source/src/vm/tms3631.cpp

   1 /*
   2         Skelton for retropc emulator
   3
   4         Origin : Neko Project 2
   5         Author : Takeda.Toshiya
   6         Date   : 2015.09.29-
   7
   8         [ TMS3631 ]
   9 */
  10
  11 #include "tms3631.h"
  12
  13 // from tms3631c.c
  14 static const uint16_t np2_freq_table[] = {
  15         0,      0x051B, 0x0569, 0x05BB, 0x0613, 0x066F, 0x06D1,
  16                 0x0739, 0x07A7, 0x081B, 0x0897, 0x091A, 0x09A4, 0,0,0,
  17         0,      0x0A37, 0x0AD3, 0x0B77, 0x0C26, 0x0CDF, 0x0DA3,
  18                 0x0E72, 0x0F4E, 0x1037, 0x112E, 0x1234, 0x1349, 0,0,0,
  19         0,      0x146E, 0x15A6, 0x16EF, 0x184C, 0x19BE, 0x1B46,
  20                 0x1CE5, 0x1E9D, 0x206F, 0x225D, 0x2468, 0x2692, 0,0,0,
  21         0,      0x28DD, 0x2B4C, 0x2DDF, 0x3099, 0x337D, 0x368D,
  22                 0x39CB, 0x3D3B, 0x40DF, 0x44BA, 0x48D1, 0x4D25, 0x51BB, 0,0
  23 };
  24
  25 void TMS3631::reset()
  26 {
  27         datareg = maskreg = 0;
  28         memset(ch, 0, sizeof(ch));
  29         channel = 0;
  30         set_key = false;
  31 }
  32
  33 void TMS3631::write_signal(int id, uint32_t data, uint32_t mask)
  34 {
  35         if(id == SIG_TMS3631_ENVELOP1) {
  36                 envelop1 = (envelop1 & ~mask) | (data & mask);
  37         } else if(id == SIG_TMS3631_ENVELOP2) {
  38                 envelop2 = (envelop2 & ~mask) | (data & mask);
  39         } else if(id == SIG_TMS3631_DATAREG) {
  40                 // from board14.c
  41                 data = (datareg & ~mask) | (data & mask);
  42                 if(data & 0x80) {
  43                         if(!(datareg & 0x80)) {
  44                                 set_key = true;
  45                                 channel = 0;
  46                         } else if(set_key) {
  47                                 ch[channel].freq = freq_table[data & 0x3f];
  48                                 set_key = false;
  49                         } else if(!(data & 0x40) && (datareg & 0x40)) {
  50                                 set_key = true;
  51                                 channel = (channel + 1) & 7;
  52                         }
  53                 }
  54                 datareg = data;
  55         } else if(id == SIG_TMS3631_MASKREG) {
  56                 maskreg = (maskreg & ~mask) | (data & mask);
  57         }
  58 }
  59
  60 void TMS3631::mix(int32_t* buffer, int cnt)
  61 {
  62         // from tms3631g.c
  63         for(int i = 0; i < cnt; i++) {
  64                 int data = 0;
  65                 for(int j = 0; j < 2; j++) {
  66                         if((maskreg & (1 << j)) && ch[j].freq != 0) {
  67                                 for(int k = 0; k < 4; k++) {
  68                                         ch[j].count += ch[j].freq;
  69                                         data += (ch[j].count & 0x10000) ? 1 : -1;
  70                                 }
  71                         }
  72                 }
  73                 int vol_l = data * vol;
  74                 int vol_r = data * vol;
  75                 for(int j = 2; j < 5; j++) {
  76                         if((maskreg & (1 << j)) && ch[j].freq != 0) {
  77                                 for(int k = 0; k < 4; k++) {
  78                                         ch[j].count += ch[j].freq;
  79                                         vol_l += feet[(ch[j].count >> 16) & 15];
  80                                 }
  81                         }
  82                 }
  83                 for(int j = 5; j < 8; j++) {
  84                         if((maskreg & (1 << j)) && ch[j].freq != 0) {
  85                                 for(int k = 0; k < 4; k++) {
  86                                         ch[j].count += ch[j].freq;
  87                                         vol_r += feet[(ch[j].count >> 16) & 15];
  88                                 }
  89                         }
  90                 }
  91                 *buffer++ += apply_volume(vol_l, volume_l); // L
  92                 *buffer++ += apply_volume(vol_r, volume_r); // R
  93         }
  94 }
  95
  96 void TMS3631::set_volume(int ch, int decibel_l, int decibel_r)
  97 {
  98         volume_l = decibel_to_volume(decibel_l);
  99         volume_r = decibel_to_volume(decibel_r);
 100 }
 101
 102 void TMS3631::initialize_sound(int rate, int volume)
 103 {
 104         // from tms3631c.c
 105         for(int i = 0; i < 64; i++) {
 106                 freq_table[i] = (uint32_t)((double)np2_freq_table[i] * 11025.0 / (double)rate / 2.0 + 0.5);
 107         }
 108         for(int i = 0; i < 16; i++) {
 109                 int data = 0;
 110                 for(int j = 0; j < 4; j++) {
 111                         data += (volume / 8) * ((i & (1 << j)) ? 1 : -1);
 112                 }
 113                 feet[i] = data;
 114         }
 115         vol = volume / 8;
 116 }
 117
 118 #define STATE_VERSION   1
 119
 120 void TMS3631::save_state(FILEIO* state_fio)
 121 {
 122         state_fio->FputUint32(STATE_VERSION);
 123         state_fio->FputInt32(this_device_id);
 124
 125         state_fio->FputUint8(envelop1);
 126         state_fio->FputUint8(envelop2);
 127         state_fio->FputUint8(datareg);
 128         state_fio->FputUint8(maskreg);
 129         state_fio->Fwrite(ch, sizeof(ch), 1);
 130         state_fio->FputUint8(channel);
 131         state_fio->FputBool(set_key);
 132 }
 133
 134 bool TMS3631::load_state(FILEIO* state_fio)
 135 {
 136         if(state_fio->FgetUint32() != STATE_VERSION) {
 137                 return false;
 138         }
 139         if(state_fio->FgetInt32() != this_device_id) {
 140                 return false;
 141         }
 142         envelop1 = state_fio->FgetUint8();
 143         envelop2 = state_fio->FgetUint8();
 144         datareg = state_fio->FgetUint8();
 145         maskreg = state_fio->FgetUint8();
 146         state_fio->Fread(ch, sizeof(ch), 1);
 147         channel = state_fio->FgetUint8();
 148         set_key = state_fio->FgetBool();
 149         return true;
 150 }
 151