Exemple #1
0
 /// <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();
 }
Exemple #2
0
        /// <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));
        }