Enables AY audio, albeit underclocked.

Machines/Apple/AppleII/AppleII.cpp

@@ -61,40 +61,10 @@ constexpr int MockingboardSlot = 4;	// Conventional Mockingboard slot.
 //	* ... and hence seven pixels per memory access window clock in high-res mode, 14 in double high-res, etc.
 constexpr float master_clock = 14318180.0;
 
-class AYPair {
-	public:
-		AYPair(Concurrency::AsyncTaskQueue<false> &queue) :
-			ays_{
-				{GI::AY38910::Personality::AY38910, queue},
-				{GI::AY38910::Personality::AY38910, queue},
-			} {}
-
-		void advance() {
-			ays_[0].advance();
-			ays_[1].advance();
-		}
-
-		void set_sample_volume_range(std::int16_t range) {
-			ays_[0].set_sample_volume_range(range >> 1);
-			ays_[1].set_sample_volume_range(range >> 1);
-		}
-
-		bool is_zero_level() const {
-			return ays_[0].is_zero_level() && ays_[1].is_zero_level();
-		}
-
-		Outputs::Speaker::MonoSample level() const {
-			return ays_[0].level() + ays_[1].level();
-		}
-
-	private:
-		GI::AY38910::AY38910SampleSource<false> ays_[2];
-};
-
 /// Provides an AY that runs at the CPU rate divided by 4 given an input of the master clock divided by 2,
 /// allowing for stretched CPU clock cycles.
 struct StretchedAYPair:
-	AYPair,
+	Apple::II::AYPair,
 	public Outputs::Speaker::BufferSource<StretchedAYPair, false> {
 
 		using AYPair::AYPair;
@@ -681,7 +651,7 @@ template <Analyser::Static::AppleII::Target::Model model, bool has_mockingboard>
 			if(target.has_mockingboard) {
 				// The Mockingboard has a parasitic relationship with this class due to the way
 				// that audio outputs are implemented in this emulator.
-				install_card(MockingboardSlot, new Apple::II::Mockingboard());
+				install_card(MockingboardSlot, new Apple::II::Mockingboard(ays_));
 			}
 
 			rom_ = std::move(roms.find(system)->second);

Machines/Apple/AppleII/Mockingboard.hpp

@@ -12,15 +12,48 @@
 
 #include "../../../Components/6522/6522.hpp"
 
-
 namespace Apple::II {
 
+class AYPair {
+	public:
+		AYPair(Concurrency::AsyncTaskQueue<false> &queue) :
+			ays_{
+				{GI::AY38910::Personality::AY38910, queue},
+				{GI::AY38910::Personality::AY38910, queue},
+			} {}
+
+		void advance() {
+			ays_[0].advance();
+			ays_[1].advance();
+		}
+
+		void set_sample_volume_range(std::int16_t range) {
+			ays_[0].set_sample_volume_range(range >> 1);
+			ays_[1].set_sample_volume_range(range >> 1);
+		}
+
+		bool is_zero_level() const {
+			return ays_[0].is_zero_level() && ays_[1].is_zero_level();
+		}
+
+		Outputs::Speaker::MonoSample level() const {
+			return ays_[0].level() + ays_[1].level();
+		}
+
+		GI::AY38910::AY38910SampleSource<false> &get(int index) {
+			return ays_[index];
+		}
+
+	private:
+		GI::AY38910::AY38910SampleSource<false> ays_[2];
+};
+
 class Mockingboard: public Card {
 	public:
-		Mockingboard() :
+		Mockingboard(AYPair &ays) :
-			vias_{ {handlers_[0]}, {handlers_[1]} } {
+			vias_{ {handlers_[0]}, {handlers_[1]} },
+			handlers_{ {*this, ays.get(0)}, {*this, ays.get(1)}} {
 			set_select_constraints(0);
-			handlers_[0].card = handlers_[1].card = this;
 		}
 
 		void perform_bus_operation(Select select, bool is_read, uint16_t address, uint8_t *value) final {
@@ -55,13 +88,42 @@ class Mockingboard: public Card {
 
 	private:
 		struct AYVIA: public MOS::MOS6522::PortHandler {
+			AYVIA(Mockingboard &card, GI::AY38910::AY38910SampleSource<false> &ay) :
+				card(card), ay(ay) {}
+
 			void set_interrupt_status(bool status) {
 				interrupt = status;
-				card->did_change_interrupt_flags();
+				card.did_change_interrupt_flags();
+			}
+
+			void set_port_output(MOS::MOS6522::Port port, uint8_t value, uint8_t) {
+				if(port) {
+					using ControlLines = GI::AY38910::ControlLines;
+					ay.set_control_lines(
+						ControlLines(
+							((value & 1) ? ControlLines::BC1 : 0) |
+							((value & 2) ? ControlLines::BDIR : 0) |
+							((value & 4) ? ControlLines::BC2 : 0)
+						)
+					);
+
+					// TODO: all lines disabled sees to map to reset? Possibly?
+					// Cf. https://gswv.apple2.org.za/a2zine/Docs/Mockingboard_MiniManual.html
+				} else {
+					ay.set_data_input(value);
+				}
+			}
+
+			uint8_t get_port_input(MOS::MOS6522::Port port) {
+				if(!port) {
+					return ay.get_data_output();
+				}
+				return 0xff;
 			}
 
 			bool interrupt;
-			Mockingboard *card = nullptr;
+			Mockingboard &card;
+			GI::AY38910::AY38910SampleSource<false> &ay;
 		};
 
 		MOS::MOS6522::MOS6522<AYVIA> vias_[2];