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CLK/Components/6560/6560.hpp

112 lines
2.8 KiB
C++

//
// 6560.hpp
// Clock Signal
//
// Created by Thomas Harte on 05/06/2016.
// Copyright © 2016 Thomas Harte. All rights reserved.
//
#ifndef _560_hpp
#define _560_hpp
#include "../../Outputs/CRT/CRT.hpp"
#include "../../Outputs/Speaker.hpp"
namespace MOS {
/*!
The 6560 is a video and audio output chip; it therefore vends both a @c CRT and a @c Speaker.
To run the 6560 for a cycle, the caller should call @c get_address, make the requested bus access
and call @c set_graphics_value with the result.
@c set_register and @c get_register provide register access.
*/
class MOS6560 {
public:
MOS6560();
Outputs::CRT::CRT *get_crt() { return _crt.get(); }
Outputs::Speaker *get_speaker() { return &_speaker; }
/*!
Impliedly runs the 6560 for a single cycle, returning the next address that it puts on the bus.
*/
uint16_t get_address();
/*!
An owning machine should determine the state of the data bus as a result of the access implied
by @c get_address and supply it to set_graphics_value.
*/
void set_graphics_value(uint8_t value, uint8_t colour_value);
/*!
Causes the 6560 to flush as much pending CRT and speaker communications as possible.
*/
inline void synchronise() { update_audio(); }
/*!
Writes to a 6560 register.
*/
void set_register(int address, uint8_t value);
/*
Reads from a 6560 register.
*/
uint8_t get_register(int address);
private:
std::unique_ptr<Outputs::CRT::CRT> _crt;
class Speaker: public ::Outputs::Filter<Speaker> {
public:
Speaker();
void set_volume(uint8_t volume);
void set_control(int channel, uint8_t value);
void get_samples(unsigned int number_of_samples, int16_t *target);
void skip_samples(unsigned int number_of_samples);
private:
unsigned int _counters[4];
unsigned int _shift_registers[4];
uint8_t _control_registers[4];
uint8_t _volume;
} _speaker;
bool _interlaced, _tall_characters;
uint8_t _first_column_location, _first_row_location;
uint8_t _number_of_columns, _number_of_rows;
uint16_t _character_cell_start_address, _video_matrix_start_address;
uint8_t _backgroundColour, _borderColour, _auxiliary_colour;
bool _invertedCells;
int _horizontal_counter, _vertical_counter;
bool _did_output_graphics;
int _column_counter, _row_counter;
uint16_t _video_matrix_address_counter, _video_matrix_line_address_counter;
enum State {
Sync, ColourBurst, Border, Pixels
} _this_state, _output_state;
unsigned int _cycles_in_state;
uint8_t _character_code, _character_colour, _character_value;
uint8_t *pixel_pointer;
uint8_t _registers[16];
uint8_t _colours[16];
bool _is_odd_frame;
void output_border(unsigned int number_of_cycles);
unsigned int _cycles_since_speaker_update;
void update_audio();
};
}
#endif /* _560_hpp */