Merge pull request #330 from TomHarte/SCC

Adds emulation of the Konami SCC

Components/AY38910/AY38910.cpp

@@ -66,7 +66,7 @@ AY38910::AY38910(Concurrency::DeferringAsyncTaskQueue &task_queue) : task_queue_
 }
 
 void AY38910::get_samples(std::size_t number_of_samples, int16_t *target) {
-	unsigned int c = 0;
+	std::size_t c = 0;
 	while((master_divider_&7) && c < number_of_samples) {
 		target[c] = output_volume_;
 		master_divider_++;

Components/KonamiSCC/KonamiSCC.cpp

@@ -0,0 +1,107 @@
+//
+//  KonamiSCC.cpp
+//  Clock Signal
+//
+//  Created by Thomas Harte on 06/01/2018.
+//  Copyright © 2018 Thomas Harte. All rights reserved.
+//
+
+#include "KonamiSCC.hpp"
+
+#include <cstring>
+
+using namespace Konami;
+
+SCC::SCC(Concurrency::DeferringAsyncTaskQueue &task_queue) :
+	task_queue_(task_queue) {}
+
+bool SCC::is_silent() {
+	return !(channel_enable_ & 0x1f);
+}
+
+void SCC::get_samples(std::size_t number_of_samples, std::int16_t *target) {
+	if(is_silent()) {
+		std::memset(target, 0, sizeof(std::int16_t) * number_of_samples);
+		return;
+	}
+
+	std::size_t c = 0;
+	while((master_divider_&7) && c < number_of_samples) {
+		target[c] = output_volume_;
+		master_divider_++;
+		c++;
+	}
+
+	while(c < number_of_samples) {
+		for(int channel = 0; channel < 5; ++channel) {
+			if(channels_[channel].tone_counter) channels_[channel].tone_counter--;
+			else {
+				channels_[channel].offset = (channels_[channel].offset + 1) & 0x1f;
+				channels_[channel].tone_counter = channels_[channel].period;
+			}
+		}
+
+		evaluate_output_volume();
+
+		for(int ic = 0; ic < 8 && c < number_of_samples; ++ic) {
+			target[c] = output_volume_;
+			c++;
+			master_divider_++;
+		}
+	}
+}
+
+void SCC::write(uint16_t address, uint8_t value) {
+	address &= 0xff;
+	if(address < 0x80) ram_[address] = value;
+
+	task_queue_.defer([=] {
+		// Check for a write into waveform memory.
+		if(address < 0x80) {
+			waves_[address >> 5].samples[address & 0x1f] = value;
+		} else switch(address) {
+			default: break;
+
+			case 0x80: case 0x82: case 0x84: case 0x86: case 0x88: {
+				int channel = (address - 0x80) >> 1;
+				channels_[channel].period = (channels_[channel].period & ~0xff) | value;
+			} break;
+
+			case 0x81: case 0x83: case 0x85: case 0x87: case 0x89: {
+				int channel = (address - 0x80) >> 1;
+				channels_[channel].period = (channels_[channel].period & 0xff) | ((value & 0xf) << 8);
+			} break;
+
+			case 0x8a: case 0x8b: case 0x8c: case 0x8d: case 0x8e:
+				channels_[address - 0x8a].amplitude = value & 0xf;
+			break;
+
+			case 0x8f:
+				channel_enable_ = value;
+			break;
+		}
+
+		evaluate_output_volume();
+	});
+}
+
+void SCC::evaluate_output_volume() {
+	output_volume_ =
+		static_cast<int16_t>(
+			(
+				(channel_enable_ & 0x01) ? static_cast<int8_t>(waves_[0].samples[channels_[0].offset]) * channels_[0].amplitude : 0 +
+				(channel_enable_ & 0x02) ? static_cast<int8_t>(waves_[1].samples[channels_[1].offset]) * channels_[1].amplitude : 0 +
+				(channel_enable_ & 0x04) ? static_cast<int8_t>(waves_[2].samples[channels_[2].offset]) * channels_[2].amplitude : 0 +
+				(channel_enable_ & 0x08) ? static_cast<int8_t>(waves_[3].samples[channels_[3].offset]) * channels_[3].amplitude : 0 +
+				(channel_enable_ & 0x10) ? static_cast<int8_t>(waves_[3].samples[channels_[4].offset]) * channels_[4].amplitude : 0
+			)
+		);
+}
+
+uint8_t SCC::read(uint16_t address) {
+	address &= 0xff;
+	if(address < 0x80) {
+		return ram_[address];
+	}
+	return 0xff;
+}

Components/KonamiSCC/KonamiSCC.hpp

@@ -0,0 +1,72 @@
+//
+//  KonamiSCC.hpp
+//  Clock Signal
+//
+//  Created by Thomas Harte on 06/01/2018.
+//  Copyright © 2018 Thomas Harte. All rights reserved.
+//
+
+#ifndef KonamiSCC_hpp
+#define KonamiSCC_hpp
+
+#include "../../Outputs/Speaker/Implementation/SampleSource.hpp"
+#include "../../Concurrency/AsyncTaskQueue.hpp"
+
+namespace Konami {
+
+/*!
+	Provides an emulation of Konami's Sound Creative Chip ('SCC').
+
+	The SCC is a primitive wavetable synthesis chip, offering 32-sample tables,
+	and five channels of output. The original SCC uses the same wave for channels
+	four and five, the SCC+ supports different waves for the two channels.
+*/
+class SCC: public ::Outputs::Speaker::SampleSource {
+	public:
+		/// Creates a new SCC.
+		SCC(Concurrency::DeferringAsyncTaskQueue &task_queue);
+
+		/// As per ::SampleSource; provides a broadphase test for silence.
+		bool is_silent();
+
+		/// As per ::SampleSource; provides audio output.
+		void get_samples(std::size_t number_of_samples, std::int16_t *target);
+
+		/// Writes to the SCC.
+		void write(uint16_t address, uint8_t value);
+
+		/// Reads from the SCC.
+		uint8_t read(uint16_t address);
+
+	private:
+		Concurrency::DeferringAsyncTaskQueue &task_queue_;
+
+		// State from here on down is accessed ony from the audio thread.
+		int master_divider_ = 0;
+		int16_t output_volume_ = 0;
+
+		struct Channel {
+			int period = 0;
+			int amplitude = 0;
+
+			int tone_counter = 0;
+			int offset = 0;
+		} channels_[5];
+
+		struct Wavetable {
+			std::uint8_t samples[32];
+		} waves_[4];
+
+		std::uint8_t channel_enable_ = 0;
+		std::uint8_t test_register_ = 0;
+
+		void evaluate_output_volume();
+
+		// This keeps a copy of wave memory that is accessed from the
+		// main emulation thread.
+		std::uint8_t ram_[128];
+};
+
+}
+
+#endif /* KonamiSCC_hpp */

Machines/MSX/Cartridges/KonamiWithSCC.hpp

@@ -10,16 +10,17 @@
 #define KonamiWithSCC_hpp
 
 #include "../ROMSlotHandler.hpp"
+#include "../../../Components/KonamiSCC/KonamiSCC.hpp"
 
 namespace MSX {
 namespace Cartridge {
 
 class KonamiWithSCCROMSlotHandler: public ROMSlotHandler {
 	public:
-		KonamiWithSCCROMSlotHandler(MSX::MemoryMap &map, int slot) :
+		KonamiWithSCCROMSlotHandler(MSX::MemoryMap &map, int slot, Konami::SCC &scc) :
-			map_(map), slot_(slot) {}
+			map_(map), slot_(slot), scc_(scc) {}
 
-		void write(uint16_t address, uint8_t value) {
+		void write(uint16_t address, uint8_t value) override {
 			switch(address >> 11) {
 				default: break;
 				case 0x0a:
@@ -29,7 +30,16 @@ class KonamiWithSCCROMSlotHandler: public ROMSlotHandler {
 					map_.map(slot_, value * 8192, 0x6000, 0x2000);
 				break;
 				case 0x12:
-					map_.map(slot_, value * 8192, 0x8000, 0x2000);
+					if((value&0x3f) == 0x3f) {
+						scc_is_visible_ = true;
+						map_.unmap(slot_, 0x8000, 0x2000);
+					} else {
+						scc_is_visible_ = false;
+						map_.map(slot_, value * 8192, 0x8000, 0x2000);
+					}
+				break;
+				case 0x13:
+					if(scc_is_visible_) scc_.write(address, value);
 				break;
 				case 0x16:
 					map_.map(slot_, value * 8192, 0xa000, 0x2000);
@@ -37,9 +47,18 @@ class KonamiWithSCCROMSlotHandler: public ROMSlotHandler {
 			}
 		}
 
+		uint8_t read(uint16_t address) override {
+			if(scc_is_visible_ && address >= 0x9800 && address < 0xa000) {
+				return scc_.read(address);
+			}
+			return 0xff;
+		}
+
 	private:
 		MSX::MemoryMap &map_;
 		int slot_;
+		Konami::SCC &scc_;
+		bool scc_is_visible_ = false;
 };
 
 }

Machines/MSX/MSX.cpp

@@ -22,6 +22,7 @@
 #include "../../Components/9918/9918.hpp"
 #include "../../Components/8255/i8255.hpp"
 #include "../../Components/AY38910/AY38910.hpp"
+#include "../../Components/KonamiSCC/KonamiSCC.hpp"
 
 #include "../../Storage/Tape/Parsers/MSX.hpp"
 #include "../../Storage/Tape/Tape.hpp"
@@ -120,7 +121,8 @@ class ConcreteMachine:
 			i8255_(i8255_port_handler_),
 			ay_(audio_queue_),
 			audio_toggle_(audio_queue_),
-			mixer_(ay_, audio_toggle_),
+			scc_(audio_queue_),
+			mixer_(ay_, audio_toggle_, scc_),
 			speaker_(mixer_),
 			tape_player_(3579545 * 2),
 			i8255_port_handler_(*this, audio_toggle_, tape_player_),
@@ -167,7 +169,7 @@ class ConcreteMachine:
 				break;
 				case StaticAnalyser::MSXCartridgeType::KonamiWithSCC:
 					// TODO: enable an SCC.
-					memory_slots_[1].set_handler(new Cartridge::KonamiWithSCCROMSlotHandler(*this, 1));
+					memory_slots_[1].set_handler(new Cartridge::KonamiWithSCCROMSlotHandler(*this, 1, scc_));
 				break;
 				case StaticAnalyser::MSXCartridgeType::ASCII8kb:
 					memory_slots_[1].set_handler(new Cartridge::ASCII8kbROMSlotHandler(*this, 1));
@@ -317,6 +319,7 @@ class ConcreteMachine:
 
 					int slot_hit = (paged_memory_ >> ((address >> 14) * 2)) & 3;
 					if(memory_slots_[slot_hit].handler) {
+						update_audio();
 						memory_slots_[slot_hit].handler->run_for(memory_slots_[slot_hit].cycles_since_update.flush());
 						memory_slots_[slot_hit].handler->write(address, *cycle.value);
 					}
@@ -568,8 +571,9 @@ class ConcreteMachine:
 		Concurrency::DeferringAsyncTaskQueue audio_queue_;
 		GI::AY38910::AY38910 ay_;
 		AudioToggle audio_toggle_;
-		Outputs::Speaker::CompoundSource<GI::AY38910::AY38910, AudioToggle> mixer_;
+		Konami::SCC scc_;
-		Outputs::Speaker::LowpassSpeaker<Outputs::Speaker::CompoundSource<GI::AY38910::AY38910, AudioToggle>> speaker_;
+		Outputs::Speaker::CompoundSource<GI::AY38910::AY38910, AudioToggle, Konami::SCC> mixer_;
+		Outputs::Speaker::LowpassSpeaker<Outputs::Speaker::CompoundSource<GI::AY38910::AY38910, AudioToggle, Konami::SCC>> speaker_;
 
 		Storage::Tape::BinaryTapePlayer tape_player_;
 		bool use_fast_tape_ = false;

OSBindings/Mac/Clock Signal.xcodeproj/project.pbxproj

@@ -205,6 +205,8 @@
 		4B4518A41F75FD1C00926311 /* OricMFMDSK.cpp in Sources */ = {isa = PBXBuildFile; fileRef = 4B4518971F75FD1B00926311 /* OricMFMDSK.cpp */; };
 		4B4518A51F75FD1C00926311 /* SSD.cpp in Sources */ = {isa = PBXBuildFile; fileRef = 4B4518991F75FD1B00926311 /* SSD.cpp */; };
 		4B4A76301DB1A3FA007AAE2E /* AY38910.cpp in Sources */ = {isa = PBXBuildFile; fileRef = 4B4A762E1DB1A3FA007AAE2E /* AY38910.cpp */; };
+		4B4B1A3C200198CA00A0F866 /* KonamiSCC.cpp in Sources */ = {isa = PBXBuildFile; fileRef = 4B4B1A3A200198C900A0F866 /* KonamiSCC.cpp */; };
+		4B4B1A3D200198CA00A0F866 /* KonamiSCC.cpp in Sources */ = {isa = PBXBuildFile; fileRef = 4B4B1A3A200198C900A0F866 /* KonamiSCC.cpp */; };
 		4B4DC8211D2C2425003C5BF8 /* Vic20.cpp in Sources */ = {isa = PBXBuildFile; fileRef = 4B4DC81F1D2C2425003C5BF8 /* Vic20.cpp */; };
 		4B4DC82B1D2C27A4003C5BF8 /* SerialBus.cpp in Sources */ = {isa = PBXBuildFile; fileRef = 4B4DC8291D2C27A4003C5BF8 /* SerialBus.cpp */; };
 		4B5073071DDD3B9400C48FBD /* ArrayBuilder.cpp in Sources */ = {isa = PBXBuildFile; fileRef = 4B5073051DDD3B9400C48FBD /* ArrayBuilder.cpp */; };
@@ -797,6 +799,8 @@
 		4B4518A81F76022000926311 /* DiskImageImplementation.hpp */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.cpp.h; path = DiskImageImplementation.hpp; sourceTree = "<group>"; };
 		4B4A762E1DB1A3FA007AAE2E /* AY38910.cpp */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.cpp.cpp; name = AY38910.cpp; path = AY38910/AY38910.cpp; sourceTree = "<group>"; };
 		4B4A762F1DB1A3FA007AAE2E /* AY38910.hpp */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.cpp.h; name = AY38910.hpp; path = AY38910/AY38910.hpp; sourceTree = "<group>"; };
+		4B4B1A3A200198C900A0F866 /* KonamiSCC.cpp */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.cpp.cpp; path = KonamiSCC.cpp; sourceTree = "<group>"; };
+		4B4B1A3B200198C900A0F866 /* KonamiSCC.hpp */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.cpp.h; path = KonamiSCC.hpp; sourceTree = "<group>"; };
 		4B4DC81F1D2C2425003C5BF8 /* Vic20.cpp */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.cpp.cpp; path = Vic20.cpp; sourceTree = "<group>"; };
 		4B4DC8201D2C2425003C5BF8 /* Vic20.hpp */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.cpp.h; path = Vic20.hpp; sourceTree = "<group>"; };
 		4B4DC8271D2C2470003C5BF8 /* C1540.hpp */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.cpp.h; path = C1540.hpp; sourceTree = "<group>"; };
@@ -1801,6 +1805,15 @@
 			name = AY38910;
 			sourceTree = "<group>";
 		};
+		4B4B1A39200198C900A0F866 /* KonamiSCC */ = {
+			isa = PBXGroup;
+			children = (
+				4B4B1A3A200198C900A0F866 /* KonamiSCC.cpp */,
+				4B4B1A3B200198C900A0F866 /* KonamiSCC.hpp */,
+			);
+			path = KonamiSCC;
+			sourceTree = "<group>";
+		};
 		4B4DC81D1D2C2425003C5BF8 /* Commodore */ = {
 			isa = PBXGroup;
 			children = (
@@ -2607,11 +2620,12 @@
 				4BC9DF4B1D04691600F44158 /* 6522 */,
 				4B1E85791D174DEC001EF87D /* 6532 */,
 				4BC9DF4C1D04691600F44158 /* 6560 */,
-				4B4A762D1DB1A35C007AAE2E /* AY38910 */,
 				4BE845221F2FF7F400A5EA22 /* 6845 */,
 				4BD9137C1F3115AC009BCF85 /* 8255 */,
 				4BBC951F1F368D87008F4C34 /* 8272 */,
 				4B0E04F71FC9F2C800F43484 /* 9918 */,
+				4B4A762D1DB1A35C007AAE2E /* AY38910 */,
+				4B4B1A39200198C900A0F866 /* KonamiSCC */,
 			);
 			name = Components;
 			path = ../../Components;
@@ -3319,6 +3333,7 @@
 				4B055AA31FAE85DF0060FFFF /* ImplicitSectors.cpp in Sources */,
 				4B055AAE1FAE85FD0060FFFF /* TrackSerialiser.cpp in Sources */,
 				4B055A981FAE85C50060FFFF /* Drive.cpp in Sources */,
+				4B4B1A3D200198CA00A0F866 /* KonamiSCC.cpp in Sources */,
 				4B055AE21FAE9B6F0060FFFF /* CRTOpenGL.cpp in Sources */,
 				4B055AC31FAE9AE80060FFFF /* AmstradCPC.cpp in Sources */,
 				4B055A9E1FAE85DA0060FFFF /* G64.cpp in Sources */,
@@ -3445,6 +3460,7 @@
 				4B8FE2221DA19FB20090D3CE /* MachinePanel.swift in Sources */,
 				4B4518A41F75FD1C00926311 /* OricMFMDSK.cpp in Sources */,
 				4BBB14311CD2CECE00BDB55C /* IntermediateShader.cpp in Sources */,
+				4B4B1A3C200198CA00A0F866 /* KonamiSCC.cpp in Sources */,
 				4BD5F1951D13528900631CD1 /* CSBestEffortUpdater.mm in Sources */,
 				4B96F7221D75119A0058BB2D /* Tape.cpp in Sources */,
 				4B4518811F75E91A00926311 /* PCMPatchedTrack.cpp in Sources */,

OSBindings/Mac/Clock Signal.xcodeproj/xcshareddata/xcschemes/Clock Signal.xcscheme

@@ -72,6 +72,7 @@
       buildConfiguration = "Debug"
       selectedDebuggerIdentifier = "Xcode.DebuggerFoundation.Debugger.LLDB"
       selectedLauncherIdentifier = "Xcode.DebuggerFoundation.Launcher.LLDB"
+      enableASanStackUseAfterReturn = "YES"
       disableMainThreadChecker = "YES"
       language = ""
       launchStyle = "0"

OSBindings/SDL/SConstruct

@@ -17,6 +17,7 @@ SOURCES += glob.glob('../../Components/8272/*.cpp')
 SOURCES += glob.glob('../../Components/9918/*.cpp')
 SOURCES += glob.glob('../../Components/9918/Implementation/*.cpp')
 SOURCES += glob.glob('../../Components/AY38910/*.cpp')
+SOURCES += glob.glob('../../Components/KonamiSCC/*.cpp')
 
 SOURCES += glob.glob('../../Concurrency/*.cpp')
 

Outputs/Speaker/Implementation/CompoundSource.hpp

@@ -31,19 +31,22 @@ template <typename... T> class CompoundSource: public Outputs::Speaker::SampleSo
 	A CompoundSource adds together the sound generated by multiple individual SampleSources.
 	It's an instance of template metaprogramming; this is the recursive case.
 */
-template <typename T, typename... R> class CompoundSource<T, R...>: public Outputs::Speaker::SampleSource {
+template <typename T, typename... R> class CompoundSource<T, R...>:
+	public Outputs::Speaker::SampleSource {
 	public:
 		CompoundSource(T &source, R &...next) : source_(source), next_source_(next...) {}
 
 		void get_samples(std::size_t number_of_samples, std::int16_t *target) {
-			// This is an ugly solution: get whatever the next source supplies and add the local
+			if(source_.is_silent()) {
-			// results to it, with the degenerate case performing a memset to supply an array of 0.
+				source_.skip_samples(number_of_samples);
-			// TODO: do better. Might need some alteration of SampleSource.
+				next_source_.get_samples(number_of_samples, target);
-			int16_t next_samples[number_of_samples];
+			} else {
-			next_source_.get_samples(number_of_samples, next_samples);
+				int16_t next_samples[number_of_samples];
-			source_.get_samples(number_of_samples, target);
+				next_source_.get_samples(number_of_samples, next_samples);
-			while(number_of_samples--) {
+				source_.get_samples(number_of_samples, target);
-				target[number_of_samples] += next_samples[number_of_samples];
+				while(number_of_samples--) {
+					target[number_of_samples] += next_samples[number_of_samples];
+				}
 			}
 		}
 
@@ -53,6 +56,7 @@ template <typename T, typename... R> class CompoundSource<T, R...>: public Outpu
 		}
 
 	private:
+		bool is_sleeping_ = false;
 		T &source_;
 		CompoundSource<R...> next_source_;
 };

Outputs/Speaker/Implementation/SampleSource.hpp

@@ -37,6 +37,15 @@ class SampleSource {
 			std::int16_t scratch_pad[number_of_samples];
 			get_samples(number_of_samples, scratch_pad);
 		}
+
+		/*!
+			@returns @c true if it is trivially true that a call to get_samples would just
+				fill the target with zeroes; @c false if a call might return all zeroes or
+				might not.
+		*/
+		bool is_silent() {
+			return false;
+		}
 };
 
 }