255 lines
6.5 KiB
C#
255 lines
6.5 KiB
C#
using System.IO;
|
|
|
|
namespace MyNes.Core
|
|
{
|
|
[BoardInfo("VRC4", 25)]
|
|
internal class Mapper025 : Board
|
|
{
|
|
private bool prg_mode;
|
|
|
|
private byte prg_reg0;
|
|
|
|
private int[] chr_Reg;
|
|
|
|
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 void HardReset()
|
|
{
|
|
base.HardReset();
|
|
Switch16KPRG(PRG_ROM_16KB_Mask, PRGArea.AreaC000);
|
|
prescaler = 341;
|
|
chr_Reg = new int[8];
|
|
}
|
|
|
|
internal override void WritePRG(ref ushort address, ref byte data)
|
|
{
|
|
switch (address)
|
|
{
|
|
case 32768:
|
|
case 32769:
|
|
case 32770:
|
|
case 32771:
|
|
case 32772:
|
|
case 32776:
|
|
case 32780:
|
|
prg_reg0 = data;
|
|
Switch08KPRG(prg_mode ? (PRG_ROM_08KB_Mask - 1) : (prg_reg0 & 0x1F), PRGArea.Area8000);
|
|
Switch08KPRG(prg_mode ? (prg_reg0 & 0x1F) : (PRG_ROM_08KB_Mask - 1), PRGArea.AreaC000);
|
|
break;
|
|
case 36864:
|
|
case 36866:
|
|
case 36872:
|
|
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 36865:
|
|
case 36867:
|
|
case 36868:
|
|
case 36876:
|
|
prg_mode = (data & 2) == 2;
|
|
Switch08KPRG(prg_mode ? (PRG_ROM_08KB_Mask - 1) : (prg_reg0 & 0x1F), PRGArea.Area8000);
|
|
Switch08KPRG(prg_mode ? (prg_reg0 & 0x1F) : (PRG_ROM_08KB_Mask - 1), PRGArea.AreaC000);
|
|
break;
|
|
case 40960:
|
|
case 40961:
|
|
case 40962:
|
|
case 40963:
|
|
case 40964:
|
|
case 40968:
|
|
case 40972:
|
|
Switch08KPRG(data & 0x1F, PRGArea.AreaA000);
|
|
break;
|
|
case 45056:
|
|
chr_Reg[0] = (chr_Reg[0] & 0xF0) | (data & 0xF);
|
|
Switch01KCHR(chr_Reg[0], CHRArea.Area0000);
|
|
break;
|
|
case 45058:
|
|
case 45064:
|
|
chr_Reg[0] = (chr_Reg[0] & 0xF) | ((data & 0xF) << 4);
|
|
Switch01KCHR(chr_Reg[0], CHRArea.Area0000);
|
|
break;
|
|
case 45057:
|
|
case 45060:
|
|
chr_Reg[1] = (chr_Reg[1] & 0xF0) | (data & 0xF);
|
|
Switch01KCHR(chr_Reg[1], CHRArea.Area0400);
|
|
break;
|
|
case 45059:
|
|
case 45068:
|
|
chr_Reg[1] = (chr_Reg[1] & 0xF) | ((data & 0xF) << 4);
|
|
Switch01KCHR(chr_Reg[1], CHRArea.Area0400);
|
|
break;
|
|
case 49152:
|
|
chr_Reg[2] = (chr_Reg[2] & 0xF0) | (data & 0xF);
|
|
Switch01KCHR(chr_Reg[2], CHRArea.Area0800);
|
|
break;
|
|
case 49154:
|
|
case 49160:
|
|
chr_Reg[2] = (chr_Reg[2] & 0xF) | ((data & 0xF) << 4);
|
|
Switch01KCHR(chr_Reg[2], CHRArea.Area0800);
|
|
break;
|
|
case 49153:
|
|
case 49156:
|
|
chr_Reg[3] = (chr_Reg[3] & 0xF0) | (data & 0xF);
|
|
Switch01KCHR(chr_Reg[3], CHRArea.Area0C00);
|
|
break;
|
|
case 49155:
|
|
case 49164:
|
|
chr_Reg[3] = (chr_Reg[3] & 0xF) | ((data & 0xF) << 4);
|
|
Switch01KCHR(chr_Reg[3], CHRArea.Area0C00);
|
|
break;
|
|
case 53248:
|
|
chr_Reg[4] = (chr_Reg[4] & 0xF0) | (data & 0xF);
|
|
Switch01KCHR(chr_Reg[4], CHRArea.Area1000);
|
|
break;
|
|
case 53250:
|
|
case 53256:
|
|
chr_Reg[4] = (chr_Reg[4] & 0xF) | ((data & 0xF) << 4);
|
|
Switch01KCHR(chr_Reg[4], CHRArea.Area1000);
|
|
break;
|
|
case 53249:
|
|
case 53252:
|
|
chr_Reg[5] = (chr_Reg[5] & 0xF0) | (data & 0xF);
|
|
Switch01KCHR(chr_Reg[5], CHRArea.Area1400);
|
|
break;
|
|
case 53251:
|
|
case 53260:
|
|
chr_Reg[5] = (chr_Reg[5] & 0xF) | ((data & 0xF) << 4);
|
|
Switch01KCHR(chr_Reg[5], CHRArea.Area1400);
|
|
break;
|
|
case 57344:
|
|
chr_Reg[6] = (chr_Reg[6] & 0xF0) | (data & 0xF);
|
|
Switch01KCHR(chr_Reg[6], CHRArea.Area1800);
|
|
break;
|
|
case 57346:
|
|
case 57352:
|
|
chr_Reg[6] = (chr_Reg[6] & 0xF) | ((data & 0xF) << 4);
|
|
Switch01KCHR(chr_Reg[6], CHRArea.Area1800);
|
|
break;
|
|
case 57345:
|
|
case 57348:
|
|
chr_Reg[7] = (chr_Reg[7] & 0xF0) | (data & 0xF);
|
|
Switch01KCHR(chr_Reg[7], CHRArea.Area1C00);
|
|
break;
|
|
case 57347:
|
|
case 57356:
|
|
chr_Reg[7] = (chr_Reg[7] & 0xF) | ((data & 0xF) << 4);
|
|
Switch01KCHR(chr_Reg[7], CHRArea.Area1C00);
|
|
break;
|
|
case 61440:
|
|
irq_reload = (irq_reload & 0xF0) | (data & 0xF);
|
|
break;
|
|
case 61442:
|
|
case 61448:
|
|
irq_reload = (irq_reload & 0xF) | ((data & 0xF) << 4);
|
|
break;
|
|
case 61441:
|
|
case 61444:
|
|
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 61443:
|
|
case 61452:
|
|
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(prg_mode);
|
|
stream.Write(prg_reg0);
|
|
for (int i = 0; i < chr_Reg.Length; i++)
|
|
{
|
|
stream.Write(chr_Reg[i]);
|
|
}
|
|
stream.Write(irq_reload);
|
|
stream.Write(irq_counter);
|
|
stream.Write(prescaler);
|
|
stream.Write(irq_mode_cycle);
|
|
stream.Write(irq_enable);
|
|
stream.Write(irq_enable_on_ak);
|
|
}
|
|
|
|
internal override void ReadStateData(ref BinaryReader stream)
|
|
{
|
|
base.ReadStateData(ref stream);
|
|
prg_mode = stream.ReadBoolean();
|
|
prg_reg0 = stream.ReadByte();
|
|
for (int i = 0; i < chr_Reg.Length; i++)
|
|
{
|
|
chr_Reg[i] = stream.ReadInt32();
|
|
}
|
|
irq_reload = stream.ReadInt32();
|
|
irq_counter = stream.ReadInt32();
|
|
prescaler = stream.ReadInt32();
|
|
irq_mode_cycle = stream.ReadBoolean();
|
|
irq_enable = stream.ReadBoolean();
|
|
irq_enable_on_ak = stream.ReadBoolean();
|
|
}
|
|
}
|
|
}
|