Starts in the direction of audio support.

Components/DiskII/IWM.cpp

@@ -389,7 +389,7 @@ void IWM::propose_shift(uint8_t bit) {
 
 	shift_register_ = uint8_t((shift_register_ << 1) | bit);
 	if(shift_register_ & 0x80) {
-		if(data_register_ & 0x80) LOG("Byte missed");
+//		if(data_register_ & 0x80) LOG("Byte missed");
 		data_register_ = shift_register_;
 		shift_register_ = 0;
 	}

Machines/Apple/AppleIIgs/AppleIIgs.cpp

@@ -24,6 +24,7 @@
 #include "../../../Components/DiskII/IWM.hpp"
 #include "../../../Components/DiskII/MacintoshDoubleDensityDrive.hpp"
 
+#include "../../../Outputs/Speaker/Implementation/CompoundSource.hpp"
 #include "../../../Outputs/Speaker/Implementation/LowpassSpeaker.hpp"
 
 #include "../../Utility/MemoryFuzzer.hpp"
@@ -59,8 +60,10 @@ class ConcreteMachine:
 		 		{CLOCK_RATE / 2, true},
 		 		{CLOCK_RATE / 2, true}
 			},
+			sound_glu_(audio_queue_),
 			audio_toggle_(audio_queue_),
-			speaker_(audio_toggle_) {
+			mixer_(sound_glu_, audio_toggle_),
+			speaker_(mixer_) {
 
 			set_clock_rate(double(CLOCK_RATE));
 			speaker_.set_input_rate(float(CLOCK_RATE) / float(audio_divider));
@@ -738,14 +741,18 @@ class ConcreteMachine:
 		Apple::Macintosh::DoubleDensityDrive drives_[2];
 
 		// The audio parts.
-		Apple::IIgs::Sound::GLU sound_glu_;
 		Concurrency::DeferringAsyncTaskQueue audio_queue_;
+		Apple::IIgs::Sound::GLU sound_glu_;
 		Audio::Toggle audio_toggle_;
-		Outputs::Speaker::LowpassSpeaker<Audio::Toggle> speaker_;
+		using AudioSource = Outputs::Speaker::CompoundSource<Apple::IIgs::Sound::GLU, Audio::Toggle>;
+		AudioSource mixer_;
+		Outputs::Speaker::LowpassSpeaker<AudioSource> speaker_;
 		Cycles cycles_since_audio_update_;
 		static constexpr int audio_divider = 8;
 		void update_audio() {
-			speaker_.run_for(audio_queue_, cycles_since_audio_update_.divide(Cycles(audio_divider)));
+			const auto divided_cycles = cycles_since_audio_update_.divide(Cycles(audio_divider));
+			sound_glu_.run_for(divided_cycles);
+			speaker_.run_for(audio_queue_, divided_cycles);
 		}
 
 		// MARK: - Cards.

Machines/Apple/AppleIIgs/Sound.cpp

@@ -12,22 +12,64 @@
 
 using namespace Apple::IIgs::Sound;
 
-void GLU::set_control(uint8_t control) {
-//	printf("UNIMPLEMENTED: set control %02x\n", control);
-}
-
-uint8_t GLU::get_control() {
-	return 0;
-}
+GLU::GLU(Concurrency::DeferringAsyncTaskQueue &audio_queue) : audio_queue_(audio_queue) {}
 
 void GLU::set_data(uint8_t data) {
-//	printf("UNIMPLEMENTED: set data %02x\n", data);
+	if(control_ & 0x40) {
+		// RAM access.
+		local_.ram_[address_] = data;
+	} else {
+		// Register access.
+		switch(address_ & 0xe0) {
+			case 0x00:
+//				oscillators_[address_ & 0x1f].velocity = (oscillators_[address_ & 0x1f].velocity & 0xff00) | (data << 8);
+			break;
+			case 0x20:
+//				oscillators_[address_ & 0x1f].velocity = (oscillators_[address_ & 0x1f].velocity & 0x00ff) | (data << 8);
+			break;
+		}
+		printf("Register write %04x\n", address_);
+	}
+
+	if(control_ & 0x20) {
+		++address_;
+	}
 }
 
 uint8_t GLU::get_data() {
 	return 0;
 }
 
+// MARK: - Update logic.
+
+void GLU::run_for(Cycles cycles) {
+	// Update local state, without generating audio.
+}
+
+void GLU::get_samples(std::size_t number_of_samples, std::int16_t *target) {
+	// Update remote state, generating audio.
+}
+
+void GLU::skip_samples(const std::size_t number_of_samples) {
+	// Update remote state, without generating audio.
+}
+
+void GLU::set_sample_volume_range(std::int16_t range) {
+	// TODO
+}
+
+// MARK: - Interface boilerplate.
+
+void GLU::set_control(uint8_t control) {
+	control_ = control;
+
+	// Low three bits are volume control: this probably needs to be fed off-thrad?
+}
+
+uint8_t GLU::get_control() {
+	return control_;
+}
+
 void GLU::set_address_low(uint8_t low) {
 	address_ = uint16_t((address_ & 0xff00) | low);
 }

Machines/Apple/AppleIIgs/Sound.hpp

@@ -10,14 +10,17 @@
 #define Apple_IIgs_Sound_hpp
 
 #include "../../../ClockReceiver/ClockReceiver.hpp"
+#include "../../../Concurrency/AsyncTaskQueue.hpp"
+#include "../../../Outputs/Speaker/Implementation/SampleSource.hpp"
 
 namespace Apple {
 namespace IIgs {
 namespace Sound {
 
-class GLU {
-
+class GLU: public Outputs::Speaker::SampleSource {
 	public:
+		GLU(Concurrency::DeferringAsyncTaskQueue &audio_queue);
+
 		void set_control(uint8_t);
 		uint8_t get_control();
 		void set_data(uint8_t);
@@ -27,8 +30,35 @@ class GLU {
 		void set_address_high(uint8_t);
 		uint8_t get_address_high();
 
+		void run_for(Cycles);
+
+		// SampleSource.
+		void get_samples(std::size_t number_of_samples, std::int16_t *target);
+		void set_sample_volume_range(std::int16_t range);
+		void skip_samples(const std::size_t number_of_samples);
+
 	private:
+		Concurrency::DeferringAsyncTaskQueue &audio_queue_;
+
 		uint16_t address_ = 0;
+
+		struct EnsoniqState {
+			uint8_t ram_[65536];
+			struct Oscillator {
+				uint32_t position;
+
+				// Programmer-set values.
+				uint16_t velocity;
+				uint8_t volume;
+				uint8_t address;
+				uint8_t control;
+				uint8_t table_size;
+			} oscillators_[32];
+		} local_, remote_;
+		uint8_t interrupt_state_;
+		uint8_t oscillator_enable_;
+
+		uint8_t control_ = 0x00;
 };
 
 }