BizHawk/BizHawk.Emulation/Consoles/Atari/2600/Atari2600.Core.cs

298 lines
8.2 KiB
C#

using System;
using BizHawk.Emulation.CPUs.M6502;
using BizHawk.Emulation.Consoles.Atari;
using BizHawk.Emulation.Consoles.Atari._2600;
namespace BizHawk
{
partial class Atari2600
{
public byte[] rom;
public MOS6502X cpu;
public M6532 m6532;
public TIA tia;
public Emulation.Sound.Utilities.DCFilter dcfilter;
public byte[] ram = new byte[128];
public MapperBase mapper;
// The Atari 2600 memory mapper looks something like this...usually
// N/A Page #
// 000 0000000 000000
// 0x0000-0x003F - TIA Registers
// 0x0040-0x007F - TIA Registers (mirror)
// 0x0080-0x00FF - 6532 RAM
// 0x0100-0x01FF - Mirror of 0x00FF
// 0x0200-0x023F - TIA Registers (mirror)
// 0x0240-0x027F - TIA Registers (mirror)
// 0x0280-0x029F - 6532 Registers
// 0x02A0-0x02BF - 6532 Registers (mirror)
// 0x02C0-0x02DF - 6532 Registers (mirror)
// 0x02E0-0x02FF - 6532 Registers (mirror)
// 0x0300-0x033F - TIA Registers (mirror)
// 0x0340-0x037F - TIA Registers (mirror)
// 0x0380-0x039F - 6532 Registers (mirror)
// 0x03A0-0x03BF - 6532 Registers (mirror)
// 0x03C0-0x03DF - 6532 Registers (mirror)
// 0x03E0-0x03FF - 6532 Registers (mirror)
// 0x0400-0x07FF - Mirror of 0x0000-0x03FF
// 0x0800-0x0BFF - Mirror of 0x0000-0x03FF
// 0x0C00-0x0FFF - Mirror of 0x0000-0x03FF
// 0x1000-0x1FFF - ROM
// If page# % 4 == 0 or 1, TIA
// If page# % 4 == 2 or 3, 6532
// if (addr & 0x0200 == 0x0000 && addr & 0x1080 == 0x0080)
// RAM
// else
// registers
// else
// ROM
public byte BaseReadMemory(ushort addr)
{
addr = (ushort)(addr & 0x1FFF);
if ((addr & 0x1080) == 0)
{
return tia.ReadMemory(addr, false);
}
else if ((addr & 0x1080) == 0x0080)
{
return m6532.ReadMemory(addr, false);
}
else
{
return rom[addr & 0x0FFF];
}
}
public byte BasePeekMemory(ushort addr)
{
addr = (ushort)(addr & 0x1FFF);
if ((addr & 0x1080) == 0)
{
return tia.ReadMemory(addr, true);
}
else if ((addr & 0x1080) == 0x0080)
{
return m6532.ReadMemory(addr, true);
}
else
{
return rom[addr & 0x0FFF];
}
}
public void BaseWriteMemory(ushort addr, byte value)
{
addr = (ushort)(addr & 0x1FFF);
if ((addr & 0x1080) == 0)
{
tia.WriteMemory(addr, value);
}
else if ((addr & 0x1080) == 0x0080)
{
m6532.WriteMemory(addr, value);
}
else
{
Console.WriteLine("ROM write(?): " + addr.ToString("x"));
}
}
public byte ReadMemory(ushort addr)
{
byte temp = mapper.ReadMemory((ushort)(addr&0x1FFF));
if (CoreComm.MemoryCallbackSystem.HasRead)
{
CoreComm.MemoryCallbackSystem.TriggerRead(addr);
}
return temp;
}
public byte PeekMemory(ushort addr)
{
byte temp = mapper.ReadMemory((ushort)(addr & 0x1FFF));
return temp;
}
public void WriteMemory(ushort addr, byte value)
{
mapper.WriteMemory((ushort)(addr & 0x1FFF), value);
if (CoreComm.MemoryCallbackSystem.HasWrite)
{
CoreComm.MemoryCallbackSystem.TriggerWrite(addr);
}
}
public void HardReset()
{
//regenerate mapper here to make sure its state is entirely clean
switch (game.GetOptionsDict()["m"])
{
case "4K": mapper = new m4K(); break;
case "2K": mapper = new m2K(); break;
case "CV": mapper = new mCV(); break;
case "F8": mapper = new mF8(); break;
case "F6":
case "4IN1":
case "F6SC": mapper = new mF6(); break;
case "F4":
case "F4SC": mapper = new mF4(); break;
case "FE": mapper = new mFE(); break;
case "E0": mapper = new mE0(); break;
case "3F": mapper = new m3F(); break;
case "FA": mapper = new mFA(); break;
case "E7": mapper = new mE7(); break;
case "F0": mapper = new mF0(); break;
case "UA": mapper = new mUA(); break;
//Homebrew mappers
case "3Fe": mapper = new m3Fe(); break;
case "3E": mapper = new m3E(); break;
case "0840": mapper = new m0840(); break;
case "MC": mapper = new mMC(); break;
case "EF": mapper = new mEF(); break;
case "X07": mapper = new mX07(); break;
case "4A50": mapper = new m4A50(); break;
case "DPC": mapper = new mDPC(); break;
default: throw new InvalidOperationException("mapper not supported: " + game.GetOptionsDict()["m"]);
}
mapper.core = this;
_lagcount = 0;
cpu = new MOS6502X();
//cpu.debug = true;
cpu.ReadMemory = ReadMemory;
cpu.WriteMemory = WriteMemory;
cpu.PeekMemory = PeekMemory;
cpu.DummyReadMemory = ReadMemory;
// Setup TIA
//tia = new TIA(this, frameBuffer);
tia = new TIA(this);
// dcfilter coefficent is from real observed hardware behavior: a latched "1" will fully decay by ~170 or so tia sound cycles
dcfilter = Emulation.Sound.Utilities.DCFilter.AsISoundProvider(tia, 256);
// Setup 6532
m6532 = new M6532(this);
//setup the system state here. for instance..
// Read from the reset vector for where to start
cpu.PC = (ushort)(ReadMemory(0x1FFC) + (ReadMemory(0x1FFD) << 8)); //set the initial PC
//cpu.PC = 0x0000; //set the initial PC
// show mapper class on romstatusdetails
CoreComm.RomStatusDetails =
string.Format("{0}\r\nSHA1:{1}\r\nMD5:{2}\r\nMapper Impl \"{3}\"",
game.Name,
Util.BytesToHexString(System.Security.Cryptography.SHA1.Create().ComputeHash(rom)),
Util.BytesToHexString(System.Security.Cryptography.MD5.Create().ComputeHash(rom)),
mapper.GetType().ToString());
}
public void FrameAdvance(bool render, bool rendersound)
{
_frame++;
_islag = true;
tia.frameComplete = false;
while (tia.frameComplete == false)
{
tia.execute(1);
tia.execute(1);
tia.execute(1);
m6532.timer.tick();
if (CoreComm.Tracer.Enabled)
CoreComm.Tracer.Put(cpu.TraceState());
cpu.ExecuteOne();
//if (cpu.PendingCycles <= 0)
//{
// //Console.WriteLine("Tia clocks: " + tia.scanlinePos + " CPU pending: " + cpu.PendingCycles);
//}
//if (cpu.PendingCycles < 0)
//{
// Console.WriteLine("------------Something went wrong------------");
//}
}
if (_islag)
LagCount++;
//if (render == false) return;
}
public byte ReadControls1(bool peek)
{
if (CoreComm.InputCallback != null) CoreComm.InputCallback();
byte value = 0xFF;
if (Controller["P1 Up"]) value &= 0xEF;
if (Controller["P1 Down"]) value &= 0xDF;
if (Controller["P1 Left"]) value &= 0xBF;
if (Controller["P1 Right"]) value &= 0x7F;
if (Controller["P1 Button"]) value &= 0xF7;
if(!peek) _islag = false;
return value;
}
public byte ReadControls2(bool peek)
{
if (CoreComm.InputCallback != null) CoreComm.InputCallback();
byte value = 0xFF;
if (Controller["P2 Up"]) value &= 0xEF;
if (Controller["P2 Down"]) value &= 0xDF;
if (Controller["P2 Left"]) value &= 0xBF;
if (Controller["P2 Right"]) value &= 0x7F;
if (Controller["P2 Button"]) value &= 0xF7;
if (!peek) _islag = false;
return value;
}
private bool bw = false;
private bool p0difficulty = true;
private bool p1difficulty = true;
public void SetBw(bool setting) { bw = setting; }
public void SetP0Diff(bool setting) { p0difficulty = setting; }
public void SetP1Diff(bool setting) { p1difficulty = setting; }
public byte ReadConsoleSwitches(bool peek)
{
//TODO - zeromus isnt sure this should clear the lag flag
byte value = 0xFF;
bool select = Controller["Select"];
bool reset = Controller["Reset"];
if (reset) value &= 0xFE;
if (select) value &= 0xFD;
if (bw) value &= 0xF7;
if (p0difficulty) value &= 0xBF;
if (p1difficulty) value &= 0x7F;
if(!peek) _islag = false;
return value;
}
}
public class MapperBase
{
public Atari2600 core;
public virtual byte ReadMemory(ushort addr) { return core.BaseReadMemory(addr); }
public virtual byte PeekMemory(ushort addr) { return core.BasePeekMemory(addr); }
public virtual void WriteMemory(ushort addr, byte value) { core.BaseWriteMemory(addr, value); }
public virtual void SyncState(Serializer ser) { }
public virtual void Dispose() { }
}
}