シリアル通信・割り込みを一部実装

Author: voidproc

dmge/Main.cpp

@@ -8,6 +8,7 @@
 #include "Audio/APU.h"
 #include "Timer.h"
 #include "Joypad.h"
+#include "Serial.h"
 #include "Interrupt.h"
 #include "Address.h"
 #include "Timing.h"
@@ -95,7 +96,7 @@ class DmgeApp
 
 		showDebugMonitor_ = config_.showDebugMonitor;
 
-		mem_.init(&ppu_, &apu_, &timer_, &joypad_, &lcd_, &interrupt_);
+		mem_.init(&ppu_, &apu_, &timer_, &joypad_, &lcd_, &interrupt_, &serial_);
 
 		joypad_.setButtonAssign(config_.gamepadButtonAssign);
 
@@ -508,6 +509,13 @@ class DmgeApp
 			timer_.update();
 		}
 
+		// Serial
+
+		for (int i : step(cycles))
+		{
+			serial_.update();
+		}
+
 		// PPU
 
 		for (int i : step(cycles / doubleSpeedFactor))
@@ -587,6 +595,8 @@ class DmgeApp
 
 	dmge::Joypad joypad_{ &mem_ };
 
+	dmge::Serial serial_{ interrupt_ };
+
 	dmge::DebugMonitor debugMonitor_{ &mem_, &cpu_, &apu_, &interrupt_ };
 
 	// モード（通常 or トレース）

dmge/Memory.cpp

@@ -5,6 +5,7 @@
 #include "Audio/APU.h"
 #include "Timer.h"
 #include "Joypad.h"
+#include "Serial.h"
 #include "Interrupt.h"
 #include "DebugPrint.h"
 
@@ -18,12 +19,13 @@ namespace dmge
 	{
 	}
 
-	void Memory::init(PPU* ppu, APU* apu, dmge::Timer* timer, dmge::Joypad* joypad, LCD* lcd, Interrupt* interrupt)
+	void Memory::init(PPU* ppu, APU* apu, dmge::Timer* timer, dmge::Joypad* joypad, LCD* lcd, Interrupt* interrupt, Serial* serial)
 	{
 		ppu_ = ppu;
 		apu_ = apu;
 		timer_ = timer;
 		joypad_ = joypad;
+		serial_ = serial;
 		lcd_ = lcd;
 		interrupt_ = interrupt;
 	}
@@ -185,9 +187,8 @@ namespace dmge
 		{
 			// Serial
 			// 0xff01 - 0xff02
-			// ...
 
-			goto Fallback_WriteToMemory;
+			serial_->writeRegister(addr, value);
 		}
 		else if (addr <= 0xff03)
 		{
@@ -507,7 +508,8 @@ namespace dmge
 		{
 			// Serial
 			// 0xff01 - 0xff02
-			// ...
+
+			return serial_->readRegister(addr);
 		}
 		else if (addr <= 0xff03)
 		{

dmge/Memory.h

@@ -11,6 +11,7 @@ namespace dmge
 	class APU;
 	class Timer;
 	class Joypad;
+	class Serial;
 	class LCD;
 	class Interrupt;
 
@@ -21,7 +22,7 @@ namespace dmge
 
 		~Memory();
 
-		void init(PPU* ppu, APU* apu, dmge::Timer* timer, dmge::Joypad* joypad, LCD* lcd, Interrupt* interrupt);
+		void init(PPU* ppu, APU* apu, dmge::Timer* timer, dmge::Joypad* joypad, LCD* lcd, Interrupt* interrupt, Serial* serial);
 
 		void reset();
 
@@ -78,6 +79,7 @@ namespace dmge
 		APU* apu_ = nullptr;
 		Timer* timer_ = nullptr;
 		Joypad* joypad_ = nullptr;
+		Serial* serial_ = nullptr;
 		LCD* lcd_ = nullptr;
 		Interrupt* interrupt_ = nullptr;
 

dmge/Serial.cpp

@@ -0,0 +1,86 @@
+#include "stdafx.h"
+#include "Serial.h"
+#include "Address.h"
+#include "Interrupt.h"
+#include "BitMask/InterruptFlag.h"
+
+namespace dmge
+{
+	namespace
+	{
+		int SerialClockCycles(SerialClockSpeed speed)
+		{
+			return speed == SerialClockSpeed::Normal ? 512 : 16;
+		}
+	}
+
+	Serial::Serial(Interrupt& interrupt)
+		: interrupt_{ interrupt }
+	{
+	}
+
+	void Serial::writeRegister(uint16 addr, uint8 value)
+	{
+		switch (addr)
+		{
+		case Address::SB:
+			transferData_ = value;
+			break;
+
+		case Address::SC:
+			if (value >> 7)
+			{
+				remainBits_ = (uint8)8;
+				clockSpeed_ = static_cast<SerialClockSpeed>((value >> 1) & 1);
+				clockSource_ = static_cast<SerialClockSource>(value & 1);
+
+				clock_ = SerialClockCycles(clockSpeed_);
+			}
+			break;
+		}
+	}
+
+	uint8 Serial::readRegister(uint16 addr) const
+	{
+		switch (addr)
+		{
+		case Address::SB:
+			return transferData_;
+
+		case Address::SC:
+			return ((uint8)transfering() << 7) | (((uint8)clockSpeed_) << 1) | ((uint8)clockSource_);
+		}
+
+		return 0;
+	}
+
+	bool Serial::transfering() const
+	{
+		return remainBits_.has_value();
+	}
+
+	void Serial::update()
+	{
+		if (not transfering()) return;
+
+		if (clock_ > 0)
+		{
+			if (--clock_ == 0)
+			{
+				transferData_ = (transferData_ << 1) | 1;
+				*remainBits_ -= 1;
+
+				if (*remainBits_ == 0)
+				{
+					// 転送が終わった
+					remainBits_.reset();
+					interrupt_.request(BitMask::InterruptFlagBit::Serial);
+				}
+				else
+				{
+					clock_ = SerialClockCycles(clockSpeed_);
+				}
+			}
+		}
+	}
+}

dmge/Serial.h

@@ -0,0 +1,46 @@
+#pragma once
+
+namespace dmge
+{
+	enum class SerialClockSource : uint8
+	{
+		External = 0,
+		Internal = 1
+	};
+
+	enum class SerialClockSpeed : uint8
+	{
+		Normal = 0,
+		Fast = 1
+	};
+
+	class Interrupt;
+
+	class Serial
+	{
+	public:
+		Serial(Interrupt& interrupt);
+
+		void writeRegister(uint16 addr, uint8 value);
+
+		uint8 readRegister(uint16 addr) const;
+
+		bool transfering() const;
+
+		void update();
+
+	private:
+		Interrupt& interrupt_;
+
+		// SB (0xFF01)
+		uint8 transferData_ = 0;
+
+		// SB (0xff02)
+
+		Optional<uint8> remainBits_{};
+		SerialClockSpeed clockSpeed_{};
+		SerialClockSource clockSource_{};
+		
+		uint8 clock_ = 0;
+	};
+}

dmge/dmge.vcxproj

@@ -144,6 +144,7 @@
     <ClCompile Include="Memory.cpp" />
     <ClCompile Include="PPU.cpp" />
     <ClCompile Include="RTC.cpp" />
+    <ClCompile Include="Serial.cpp" />
     <ClCompile Include="stdafx.cpp">
       <PrecompiledHeader Condition="'$(Configuration)|$(Platform)'=='Debug|x64'">Create</PrecompiledHeader>
       <PrecompiledHeader Condition="'$(Configuration)|$(Platform)'=='Release|x64'">Create</PrecompiledHeader>
@@ -280,6 +281,7 @@
     <ClInclude Include="PPUConstants.h" />
     <ClInclude Include="PPUMode.h" />
     <ClInclude Include="RTC.h" />
+    <ClInclude Include="Serial.h" />
     <ClInclude Include="stdafx.h" />
     <ClInclude Include="TileData.h" />
     <ClInclude Include="TileMapAttribute.h" />

dmge/dmge.vcxproj.filters

@@ -156,6 +156,9 @@
     <ClCompile Include="Audio\WaveChannel.cpp">
       <Filter>Source Files\Audio</Filter>
     </ClCompile>
+    <ClCompile Include="Serial.cpp">
+      <Filter>Source Files</Filter>
+    </ClCompile>
   </ItemGroup>
   <ItemGroup>
     <Image Include="App\icon.ico">
@@ -532,5 +535,8 @@
     <ClInclude Include="Version.h">
       <Filter>Header Files</Filter>
     </ClInclude>
+    <ClInclude Include="Serial.h">
+      <Filter>Header Files</Filter>
+    </ClInclude>
   </ItemGroup>
 </Project>