source/src/vm/pc8201/cmt.cpp

   1 /*\r
   2         NEC PC-8201 Emulator 'ePC-8201'\r
   3 \r
   4         Author : Takeda.Toshiya\r
   5         Date   : 2013.04.22-\r
   6 \r
   7         [ cmt (record only) ]\r
   8 */\r
   9 \r
  10 #include "cmt.h"\r
  11 #include "../../fileio.h"\r
  12 \r
  13 #pragma pack(1)\r
  14 typedef struct {\r
  15         char id[4];\r
  16         uint32 size;\r
  17 } wav_chunk_t;\r
  18 #pragma pack()\r
  19 \r
  20 #pragma pack(1)\r
  21 typedef struct {\r
  22         wav_chunk_t riff_chunk;\r
  23         char wave[4];\r
  24         wav_chunk_t fmt_chunk;\r
  25         uint16 format_id;\r
  26         uint16 channels;\r
  27         uint32 sample_rate;\r
  28         uint32 data_speed;\r
  29         uint16 block_size;\r
  30         uint16 sample_bits;\r
  31 } wav_header_t;\r
  32 #pragma pack()\r
  33 \r
  34 #define SAMPLE_RATE 48000\r
  35 \r
  36 void CMT::initialize()\r
  37 {\r
  38         fio = new FILEIO();\r
  39         rec = remote = false;\r
  40 }\r
  41 \r
  42 void CMT::release()\r
  43 {\r
  44         close_tape();\r
  45         delete fio;\r
  46 }\r
  47 \r
  48 void CMT::reset()\r
  49 {\r
  50         close_tape();\r
  51         rec = remote = false;\r
  52 }\r
  53 \r
  54 void CMT::write_buffer(uint8 value, int samples)\r
  55 {\r
  56         if(is_wav) {\r
  57                 for(int i = 0; i < samples; i++) {\r
  58                         buffer[bufcnt++] = value;\r
  59                         if(bufcnt == sizeof(buffer)) {\r
  60                                 fio->Fwrite(buffer, sizeof(buffer), 1);\r
  61                                 bufcnt = 0;\r
  62                         }\r
  63                 }\r
  64         } else {\r
  65                 value = (value > 128) ? 0x80 : 0;\r
  66                 while(samples > 0) {\r
  67                         int s = min(samples, 0x7f);\r
  68                         samples -= s;\r
  69                         buffer[bufcnt++] = value | s;\r
  70                         if(bufcnt == sizeof(buffer)) {\r
  71                                 fio->Fwrite(buffer, sizeof(buffer), 1);\r
  72                                 bufcnt = 0;\r
  73                         }\r
  74                 }\r
  75         }\r
  76 }\r
  77 \r
  78 void CMT::put_signal()\r
  79 {\r
  80         if(rec && remote) {\r
  81                 uint32 clock = passed_clock(prev_clock);\r
  82                 if(prev_signal == 1) {\r
  83                         // 2400Hz\r
  84                         int count = (int)(1200.0 * (double)clock / (double)CPU_CLOCKS + 0.5) * 2;\r
  85                         for(int i = 0; i < count; i++) {\r
  86                                 write_buffer(0xff, SAMPLE_RATE / 2400 / 2);\r
  87                                 write_buffer(0x00, SAMPLE_RATE / 2400 / 2);\r
  88                         }\r
  89                 } else if(prev_signal == -1) {\r
  90                         // 1200Hz\r
  91                         int count = (int)(1200.0 * (double)clock / (double)CPU_CLOCKS + 0.5);\r
  92                         for(int i = 0; i < count; i++) {\r
  93                                 write_buffer(0xff, SAMPLE_RATE / 1200 / 2);\r
  94                                 write_buffer(0x00, SAMPLE_RATE / 1200 / 2);\r
  95                         }\r
  96                 } else {\r
  97                         write_buffer(0x80, SAMPLE_RATE * clock / CPU_CLOCKS);\r
  98                 }\r
  99         }\r
 100 }\r
 101 \r
 102 void CMT::write_signal(int id, uint32 data, uint32 mask)\r
 103 {\r
 104         bool next = ((data & mask) != 0);\r
 105         \r
 106         if(id == SIG_CMT_REMOTE) {\r
 107                 if(!remote && next) {\r
 108                         // start\r
 109                         prev_signal = 0;\r
 110                         prev_clock = current_clock();\r
 111                 } else if(remote && !next) {\r
 112                         // stop\r
 113                         put_signal();\r
 114                 }\r
 115                 remote = next;\r
 116         } else if(id == SIG_CMT_SOD) {\r
 117                 if(remote) {\r
 118                         request_skip_frames();\r
 119                         put_signal();\r
 120                 }\r
 121                 prev_signal = next ? 1 : -1;\r
 122                 prev_clock = current_clock();\r
 123         }\r
 124 }\r
 125 \r
 126 void CMT::rec_tape(_TCHAR* file_path)\r
 127 {\r
 128         close_tape();\r
 129         \r
 130         if(fio->Fopen(file_path, FILEIO_WRITE_BINARY)) {\r
 131                 if(check_file_extension(file_path, _T(".wav"))) {\r
 132                         uint8 dummy[sizeof(wav_header_t) + sizeof(wav_chunk_t)];\r
 133                         memset(dummy, 0, sizeof(dummy));\r
 134                         fio->Fwrite(dummy, sizeof(dummy), 1);\r
 135                         is_wav = true;\r
 136                 }\r
 137                 bufcnt = 0;\r
 138                 rec = true;\r
 139         }\r
 140 }\r
 141 \r
 142 void CMT::close_tape()\r
 143 {\r
 144         // close file\r
 145         if(rec) {\r
 146                 if(bufcnt) {\r
 147                         fio->Fwrite(buffer, bufcnt, 1);\r
 148                 }\r
 149                 if(is_wav) {\r
 150                         uint32 length = fio->Ftell();\r
 151                         \r
 152                         wav_header_t wav_header;\r
 153                         wav_chunk_t wav_chunk;\r
 154                         \r
 155                         memcpy(wav_header.riff_chunk.id, "RIFF", 4);\r
 156                         wav_header.riff_chunk.size = length - 8;\r
 157                         memcpy(wav_header.wave, "WAVE", 4);\r
 158                         memcpy(wav_header.fmt_chunk.id, "fmt ", 4);\r
 159                         wav_header.fmt_chunk.size = 16;\r
 160                         wav_header.format_id = 1;\r
 161                         wav_header.channels = 1;\r
 162                         wav_header.sample_rate = SAMPLE_RATE;\r
 163                         wav_header.data_speed = SAMPLE_RATE;\r
 164                         wav_header.block_size = 1;\r
 165                         wav_header.sample_bits = 8;\r
 166                         \r
 167                         memcpy(wav_chunk.id, "data", 4);\r
 168                         wav_chunk.size = length - sizeof(wav_header) - sizeof(wav_chunk);\r
 169                         \r
 170                         fio->Fseek(0, FILEIO_SEEK_SET);\r
 171                         fio->Fwrite(&wav_header, sizeof(wav_header), 1);\r
 172                         fio->Fwrite(&wav_chunk, sizeof(wav_chunk), 1);\r
 173                 }\r
 174                 fio->Fclose();\r
 175         }\r
 176         is_wav = rec = false;\r
 177 }\r
 178 \r