From d44971a021190a27dc467e1e1ae0b0f718e5b666 Mon Sep 17 00:00:00 2001
From: alyosha-tas <alexei.f.k@gmail.com>
Date: Fri, 21 Jul 2017 16:34:27 -0400
Subject: [PATCH] Atari7800Hawk: More Mappers

---
 .../Atari/A7800Hawk/Mappers/MapperSG.cs       |  30 +++--
 .../Atari/A7800Hawk/Mappers/MapperSGE.cs      | 113 ++++++++++++++++++
 2 files changed, 135 insertions(+), 8 deletions(-)
 create mode 100644 BizHawk.Emulation.Cores/Consoles/Atari/A7800Hawk/Mappers/MapperSGE.cs

diff --git a/BizHawk.Emulation.Cores/Consoles/Atari/A7800Hawk/Mappers/MapperSG.cs b/BizHawk.Emulation.Cores/Consoles/Atari/A7800Hawk/Mappers/MapperSG.cs
index 9337faa364..45e68c1099 100644
--- a/BizHawk.Emulation.Cores/Consoles/Atari/A7800Hawk/Mappers/MapperSG.cs
+++ b/BizHawk.Emulation.Cores/Consoles/Atari/A7800Hawk/Mappers/MapperSG.cs
@@ -4,8 +4,7 @@ using System;
 
 namespace BizHawk.Emulation.Cores.Atari.A7800Hawk
 {
-	// Default mapper with no bank switching
-	// Just need to keep track of high score bios stuff
+	// Default Bank Switching Mapper used by most games
 	public class MapperSG : MapperBase
 	{
 		public byte bank = 0;
@@ -42,24 +41,39 @@ namespace BizHawk.Emulation.Cores.Atari.A7800Hawk
 				}
 				else
 				{
-					if (addr >=0xC000)
+					if (addr >= 0xC000)
 					{
 						// bank 7 is fixed
 						return Core._rom[Core._rom.Length - (0x10000 - addr)];
 					}
 					else if (addr >= 0x8000)
 					{
-						// reutrn whatever bank is there
+						// return whatever bank is there
 						int temp_addr = addr - 0x8000;
-
 						return Core._rom[temp_addr + bank * 0x4000];
 					}
 					else
 					{
 						// return bank 6
 						int temp_addr = addr - 0x4000;
-						return Core._rom[temp_addr + 6 * 0x4000];
-					}				
+
+						if (!Core.small_flag)
+						{
+							return Core._rom[temp_addr + 6 * 0x4000];					
+						}
+						else
+						{
+							if (Core.PAL_Kara)
+							{
+								return Core._rom[temp_addr + 2 * 0x4000];
+							}
+							else
+							{
+								// Should never get here, but in case we do just return FF
+								return 0xFF;
+							}
+						}
+					}			
 				}
 			}
 		}
@@ -95,7 +109,7 @@ namespace BizHawk.Emulation.Cores.Atari.A7800Hawk
 				// cartridge and other OPSYS
 				if (addr>=0x8000)
 				{
-					bank = (byte)(value & 0x7);
+					bank = (byte)(value & (Core.small_flag ? 0x3 : 0x7));
 				}
 			}
 		}
diff --git a/BizHawk.Emulation.Cores/Consoles/Atari/A7800Hawk/Mappers/MapperSGE.cs b/BizHawk.Emulation.Cores/Consoles/Atari/A7800Hawk/Mappers/MapperSGE.cs
new file mode 100644
index 0000000000..a3f5f47e98
--- /dev/null
+++ b/BizHawk.Emulation.Cores/Consoles/Atari/A7800Hawk/Mappers/MapperSGE.cs
@@ -0,0 +1,113 @@
+using BizHawk.Common;
+using BizHawk.Common.NumberExtensions;
+using System;
+
+namespace BizHawk.Emulation.Cores.Atari.A7800Hawk
+{
+	// Super Game mapper but with extra ROM at the start of the file
+	// Have to add 1 to bank number to get correct bank value
+	public class MapperSGE : MapperBase
+	{
+		public byte bank = 0;
+
+		public override byte ReadMemory(ushort addr)
+		{
+			if (addr >= 0x1000 && addr < 0x1800)
+			{
+				//could be hsbios RAM here
+				if (Core._hsbios != null)
+				{
+					return Core._hsram[addr - 0x1000];
+				}
+				return 0xFF;
+			}
+			else if (addr < 0x4000)
+			{
+				// could be either RAM mirror or ROM
+				if (addr >= 0x3000 && Core._hsbios != null)
+				{
+					return Core._hsbios[addr - 0x3000];
+				}
+				else
+				{
+					return Core.RAM[0x800 + addr & 0x7FF];
+				}
+			}
+			else
+			{
+				// cartridge and other OPSYS
+				if (addr >= (0x10000 - Core._bios.Length) && !Core.A7800_control_register.Bit(2))
+				{
+					return Core._bios[addr - (0x10000 - Core._bios.Length)];
+				}
+				else
+				{
+					if (addr >=0xC000)
+					{
+						// bank 7 is fixed
+						return Core._rom[Core._rom.Length - (0x10000 - addr)];
+					}
+					else if (addr >= 0x8000)
+					{
+						// return whatever bank is there
+						// but remember we need to add 1 to adjust for the extra bank at the beginning
+						int temp_addr = addr - 0x8000;
+						return Core._rom[temp_addr + (bank + 1) * 0x4000];
+					}
+					else
+					{
+						// return the 16k extra ROM (located at beginning of file)
+						int temp_addr = addr - 0x4000;
+						return Core._rom[temp_addr];
+					}				
+				}
+			}
+		}
+
+		public override byte PeekMemory(ushort addr)
+		{
+			return ReadMemory(addr);
+		}
+
+		public override void WriteMemory(ushort addr, byte value)
+		{
+			if (addr >= 0x1000 && addr < 0x1800)
+			{
+				//could be hsbios RAM here
+				if (Core._hsbios != null)
+				{
+					Core._hsram[addr - 0x1000] = value;
+				}
+			}
+			else if (addr < 0x4000)
+			{
+				// could be either RAM mirror or ROM
+				if (addr >= 0x3000 && Core._hsbios != null)
+				{
+				}
+				else
+				{
+					Core.RAM[0x800 + addr & 0x7FF] = value;
+				}
+			}
+			else
+			{
+				// cartridge and other OPSYS
+				if (addr>=0x8000)
+				{
+					bank = (byte)(value & 0x7);
+				}
+			}
+		}
+
+		public override void PokeMemory(ushort addr, byte value)
+		{
+			WriteMemory(addr, value);
+		}
+
+		public override void SyncState(Serializer ser)
+		{
+			ser.Sync("Bank", ref bank);
+		}
+	}
+}