source/src/vm/fmtowns/towns_sysrom.cpp

   1 /*
   2         FUJITSU FM Towns Emulator 'eFMTowns'
   3
   4         Author : Kyuma.Ohta <whatisthis.sowhat _at_ gmail.com>
   5         Date   : 2019.01.09-
   6
   7         [ SYSTEM rom & RAM area 0x000f8000 - 0x000fffff]
   8         * MEMORY :
   9         *   0x000f8000 - 0x000fffff : RAM / DICTIONARY (BANKED)
  10         *   0xfffc0000 - 0xffffffff : SYSTEM ROM
  11         * I/O :
  12         *   0x0480                         : F8 BANK
  13 */
  14
  15 #include "./towns_common.h"
  16 #include "./towns_sysrom.h"
  17 #include "./towns_dictionary.h"
  18 #include "../../fileio.h"
  19
  20 namespace FMTOWNS {
  21 void SYSROM::initialize()
  22 {
  23         memset(rom, 0xff, sizeof(rom));
  24
  25         FILEIO* fio = new FILEIO();
  26         if(fio->Fopen(create_local_path(_T("FMT_SYS.ROM")), FILEIO_READ_BINARY)) { // DICTIONARIES
  27                 fio->Fread(rom, sizeof(rom), 1);
  28                 fio->Fclose();
  29         }
  30
  31 }
  32
  33
  34 void SYSROM::reset()
  35 {
  36 }
  37
  38 uint32_t SYSROM::read_memory_mapped_io8(uint32_t addr)
  39 {
  40         uint8_t n_data = 0xff;
  41         if(addr < 0xfffc0000) { // Banked (from MSDOS/i86 compatible mode)
  42                 if((addr >= 0x000f8000) && (addr < 0x00100000)) {
  43                         n_data = rom[(addr & 0x7fff) + 0x38000];
  44                 }
  45         } else {
  46                 n_data = rom[addr & 0x3ffff];
  47         }
  48         return (uint32_t)n_data;
  49 }
  50
  51 uint32_t SYSROM::read_memory_mapped_io16(uint32_t addr)
  52 {
  53         pair16_t nd;
  54         int dummy;
  55         nd.w = 0x00;
  56         // OK?
  57         nd.b.l = read_memory_mapped_io8(addr + 0);
  58         nd.b.h = read_memory_mapped_io8(addr + 1);
  59         return nd.w;
  60 }
  61
  62 uint32_t SYSROM::read_memory_mapped_io32(uint32_t addr)
  63 {
  64         pair32_t nd;
  65         nd.d = 0x00;
  66         // OK?
  67         nd.b.l  = read_memory_mapped_io8(addr + 0);
  68         nd.b.h  = read_memory_mapped_io8(addr + 1);
  69         nd.b.h2 = read_memory_mapped_io8(addr + 2);
  70         nd.b.h3 = read_memory_mapped_io8(addr + 3);
  71         return nd.d;
  72 }
  73
  74 void SYSROM::write_memory_mapped_io8(uint32_t addr, uint32_t data)
  75 {
  76         // ADDR >= 0xfffc0000
  77         return;
  78 }
  79
  80
  81 void SYSROM::write_memory_mapped_io16(uint32_t addr, uint32_t data)
  82 {
  83         pair16_t nd;
  84         nd.w = (uint16_t)data;
  85         // OK?
  86         write_memory_mapped_io8(addr + 0, nd.b.l);
  87         write_memory_mapped_io8(addr + 1, nd.b.h);
  88 }
  89
  90 void SYSROM::write_memory_mapped_io32(uint32_t addr, uint32_t data)
  91 {
  92         pair32_t nd;
  93         nd.d = data;
  94         write_memory_mapped_io8(addr + 0, nd.b.l);
  95         write_memory_mapped_io8(addr + 1, nd.b.h);
  96         write_memory_mapped_io8(addr + 2, nd.b.h2);
  97         write_memory_mapped_io8(addr + 3, nd.b.h3);
  98 }
  99
 100
 101 }