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Rewrite audio routines 

Now samples sound explicitly at proper points each scanline.
Sounds the same (i.e. sometimes wrong) as before, so other bugs exist.
WIP
This commit is contained in:
alyosha-tas 2016-06-04 18:32:26 -04:00
parent f60dde19f5
commit d7436554b8
1 changed files with 21 additions and 66 deletions
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87
BizHawk.Emulation.Cores/Consoles/Atari/2600/Tia/TIA.cs
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@ -318,7 +318,7 @@ namespace BizHawk.Emulation.Cores.Atari.Atari2600
private bool _vblankEnabled;
private bool _vsyncEnabled;
private int _CurrentScanLine;
private int _audioClocks; // not savestated
public int _audioClocks; // not savestated
private PlayerData _player0;
private PlayerData _player1;
@ -328,6 +328,10 @@ namespace BizHawk.Emulation.Cores.Atari.Atari2600
public Audio[] AUD = { new Audio(), new Audio() };
// current audio register state used to sample correct positions in the scanline (clrclk 0 and 114)
//public byte[] current_audio_register = new byte[6];
public short[] _local_audio_cycles = new short[2000];
public TIA(Atari2600 core, bool pal, bool secam)
{
_core = core;
@ -1030,7 +1034,13 @@ namespace BizHawk.Emulation.Cores.Atari.Atari2600
}
// do the audio sampling
if (_hsyncCnt==36 || _hsyncCnt==148)
{
_local_audio_cycles[_audioClocks] += (short)(AUD[0].Cycle()/2);
_local_audio_cycles[_audioClocks] += (short)(AUD[1].Cycle()/2);
_audioClocks++;
}
// Increment the hsync counter
_hsyncCnt++;
@ -1042,7 +1052,6 @@ namespace BizHawk.Emulation.Cores.Atari.Atari2600
_hmove.LateHBlankReset = false;
_CurrentScanLine++;
LineCount++;
_audioClocks += 2; // TODO: increment this at the appropriate places twice per line
}
}
@ -1429,27 +1438,27 @@ namespace BizHawk.Emulation.Cores.Atari.Atari2600
}
else if (maskedAddr == 0x15) // AUDC0
{
WriteAudio(0, AudioRegister.AUDC, (byte)(value & 15));
AUD[0].AUDC= (byte)(value & 15);
}
else if (maskedAddr == 0x16) // AUDC1
{
WriteAudio(1, AudioRegister.AUDC, (byte)(value & 15));
AUD[1].AUDC = (byte)(value & 15);
}
else if (maskedAddr == 0x17) // AUDF0
{
WriteAudio(0, AudioRegister.AUDF, (byte)((value & 31) + 1));
AUD[0].AUDF = (byte)((value & 31) + 1);
}
else if (maskedAddr == 0x18) // AUDF1
{
WriteAudio(1, AudioRegister.AUDF, (byte)((value & 31) + 1));
AUD[1].AUDF = (byte)((value & 31) + 1);
}
else if (maskedAddr == 0x19) // AUDV0
{
WriteAudio(0, AudioRegister.AUDV, (byte)(value & 15));
AUD[0].AUDV = (byte)(value & 15);
}
else if (maskedAddr == 0x1A) // AUDV1
{
WriteAudio(1, AudioRegister.AUDV, (byte)(value & 15));
AUD[1].AUDV = (byte)(value & 15);
}
else if (maskedAddr == 0x1B) // GRP0
{
@ -1557,16 +1566,8 @@ namespace BizHawk.Emulation.Cores.Atari.Atari2600
#region Audio bits
private enum AudioRegister : byte { AUDC, AUDF, AUDV }
private struct QueuedCommand
{
public int Time;
public byte Channel;
public AudioRegister Register;
public byte Value;
}
private int frameStartCycles, frameEndCycles;
private Queue<QueuedCommand> commands = new Queue<QueuedCommand>(4096);
public void BeginAudioFrame()
{
@ -1578,54 +1579,18 @@ namespace BizHawk.Emulation.Cores.Atari.Atari2600
frameEndCycles = _core.Cpu.TotalExecutedCycles;
}
private void WriteAudio(byte channel, AudioRegister register, byte value)
{
commands.Enqueue(new QueuedCommand { Channel = channel, Register = register, Value = value, Time = _core.Cpu.TotalExecutedCycles - frameStartCycles });
}
private void ApplyAudioCommand(QueuedCommand cmd)
{
switch (cmd.Register)
{
case AudioRegister.AUDC:
AUD[cmd.Channel].AUDC = cmd.Value;
break;
case AudioRegister.AUDF:
AUD[cmd.Channel].AUDF = cmd.Value;
break;
case AudioRegister.AUDV:
AUD[cmd.Channel].AUDV = cmd.Value;
break;
}
}
// TODO: more accurate would be to have audio.Cycle() occur at
// the explicit exact times in the scanline, instead of just approximately spaced
public void GetSamples(short[] samples)
{
if (_audioClocks > 0)
{
var samples31khz = new short[_audioClocks]; // mono
int elapsedCycles = frameEndCycles - frameStartCycles;
if (elapsedCycles == 0)
for (int i=0;i<_audioClocks;i++)
{
elapsedCycles = 1; // better than diving by zero
samples31khz[i] = _local_audio_cycles[i];
_local_audio_cycles[i] = 0;
}
int start = 0;
while (commands.Count > 0)
{
var cmd = commands.Dequeue();
int pos = (cmd.Time * samples31khz.Length) / elapsedCycles;
pos = Math.Min(pos, samples31khz.Length); // sometimes the cpu timestamp of the write is > frameEndCycles
GetSamplesImmediate(samples31khz, start, pos - start);
start = pos;
ApplyAudioCommand(cmd);
}
GetSamplesImmediate(samples31khz, start, samples31khz.Length - start);
// convert from 31khz to 44khz
for (var i = 0; i < samples.Length / 2; i++)
{
@ -1636,18 +1601,8 @@ namespace BizHawk.Emulation.Cores.Atari.Atari2600
_audioClocks = 0;
}
public void GetSamplesImmediate(short[] samples, int start, int len)
{
for (var i = start; i < start + len; i++)
{
samples[i] += AUD[0].Cycle();
samples[i] += AUD[1].Cycle();
}
}
public void DiscardSamples()
{
commands.Clear();
_audioClocks = 0;
}