ESP32PWM.h

Go to the documentation of this file.

/*
 * ESP32PWM.h
 *
 *  Created on: Sep 22, 2018
 *      Author: hephaestus
 */

#ifndef LIBRARIES_ESP32SERVO_SRC_ESP32PWM_H_
#define LIBRARIES_ESP32SERVO_SRC_ESP32PWM_H_
#include "esp32-hal-ledc.h"
#define NUM_PWM 16
#define PWM_BASE_INDEX 0
#define USABLE_ESP32_PWM (NUM_PWM-PWM_BASE_INDEX)
#include <cstdint>

#include "Arduino.h"
class ESP32PWM {
private:

    void attach(int pin);
    int pwmChannel = 0;                         // channel number for this servo
    bool attachedState = false;
    int pin;
    uint8_t resolutionBits;
    double myFreq;
    int allocatenext(double freq);

    static double _ledcSetupTimerFreq(uint8_t chan, double freq,
            uint8_t bit_num);

    bool checkFrequencyForSideEffects(double freq);

    void adjustFrequencyLocal(double freq, float dutyScaled);
    static float mapf(float x, float in_min, float in_max, float out_min,
            float out_max) {
        if(x>in_max)
            return out_max;
        if(x<in_min)
            return out_min;
        return (x - in_min) * (out_max - out_min) / (in_max - in_min) + out_min;
    }

    double setup(double freq, uint8_t resolution_bits=10);
    //channel 0-15 resolution 1-16bits freq limits depend on resolution9
    void attachPin(uint8_t pin);
    // pin allocation
    void deallocate();
public:
    // setup
    ESP32PWM();
    virtual ~ESP32PWM();


    void detachPin(int pin);
    void attachPin(uint8_t pin, double freq, uint8_t resolution_bits=10);
    bool attached() {
        return attachedState;
    }

    // write raw duty cycle
    void write(uint32_t duty);
    // Write a duty cycle to the PWM using a unit vector from 0.0-1.0
    void writeScaled(float duty);
    //Adjust frequency
    double writeTone(double freq);
    double writeNote(note_t note, uint8_t octave);
    void adjustFrequency(double freq, float dutyScaled=-1);

    // Read pwm data
    uint32_t read();
    double readFreq();
    float getDutyScaled();

    //Timer data
    static int timerAndIndexToChannel(int timer, int index);
    static void allocateTimer(int timerNumber);
    static bool explicateAllocationMode;
    int getTimer() {
        return timerNum;
    }
    int timerNum = -1;
    uint32_t myDuty = 0;
    int getChannel();
    static int PWMCount;              // the total number of attached pwm
    static int timerCount[4];
    static ESP32PWM * ChannelUsed[NUM_PWM]; // used to track whether a channel is in service
    static long timerFreqSet[4];

    // Helper functions
    int getPin() {
        return pin;
    }
    static bool hasPwm(int pin) {
        if ((pin == 2) || //1
                (pin == 4) || //1
                (pin == 5) || //1
                ((pin >= 12) && (pin <= 19)) || //8
                ((pin >= 21) && (pin <= 23)) || //3
                ((pin >= 25) && (pin <= 27)) || //3
                (pin == 32) || (pin == 33)) //2
            return true;
        return false;
    }
    static int channelsRemaining() {
        return NUM_PWM - PWMCount;
    }


};

ESP32PWM* pwmFactory(int pin);

#endif /* LIBRARIES_ESP32SERVO_SRC_ESP32PWM_H_ */