AxibugEmuOnline/OtherCore/MyNes.Standard2/MyNes.Core/Mapper085.cs

172 lines
3.8 KiB
C#

using System.IO;
namespace MyNes.Core
{
[BoardInfo("VRC7", 85)]
[HassIssues]
internal class Mapper085 : Board
{
private int irq_reload;
private int irq_counter;
private int prescaler;
private bool irq_mode_cycle;
private bool irq_enable;
private bool irq_enable_on_ak;
internal override string Issues => MNInterfaceLanguage.IssueMapper85;
internal override void HardReset()
{
base.HardReset();
Switch08KPRG(PRG_ROM_08KB_Mask, PRGArea.AreaE000);
irq_reload = 0;
prescaler = 341;
irq_counter = 0;
irq_mode_cycle = false;
irq_enable = false;
irq_enable_on_ak = false;
}
internal override void WritePRG(ref ushort address, ref byte data)
{
switch (address)
{
case 32768:
Switch08KPRG(data, PRGArea.Area8000);
break;
case 32776:
case 32784:
Switch08KPRG(data, PRGArea.AreaA000);
break;
case 36864:
Switch08KPRG(data, PRGArea.AreaC000);
break;
case 40960:
Switch01KCHR(data, CHRArea.Area0000);
break;
case 40968:
case 40976:
Switch01KCHR(data, CHRArea.Area0400);
break;
case 45056:
Switch01KCHR(data, CHRArea.Area0800);
break;
case 45064:
case 45072:
Switch01KCHR(data, CHRArea.Area0C00);
break;
case 49152:
Switch01KCHR(data, CHRArea.Area1000);
break;
case 49160:
case 49168:
Switch01KCHR(data, CHRArea.Area1400);
break;
case 53248:
Switch01KCHR(data, CHRArea.Area1800);
break;
case 53256:
case 53264:
Switch01KCHR(data, CHRArea.Area1C00);
break;
case 57344:
switch (data & 3)
{
case 0:
Switch01KNMTFromMirroring(Mirroring.Vert);
break;
case 1:
Switch01KNMTFromMirroring(Mirroring.Horz);
break;
case 2:
Switch01KNMTFromMirroring(Mirroring.OneScA);
break;
case 3:
Switch01KNMTFromMirroring(Mirroring.OneScB);
break;
}
break;
case 57352:
case 57360:
irq_reload = data;
break;
case 61440:
irq_mode_cycle = (data & 4) == 4;
irq_enable = (data & 2) == 2;
irq_enable_on_ak = (data & 1) == 1;
if (irq_enable)
{
irq_counter = irq_reload;
prescaler = 341;
}
NesEmu.IRQFlags &= -9;
break;
case 61448:
case 61456:
NesEmu.IRQFlags &= -9;
irq_enable = irq_enable_on_ak;
break;
}
}
internal override void OnCPUClock()
{
if (!irq_enable)
{
return;
}
if (!irq_mode_cycle)
{
if (prescaler > 0)
{
prescaler -= 3;
return;
}
prescaler = 341;
irq_counter++;
if (irq_counter == 255)
{
NesEmu.IRQFlags |= 8;
irq_counter = irq_reload;
}
}
else
{
irq_counter++;
if (irq_counter == 255)
{
NesEmu.IRQFlags |= 8;
irq_counter = irq_reload;
}
}
}
internal override void WriteStateData(ref BinaryWriter stream)
{
base.WriteStateData(ref stream);
stream.Write(prescaler);
stream.Write(irq_counter);
stream.Write(irq_mode_cycle);
stream.Write(irq_reload);
stream.Write(irq_enable);
stream.Write(irq_enable_on_ak);
}
internal override void ReadStateData(ref BinaryReader stream)
{
base.ReadStateData(ref stream);
prescaler = stream.ReadInt32();
irq_counter = stream.ReadInt32();
irq_mode_cycle = stream.ReadBoolean();
irq_reload = stream.ReadInt32();
irq_enable = stream.ReadBoolean();
irq_enable_on_ak = stream.ReadBoolean();
}
}
}