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/*
 * This sketch use different Hardware PWMs for LED Blue and Red
 * running with different frequency
 * - PWM0 : clock/1  ~ 16Mhz
 * - PWM1 : clock/16  ~ 1Mhz 
 *  
 * While LED RED looks solid, LED BLUE will blink while fading 
 * (due to its lower freq). Furthermore LED RED is inverted 
 * compared to LED BLUE (PWM2) --> They fade in opposite direction. 
 */

#include <Arduino.h>

/**************************************************************************/
/*!
    @brief  The setup function runs once when reset the board
*/
/**************************************************************************/
void setup()
{  
  // Add LED RED to PWM0
  HwPWM0.addPin( LED_RED );

  // Add LED BLUE to PWM1
  HwPWM1.addPin( LED_BLUE );

  // Enable PWM modules with 15-bit resolutions(max) but different clock div
  HwPWM0.begin();
  HwPWM0.setResolution(15);
  HwPWM0.setClockDiv(PWM_PRESCALER_PRESCALER_DIV_1); // freq = 16Mhz
  
  HwPWM1.begin();
  HwPWM1.setResolution(15);
  HwPWM1.setClockDiv(PWM_PRESCALER_PRESCALER_DIV_16); // freq = 1Mhz
}

/**************************************************************************/
/*!
    @brief  The loop function runs over and over again forever
*/
/**************************************************************************/
void loop()
{
  const int maxValue = bit(15) - 1;
  
  // fade in from min to max
  for (int fadeValue = 0 ; fadeValue <= maxValue; fadeValue += 1024) 
  {
    // Write same value but inverted for Led Blue
    HwPWM0.writePin(LED_RED, fadeValue, false);
    HwPWM1.writePin(LED_BLUE, fadeValue, true);
        
    // wait for 30 milliseconds to see the dimming effect
    delay(30);
  }

  // fade out from max to min
  for (int fadeValue = maxValue ; fadeValue >= 0; fadeValue -= 1024) 
  {  
    // Write same value but inverted for Led Blue
    HwPWM0.writePin(LED_RED, fadeValue, false);
    HwPWM1.writePin(LED_BLUE, fadeValue, true);
    
    // wait for 30 milliseconds to see the dimming effect
    delay(30);
  }
}