Implements enough wiring that the Master System will instantiate and talk to an OPLL.

Components/OPL2/OPL2.cpp

@@ -0,0 +1,113 @@
+//
+//  OPL2.cpp
+//  Clock Signal
+//
+//  Created by Thomas Harte on 02/04/2020.
+//  Copyright © 2020 Thomas Harte. all rights reserved.
+//
+
+#include "OPL2.hpp"
+
+namespace {
+
+/*
+
+	Credit for the fixed register lists goes to Nuke.YKT; I found them at:
+	https://siliconpr0n.org/archive/doku.php?id=vendor:yamaha:opl2#ym2413_instrument_rom
+
+	The arrays below begin with channel 1, each line is a single channel and the
+	format per channel is, from first byte to eighth:
+
+		Bytes 1 and 2:
+			Registers 1 and 2, i.e. modulator and carrier
+			amplitude modulation select, vibrato select, etc.
+
+		Byte 3:
+			b7, b6: modulator key scale level
+			b5...b0: modulator total level (inverted)
+
+		Byte 4:
+			b7: carrier key scale level
+			b3...b0: feedback level and waveform selects as per register 4
+
+		Bytes 5, 6:
+			Registers 4 and 5, i.e. decay and attack rate, modulator and carrier.
+
+		Bytes 7, 8:
+			Registers 6 and 6, i.e. decay-sustain level and release rate, modulator and carrier.
+
+*/
+
+constexpr uint8_t opll_patch_set[] = {
+	0x71, 0x61, 0x1e, 0x17, 0xd0, 0x78, 0x00, 0x17,
+	0x13, 0x41, 0x1a, 0x0d, 0xd8, 0xf7, 0x23, 0x13,
+	0x13, 0x01, 0x99, 0x00, 0xf2, 0xc4, 0x11, 0x23,
+	0x31, 0x61, 0x0e, 0x07, 0xa8, 0x64, 0x70, 0x27,
+	0x32, 0x21, 0x1e, 0x06, 0xe0, 0x76, 0x00, 0x28,
+	0x31, 0x22, 0x16, 0x05, 0xe0, 0x71, 0x00, 0x18,
+	0x21, 0x61, 0x1d, 0x07, 0x82, 0x81, 0x10, 0x07,
+	0x23, 0x21, 0x2d, 0x14, 0xa2, 0x72, 0x00, 0x07,
+	0x61, 0x61, 0x1b, 0x06, 0x64, 0x65, 0x10, 0x17,
+	0x41, 0x61, 0x0b, 0x18, 0x85, 0xf7, 0x71, 0x07,
+	0x13, 0x01, 0x83, 0x11, 0xfa, 0xe4, 0x10, 0x04,
+	0x17, 0xc1, 0x24, 0x07, 0xf8, 0xf8, 0x22, 0x12,
+	0x61, 0x50, 0x0c, 0x05, 0xc2, 0xf5, 0x20, 0x42,
+	0x01, 0x01, 0x55, 0x03, 0xc9, 0x95, 0x03, 0x02,
+	0x61, 0x41, 0x89, 0x03, 0xf1, 0xe4, 0x40, 0x13,
+};
+
+constexpr uint8_t vrc7_patch_set[] = {
+	0x03, 0x21, 0x05, 0x06, 0xe8, 0x81, 0x42, 0x27,
+	0x13, 0x41, 0x14, 0x0d, 0xd8, 0xf6, 0x23, 0x12,
+	0x11, 0x11, 0x08, 0x08, 0xfa, 0xb2, 0x20, 0x12,
+	0x31, 0x61, 0x0c, 0x07, 0xa8, 0x64, 0x61, 0x27,
+	0x32, 0x21, 0x1e, 0x06, 0xe1, 0x76, 0x01, 0x28,
+	0x02, 0x01, 0x06, 0x00, 0xa3, 0xe2, 0xf4, 0xf4,
+	0x21, 0x61, 0x1d, 0x07, 0x82, 0x81, 0x11, 0x07,
+	0x23, 0x21, 0x22, 0x17, 0xa2, 0x72, 0x01, 0x17,
+	0x35, 0x11, 0x25, 0x00, 0x40, 0x73, 0x72, 0x01,
+	0xb5, 0x01, 0x0f, 0x0f, 0xa8, 0xa5, 0x51, 0x02,
+	0x17, 0xc1, 0x24, 0x07, 0xf8, 0xf8, 0x22, 0x12,
+	0x71, 0x23, 0x11, 0x06, 0x65, 0x74, 0x18, 0x16,
+	0x01, 0x02, 0xd3, 0x05, 0xc9, 0x95, 0x03, 0x02,
+	0x61, 0x63, 0x0c, 0x00, 0x94, 0xc0, 0x33, 0xf6,
+	0x21, 0x72, 0x0d, 0x00, 0xc1, 0xd5, 0x56, 0x06,
+};
+
+constexpr uint8_t percussion_patch_set[] = {
+	0x01, 0x01, 0x18, 0x0f, 0xdf, 0xf8, 0x6a, 0x6d,
+	0x01, 0x01, 0x00, 0x00, 0xc8, 0xd8, 0xa7, 0x48,
+	0x05, 0x01, 0x00, 0x00, 0xf8, 0xaa, 0x59, 0x55,
+};
+
+}
+
+using namespace Yamaha;
+
+OPL2::OPL2(Personality personality, Concurrency::DeferringAsyncTaskQueue &task_queue): task_queue_(task_queue) {
+	(void)opll_patch_set;
+	(void)vrc7_patch_set;
+	(void)percussion_patch_set;
+}
+
+bool OPL2::is_zero_level() {
+	return true;
+}
+
+void OPL2::get_samples(std::size_t number_of_samples, std::int16_t *target) {
+	// TODO.
+}
+
+void OPL2::set_sample_volume_range(std::int16_t range) {
+	// TODO.
+}
+
+void OPL2::write(uint16_t address, uint8_t value) {
+	// TODO.
+	printf("OPL2 write: %02x to %d\n", value, address&1);
+}
+
+uint8_t OPL2::read(uint16_t address) {
+	// TODO.
+	return 0xff;
+}

Components/OPL2/OPL2.hpp

@@ -0,0 +1,51 @@
+//
+//  OPL2.hpp
+//  Clock Signal
+//
+//  Created by Thomas Harte on 02/04/2020.
+//  Copyright © 2020 Thomas Harte. All rights reserved.
+//
+
+#ifndef OPL2_hpp
+#define OPL2_hpp
+
+#include "../../Outputs/Speaker/Implementation/SampleSource.hpp"
+#include "../../Concurrency/AsyncTaskQueue.hpp"
+
+namespace Yamaha {
+
+/*!
+	Provides an emulation of the OPL2 core, along with its OPLL and VRC7 specialisations.
+*/
+class OPL2: public ::Outputs::Speaker::SampleSource {
+	public:
+		enum class Personality {
+			OPL2,	// Provides full configuration of all channels.
+			OPLL,	// Uses the OPLL sound font, permitting full configuration of only a single channel.
+			VRC7,	// Uses the VRC7 sound font, permitting full configuration of only a single channel.
+		};
+
+		// Creates a new OPL2, OPLL or VRC7.
+		OPL2(Personality personality, Concurrency::DeferringAsyncTaskQueue &task_queue);
+
+		/// As per ::SampleSource; provides a broadphase test for silence.
+		bool is_zero_level();
+
+		/// As per ::SampleSource; provides audio output.
+		void get_samples(std::size_t number_of_samples, std::int16_t *target);
+		void set_sample_volume_range(std::int16_t range);
+
+		/// Writes to the OPL.
+		void write(uint16_t address, uint8_t value);
+
+		/// Reads from the OPL.
+		uint8_t read(uint16_t address);
+
+	private:
+		Concurrency::DeferringAsyncTaskQueue &task_queue_;
+
+};
+
+}
+
+#endif /* OPL2_hpp */

Machines/MasterSystem/MasterSystem.cpp

@@ -12,6 +12,7 @@
 
 #include "../../Components/9918/9918.hpp"
 #include "../../Components/SN76489/SN76489.hpp"
+#include "../../Components/OPL2/OPL2.hpp"
 
 #include "../MachineTypes.hpp"
 #include "../../Configurable/Configurable.hpp"
@@ -20,6 +21,7 @@
 #include "../../ClockReceiver/JustInTime.hpp"
 
 #include "../../Outputs/Speaker/Implementation/LowpassSpeaker.hpp"
+#include "../../Outputs/Speaker/Implementation/CompoundSource.hpp"
 
 #define LOG_PREFIX "[SMS] "
 #include "../../Outputs/Log.hpp"
@@ -97,7 +99,9 @@ class ConcreteMachine:
 				(target.model == Target::Model::SG1000) ? TI::SN76489::Personality::SN76489 : TI::SN76489::Personality::SMS,
 				audio_queue_,
 				sn76489_divider),
-			speaker_(sn76489_),
+			opll_(Yamaha::OPL2::Personality::OPLL, audio_queue_),
+			mixer_(sn76489_, opll_),
+			speaker_(mixer_),
 			keyboard_({Inputs::Keyboard::Key::Enter, Inputs::Keyboard::Key::Escape}, {}) {
 			// Pick the clock rate based on the region.
 			const double clock_rate = target.region == Target::Region::Europe ? 3546893.0 : 3579540.0;
@@ -250,17 +254,29 @@ class ConcreteMachine:
 								time_until_interrupt_ = vdp_->get_time_until_interrupt();
 							break;
 							case 0xc0: {
-								Joystick *const joypad1 = static_cast<Joystick *>(joysticks_[0].get());
-								Joystick *const joypad2 = static_cast<Joystick *>(joysticks_[1].get());
-								*cycle.value = static_cast<uint8_t>(joypad1->get_state() | (joypad2->get_state() << 6));
+								if(memory_control_ & 0x4) {
+									if(has_fm_audio_ && (address & 0xff) == 0xf2) {
+										*cycle.value = opll_detection_word_;
+									} else {
+										*cycle.value = 0xff;
+									}
+								} else {
+									Joystick *const joypad1 = static_cast<Joystick *>(joysticks_[0].get());
+									Joystick *const joypad2 = static_cast<Joystick *>(joysticks_[1].get());
+									*cycle.value = static_cast<uint8_t>(joypad1->get_state() | (joypad2->get_state() << 6));
+								}
 							} break;
 							case 0xc1: {
-								Joystick *const joypad2 = static_cast<Joystick *>(joysticks_[1].get());
+								if(memory_control_ & 0x4) {
+									*cycle.value = 0xff;
+								} else {
+									Joystick *const joypad2 = static_cast<Joystick *>(joysticks_[1].get());
 
-								*cycle.value =
-									(joypad2->get_state() >> 2) |
-									0x30 |
-									get_th_values();
+									*cycle.value =
+										(joypad2->get_state() >> 2) |
+										0x30 |
+										get_th_values();
+								}
 							} break;
 
 							default:
@@ -271,14 +287,15 @@ class ConcreteMachine:
 
 					case CPU::Z80::PartialMachineCycle::Output:
 						switch(address & 0xc1) {
-							case 0x00:
+							case 0x00:		// i.e. even ports less than 0x40.
 								if(is_master_system(model_)) {
 									// TODO: Obey the RAM enable.
+									printf("Memory control: %02x\n", memory_control_);
 									memory_control_ = *cycle.value;
 									page_cartridge();
 								}
 							break;
-							case 0x01: {
+							case 0x01: {	// i.e. odd ports less than 0x40.
 								// A programmer can force the TH lines to 0 here,
 								// causing a phoney lightgun latch, so check for any
 								// discontinuity in TH inputs.
@@ -291,20 +308,26 @@ class ConcreteMachine:
 									vdp_->latch_horizontal_counter();
 								}
 							} break;
-							case 0x40: case 0x41:
+							case 0x40: case 0x41:	// i.e. ports 0x40–0x7f.
 								update_audio();
 								sn76489_.write(*cycle.value);
 							break;
-							case 0x80: case 0x81:
+							case 0x80: case 0x81:	// i.e. ports 0x80–0xbf.
 								vdp_->write(address, *cycle.value);
 								z80_.set_interrupt_line(vdp_->get_interrupt_line());
 								time_until_interrupt_ = vdp_->get_time_until_interrupt();
 							break;
-							case 0xc0:
-								LOG("TODO: [output] I/O port A/N; " << int(*cycle.value));
-							break;
-							case 0xc1:
-								LOG("TODO: [output] I/O port B/misc");
+							case 0xc1: case 0xc0:	// i.e. ports 0xc0–0xff.
+								if(has_fm_audio_) {
+									switch(address & 0xff) {
+										case 0xf0: case 0xf1:
+											opll_.write(address, *cycle.value);
+										break;
+										case 0xf2:
+											opll_detection_word_ = *cycle.value;
+										break;
+									}
+								}
 							break;
 
 							default:
@@ -313,6 +336,19 @@ class ConcreteMachine:
 						}
 					break;
 
+/*
+	TODO: implementation of the below is incomplete.
+	Re: io_port_control_
+
+	Set the TH pins for ports A and B as outputs. Set their output level
+	to any value desired by writing to bits 7 and 5. Read the state of both
+	TH pins back through bits 7 and 6 of port $DD. If the data returned is
+	the same as the data written, it's an export machine, otherwise it's
+	a domestic one.
+
+	— Charles MacDonald
+ */
+
 					case CPU::Z80::PartialMachineCycle::Interrupt:
 						*cycle.value = 0xff;
 					break;
@@ -417,7 +453,10 @@ class ConcreteMachine:
 
 		Concurrency::DeferringAsyncTaskQueue audio_queue_;
 		TI::SN76489 sn76489_;
-		Outputs::Speaker::LowpassSpeaker<TI::SN76489> speaker_;
+		Yamaha::OPL2 opll_;
+		Outputs::Speaker::CompoundSource<TI::SN76489, Yamaha::OPL2> mixer_;
+		Outputs::Speaker::LowpassSpeaker<decltype(mixer_)> speaker_;
+		uint8_t opll_detection_word_ = 0xff;
 
 		std::vector<std::unique_ptr<Inputs::Joystick>> joysticks_;
 		Inputs::Keyboard keyboard_;
@@ -433,6 +472,9 @@ class ConcreteMachine:
 
 		uint8_t io_port_control_ = 0x0f;
 
+		// This is a static constexpr for now; I may use it in the future.
+		static constexpr bool has_fm_audio_ = true;
+
 		// The memory map has a 1kb granularity; this is determined by the SG1000's 1kb of RAM.
 		const uint8_t *read_pointers_[64];
 		uint8_t *write_pointers_[64];

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

@@ -785,6 +785,8 @@
 		4BC1317B2346DF2B00E4FF3D /* MSA.cpp in Sources */ = {isa = PBXBuildFile; fileRef = 4BC131782346DF2B00E4FF3D /* MSA.cpp */; };
 		4BC57CD92436A62900FBC404 /* State.cpp in Sources */ = {isa = PBXBuildFile; fileRef = 4BC57CD82436A62900FBC404 /* State.cpp */; };
 		4BC57CDA2436A62900FBC404 /* State.cpp in Sources */ = {isa = PBXBuildFile; fileRef = 4BC57CD82436A62900FBC404 /* State.cpp */; };
+		4BC57CE22436BFE000FBC404 /* OPL2.cpp in Sources */ = {isa = PBXBuildFile; fileRef = 4BC57CE02436BFE000FBC404 /* OPL2.cpp */; };
+		4BC57CE32436BFE000FBC404 /* OPL2.cpp in Sources */ = {isa = PBXBuildFile; fileRef = 4BC57CE02436BFE000FBC404 /* OPL2.cpp */; };
 		4BC5C3E022C994CD00795658 /* 68000MoveTests.mm in Sources */ = {isa = PBXBuildFile; fileRef = 4BC5C3DF22C994CC00795658 /* 68000MoveTests.mm */; };
 		4BC5FC3020CDDDEF00410AA0 /* AppleIIOptions.xib in Resources */ = {isa = PBXBuildFile; fileRef = 4BC5FC2E20CDDDEE00410AA0 /* AppleIIOptions.xib */; };
 		4BC751B21D157E61006C31D9 /* 6522Tests.swift in Sources */ = {isa = PBXBuildFile; fileRef = 4BC751B11D157E61006C31D9 /* 6522Tests.swift */; };
@@ -1659,6 +1661,8 @@
 		4BC57CD424342E0600FBC404 /* MachineTypes.hpp */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.cpp.h; path = MachineTypes.hpp; sourceTree = "<group>"; };
 		4BC57CD72436A61300FBC404 /* State.hpp */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.cpp.h; path = State.hpp; sourceTree = "<group>"; };
 		4BC57CD82436A62900FBC404 /* State.cpp */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.cpp.cpp; path = State.cpp; sourceTree = "<group>"; };
+		4BC57CE02436BFE000FBC404 /* OPL2.cpp */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.cpp.cpp; path = OPL2.cpp; sourceTree = "<group>"; };
+		4BC57CE12436BFE000FBC404 /* OPL2.hpp */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.cpp.h; path = OPL2.hpp; sourceTree = "<group>"; };
 		4BC5C3DF22C994CC00795658 /* 68000MoveTests.mm */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.cpp.objcpp; path = 68000MoveTests.mm; sourceTree = "<group>"; };
 		4BC5FC2F20CDDDEE00410AA0 /* Base */ = {isa = PBXFileReference; lastKnownFileType = file.xib; name = Base; path = "Clock Signal/Base.lproj/AppleIIOptions.xib"; sourceTree = SOURCE_ROOT; };
 		4BC751B11D157E61006C31D9 /* 6522Tests.swift */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.swift; path = 6522Tests.swift; sourceTree = "<group>"; };
@@ -3518,6 +3522,15 @@
 			path = State;
 			sourceTree = "<group>";
 		};
+		4BC57CDF2436BFE000FBC404 /* OPL2 */ = {
+			isa = PBXGroup;
+			children = (
+				4BC57CE02436BFE000FBC404 /* OPL2.cpp */,
+				4BC57CE12436BFE000FBC404 /* OPL2.hpp */,
+			);
+			path = OPL2;
+			sourceTree = "<group>";
+		};
 		4BC9DF4A1D04691600F44158 /* Components */ = {
 			isa = PBXGroup;
 			children = (
@@ -3537,6 +3550,7 @@
 				4B4A762D1DB1A35C007AAE2E /* AY38910 */,
 				4B302181208A550100773308 /* DiskII */,
 				4B4B1A39200198C900A0F866 /* KonamiSCC */,
+				4BC57CDF2436BFE000FBC404 /* OPL2 */,
 				4B0ACBFF237756EC008902D0 /* Serial */,
 				4BB0A6582044FD3000FB3688 /* SN76489 */,
 			);
@@ -4312,6 +4326,7 @@
 				4B894521201967B4007DE474 /* StaticAnalyser.cpp in Sources */,
 				4B8318B522D3E548006DB630 /* Macintosh.cpp in Sources */,
 				4B7BA03123C2B19C00B98D9E /* Jasmin.cpp in Sources */,
+				4BC57CE32436BFE000FBC404 /* OPL2.cpp in Sources */,
 				4B7F188F2154825E00388727 /* MasterSystem.cpp in Sources */,
 				4B055AA51FAE85EF0060FFFF /* Encoder.cpp in Sources */,
 				4BD5D2692199148100DDF17D /* ScanTargetGLSLFragments.cpp in Sources */,
@@ -4584,6 +4599,7 @@
 				4BEA52631DF339D7007E74F2 /* SoundGenerator.cpp in Sources */,
 				4BD67DD0209BF27B00AB2146 /* Encoder.cpp in Sources */,
 				4BAE495920328897004BE78E /* ZX8081OptionsPanel.swift in Sources */,
+				4BC57CE22436BFE000FBC404 /* OPL2.cpp in Sources */,
 				4B89451A201967B4007DE474 /* ConfidenceSummary.cpp in Sources */,
 				4BE0A3EE237BB170002AB46F /* ST.cpp in Sources */,
 				4B54C0C51F8D91D90050900F /* Keyboard.cpp in Sources */,

Outputs/Speaker/Implementation/SampleSource.hpp

@@ -53,6 +53,11 @@ class SampleSource {
 		*/
 		void set_sample_volume_range(std::int16_t volume) {
 		}
+
+		/*!
+			Indicates whether this component will write stereo samples.
+		*/
+		static constexpr bool get_is_stereo() { return false; }
 };
 
 }