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2600: 'cycle accurate' audio, fix pitfall2 music

This commit is contained in:
beirich 2014-04-10 03:30:46 +00:00
parent 29475fb24d
commit 860483934f
2 changed files with 95 additions and 28 deletions
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2
BizHawk.Emulation.Cores/Consoles/Atari/2600/Atari2600.Core.cs
View File

@ -279,6 +279,7 @@ namespace BizHawk.Emulation.Cores.Atari.Atari2600
_frame++;
_islag = true;
_tia.FrameComplete = false;
_tia.BeginAudioFrame();
while (_tia.FrameComplete == false)
{
_tia.Execute(1);
@ -294,6 +295,7 @@ namespace BizHawk.Emulation.Cores.Atari.Atari2600
Cpu.ExecuteOne();
_mapper.ClockCpu();
}
_tia.CompleteAudioFrame();
if (_hardResetSignal)
{

121
BizHawk.Emulation.Cores/Consoles/Atari/2600/Tia/TIA.cs
View File

@ -1,5 +1,5 @@
using System.Collections.Generic;
using System;
using System.Collections.Generic;
using BizHawk.Common;
using BizHawk.Emulation.Common;
@ -123,26 +123,6 @@ namespace BizHawk.Emulation.Cores.Atari.Atari2600
return FrameBuffer;
}
public void GetSamples(short[] samples)
{
var moreSamples = new short[523];
for (int i = 0; i < moreSamples.Length; i++)
{
for (int snd = 0; snd < 2; snd++)
{
moreSamples[i] += AUD[snd].Cycle();
}
}
for (int i = 0; i < samples.Length / 2; i++)
{
samples[i * 2] = moreSamples[(int)(((double)moreSamples.Length / (double)(samples.Length / 2)) * i)];
samples[(i * 2) + 1] = samples[i * 2];
}
}
public void DiscardSamples() { }
// Execute TIA cycles
public void Execute(int cycles)
{
@ -736,27 +716,27 @@ namespace BizHawk.Emulation.Cores.Atari.Atari2600
}
else if (maskedAddr == 0x15) // AUDC0
{
AUD[0].AUDC = (byte)(value & 15);
WriteAudio(0, AudioRegister.AUDC, (byte)(value & 15));
}
else if (maskedAddr == 0x16) // AUDC1
{
AUD[1].AUDC = (byte)(value & 15);
WriteAudio(1, AudioRegister.AUDC, (byte)(value & 15));
}
else if (maskedAddr == 0x17) // AUDF0
{
AUD[0].AUDF = (byte)((value & 31) + 1);
WriteAudio(0, AudioRegister.AUDF, (byte)((value & 31) + 1));
}
else if (maskedAddr == 0x18) // AUDF1
{
AUD[1].AUDF = (byte)((value & 31) + 1);
WriteAudio(1, AudioRegister.AUDF, (byte)((value & 31) + 1));
}
else if (maskedAddr == 0x19) // AUDV0
{
AUD[0].AUDV = (byte)(value & 15);
WriteAudio(0, AudioRegister.AUDV, (byte)(value & 15));
}
else if (maskedAddr == 0x1A) // AUDV1
{
AUD[1].AUDV = (byte)(value & 15);
WriteAudio(1, AudioRegister.AUDV, (byte)(value & 15));
}
else if (maskedAddr == 0x1B) // GRP0
{
@ -858,6 +838,91 @@ namespace BizHawk.Emulation.Cores.Atari.Atari2600
return result;
}
// =========================================================================
// Audio bits
// =========================================================================
enum AudioRegister : byte { AUDC, AUDF, AUDV }
struct QueuedCommand
{
public int Time;
public byte Channel;
public AudioRegister Register;
public byte Value;
}
int frameStartCycles, frameEndCycles;
Queue<QueuedCommand> commands = new Queue<QueuedCommand>(4096);
public void BeginAudioFrame()
{
frameStartCycles = _core.Cpu.TotalExecutedCycles;
}
public void CompleteAudioFrame()
{
frameEndCycles = _core.Cpu.TotalExecutedCycles;
}
void WriteAudio(byte channel, AudioRegister register, byte value)
{
commands.Enqueue(new QueuedCommand { Channel = channel, Register = register, Value = value, Time = _core.Cpu.TotalExecutedCycles - frameStartCycles });
}
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;
}
}
public void GetSamples(short[] samples)
{
var samples31khz = new short[((samples.Length / 2) * 31380) / 44100];
int elapsedCycles = frameEndCycles - frameStartCycles;
if (elapsedCycles == 0)
elapsedCycles = 1; // better than diving by zero
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 (int i = 0; i < samples.Length / 2; i++)
{
samples[i * 2] = samples31khz[(int)(((double)samples31khz.Length / (double)(samples.Length / 2)) * i)];
samples[(i * 2) + 1] = samples[i * 2];
}
}
public void GetSamplesImmediate(short[] samples, int start, int len)
{
for (int i = start; i < start + len; i++)
{
samples[i] += AUD[0].Cycle();
samples[i] += AUD[1].Cycle();
}
}
public void DiscardSamples()
{
commands.Clear();
}
// =========================================================================
public void SyncState(Serializer ser)
{
ser.BeginSection("TIA");