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 namespace N5200 {
  13
  14 #define SET_BANK(s, e, w, r) { \
  15         int sb = (s) >> 11, eb = (e) >> 11; \
  16         for(int i = sb; i <= eb; i++) { \
  17                 if((w) == wdmy) { \
  18                         wbank[i] = wdmy; \
  19                 } else { \
  20                         wbank[i] = (w) + 0x800 * (i - sb); \
  21                 } \
  22                 if((r) == rdmy) { \
  23                         rbank[i] = rdmy; \
  24                 } else { \
  25                         rbank[i] = (r) + 0x800 * (i - sb); \
  26                 } \
  27         } \
  28 }
  29
  30 void MEMORY::initialize()
  31 {
  32         // init memory
  33         memset(ram, 0, sizeof(ram));
  34         memset(exram, 0, sizeof(exram));
  35         memset(vram, 0, sizeof(vram));
  36         memset(tvram, 0, sizeof(tvram));
  37         memset(backup, 0, sizeof(backup));
  38         memset(ipl, 0xff, sizeof(ipl));
  39         memset(rdmy, 0xff, sizeof(rdmy));
  40
  41         // load rom image
  42         FILEIO* fio = new FILEIO();
  43         if(fio->Fopen(create_local_path(_T("IPL.ROM")), FILEIO_READ_BINARY)) {
  44                 fio->Fread(ipl, sizeof(ipl), 1);
  45                 fio->Fclose();
  46                 for(int i = 0xa8e; i < 0xafc; i++) {
  47                         ipl[i] = 0x90;
  48                 }
  49         }
  50         delete fio;
  51 }
  52
  53 void MEMORY::release()
  54 {
  55         // save ram image
  56         FILEIO* fio = new FILEIO();
  57         if(fio->Fopen(create_local_path(_T("TVRAM.BIN")), FILEIO_WRITE_BINARY)) {
  58                 fio->Fwrite(tvram, sizeof(tvram), 1);
  59                 fio->Fclose();
  60         }
  61         delete fio;
  62 }
  63
  64 void MEMORY::reset()
  65 {
  66         SET_BANK(0x000000, 0xffffff, wdmy, rdmy);
  67         SET_BANK(0x000000, 0x0bffff, ram, ram);
  68         SET_BANK(0x0c0000, 0x0dffff, vram, vram);       // ???
  69         SET_BANK(0x0e0000, 0x0e77ff, tvram, tvram);
  70         SET_BANK(0x0e7800, 0x0effff, backup, backup);
  71         SET_BANK(0x0f0000, 0x0fffff, wdmy, ipl);
  72         SET_BANK(0x100000, 0x1fffff, exram, exram);
  73         SET_BANK(0xff0000, 0xffffff, wdmy, ipl);
  74
  75         protect = true;
  76 }
  77
  78 void MEMORY::write_data8(uint32_t addr, uint32_t data)
  79 {
  80         addr &= 0xffffff;
  81         if(0xe7800 <= addr && addr < 0xf0000 && protect) {
  82                 return;
  83         }
  84         wbank[addr >> 11][addr & 0x7ff] = data;
  85 }
  86
  87 uint32_t MEMORY::read_data8(uint32_t addr)
  88 {
  89         addr &= 0xffffff;
  90         return rbank[addr >> 11][addr & 0x7ff];
  91 }
  92
  93 void MEMORY::write_io8(uint32_t addr, uint32_t data)
  94 {
  95         switch(addr) {
  96         case 0x74:
  97                 protect = ((data & 1) != 0);
  98                 break;
  99         }
 100 }
 101
 102 uint32_t MEMORY::read_io8(uint32_t addr)
 103 {
 104         return 0xff;
 105 }
 106
 107 }