/// <summary>
/// Resets this device
/// </summary>
public void Reset()
{
_frameBegins = HostVm.Cpu.Tacts;
LastRegisterIndex = 0;
PsgState = new PsgState(HostVm);
for (var i = 0; i < 0x0F; i++)
{
PsgState[i] = 0;
}
FrameCount = 0;
Overflow = 0;
SetRegisterValue(0);
_soundProvider?.Reset();
InitializeSampling();
}
/// <summary>
/// Create the PSG sample for the specified tact
/// </summary>
/// <param name="tact">CPU tact to create the sample for</param>
/// <returns></returns>
private float CreateSampleFor(long tact)
{
var noise = PsgState.GetNoiseSample(tact);
var channelA = PsgState.GetChannelASample(tact);
if (PsgState.NoiseAEnabled && noise > channelA)
{
channelA = noise;
}
var channelB = PsgState.GetChannelBSample(tact);
if (PsgState.NoiseBEnabled && noise > channelB)
{
channelB = noise;
}
var channelC = PsgState.GetChannelCSample(tact);
if (PsgState.NoiseCEnabled && noise > channelC)
{
channelC = noise;
}
// --- Mix channels
var sample = (channelA * PsgState.GetAmplitudeA(tact) +
channelB * PsgState.GetAmplitudeB(tact) +
channelC * PsgState.GetAmplitudeC(tact)) / 3;
// --- Remove DC
_filtSum += -_delay[_filterIndex] + sample;
_delay[_filterIndex] = sample;
sample = sample - _filtSum / DC_FITER_SIZE;
_filterIndex++;
if (_filterIndex >= DC_FITER_SIZE)
{
_filterIndex = 0;
}
return((float)_lpf.DoSample(sample));
}