void PCE_PSG::SetRegister(const unsigned int id, const uint32 value)
{
const int ch = (id >> 8) & 0xF;
switch(id & 0xF0FF)
{
default: break;
case PSG_GSREG_SELECT:
select = value & 0x07;
break;
case PSG_GSREG_GBALANCE:
globalbalance = value & 0xFF;
break;
case PSG_GSREG_LFOFREQ:
lfofreq = value & 0xFF;
break;
case PSG_GSREG_LFOCTRL:
lfoctrl = value & 0x83;
RecalcFreqCache(0);
RecalcUOFunc(0);
RecalcFreqCache(1);
RecalcUOFunc(1);
break;
case PSG_GSREG_CH0_FREQ:
channel[ch].frequency = value & 0xFFF;
RecalcFreqCache(ch);
RecalcUOFunc(ch);
break;
case PSG_GSREG_CH0_CTRL:
channel[ch].control = value & 0xFF;
RecalcFreqCache(ch);
RecalcUOFunc(ch);
break;
case PSG_GSREG_CH0_BALANCE:
channel[ch].balance = value & 0xFF;
break;
case PSG_GSREG_CH0_WINDEX:
channel[ch].waveform_index = value & 0x1F;
break;
case PSG_GSREG_CH0_SCACHE:
channel[ch].dda = value & 0x1F;
break;
case PSG_GSREG_CH0_NCTRL:
channel[ch].noisectrl = value & 0xFF;
RecalcNoiseFreqCache(ch);
RecalcUOFunc(ch);
break;
case PSG_GSREG_CH0_LFSR:
channel[ch].lfsr = value & 0x7FFF;
break;
}
}
void PCEFast_PSG::Write(int32 timestamp, uint8 A, uint8 V)
{
A &= 0x0F;
if(A == 0x00)
{
select = (V & 0x07);
return;
}
Update(timestamp);
psg_channel *ch = &channel[select];
//if(A == 0x01 || select == 5)
// printf("Write Ch: %d %04x %02x, %d\n", select, A, V, timestamp);
switch(A)
{
default: break;
case 0x01: /* Global sound balance */
globalbalance = V;
vol_pending = true;
break;
case 0x02: /* Channel frequency (LSB) */
if(select > 5) return; // no more than 6 channels, silly game.
ch->frequency = (ch->frequency & 0x0F00) | V;
RecalcFreqCache(select);
RecalcUOFunc(select);
break;
case 0x03: /* Channel frequency (MSB) */
if(select > 5) return; // no more than 6 channels, silly game.
ch->frequency = (ch->frequency & 0x00FF) | ((V & 0x0F) << 8);
RecalcFreqCache(select);
RecalcUOFunc(select);
break;
case 0x04: /* Channel enable, DDA, volume */
if(select > 5) return; // no more than 6 channels, silly game.
if((ch->control & 0x40) && !(V & 0x40))
{
ch->waveform_index = 0;
ch->dda = ch->waveform[ch->waveform_index];
ch->counter = ch->freq_cache;
}
if(!(ch->control & 0x80) && (V & 0x80))
{
if(!(V & 0x40))
{
ch->waveform_index = (ch->waveform_index + 1) & 0x1F;
ch->dda = ch->waveform[ch->waveform_index];
}
}
ch->control = V;
RecalcFreqCache(select);
RecalcUOFunc(select);
vol_pending = true;
break;
case 0x05: /* Channel balance */
if(select > 5) return; // no more than 6 channels, silly game.
ch->balance = V;
vol_pending = true;
break;
case 0x06: /* Channel waveform data */
if(select > 5) return; // no more than 6 channels, silly game.
V &= 0x1F;
if(!(ch->control & 0x40))
{
ch->samp_accum -= ch->waveform[ch->waveform_index];
ch->waveform[ch->waveform_index] = V;
ch->samp_accum += ch->waveform[ch->waveform_index];
}
if((ch->control & 0xC0) == 0x00)
ch->waveform_index = ((ch->waveform_index + 1) & 0x1F);
if(ch->control & 0x80)
{
// According to my tests(on SuperGrafx), writing to this channel
// will update the waveform value cache/latch regardless of DDA mode being enabled.
ch->dda = V;
}
break;
case 0x07: /* Noise enable and frequency */
if(select > 5) return; // no more than 6 channels, silly game.
if(select >= 4)
{
ch->noisectrl = V;
RecalcNoiseFreqCache(select);
RecalcUOFunc(select);
}
break;
case 0x08: /* LFO frequency */
lfofreq = V & 0xFF;
//printf("LFO Freq: %02x\n", V);
break;
case 0x09: /* LFO trigger and control */
//printf("LFO Ctrl: %02x\n", V);
if(V & 0x80)
{
channel[1].waveform_index = 0;
channel[1].dda = channel[1].waveform[channel[1].waveform_index];
channel[1].counter = channel[1].freq_cache;
}
lfoctrl = V;
RecalcFreqCache(0);
RecalcUOFunc(0);
RecalcFreqCache(1);
RecalcUOFunc(1);
break;
}
}
