AxibugEmuOnline/OtherCore/MyNes.Standard2/MyNes.Core/VRC6Pulse.cs

117 lines
2.1 KiB
C#
Raw Normal View History

2024-07-24 15:03:33 +08:00
using System.IO;
namespace MyNes.Core
{
internal class VRC6Pulse
{
private int dutyForm;
private int dutyStep;
private bool enabled = true;
internal bool Outputable;
private bool mode;
private byte volume;
private int freqTimer;
private int frequency;
private int cycles;
internal int output;
internal void HardReset()
{
dutyForm = 0;
dutyStep = 15;
enabled = true;
mode = false;
output = 0;
}
internal void Write0(ref byte data)
{
mode = (data & 0x80) == 128;
dutyForm = (data & 0x70) >> 4;
volume = (byte)(data & 0xFu);
}
internal void Write1(ref byte data)
{
frequency = (frequency & 0xF00) | data;
}
internal void Write2(ref byte data)
{
frequency = (frequency & 0xFF) | ((data & 0xF) << 8);
enabled = (data & 0x80) == 128;
}
internal void ClockSingle()
{
if (--cycles > 0)
{
return;
}
cycles = (frequency << 1) + 2;
if (!enabled)
{
return;
}
if (mode)
{
output = volume;
return;
}
dutyStep--;
if (dutyStep < 0)
{
dutyStep = 15;
}
if (dutyStep <= dutyForm)
{
if (Outputable)
{
output = volume;
}
else
{
output = 0;
}
}
else
{
output = 0;
}
}
internal void SaveState(ref BinaryWriter stream)
{
stream.Write(dutyForm);
stream.Write(dutyStep);
stream.Write(enabled);
stream.Write(mode);
stream.Write(volume);
stream.Write(freqTimer);
stream.Write(frequency);
stream.Write(cycles);
}
internal void LoadState(ref BinaryReader stream)
{
dutyForm = stream.ReadInt32();
dutyStep = stream.ReadInt32();
enabled = stream.ReadBoolean();
mode = stream.ReadBoolean();
volume = stream.ReadByte();
freqTimer = stream.ReadInt32();
frequency = stream.ReadInt32();
cycles = stream.ReadInt32();
}
}
}