AxibugEmuOnline/AxibugEmuOnline.Client/Assets/MyNes.Core/FFE.cs
2024-07-03 18:22:22 +08:00

57 lines
1.2 KiB
C#

using System.IO;
namespace MyNes.Core
{
internal abstract class FFE : Board
{
protected bool irqEnable;
protected int irqCounter;
internal override void WriteEX(ref ushort address, ref byte data)
{
switch (address)
{
case 17665:
irqEnable = false;
NesEmu.IRQFlags &= -9;
break;
case 17666:
irqCounter = (irqCounter & 0xFF00) | data;
break;
case 17667:
irqEnable = true;
irqCounter = (irqCounter & 0xFF) | (data << 8);
break;
}
}
internal override void OnCPUClock()
{
if (irqEnable)
{
irqCounter++;
if (irqCounter >= 65535)
{
irqCounter = 0;
NesEmu.IRQFlags |= 8;
}
}
}
internal override void WriteStateData(ref BinaryWriter bin)
{
base.WriteStateData(ref bin);
bin.Write(irqEnable);
bin.Write(irqCounter);
}
internal override void ReadStateData(ref BinaryReader bin)
{
base.ReadStateData(ref bin);
irqEnable = bin.ReadBoolean();
irqCounter = bin.ReadInt32();
}
}
}