source/src/vm/n5200/memory.cpp

   1 /*
   2         NEC N5200 Emulator 'eN5200'
   3
   4         Author : Takeda.Toshiya
   5         Date   : 2009.06.03-
   6
   7         [ memory ]
   8 */
   9
  10 #include "./memory.h"
  11
  12 #define SET_BANK(s, e, w, r) { \
  13         int sb = (s) >> 11, eb = (e) >> 11; \
  14         for(int i = sb; i <= eb; i++) { \
  15                 if((w) == wdmy) { \
  16                         wbank[i] = wdmy; \
  17                 } else { \
  18                         wbank[i] = (w) + 0x800 * (i - sb); \
  19                 } \
  20                 if((r) == rdmy) { \
  21                         rbank[i] = rdmy; \
  22                 } else { \
  23                         rbank[i] = (r) + 0x800 * (i - sb); \
  24                 } \
  25         } \
  26 }
  27
  28 void N5200_MEMORY::initialize()
  29 {
  30         // init memory
  31         memset(ram, 0, sizeof(ram));
  32         memset(exram, 0, sizeof(exram));
  33         memset(vram, 0, sizeof(vram));
  34         memset(tvram, 0, sizeof(tvram));
  35         memset(backup, 0, sizeof(backup));
  36         memset(ipl, 0xff, sizeof(ipl));
  37         memset(rdmy, 0xff, sizeof(rdmy));
  38
  39         // load rom image
  40         FILEIO* fio = new FILEIO();
  41         if(fio->Fopen(create_local_path(_T("IPL.ROM")), FILEIO_READ_BINARY)) {
  42                 fio->Fread(ipl, sizeof(ipl), 1);
  43                 fio->Fclose();
  44                 for(int i = 0xa8e; i < 0xafc; i++) {
  45                         ipl[i] = 0x90;
  46                 }
  47         }
  48         delete fio;
  49 }
  50
  51 void N5200_MEMORY::release()
  52 {
  53         // save ram image
  54         FILEIO* fio = new FILEIO();
  55         if(fio->Fopen(create_local_path(_T("TVRAM.BIN")), FILEIO_WRITE_BINARY)) {
  56                 fio->Fwrite(tvram, sizeof(tvram), 1);
  57                 fio->Fclose();
  58         }
  59         delete fio;
  60 }
  61
  62 void N5200_MEMORY::reset()
  63 {
  64         SET_BANK(0x000000, 0xffffff, wdmy, rdmy);
  65         SET_BANK(0x000000, 0x0bffff, ram, ram);
  66         SET_BANK(0x0c0000, 0x0dffff, vram, vram);       // ???
  67         SET_BANK(0x0e0000, 0x0e77ff, tvram, tvram);
  68         SET_BANK(0x0e7800, 0x0effff, backup, backup);
  69         SET_BANK(0x0f0000, 0x0fffff, wdmy, ipl);
  70         SET_BANK(0x100000, 0x1fffff, exram, exram);
  71         SET_BANK(0xff0000, 0xffffff, wdmy, ipl);
  72
  73         protect = true;
  74 }
  75
  76 void N5200_MEMORY::write_data8(uint32_t addr, uint32_t data)
  77 {
  78         addr &= 0xffffff;
  79         if(0xe7800 <= addr && addr < 0xf0000 && protect) {
  80                 return;
  81         }
  82         wbank[addr >> 11][addr & 0x7ff] = data;
  83 }
  84
  85 uint32_t N5200_MEMORY::read_data8(uint32_t addr)
  86 {
  87         addr &= 0xffffff;
  88         return rbank[addr >> 11][addr & 0x7ff];
  89 }
  90
  91 void N5200_MEMORY::write_io8(uint32_t addr, uint32_t data)
  92 {
  93         switch(addr) {
  94         case 0x74:
  95                 protect = ((data & 1) != 0);
  96                 break;
  97         }
  98 }
  99
 100 uint32_t N5200_MEMORY::read_io8(uint32_t addr)
 101 {
 102         return 0xff;
 103 }
 104