Merge pull request #363 from TomHarte/ZonX

Introduces ZonX emulation and corrects a minor ColecoVision AY timing issue.

Machines/ColecoVision/ColecoVision.cpp

@@ -252,6 +252,7 @@ class ConcreteMachine:
 								default: *cycle.value = 0xff; break;
 								case 0x52:
 									// Read AY data.
+									update_audio();
 									ay_.set_control_lines(GI::AY38910::ControlLines(GI::AY38910::BC2 | GI::AY38910::BC1));
 									*cycle.value = ay_.get_data_output();
 									ay_.set_control_lines(GI::AY38910::ControlLines(0));
@@ -289,12 +290,14 @@ class ConcreteMachine:
 								break;
 								case 0x50:
 									// Set AY address.
+									update_audio();
 									ay_.set_control_lines(GI::AY38910::BC1);
 									ay_.set_data_input(*cycle.value);
 									ay_.set_control_lines(GI::AY38910::ControlLines(0));
 								break;
 								case 0x51:
 									// Set AY data.
+									update_audio();
 									ay_.set_control_lines(GI::AY38910::ControlLines(GI::AY38910::BC2 | GI::AY38910::BDIR));
 									ay_.set_data_input(*cycle.value);
 									ay_.set_control_lines(GI::AY38910::ControlLines(0));

Machines/ZX8081/ZX8081.cpp

@@ -8,6 +8,7 @@
 
 #include "ZX8081.hpp"
 
+#include "../../Components/AY38910/AY38910.hpp"
 #include "../../Processors/Z80/Z80.hpp"
 #include "../../Storage/Tape/Tape.hpp"
 #include "../../Storage/Tape/Parsers/ZX8081.hpp"
@@ -18,6 +19,8 @@
 #include "../Utility/MemoryFuzzer.hpp"
 #include "../Utility/Typer.hpp"
 
+#include "../../Outputs/Speaker/Implementation/LowpassSpeaker.hpp"
+
 #include "Keyboard.hpp"
 #include "Video.hpp"
 
@@ -31,6 +34,11 @@ namespace {
 	const unsigned int ZX8081ClockRate = 3250000;
 }
 
+// TODO:
+//	Quiksilva sound support:
+//  7FFFh.W   PSG index
+//  7FFEh.R/W PSG data
+
 namespace ZX8081 {
 
 enum ROMType: uint8_t {
@@ -50,14 +58,18 @@ template<bool is_zx81> class ConcreteMachine:
 	public:
 		ConcreteMachine() :
 			z80_(*this),
-			tape_player_(ZX8081ClockRate) {
+			tape_player_(ZX8081ClockRate),
+			ay_(audio_queue_),
+			speaker_(ay_) {
 			set_clock_rate(ZX8081ClockRate);
+			speaker_.set_input_rate(static_cast<float>(ZX8081ClockRate) / 2.0f);
 			clear_all_keys();
 		}
 
 		forceinline HalfCycles perform_machine_cycle(const CPU::Z80::PartialMachineCycle &cycle) {
-			HalfCycles previous_counter = horizontal_counter_;
+			const HalfCycles previous_counter = horizontal_counter_;
 			horizontal_counter_ += cycle.length;
+			time_since_ay_update_ += cycle.length;
 
 			if(previous_counter < vsync_start_ && horizontal_counter_ >= vsync_start_) {
 				video_->run_for(vsync_start_ - previous_counter);
@@ -94,7 +106,7 @@ template<bool is_zx81> class ConcreteMachine:
 				return Cycles(0);
 			}
 
-			uint16_t address = cycle.address ? *cycle.address : 0;
+			const uint16_t address = cycle.address ? *cycle.address : 0;
 			bool is_opcode_read = false;
 			switch(cycle.operation) {
 				case CPU::Z80::PartialMachineCycle::Output:
@@ -106,6 +118,15 @@ template<bool is_zx81> class ConcreteMachine:
 						if(vsync_) line_counter_ = 0;
 						set_vsync(false);
 					}
+
+					// The below emulates the ZonX AY expansion device.
+					if(is_zx81) {
+						if((address&0xef) == 0xcf) {
+							ay_set_register(*cycle.value);
+						} else if((address&0xef) == 0x0f) {
+							ay_set_data(*cycle.value);
+						}
+					}
 				break;
 
 				case CPU::Z80::PartialMachineCycle::Input: {
@@ -121,6 +142,13 @@ template<bool is_zx81> class ConcreteMachine:
 
 						value &= ~(tape_player_.get_input() ? 0x00 : 0x80);
 					}
+
+					// The below emulates the ZonX AY expansion device.
+					if(is_zx81) {
+						if((address&0xef) == 0x0f) {
+							value &= ay_read_data();
+						}
+					}
 					*cycle.value = value;
 				} break;
 
@@ -144,7 +172,7 @@ template<bool is_zx81> class ConcreteMachine:
 					}
 					if(has_latched_video_byte_) {
 						std::size_t char_address = static_cast<std::size_t>((address & 0xfe00) | ((latched_video_byte_ & 0x3f) << 3) | line_counter_);
-						uint8_t mask = (latched_video_byte_ & 0x80) ? 0x00 : 0xff;
+						const uint8_t mask = (latched_video_byte_ & 0x80) ? 0x00 : 0xff;
 						if(char_address < ram_base_) {
 							latched_video_byte_ = rom_[char_address & rom_mask_] ^ mask;
 						} else {
@@ -159,10 +187,10 @@ template<bool is_zx81> class ConcreteMachine:
 				case CPU::Z80::PartialMachineCycle::ReadOpcode:
 					// Check for use of the fast tape hack.
 					if(use_fast_tape_hack_ && address == tape_trap_address_) {
-						uint64_t prior_offset = tape_player_.get_tape()->get_offset();
+						const uint64_t prior_offset = tape_player_.get_tape()->get_offset();
-						int next_byte = parser_.get_next_byte(tape_player_.get_tape());
+						const int next_byte = parser_.get_next_byte(tape_player_.get_tape());
 						if(next_byte != -1) {
-							uint16_t hl = z80_.get_value_of_register(CPU::Z80::Register::HL);
+							const uint16_t hl = z80_.get_value_of_register(CPU::Z80::Register::HL);
 							ram_[hl & ram_mask_] = static_cast<uint8_t>(next_byte);
 							*cycle.value = 0x00;
 							z80_.set_value_of_register(CPU::Z80::Register::ProgramCounter, tape_return_address_ - 1);
@@ -187,7 +215,7 @@ template<bool is_zx81> class ConcreteMachine:
 					if(address < ram_base_) {
 						*cycle.value = rom_[address & rom_mask_];
 					} else {
-						uint8_t value = ram_[address & ram_mask_];
+						const uint8_t value = ram_[address & ram_mask_];
 
 						// If this is an M1 cycle reading from above the 32kb mark and HALT is not
 						// currently active, latch for video output and return a NOP. Otherwise,
@@ -210,12 +238,15 @@ template<bool is_zx81> class ConcreteMachine:
 			}
 
 			if(typer_) typer_->run_for(cycle.length);
-
 			return HalfCycles(0);
 		}
 
 		forceinline void flush() {
 			video_->flush();
+			if(is_zx81) {
+				update_audio();
+				audio_queue_.perform();
+			}
 		}
 
 		void setup_output(float aspect_ratio) override final {
@@ -231,7 +262,7 @@ template<bool is_zx81> class ConcreteMachine:
 		}
 
 		Outputs::Speaker::Speaker *get_speaker() override final {
-			return nullptr;
+			return is_zx81 ? &speaker_ : nullptr;
 		}
 
 		void run_for(const Cycles cycles) override final {
@@ -301,7 +332,7 @@ template<bool is_zx81> class ConcreteMachine:
 
 		// Obtains the system ROMs.
 		bool set_rom_fetcher(const std::function<std::vector<std::unique_ptr<std::vector<uint8_t>>>(const std::string &machine, const std::vector<std::string> &names)> &roms_with_names) override {
-			auto roms = roms_with_names(
+			const auto roms = roms_with_names(
 				"ZX8081",
 				{
 					"zx80.rom",	"zx81.rom",
@@ -320,8 +351,8 @@ template<bool is_zx81> class ConcreteMachine:
 		}
 
 		// MARK: - Keyboard
-		void set_key_state(uint16_t key, bool isPressed) override final {
+		void set_key_state(uint16_t key, bool is_pressed) override final {
-			if(isPressed)
+			if(is_pressed)
 				key_states_[key >> 8] &= static_cast<uint8_t>(~key);
 			else
 				key_states_[key >> 8] |= static_cast<uint8_t>(key);
@@ -443,6 +474,34 @@ template<bool is_zx81> class ConcreteMachine:
 		inline void update_sync() {
 			video_->set_sync(vsync_ || hsync_);
 		}
+
+		// MARK: - Audio
+		Concurrency::DeferringAsyncTaskQueue audio_queue_;
+		GI::AY38910::AY38910 ay_;
+		Outputs::Speaker::LowpassSpeaker<GI::AY38910::AY38910> speaker_;
+		HalfCycles time_since_ay_update_;
+		inline void ay_set_register(uint8_t value) {
+			update_audio();
+			ay_.set_control_lines(GI::AY38910::BC1);
+			ay_.set_data_input(value);
+			ay_.set_control_lines(GI::AY38910::ControlLines(0));
+		}
+		inline void ay_set_data(uint8_t value) {
+			update_audio();
+			ay_.set_control_lines(GI::AY38910::ControlLines(GI::AY38910::BC2 | GI::AY38910::BDIR));
+			ay_.set_data_input(value);
+			ay_.set_control_lines(GI::AY38910::ControlLines(0));
+		}
+		inline uint8_t ay_read_data() {
+			update_audio();
+			ay_.set_control_lines(GI::AY38910::ControlLines(GI::AY38910::BC2 | GI::AY38910::BC1));
+			const uint8_t value = ay_.get_data_output();
+			ay_.set_control_lines(GI::AY38910::ControlLines(0));
+			return value;
+		}
+		inline void update_audio() {
+			speaker_.run_for(audio_queue_, time_since_ay_update_.divide_cycles(Cycles(2)));
+		}
 };
 
 }

OSBindings/SDL/main.cpp

@@ -460,12 +460,35 @@ int main(int argc, char *argv[]) {
 
 				// deliberate fallthrough...
 				case SDL_KEYUP: {
-					KeyboardMachine::Machine *keyboard_machine = machine->keyboard_machine();
+					const bool is_pressed = event.type == SDL_KEYDOWN;
-					if(!keyboard_machine) break;
 
+					KeyboardMachine::Machine *const keyboard_machine = machine->keyboard_machine();
+					if(keyboard_machine) {
 						Inputs::Keyboard::Key key = Inputs::Keyboard::Key::Space;
 						if(!KeyboardKeyForSDLScancode(event.key.keysym.scancode, key)) break;
-					keyboard_machine->get_keyboard().set_key_pressed(key, event.type == SDL_KEYDOWN);
+						keyboard_machine->get_keyboard().set_key_pressed(key, is_pressed);
+						break;
+					}
+
+					JoystickMachine::Machine *const joystick_machine = machine->joystick_machine();
+					if(joystick_machine) {
+						std::vector<std::unique_ptr<Inputs::Joystick>> &joysticks = joystick_machine->get_joysticks();
+						if(!joysticks.empty()) {
+							switch(event.key.keysym.scancode) {
+								case SDL_SCANCODE_LEFT:		joysticks[0]->set_digital_input(Inputs::Joystick::DigitalInput::Left, is_pressed);	break;
+								case SDL_SCANCODE_RIGHT:	joysticks[0]->set_digital_input(Inputs::Joystick::DigitalInput::Right, is_pressed);	break;
+								case SDL_SCANCODE_UP:		joysticks[0]->set_digital_input(Inputs::Joystick::DigitalInput::Up, is_pressed);	break;
+								case SDL_SCANCODE_DOWN:		joysticks[0]->set_digital_input(Inputs::Joystick::DigitalInput::Down, is_pressed);	break;
+								case SDL_SCANCODE_SPACE:	joysticks[0]->set_digital_input(Inputs::Joystick::DigitalInput::Fire, is_pressed);	break;
+								case SDL_SCANCODE_A:		joysticks[0]->set_digital_input(Inputs::Joystick::DigitalInput(Inputs::Joystick::DigitalInput::Fire, 0), is_pressed);	break;
+								case SDL_SCANCODE_S:		joysticks[0]->set_digital_input(Inputs::Joystick::DigitalInput(Inputs::Joystick::DigitalInput::Fire, 1), is_pressed);	break;
+								default: {
+									const char *key_name = SDL_GetKeyName(event.key.keysym.sym);
+									joysticks[0]->set_digital_input(Inputs::Joystick::DigitalInput(key_name[0]), is_pressed);
+								} break;
+							}
+						}
+					}
 				} break;
 
 				default: break;

README.md

@@ -13,6 +13,7 @@ It currently contains emulations of the:
 * Acorn Electron;
 * Amstrad CPC;
 * Atari 2600;
+* ColecoVision;
 * Commodore Vic-20 (and Commodore 1540/1);
 * MSX 1;
 * Oric 1/Atmos; and
@@ -43,6 +44,7 @@ If your machine has a 4k monitor and a 96Khz audio output? Then you'll get a 4k
 |![Repton 3 in game, with a classic 1:1 pixel emulation](READMEImages/NaiveRepton3.png)|![Repton 3 in game, decoded from an interlaced composite feed](READMEImages/CompositeRepton3.png)|
 |![Stormlord with a classic 1:1 pixel emulation](READMEImages/NaiveStormlord.png)|![Stormlord decoded from a composite feed](READMEImages/CompositeStormlord.png)|
 |![Road Fighter with a classic 1:1 pixel emulation](READMEImages/NaiveRoadFighter.png)|![Road Fighter decoded from a composite feed](READMEImages/CompositeRoadFighter.png)|
+|![A segment of the ColecoVision Donkey Kong title screen with a classic 1:1 pixel emulation](READMEImages/NaivePresentsDonkeyKong.png)|![A segment of the ColecoVision Donkey Kong title screen decoded from a composite feed](READMEImages/CompositePresentsDonkeyKong.png)|
 
 | 1:1 Pixel Copying | Correct Aspect Ratio, Filtered |
 |---|---|
@@ -65,7 +67,7 @@ Cycle-accurate emulation for the supported target machines is fairly trite; this
 
 Self-ratings:
 * the Electron, Oric and Vic-20 are pretty much perfect;
-* the ZX80, ZX81 and MSX 1 are very strong;
+* the ZX80, ZX81, ColecoVision and MSX 1 are very strong;
 * the Amstrad CPC has known accuracy deficiencies in its 8272 and 6845;
 * the Atari 2600 has some known accuracy deficiencies in its TIA;
 * the C-1540(/1) is locked in reading mode and doesn't yet support writing.