Initial commit

.gitignore

@@ -1,3 +1,5 @@
 .sconsign.dblite
 laines
 *.o
+roms
+.nes

src/apu.cpp

@@ -5,46 +5,46 @@
 namespace APU {
 
 
-Nes_Apu apu;
+//Nes_Apu apu;
-Blip_Buffer buf;
+//Blip_Buffer buf;
 
 const int OUT_SIZE = 4096;
-blip_sample_t outBuf[OUT_SIZE];
+//blip_sample_t outBuf[OUT_SIZE];
 
-void init()
+/*void init()
 {
     buf.sample_rate(96000);
     buf.clock_rate(1789773);
 
     apu.output(&buf);
     apu.dmc_reader(CPU::dmc_read);
-}
+}*/
 
-void reset()
+/*void reset()
 {
     apu.reset();
     buf.clear();
-}
+}*/
 
 template <bool write> u8 access(int elapsed, u16 addr, u8 v)
 {
-    if (write)
+    /*if (write)
         apu.write_register(elapsed, addr, v);
     else if (addr == apu.status_addr)
-        v = apu.read_status(elapsed);
+        v = apu.read_status(elapsed);*/
 
     return v;
 }
 template u8 access<0>(int, u16, u8); template u8 access<1>(int, u16, u8);
 
-void run_frame(int elapsed)
+/*void run_frame(int elapsed)
 {
     apu.end_frame(elapsed);
     buf.end_frame(elapsed);
 
     if (buf.samples_avail() >= OUT_SIZE)
         GUI::new_samples(outBuf, buf.read_samples(outBuf, OUT_SIZE));
-}
+}*/
 
 
 }

src/cartridge.cpp

@@ -6,6 +6,7 @@
 #include "mappers/mapper2.hpp"
 #include "mappers/mapper3.hpp"
 #include "mappers/mapper4.hpp"
+#include "mappers/mapper7.hpp"
 #include "ppu.hpp"
 #include "cartridge.hpp"
 
@@ -57,11 +58,12 @@ void load(const char* fileName)
         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();
-    APU::reset();
+    //APU::reset();
 }
 
 bool loaded()

src/cpu.cpp

@@ -275,7 +275,7 @@ void run_frame()
         exec();
     }
 
-    APU::run_frame(elapsed());
+    //APU::run_frame(elapsed());
 }
 
 

src/gui.cpp

@@ -1,7 +1,6 @@
 #include <csignal>
 #include <SDL2/SDL_image.h>
 #include <SDL2/SDL_ttf.h>
-#include "Sound_Queue.h"
 #include "apu.hpp"
 #include "cartridge.hpp"
 #include "cpu.hpp"
@@ -18,7 +17,7 @@ SDL_Texture* gameTexture;
 SDL_Texture* background;
 TTF_Font* font;
 u8 const* keys;
-Sound_Queue* soundQueue;
+//Sound_Queue* soundQueue;
 SDL_Joystick* joystick[] = { nullptr, nullptr };
 
 // Menus:
@@ -51,9 +50,9 @@ void init()
     for (int i = 0; i < SDL_NumJoysticks(); i++)
         joystick[i] = SDL_JoystickOpen(i);
 
-    APU::init();
+    //APU::init();
-    soundQueue = new Sound_Queue;
+    //soundQueue = new Sound_Queue;
-    soundQueue->init(96000);
+    //soundQueue->init(96000);
 
     // Initialize graphics structures:
     window      = SDL_CreateWindow  ("LaiNES",
@@ -203,10 +202,10 @@ void new_frame(u32* pixels)
     SDL_UpdateTexture(gameTexture, NULL, pixels, WIDTH * sizeof(u32));
 }
 
-void new_samples(const blip_sample_t* samples, size_t count)
+/*void new_samples(const blip_sample_t* samples, size_t count)
 {
     soundQueue->write(samples, count);
-}
+}*/
 
 /* Render the screen */
 void render()

src/include/apu.hpp

@@ -5,9 +5,9 @@ namespace APU {
 
 
 template <bool write> u8 access(int elapsed, u16 addr, u8 v = 0);
-void run_frame(int elapsed);
+//void run_frame(int elapsed);
-void reset();
+//void reset();
-void init();
+//void init();
 
 
 }

src/include/gui.hpp

@@ -1,7 +1,6 @@
 #pragma once
 #include <SDL2/SDL.h>
 #include <string>
-#include <Nes_Apu.h>
 #include "common.hpp"
 
 namespace GUI {
@@ -24,7 +23,7 @@ void render_texture(SDL_Texture* texture, int x, int y);
 
 u8 get_joypad_state(int n);
 void new_frame(u32* pixels);
-void new_samples(const blip_sample_t* samples, size_t count);
+//void new_samples(const blip_sample_t* samples, size_t count);
 void set_size(int mul);
 
 }

src/include/mappers/mapper7.hpp

@@ -0,0 +1,19 @@
+#pragma once
+#include "mapper.hpp"
+#include "ppu.hpp"
+
+class Mapper7 : public Mapper
+{
+    u8 regs[1];
+    void apply();
+
+  public:
+    Mapper7(u8* rom) : Mapper(rom)
+    {
+        regs[0] = 0;
+        apply();
+    }
+
+    u8 write(u16 addr, u8 v);
+    u8 chr_write(u16 addr, u8 v);
+};

src/include/ppu.hpp

@@ -5,8 +5,7 @@ namespace PPU {
 
 
 enum Scanline  { VISIBLE, POST, NMI, PRE };
-enum Mirroring { VERTICAL, HORIZONTAL };
+enum Mirroring { VERTICAL, HORIZONTAL, ONE_SCREEN_HI, ONE_SCREEN_LO, FOUR_SCREEN };
-
 /* Sprite buffer */
 struct Sprite
 {

src/mappers/mapper1.cpp

@@ -38,8 +38,10 @@ void Mapper1::apply()
     // Set mirroring:
     switch (regs[0] & 0b11)
     {
-        case 2:  set_mirroring(PPU::VERTICAL);   break;
+        case 0:  set_mirroring(PPU::ONE_SCREEN_LO); break;
-        case 3:  set_mirroring(PPU::HORIZONTAL); break;
+        case 1:  set_mirroring(PPU::ONE_SCREEN_HI); break;
+        case 2:  set_mirroring(PPU::VERTICAL);      break;
+        case 3:  set_mirroring(PPU::HORIZONTAL);    break;
     }
 }
 

src/mappers/mapper7.cpp

@@ -0,0 +1,39 @@
+#include "ppu.hpp"
+#include "mappers/mapper7.hpp"
+
+/* Based off of https://wiki.nesdev.com/w/index.php/AxROM */
+
+/* Apply the registers state */
+void Mapper7::apply()
+{
+   /*
+    * 32 kb PRG ROM Banks
+    * 0x8000 - 0xFFFF swappable
+    */
+    map_prg<32>(0, regs[0] & 0b00001111);
+
+    /* 8k of CHR (ram) */
+    map_chr<8>(0, 0);
+
+    /* Mirroring based on bit 5 */
+    set_mirroring((regs[0] & 0b00010000) ? PPU::ONE_SCREEN_HI : PPU::ONE_SCREEN_LO);
+}
+
+u8 Mapper7::write(u16 addr, u8 v)
+{
+    /* check for bus contingency? (addr & 0x8000 == v?)
+     * Seems not neccesary */
+
+    /* bank switching */
+    if (addr & 0x8000)
+    {
+        regs[0] = v;
+        apply();
+    }
+    return v;
+}
+
+u8 Mapper7::chr_write(u16 addr, u8 v)
+{
+    return chr[addr] = v;
+}

src/ppu.cpp

@@ -42,6 +42,9 @@ u16 nt_mirror(u16 addr)
     {
         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;
     }
 }