From 617f5ead2300dc42ad0c3f835641fa9994e09174 Mon Sep 17 00:00:00 2001
From: Souryo <mesenemu@gmail.com>
Date: Tue, 24 Jun 2014 14:28:19 -0400
Subject: [PATCH] CNROM (iNES mapper 3) support

---
 Core/BaseMapper.h         | 42 ---------------------------------------
 Core/CNROM.h              | 22 ++++++++++++++++++++
 Core/Core.vcxproj         |  3 +++
 Core/Core.vcxproj.filters |  9 +++++++++
 Core/MapperFactory.h      | 10 +++++++---
 Core/NROM.h               | 23 +++++++++++++++++++++
 Core/UNROM.h              | 25 +++++++++++++++++++++++
 7 files changed, 89 insertions(+), 45 deletions(-)
 create mode 100644 Core/CNROM.h
 create mode 100644 Core/NROM.h
 create mode 100644 Core/UNROM.h

diff --git a/Core/BaseMapper.h b/Core/BaseMapper.h
index e5b0435f..3341b40b 100644
--- a/Core/BaseMapper.h
+++ b/Core/BaseMapper.h
@@ -154,46 +154,4 @@ class BaseMapper : public IMemoryHandler
 		{
 			_chrPages[AddrToCHRSlot(addr)][addr & (GetCHRPageSize() - 1)] = value;
 		}
-};
-
-class DefaultMapper : public BaseMapper
-{
-	protected:
-		virtual uint32_t GetPRGPageSize() { return 0x4000; }
-		virtual uint32_t GetCHRPageSize() {	return 0x2000; }
-
-		virtual void InitMapper()
-		{
-			if(_prgSize == 0x4000) {
-				SelectPRGPage(0, 0);
-				SelectPRGPage(1, 0);
-			} else {
-				SelectPRGPage(0, 0);
-				SelectPRGPage(1, 1);
-			}
-
-			SelectCHRPage(0, 0);
-		}
-};
-
-class Mapper2 : public BaseMapper
-{
-	protected:
-		virtual uint32_t GetPRGPageSize() { return 0x4000; }
-		virtual uint32_t GetCHRPageSize() {	return 0x2000; }
-
-		void InitMapper() 
-		{
-			//First and last PRG page
-			SelectPRGPage(0, 0);
-			SelectPRGPage(1, 0xFF);
-
-			SelectCHRPage(0, 0);
-		}
-
-	public:		
-		void WriteRAM(uint16_t addr, uint8_t value)
-		{
-			SelectPRGPage(0, value);
-		}
 };
\ No newline at end of file
diff --git a/Core/CNROM.h b/Core/CNROM.h
new file mode 100644
index 00000000..40f98ad4
--- /dev/null
+++ b/Core/CNROM.h
@@ -0,0 +1,22 @@
+#pragma once
+#include "stdafx.h"
+#include "BaseMapper.h"
+
+class CNROM : public BaseMapper
+{
+	protected:
+		virtual uint32_t GetPRGPageSize() { return 0x8000; }
+		virtual uint32_t GetCHRPageSize() {	return 0x2000; }
+
+		void InitMapper() 
+		{
+			SelectPRGPage(0, 0);
+			SelectCHRPage(0, 0);
+		}
+
+	public:		
+		void WriteRAM(uint16_t addr, uint8_t value)
+		{
+			SelectCHRPage(0, value);
+		}
+};
\ No newline at end of file
diff --git a/Core/Core.vcxproj b/Core/Core.vcxproj
index 8eb1c71e..d62dc15f 100644
--- a/Core/Core.vcxproj
+++ b/Core/Core.vcxproj
@@ -89,6 +89,7 @@
   <ItemGroup>
     <ClInclude Include="APU.h" />
     <ClInclude Include="BaseMapper.h" />
+    <ClInclude Include="CNROM.h" />
     <ClInclude Include="ControlManager.h" />
     <ClInclude Include="IAudioDevice.h" />
     <ClInclude Include="IControlDevice.h" />
@@ -108,12 +109,14 @@
     <ClInclude Include="Nes_Apu\Nes_Oscs.h" />
     <ClInclude Include="Nes_Apu\Nes_Vrc6.h" />
     <ClInclude Include="Nes_Apu\Nonlinear_Buffer.h" />
+    <ClInclude Include="NROM.h" />
     <ClInclude Include="PPU.h" />
     <ClInclude Include="CPU.h" />
     <ClInclude Include="MemoryManager.h" />
     <ClInclude Include="ROMLoader.h" />
     <ClInclude Include="stdafx.h" />
     <ClInclude Include="targetver.h" />
+    <ClInclude Include="UNROM.h" />
   </ItemGroup>
   <ItemGroup>
     <ClCompile Include="APU.cpp" />
diff --git a/Core/Core.vcxproj.filters b/Core/Core.vcxproj.filters
index 9cc48b89..c0b8427c 100644
--- a/Core/Core.vcxproj.filters
+++ b/Core/Core.vcxproj.filters
@@ -105,6 +105,15 @@
     <ClInclude Include="MMC1.h">
       <Filter>Header Files\Mappers</Filter>
     </ClInclude>
+    <ClInclude Include="NROM.h">
+      <Filter>Header Files\Mappers</Filter>
+    </ClInclude>
+    <ClInclude Include="CNROM.h">
+      <Filter>Header Files\Mappers</Filter>
+    </ClInclude>
+    <ClInclude Include="UNROM.h">
+      <Filter>Header Files\Mappers</Filter>
+    </ClInclude>
   </ItemGroup>
   <ItemGroup>
     <ClCompile Include="CPU.cpp">
diff --git a/Core/MapperFactory.h b/Core/MapperFactory.h
index 319394a4..bd43f4ae 100644
--- a/Core/MapperFactory.h
+++ b/Core/MapperFactory.h
@@ -1,6 +1,8 @@
 #include "stdafx.h"
-#include "BaseMapper.h"
+#include "NROM.h"
 #include "MMC1.h"
+#include "UNROM.h"
+#include "CNROM.h"
 #include "ROMLoader.h"
 
 class MapperFactory
@@ -14,9 +16,11 @@ class MapperFactory
 			
 			BaseMapper* mapper = nullptr;
 			switch(mapperID) {
-				case 0: mapper = new DefaultMapper(); break;
+				case 0: mapper = new NROM(); break;
 				case 1: mapper = new MMC1(); break;
-				case 2: mapper = new Mapper2(); break;
+				case 2: mapper = new UNROM(); break;
+				case 3: mapper = new CNROM(); break;
+				//case 4: mapper = new MMC3(); break;
 			}			
 
 			if(!mapper) {
diff --git a/Core/NROM.h b/Core/NROM.h
new file mode 100644
index 00000000..7657c53d
--- /dev/null
+++ b/Core/NROM.h
@@ -0,0 +1,23 @@
+#pragma once
+#include "stdafx.h"
+#include "BaseMapper.h"
+
+class NROM : public BaseMapper
+{
+	protected:
+		virtual uint32_t GetPRGPageSize() { return 0x4000; }
+		virtual uint32_t GetCHRPageSize() {	return 0x2000; }
+
+		virtual void InitMapper()
+		{
+			if(_prgSize == 0x4000) {
+				SelectPRGPage(0, 0);
+				SelectPRGPage(1, 0);
+			} else {
+				SelectPRGPage(0, 0);
+				SelectPRGPage(1, 1);
+			}
+
+			SelectCHRPage(0, 0);
+		}
+};
diff --git a/Core/UNROM.h b/Core/UNROM.h
new file mode 100644
index 00000000..e4e55d0c
--- /dev/null
+++ b/Core/UNROM.h
@@ -0,0 +1,25 @@
+#pragma once
+#include "stdafx.h"
+#include "BaseMapper.h"
+
+class UNROM : public BaseMapper
+{
+	protected:
+		virtual uint32_t GetPRGPageSize() { return 0x4000; }
+		virtual uint32_t GetCHRPageSize() {	return 0x2000; }
+
+		void InitMapper() 
+		{
+			//First and last PRG page
+			SelectPRGPage(0, 0);
+			SelectPRGPage(1, -1);
+
+			SelectCHRPage(0, 0);
+		}
+
+	public:		
+		void WriteRAM(uint16_t addr, uint8_t value)
+		{
+			SelectPRGPage(0, value);
+		}
+};
\ No newline at end of file