Implement APU [WIP]

.gitignore

@@ -1,6 +1,9 @@
 .vs/
+.vscode/
 build/
 *.DS_Store
 cmake-build-debug/
 .idea/
 src/.vscode/
+CMakeSettings.json
+run.sh

CMakeLists.txt

@@ -8,9 +8,12 @@ set(CMAKE_CXX_STANDARD_REQUIRED ON)
 set(CMAKE_CXX_EXTENSIONS OFF)
 set(CMAKE_VERBOSE_MAKEFILE ON CACHE BOOL "ON")
 
+find_package(SDL2 REQUIRED)
+
 if (DEBUG)
     set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -DDEBUG")
 endif()
 
 add_executable(${PROJECT_NAME} src/main.cpp)
+target_link_libraries(${PROJECT_NAME} SDL2::SDL2 SDL2::SDL2main)
 add_subdirectory(src)

src/CMakeLists.txt

@@ -5,6 +5,7 @@ set(SOURCES
         gameBoy.cpp
         mmap.cpp
         graphics.cpp
+        sound.cpp
 
         # -------
         # Header Files
@@ -13,6 +14,7 @@ set(SOURCES
         mmap.h
         types.h
         graphics.h
+        sound.h
         )
 
 target_sources(${PROJECT_NAME} PRIVATE ${SOURCES})

src/cpu.cpp

@@ -61,17 +61,17 @@ CPU::CPU()
 	// TODO: check the initial state of IME
 	IMEFlag = -1;
 
-	IMEReg = false;
-}
+		IMEReg = false;
+	}
 
-// NOP just adds 4 cycles
-// Does nothing
-int CPU::NOP()
-{
-	reg_PC.dat += 1;
-	debugPrint("NOP\n");
-	return 4;
-}
+	// NOP just adds 4 cycles
+	// Does nothing
+	int CPU::NOP()
+	{
+		reg_PC.dat += 1;
+		debugPrint("NOP\n");
+		return 4;
+	}
 
 // LD BC, u16
 // Loads a 16 bit immediate value into BC

src/gameBoy.cpp

@@ -2,6 +2,8 @@
 #include "cpu.h"
 #include "gameBoy.h"
 
+#include <chrono>
+
 int GBE::s_Cycles;
 
 GBE::GBE()
@@ -15,6 +17,10 @@ GBE::GBE()
 	// Initialize the Graphics
 	gbe_graphics = new PPU();
 
+	// Initialize the APU
+	gbe_sound = new APU();
+
+
 	// Unify the CPU and MemoryMap
 	gbe_cpu->setMemory(gbe_mMap);
 
@@ -24,14 +30,21 @@ GBE::GBE()
 	// Unify the PPU and MmeoryMap
 	gbe_graphics->setMemoryMap(gbe_mMap);
 
+	// Unify the CPU and MemoryMap
+	gbe_sound->setMemoryMap(gbe_mMap);
+
+	// SDL_INIT_AUDIO and SDL_INIT_VIDEO both are initilised in graphics.cpp
+	// Don't change ordering of gbe_graphics and gbe_sound
 	gbe_graphics->init();
 
+	gbe_sound->init();
+
 	// Open the Boot ROM
 	if ((bootROM = fopen("../src/dmg_boot.gb", "rb")) == NULL)
 		printf("boot rom file not opened");
 
 	// Open the Game ROM
-	if ((gameROM = fopen("../tests/pkmnred.gb", "rb")) == NULL)
+	if ((gameROM = fopen("../tests/dmg_sound/rom_singles/01-registers.gb", "rb")) == NULL)
 		printf("game rom file not opened");
 
 	// Set the Boot ROM
@@ -98,7 +111,6 @@ GBE::GBE()
 	gbe_mMap->debugWriteMemory(0x133, 0x3E);
 
 	executeBootROM();
-
 	update();
 }
 
@@ -111,14 +123,20 @@ void GBE::update()
 	{
 		// Execute the next instruction
 		s_Cycles += gbe_cpu->executeNextInstruction();
-
 		// update the DIV and TIMA timers
 		gbe_cpu->updateTimers(s_Cycles);
 		gbe_graphics->executePPU(s_Cycles);
+		// this runs at a freq of around 27 * freq(DIV) = 442368 Hz
+		// this is probably enough to implement APU
+		gbe_sound->stepAPU(s_Cycles);
+		gbe_sound->test(s_Cycles);
 		s_Cycles = 0;
 		s_Cycles += gbe_cpu->performInterrupt();
+		// printf("s_Cycles after: %d\n\n", s_Cycles);
 		gbe_graphics->pollEvents();
 	}
+
+	// printf("a: %lld\n", a);
 }
 
 void GBE::executeBootROM()

src/gameBoy.h

@@ -3,6 +3,7 @@
 #include "cpu.h"
 #include "mmap.h"
 #include "graphics.h"
+#include "sound.h"
 
 // GBE stands for GameBoyEmulator
 
@@ -28,6 +29,9 @@ class GBE
 	// Pointer to the Graphics
 	PPU* gbe_graphics;
 
+	// Pointer to the Sound
+	APU* gbe_sound;
+
 	// File pointer for Boot ROM
 	FILE* bootROM;
 

src/graphics.cpp

@@ -35,36 +35,41 @@ PPU::PPU()
 bool PPU::init()
 {
 	// Initialize SDL
-	if (SDL_Init(SDL_INIT_VIDEO) < 0)
+	if (SDL_Init(SDL_INIT_VIDEO | SDL_INIT_AUDIO) < 0)
 	{
 		printf("SDL could not initialize! SDL_Error: %s\n", SDL_GetError());
+		SDL_Quit();
 		return false;
 	}
 
 	// Set hint to use hardware acceleration
 	if (!SDL_SetHint(SDL_HINT_RENDER_SCALE_QUALITY, "1"))
 	{
 		printf("Hardware Acceleration not enabled! SDL_Error: %s\n", SDL_GetError());
+		SDL_Quit();
 		return false;
 	}
 
 	// Set hint for VSync
 	if (!SDL_SetHint(SDL_HINT_RENDER_VSYNC, "1"))
 	{
 		printf("VSync not enabled! SDL_Error: %s\n", SDL_GetError());
+		SDL_Quit();
 		return false;
 	}
 
 	// Create window and renderer
 	if (!(window = SDL_CreateWindow("GameBoy Emulator", SDL_WINDOWPOS_CENTERED, SDL_WINDOWPOS_CENTERED, SCREEN_WIDTH * 2, SCREEN_HEIGHT * 2, SDL_WINDOW_SHOWN)))
 	{
 		printf("Window could not be created! SDL_Error: %s\n", SDL_GetError());
+		SDL_Quit();
 		return false;
 	}
 
 	if (!(renderer = SDL_CreateRenderer(window, -1, SDL_RENDERER_ACCELERATED | SDL_RENDERER_PRESENTVSYNC)))
 	{
 		printf("Renderer could not be created! SDL_Error: %s\n", SDL_GetError());
+		SDL_Quit();
 		return false;
 	}