Added Mapper 7v1.1

2 files changed, 27 insertions, 6 deletions

diff --git a/README.md b/README.md
index cde3e67..7a30cf4 100644
--- a/README.md
+++ b/README.md
@@ -36,13 +36,13 @@ C++                              1              5             85            708
 ### *nix systems
 ```sh
 git clone --recursive https://github.com/Ta180m/BadNES && cd BadNES
-g++ main.cpp -o badnes -std=c++11 -lSDL2main -lSDL2
+g++ main.cpp -o badnes -std=c++11 -lSDL2main -lSDL2 -O3
 ```
 
 ### Windows
 ```sh
 git clone --recursive https://github.com/Ta180m/BadNES && cd BadNES
-g++ main.cpp -o badnes -std=c++11 -IC:\mingw\include\SDL2 -LC:\mingw\lib -w -Wl,-subsystem,windows -lmingw32 -lSDL2main -lSDL2
+g++ main.cpp -o badnes -std=c++11 -IC:\mingw\include\SDL2 -LC:\mingw\lib -w -Wl,-subsystem,windows -lmingw32 -lSDL2main -lSDL2 -O3
 ```
 
 ## Usage
@@ -72,7 +72,7 @@ I really like LaiNES: it's very minimal and compact — but it has several depen
 I'm working on it right now.
 
 ### What do you mean by "nearly complete"?
-I'll say it's complete once I finish implementing the APU, savestates, and maybe Mapper 7.
+I'll say it's complete once I finish implementing the APU and savestates.
 
 ## Credits
 Special thanks to [Andrea Orru](https://github.com/AndreaOrru) for creating [LaiNES](https://github.com/AndreaOrru/LaiNES), the emulator that this project derives much of its code from.
\ No newline at end of file
diff --git a/main.cpp b/main.cpp
index 1ba7550..6b58e16 100644
--- a/main.cpp
+++ b/main.cpp
@@ -36,7 +36,7 @@ namespace CPU {
 }
 namespace PPU {
 	enum Scanline  { VISIBLE, POST, NMI, PRE };
-	enum Mirroring { VERTICAL, HORIZONTAL };
+	enum Mirroring { VERTICAL, HORIZONTAL, ONE_SCREEN_HI, ONE_SCREEN_LO, FOUR_SCREEN };
 	struct Sprite { // Sprite buffer
 		// Index in OAM, X position, Y position, Tile index, Attributes, Tile data (low), Tile data (high)
 		u8 id, x, y, tile, attr, dataL, dataH;
@@ -146,8 +146,10 @@ class Mapper1 : public Mapper {
 		if (regs[0] & 0b10000) { map_chr<4>(0, regs[1]); map_chr<4>(1, regs[2]); } // 4KB CHR
 		else map_chr<8>(0, regs[1] >> 1); // 8KB CHR
 		switch (regs[0] & 0b11) { // Set mirroring
-			case 2: set_mirroring(PPU::VERTICAL);   break;
-			case 3: set_mirroring(PPU::HORIZONTAL); break;
+			case 0: set_mirroring(PPU::ONE_SCREEN_LO); break;
+			case 1: set_mirroring(PPU::ONE_SCREEN_HI); break;
+        	case 2: set_mirroring(PPU::VERTICAL);      break;
+        	case 3: set_mirroring(PPU::HORIZONTAL);    break;
 		}
 	}
 public:
@@ -258,6 +260,22 @@ public:
 		if (irqEnabled and irqCounter == 0)	CPU::set_irq();
 	}
 };
+class Mapper7 : public Mapper {
+    u8 regs[1];
+	// Apply the registers state
+    void apply() {
+    	map_prg<32>(0, regs[0] & 0b00001111); // 32 kb PRG ROM Banks, 0x8000 - 0xFFFF swappable
+    	map_chr<8>(0, 0); // 8k of CHR (ram)
+    	set_mirroring((regs[0] & 0b00010000) ? PPU::ONE_SCREEN_HI : PPU::ONE_SCREEN_LO); // Mirroring based on bit 5
+	}
+public:
+    Mapper7(u8* rom) : Mapper(rom) { regs[0] = 0; apply(); }
+	u8 write(u16 addr, u8 v) {
+    	if (addr & 0x8000) { regs[0] = v; apply(); } // Bank switching
+    	return v;
+	}
+	u8 chr_write(u16 addr, u8 v) { return chr[addr] = v; }
+};
 
 // Actual code
 namespace APU {
@@ -477,6 +495,8 @@ namespace PPU {
 		switch (mirroring) {
 			case VERTICAL:   return addr % 0x800;
 			case HORIZONTAL: return ((addr / 2) & 0x400) + (addr % 0x400);
+			case ONE_SCREEN_LO:
+        	case ONE_SCREEN_HI: return ((addr & 0x3ff) + ((mirroring == ONE_SCREEN_HI) ? 0x400 : 0x0)) - 0x2000;
 			default:         return addr - 0x2000;
 		}
 	}
@@ -715,6 +735,7 @@ namespace Cartridge {
 			case 2:  mapper = new Mapper2(rom); break;
 			case 3:  mapper = new Mapper3(rom); break;
 			case 4:  mapper = new Mapper4(rom); break;
+			case 7:  mapper = new Mapper7(rom); break;
 		}
 		CPU::power(), PPU::reset();
 	}