mirror of
https://github.com/TomHarte/CLK.git
synced 2024-12-27 16:31:31 +00:00
48737a32a7
Previously every output device was making its own decision. Which is increasingly less sustainable due to the CompoundSource.
142 lines
3.8 KiB
C++
142 lines
3.8 KiB
C++
//
|
|
// AY-3-8910.hpp
|
|
// Clock Signal
|
|
//
|
|
// Created by Thomas Harte on 14/10/2016.
|
|
// Copyright © 2016 Thomas Harte. All rights reserved.
|
|
//
|
|
|
|
#ifndef AY_3_8910_hpp
|
|
#define AY_3_8910_hpp
|
|
|
|
#include "../../Outputs/Speaker/Implementation/SampleSource.hpp"
|
|
#include "../../Concurrency/AsyncTaskQueue.hpp"
|
|
|
|
namespace GI {
|
|
namespace AY38910 {
|
|
|
|
/*!
|
|
A port handler provides all input for an AY's two 8-bit ports, and may optionally receive
|
|
active notification of changes in output.
|
|
|
|
Machines with an AY without ports or with nothing wired to them need not supply a port handler.
|
|
Machines that use the AY ports as output but for which polling for changes is acceptable can
|
|
instead use AY38910.get_port_output.
|
|
*/
|
|
class PortHandler {
|
|
public:
|
|
/*!
|
|
Requests the current input on an AY port.
|
|
|
|
@param port_b @c true if the input being queried is Port B. @c false if it is Port A.
|
|
*/
|
|
virtual uint8_t get_port_input(bool port_b) {
|
|
return 0xff;
|
|
}
|
|
|
|
/*!
|
|
Requests the current input on an AY port.
|
|
|
|
@param port_b @c true if the input being queried is Port B. @c false if it is Port A.
|
|
*/
|
|
virtual void set_port_output(bool port_b, uint8_t value) {}
|
|
};
|
|
|
|
/*!
|
|
Names the control lines used as input to the AY, which uses CP1600 bus semantics.
|
|
*/
|
|
enum ControlLines {
|
|
BC1 = (1 << 0),
|
|
BC2 = (1 << 1),
|
|
BDIR = (1 << 2)
|
|
};
|
|
|
|
/*!
|
|
Provides emulation of an AY-3-8910 / YM2149, which is a three-channel sound chip with a
|
|
noise generator and a volume envelope generator, which also provides two bidirectional
|
|
interface ports.
|
|
*/
|
|
class AY38910: public ::Outputs::Speaker::SampleSource {
|
|
public:
|
|
/// Creates a new AY38910.
|
|
AY38910(Concurrency::DeferringAsyncTaskQueue &task_queue);
|
|
|
|
/// Sets the value the AY would read from its data lines if it were not outputting.
|
|
void set_data_input(uint8_t r);
|
|
|
|
/// Gets the value that would appear on the data lines if only the AY is outputting.
|
|
uint8_t get_data_output();
|
|
|
|
/// Sets the current control line state, as a bit field.
|
|
void set_control_lines(ControlLines control_lines);
|
|
|
|
/*!
|
|
Gets the value that would appear on the requested interface port if it were in output mode.
|
|
@parameter port_b @c true to get the value for Port B, @c false to get the value for Port A.
|
|
*/
|
|
uint8_t get_port_output(bool port_b);
|
|
|
|
/*!
|
|
Sets the port handler, which will receive a call every time the AY either wants to sample
|
|
input or else declare new output. As a convenience, current port output can be obtained
|
|
without installing a port handler via get_port_output.
|
|
*/
|
|
void set_port_handler(PortHandler *);
|
|
|
|
// to satisfy ::Outputs::Speaker (included via ::Outputs::Filter; not for public consumption
|
|
void get_samples(std::size_t number_of_samples, int16_t *target);
|
|
bool is_zero_level();
|
|
void set_sample_volume_range(std::int16_t range);
|
|
|
|
private:
|
|
Concurrency::DeferringAsyncTaskQueue &task_queue_;
|
|
|
|
int selected_register_ = 0;
|
|
uint8_t registers_[16];
|
|
uint8_t output_registers_[16] = {0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0};
|
|
uint8_t port_inputs_[2];
|
|
|
|
int master_divider_ = 0;
|
|
|
|
int tone_periods_[3] = {0, 0, 0};
|
|
int tone_counters_[3] = {0, 0, 0};
|
|
int tone_outputs_[3] = {0, 0, 0};
|
|
|
|
int noise_period_ = 0;
|
|
int noise_counter_ = 0;
|
|
int noise_shift_register_ = 0xffff;
|
|
int noise_output_ = 0;
|
|
|
|
int envelope_period_ = 0;
|
|
int envelope_divider_ = 0;
|
|
int envelope_position_ = 0;
|
|
int envelope_shapes_[16][32];
|
|
int envelope_overflow_masks_[16];
|
|
|
|
int volumes_[16];
|
|
|
|
enum ControlState {
|
|
Inactive,
|
|
LatchAddress,
|
|
Read,
|
|
Write
|
|
} control_state_;
|
|
|
|
void select_register(uint8_t r);
|
|
void set_register_value(uint8_t value);
|
|
uint8_t get_register_value();
|
|
|
|
uint8_t data_input_, data_output_;
|
|
|
|
int16_t output_volume_;
|
|
inline void evaluate_output_volume();
|
|
|
|
inline void update_bus();
|
|
PortHandler *port_handler_ = nullptr;
|
|
};
|
|
|
|
}
|
|
}
|
|
|
|
#endif /* AY_3_8910_hpp */
|