Phasor.h

/*
 * Phasor.h
 *
 * This file is part of Mozzi.
 *
 * Copyright 2012-2024 Tim Barrass and the Mozzi Team
 *
 * Mozzi is licensed under the GNU Lesser General Public Licence (LGPL) Version 2.1 or later.
 *
 */
 
#ifndef PHASOR_H_
#define PHASOR_H_
 
#include "Arduino.h"
#include "mozzi_fixmath.h"
 
#define PHASOR_MAX_VALUE_UL 4294967295UL
 
template <unsigned int UPDATE_RATE>
class Phasor
{
private:
    uint32_t current_value;
    volatile uint32_t step_size;
 
public:
    Phasor (){
        ;
    }
 
    inline
    uint32_t next()
    {
        current_value += step_size; // will wrap
        return current_value;
    }
 
    inline
    void set(uint32_t value)
    {
        current_value=value;
    }
 
 
    inline
    void setFreq( int frequency)
    {
        step_size = ((((uint32_t)((PHASOR_MAX_VALUE_UL>>8)+1))/(UPDATE_RATE))*frequency)<<8;
    }
 
 
    inline
    void setFreq(float frequency)
    { // 1 us - using float doesn't seem to incur measurable overhead with the oscilloscope
        step_size = (uint32_t)(((float)PHASOR_MAX_VALUE_UL/UPDATE_RATE)*frequency);
    }
 
    inline
    uint32_t phaseIncFromFreq(int frequency)
    {
        return ((((uint32_t)((PHASOR_MAX_VALUE_UL>>8)+1))/(UPDATE_RATE))*frequency)<<8;
    }
 
 
    inline
    void setPhaseInc(uint32_t stepsize)
    {
        step_size = stepsize;
    }
 
};
 
#endif /* PHASOR_H_ */