart;
 220                 if (size>0x2000) cpu_readmap[1] = cart + 0x2000;
 221                 else cpu_readmap[1] = rdmy;
 222                 if (size>0x4000) cpu_readmap[2] = cart + 0x4000;
 223                 else cpu_readmap[2] = rdmy;
 224                 if (size>0x6000) cpu_readmap[3] = cart + 0x6000;
 225                 else cpu_readmap[3] = rdmy;
 226                 if (size>0x8000) cpu_readmap[4] = cart + 0x8000;
 227                 else cpu_readmap[4] = ram + 0x8000;
 228                 if (size>0xA000) cpu_readmap[5] = cart + 0xA000;
 229                 else cpu_readmap[5] = ram + 0xA000;
 230                 cpu_readmap[6] = ram + 0xC000;
 231                 cpu_readmap[7] = ram + 0xE000;
 232         }
 233         if (_tcsicmp(file_path, _T("SMS.ROM"))) {
 234                 cart[0x77]=0;
 235                 cart[0x79]=0;
 236         }
 237         cpu_writemap[0] = ram;
 238         cpu_writemap[1] = ram + 0x2000;
 239         cpu_writemap[2] = ram + 0x4000;
 240         cpu_writemap[3] = ram + 0x6000;
 241         cpu_writemap[4] = ram + 0x8000;
 242         cpu_writemap[5] = ram + 0xA000;
 243         cpu_writemap[6] = ram + 0xC000;
 244         cpu_writemap[7] = ram + 0xE000;
 245         fcr[0] = 0x00;
 246         fcr[1] = 0x00;
 247         fcr[2] = 0x01;
 248         fcr[3] = 0x00;
 249 }
 250
 251 void MEMORY::close_cart()
 252 {
 253         if (cart) free(cart);
 254         initialize();
 255 }