wave.h

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/*
 * Copyright 2012-2015 Sebastian Neuser
 *
 * This file is part of the uMIDI firmware.
 *
 * The uMIDI firmware is free software: you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 *
 * The uMIDI firmware is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with the uMIDI firmware.  If not, see <http://www.gnu.org/licenses/>.
 */

#ifndef _WAVE_H
#define _WAVE_H


//---------------- includes ----------------//
#include <stdint.h>

#include "math.h"
#include "midi.h"


//---------------- code macros ----------------//

#define     RANDOM_WAVE_STEP_SIZE           4

#define     STAIR_WAVE_STEPS                5

#define     WAVE_STEPS                      100

#define     TAP_TEMPO_BUFFER_SIZE           3

#define     TAP_TEMPO_TASK_FREQUENCY        F_TASK_SLOW


//---------------- data types ----------------//

enum direction
{
    DIRECTION_DOWN,                             
    DIRECTION_UP,                               
};

enum waveform
{
    WAVE_OFF,                                   
    WAVE_SINE,                                  
    WAVE_TRIANGLE,                              
    WAVE_SAW_UP,                                
    WAVE_SAW_DOWN,                              
    WAVE_SQUARE,                                
    WAVE_STAIRS,                                
    WAVE_RANDOM,                                
};

struct wave_settings
{
    enum waveform   waveform;                   
    fixed_t         frequency;                  
    midi_value_t    amplitude;                  
    midi_value_t    offset;                     
};

struct wave_state
{
    uint16_t        speed_prescaler;            
    uint16_t        speed_counter;              
    uint8_t         step_counter;               
    enum direction  step_direction;             
};

struct wave
{
    struct wave_settings    settings;           
    struct wave_state       state;              
};


//---------------- functions and procedures ----------------//

void configure_tap_tempo_wave(struct wave * const wave);

void init_wave(struct wave* wave, enum waveform waveform, midi_value_t speed,
               midi_value_t amplitude, midi_value_t offset);

void register_tap(void);

void reset_wave(struct wave * const wave);

void set_frequency(struct wave* wave, fixed_t frequency);

void set_speed(struct wave* wave, midi_value_t speed);

void set_waveform(struct wave* wave, enum waveform waveform);

void tap_tempo_task(void);

midi_value_t update_wave(struct wave* wave);


//---------------- EOF ----------------//
#endif // _WAVE_H