source/src/vm/pc8201/memory.cpp

   1 /*
   2         NEC PC-8201 Emulator 'ePC-8201'
   3
   4         Author : Takeda.Toshiya
   5         Date   : 2009.03.31-
   6
   7         [ memory ]
   8 */
   9
  10 #include "memory.h"
  11 #include "cmt.h"
  12 #include "../datarec.h"
  13 #include "../upd1990a.h"
  14
  15 #define SET_BANK(s, e, w, r) { \
  16         int sb = (s) >> 12, eb = (e) >> 12; \
  17         for(int i = sb; i <= eb; i++) { \
  18                 if((w) == wdmy) { \
  19                         wbank[i] = wdmy; \
  20                 } else { \
  21                         wbank[i] = (w) + 0x1000 * (i - sb); \
  22                 } \
  23                 if((r) == rdmy) { \
  24                         rbank[i] = rdmy; \
  25                 } else { \
  26                         rbank[i] = (r) + 0x1000 * (i - sb); \
  27                 } \
  28         } \
  29 }
  30
  31 void PC8201_MEMORY::initialize()
  32 {
  33         // init memory
  34         memset(ram, 0, sizeof(ram));
  35         memset(ipl, 0xff, sizeof(ipl));
  36         memset(ext, 0xff, sizeof(ext));
  37         memset(rdmy, 0xff, sizeof(rdmy));
  38
  39         // load rom / ram images
  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         }
  45         if(fio->Fopen(create_local_path(_T("EXT.ROM")), FILEIO_READ_BINARY)) {
  46                 fio->Fread(ext, sizeof(ext), 1);
  47                 fio->Fclose();
  48         }
  49         if(fio->Fopen(create_local_path(_T("RAM.BIN")), FILEIO_READ_BINARY)) {
  50                 fio->Fread(ram, sizeof(ram), 1);
  51                 fio->Fclose();
  52         }
  53         delete fio;
  54 }
  55
  56 void PC8201_MEMORY::release()
  57 {
  58         // save ram image
  59         FILEIO* fio = new FILEIO();
  60         if(fio->Fopen(create_local_path(_T("RAM.BIN")), FILEIO_WRITE_BINARY)) {
  61                 fio->Fwrite(ram, sizeof(ram), 1);
  62                 fio->Fclose();
  63         }
  64         delete fio;
  65 }
  66
  67 void PC8201_MEMORY::reset()
  68 {
  69         sio = bank = 0;
  70         update_bank();
  71 }
  72
  73 void PC8201_MEMORY::write_data8(uint32_t addr, uint32_t data)
  74 {
  75         addr &= 0xffff;
  76         wbank[addr >> 12][addr & 0xfff] = data;
  77 }
  78
  79 uint32_t PC8201_MEMORY::read_data8(uint32_t addr)
  80 {
  81         addr &= 0xffff;
  82         return rbank[addr >> 12][addr & 0xfff];
  83 }
  84
  85 void PC8201_MEMORY::write_io8(uint32_t addr, uint32_t data)
  86 {
  87         switch(addr & 0xf0) {
  88         case 0x90:
  89                 // system control
  90                 if((sio & 8) != (data & 8)) {
  91                         d_cmt->write_signal(SIG_CMT_REMOTE, data, 8);
  92                         d_drec->write_signal(SIG_DATAREC_REMOTE, data, 8);
  93                 }
  94                 if((sio & 0x10) != (data & 0x10)) {
  95                         d_rtc->write_signal(SIG_UPD1990A_STB, data, 0x10);
  96                 }
  97                 sio = data;
  98                 break;
  99         case 0xa0:
 100                 // bank control
 101                 bank = data;
 102                 update_bank();
 103                 break;
 104         }
 105 }
 106
 107 uint32_t PC8201_MEMORY::read_io8(uint32_t addr)
 108 {
 109         // $A0: bank status
 110         return (sio & 0xc0) | (bank & 0xf);
 111 }
 112
 113 void PC8201_MEMORY::update_bank()
 114 {
 115         switch(bank & 3) {
 116         case 0:
 117                 SET_BANK(0x0000, 0x7fff, wdmy, ipl);
 118                 break;
 119         case 1:
 120                 SET_BANK(0x0000, 0x7fff, wdmy, ext);
 121                 break;
 122         case 2:
 123                 SET_BANK(0x0000, 0x7fff, ram + 0x08000, ram + 0x08000);
 124                 break;
 125         case 3:
 126                 SET_BANK(0x0000, 0x7fff, ram + 0x10000, ram + 0x10000);
 127                 break;
 128         }
 129         switch((bank >> 2) & 3) {
 130         case 0:
 131                 SET_BANK(0x8000, 0xffff, ram + 0x00000, ram + 0x00000);
 132                 break;
 133         case 1:
 134                 SET_BANK(0x8000, 0xffff, wdmy, rdmy);
 135                 break;
 136         case 2:
 137                 SET_BANK(0x8000, 0xffff, ram + 0x08000, ram + 0x08000);
 138                 break;
 139         case 3:
 140                 SET_BANK(0x8000, 0xffff, ram + 0x10000, ram + 0x10000);
 141                 break;
 142         }
 143 }
 144
 145 #define STATE_VERSION   1
 146
 147 bool PC8201_MEMORY::process_state(FILEIO* state_fio, bool loading)
 148 {
 149         if(!state_fio->StateCheckUint32(STATE_VERSION)) {
 150                 return false;
 151         }
 152         if(!state_fio->StateCheckInt32(this_device_id)) {
 153                 return false;
 154         }
 155         state_fio->StateBuffer(ram, sizeof(ram), 1);
 156         state_fio->StateUint8(sio);
 157         state_fio->StateUint8(bank);
 158
 159         // post process
 160         if(loading) {
 161                 update_bank();
 162         }
 163         return true;
 164 }