text: /*******************************************************************************
  * Copyright (c) 2018 Elhay Rauper
  * All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted (subject to the limitations in the disclaimer
  * below) provided that the following conditions are met:
  *
  *     * Redistributions of source code must retain the above copyright notice,
  *     this list of conditions and the following disclaimer.
  *
  *     * Redistributions in binary form must reproduce the above copyright
  *     notice, this list of conditions and the following disclaimer in the
  *     documentation and/or other materials provided with the distribution.
  *
  *     * Neither the name of the copyright holder nor the names of its
  *     contributors may be used to endorse or promote products derived from this
  *     software without specific prior written permission.
  *
  * NO EXPRESS OR IMPLIED LICENSES TO ANY PARTY'S PATENT RIGHTS ARE GRANTED BY
  * THIS LICENSE. THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND
  * CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A
  * PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR
  * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
  * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
  * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR
  * BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER
  * IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
  * POSSIBILITY OF SUCH DAMAGE.
  *******************************************************************************/
  
  #ifndef SAND_TIMER_H
  #define SAND_TIMER_H
  #include <Arduino.h>
  
  class SandTimer
  {
  private:
      unsigned long start_time_ = 0;
      unsigned long end_time_ = 0;
      unsigned long period_ = 0;
      bool started_ = false;
  
  public:
      SandTimer();
      void start(unsigned long period);
      void start();
      void setPeriod(unsigned long period);
      void startOver();
      bool finished();
      void reset();
      bool isRunning();
  };
  
  #endif
  