actuator/AW9364LedDriver.hpp

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#pragma once
 
#include "../SensorBuildOpt.h"
#if !SENSORLIB_EXCLUDE_AW9364
 
#include "../expander/IoExpanderBase.hpp"
 
constexpr uint8_t MAX_BRIGHTNESS_STEPS = 16;
 
class AW9364LedDriver
{
public:
    void begin(uint8_t pin)
    {
        _driver_pin = pin;
        _base = nullptr;
        this->_pinMode(_driver_pin, OUTPUT);
        this->_digitalWrite(_driver_pin, LOW);
    }
 
    void begin(IoExpanderBase &base, uint8_t pin)
    {
        _base = &base;
        _driver_pin = pin;
        this->_pinMode(_driver_pin, OUTPUT);
        this->_digitalWrite(_driver_pin, LOW);
    }
 
    void setBrightness(uint8_t value)
    {
        if (_brightness == value) {
            return;
        }
        if (value > MAX_BRIGHTNESS_STEPS) {
            value = MAX_BRIGHTNESS_STEPS;
        }
 
        // Turn off if brightness is zero
        if (value == 0) {
            this->_digitalWrite(_driver_pin, 0);
            _brightness = 0;
            return;
        }
 
        // If coming from zero, start with a HIGH pulse to enable output
        if (_brightness == 0) {
            this->_digitalWrite(_driver_pin, 1);
            _brightness = MAX_BRIGHTNESS_STEPS;
        }
 
        // Calculate number of pulses needed to change from current brightness
        int from = MAX_BRIGHTNESS_STEPS - _brightness;
        int to   = MAX_BRIGHTNESS_STEPS - value;
        int num  = (MAX_BRIGHTNESS_STEPS + to - from) % MAX_BRIGHTNESS_STEPS;
 
        /*  // Optional speed boost when using I2C expanders
        //  uint32_t frequency = 0;
        //  if (_base) {
        //      // Increasing I2C speed may be necessary for enough pulse rate.
        //      // Tested with XL9555: can run at 1000 kHz despite 400 kHz spec.
        //      frequency = _base->getClock();
        //      _base->setClock(1000000UL);
        //  }
        */
 
        // Generate the required number of pulses
        for (int i = 0; i < num; i++) {
            this->_digitalWrite(_driver_pin, 0);
            this->_digitalWrite(_driver_pin, 1);
        }
 
        /*  // Restore original communication speed
        //  if (_base) {
        //      _base->setClock(frequency);
        //  }
        */
 
        _brightness = value;
    }
 
    uint8_t getBrightness() const
    {
        return _brightness;
    }
 
protected:
    void _pinMode(uint8_t pin, uint8_t mode)
    {
        if (_base) {
            _base->pinMode(pin, mode);
        } else {
            pinMode(pin, mode);
        }
    }
 
    void _digitalWrite(uint8_t pin, uint8_t value)
    {
        if (_base) {
            _base->digitalWrite(pin, value);
        } else {
            digitalWrite(pin, value);
        }
    }
 
private:
    IoExpanderBase *_base;          
    uint8_t _driver_pin;             
    uint8_t _brightness = 0;         
};
 
#endif