Create reset functionality in the debugger to restart the emulator

Jonazan2 · Oct 6, 2019 · c8f86c7 · c8f86c7
1 parent 5a8c1d0
commit c8f86c7
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Showing 8 changed files with 128 additions and 24 deletions.
diff --git a/Debugger/CpuDebugger.cpp b/Debugger/CpuDebugger.cpp
@@ -13,7 +13,7 @@ CpuDebugger::CpuDebugger()
 
 void CpuDebugger::ComposeView( Cpu &cpu, Memory &memory, u32 cycles, DebuggerMode& mode )
 {
-    ImGui::SetNextWindowPos( ImVec2( 0, 0 ) );
+    ImGui::SetNextWindowPos( ImVec2( 0, 100 ) );
     ImGui::Begin( "Cpu" );
     {
         ImGui::Columns( 2 );

diff --git a/Debugger/Debugger.cpp b/Debugger/Debugger.cpp
@@ -18,8 +18,9 @@ Debugger::Debugger( Cpu *cpu, Memory *memory, Video *video )
     : cpu( cpu )
     , memory( memory )
     , video( video )
-    , mode( DebuggerMode::IDLE )
     , window( nullptr )
+    , mode( DebuggerMode::IDLE )
+    , reset( false )
 {
 }
 
@@ -89,6 +90,12 @@ DebuggerUpdateResult Debugger::Update( float deltaMilliseconds, u32 cycles )
                 return DebuggerUpdateResult::QUIT;
             }
 
+            if ( reset )
+            {
+                reset = false;
+                return DebuggerUpdateResult::RESET;
+            }
+
             if ( elapsed.count() < 16.6f ) 
             {
                 std::this_thread::sleep_for( std::chrono::duration< float, std::milli > ( 16.6F - elapsed.count() ) );
@@ -110,17 +117,38 @@ DebuggerUpdateResult Debugger::Update( float deltaMilliseconds, u32 cycles )
         }
     }
 
+    if ( reset )
+    {
+        reset = false;
+        return DebuggerUpdateResult::RESET;
+    }
+
     return DebuggerUpdateResult::CONTINUE;
 }
 
 void Debugger::ComposeView( u32 cycles )
 {
     glfwPollEvents();
     ImGuiGLFW::NewFrame();
+
+    ComposeEmulatorControlView();
     cpuDebugger.ComposeView( *cpu, *memory, cycles, mode );
     videoDebugger.ComposeView( cycles, *video );
 }
 
+void Debugger::ComposeEmulatorControlView()
+{
+    ImGui::SetNextWindowPos( ImVec2( 0, 0 ) );
+    ImGui::Begin( "PatNes Control" );
+
+    if ( ImGui::Button( "Reset" ) )
+    {
+        reset = true;
+    }
+
+    ImGui::End();
+}
+
 void Debugger::Render()
 {
     i32 width, height;

diff --git a/Debugger/Debugger.h b/Debugger/Debugger.h
@@ -48,8 +48,10 @@ class Debugger
 
     GLFWwindow      *window;
     DebuggerMode    mode;
+    bool            reset;
 
     void ComposeView( u32 cycles );
+    void ComposeEmulatorControlView();
     void Render();
     bool ShouldCloseWindow() const;
 };
diff --git a/Memory.cpp b/Memory.cpp
@@ -8,17 +8,23 @@
 
 
 Memory::Memory( const Cartridge &cartridge, Video &video )
-    : video( video )
+    : cartridge( cartridge )
+    , video( video )
 {
     map = new byte[ 64_KB ];
-    memset( map, 0x00, 64_KB );
 
-    MapCartridge( cartridge );
 }
 
 Memory::~Memory()
 {
-    delete map;
+    delete[] map;
+}
+
+void Memory::Reset()
+{
+    memset( map, 0x00, 64_KB );
+
+    MapCartridge( cartridge );
 }
 
 byte Memory::Read( word address ) const

diff --git a/Memory.h b/Memory.h
@@ -4,17 +4,33 @@
 
 
 /*
- * MEMORY MAP
- *
- * 0x0000 - 0x07FF ( 2KB internal RAM )
- * 0x0800 - 0x0FFF ( Mirrors of RAM )
- * 0x1000 - 0x17FF ( Mirrors of RAM )
- * 0x1800 - 0x1FFF ( Mirrors of RAM )
- * 0x2000 - 0x2007 ( NES PPU registers )
- * 0x2008 - 0x3FFF ( Mirrors of PPU registers, repeat every 8 bytes )
- * 0x4000 - 0x4017 ( NES APU & IO registers )
- * 0x4018 - 0x401F ( APU and UI Functionality that is usually disabled )
- * 0x4020 - 0xFFFF ( Cartridge and mapper registers )
+
+    +-------------------------------------------------------------------------------+
+    |                                                                               |
+    |  NES Memory map                                                               |
+    |                                                                               |
+    +---------------------+---------------------------------------------------------+
+    |                     |                                                         |
+    |   0x0000 - 0x07FF   |  ( 2KB internal RAM )                                   |
+    |                     |                                                         |
+    |   0x0800 - 0x0FFF   |  ( Mirrors of RAM )                                     |
+    |                     |                                                         |
+    |   0x1000 - 0x17FF   |  ( Mirrors of RAM )                                     |
+    |                     |                                                         |
+    |   0x1800 - 0x1FFF   |  ( Mirrors of RAM )                                     |
+    |                     |                                                         |
+    |   0x2000 - 0x2007   |  ( NES PPU registers )                                  |
+    |                     |                                                         |
+    |   0x2008 - 0x3FFF   |  ( Mirrors of PPU registers, repeat every 8 bytes )     |
+    |                     |                                                         |
+    |   0x4000 - 0x4017   |  ( NES APU & IO registers )                             |
+    |                     |                                                         |
+    |   0x4018 - 0x401F   |  ( APU and UI Functionality that is usually disabled )  |
+    |                     |                                                         |
+    |   0x4020 - 0xFFFF   |  ( Cartridge and mapper registers )                     |
+    |                     |                                                         |
+    +---------------------+---------------------------------------------------------+
+
  */
 
 
@@ -28,15 +44,23 @@ class Memory
     Memory( const Cartridge &cartridge, Video &video );
     ~Memory();
 
+    void Reset();
+
+    /* Memory management */
     byte Read( word address ) const;
     void Write( word address, byte data );
 
     const byte *const GetMemoryMap() const;
 
 private:
 
-    byte        *map;
-    Video       &video;
+    /* Associated NES systems */
+    const Cartridge     &cartridge;
+    Video               &video;
+
+    /* NES memory map */
+    byte                *map;
+
 
     void MapCartridge( const Cartridge &cartridge );
 };
diff --git a/Video.cpp b/Video.cpp
@@ -10,8 +10,23 @@ Video::Video( Cartridge *cartridge )
     : cartridge( cartridge )
 {
     memory = new byte[ 16_KB ];
+    frameBuffer = new RGB[ NES_VIDEO_RESOLUTION ];
+
+    Reset();
+}
+
+Video::~Video()
+{
+    delete[] memory;
+    delete[] frameBuffer;
+}
+
+
+void Video::Reset()
+{
     memset( memory, 0x00, 16_KB );
-    MapCartridgeCHRToPPU();    
+    memset( frameBuffer, 0x00, NES_VIDEO_RESOLUTION );
+    MapCartridgeCHRToPPU();
 }
 
 void Video::MapCartridgeCHRToPPU()
@@ -25,10 +40,14 @@ void Video::MapCartridgeCHRToPPU()
     const u32 dataSize = header.chrRomSizeKB * 1_KB;
     memcpy( memory, &cartridgeRom[ offset ], dataSize );
 
-
     memory[ PPUSTATUS_REGISTER ] = 0b1010'0000;
 }
 
+RGB* Video::GetFrameBuffer() const
+{
+    return frameBuffer;
+}
+
 const byte * const Video::GetPPUMemory() const
 {
     return memory;

diff --git a/Video.h b/Video.h
@@ -39,15 +39,21 @@ class Cartridge;
 class Video
 {
 public:
+
+    static constexpr u32 NES_VIDEO_RESOLUTION = 256 * 240;
+
     Video( Cartridge *memory );
+    ~Video();
+
+    void Reset();
 
     /* PPU memory management */
     const byte * const GetPPUMemory() const;
     byte Read( word address ) const;
     void Write( word address, byte data );
 
     /* Frame buffer */
-    byte* GetFrameBuffer() const;
+    RGB* GetFrameBuffer() const;
 
 private:
 
@@ -69,7 +75,7 @@ class Video
     byte            *memory;
 
     /* Frame buffer */
-    byte            *frameBuffer;
+    RGB             *frameBuffer;
 
 
     void MapCartridgeCHRToPPU();

diff --git a/main.cpp b/main.cpp
@@ -6,6 +6,8 @@
 #include "Video.h"
 #include "Debugger/Debugger.h"
 
+#include <assert.h>
+
 static constexpr u32 AVERAGE_CYCLES_PER_FRAME = 29780;
 
 int main(int argc, char** argv)
@@ -40,7 +42,24 @@ int main(int argc, char** argv)
     {
         currentCycles += cpu.Update();
         DebuggerUpdateResult result = debugger.Update( 0.f, currentCycles );
-        quit = ( result == DebuggerUpdateResult::QUIT );
+
+        switch ( result )
+        {
+            case DebuggerUpdateResult::QUIT:
+            {
+                quit = true;
+            }
+            break;
+
+            case DebuggerUpdateResult::RESET:
+            {
+                memory.Reset();
+                video.Reset();
+                cpu.Reset();
+                currentCycles = 0;
+            }
+            break;
+        }
     }
 
     return 0;