text: /* mbed Microcontroller Library
   * Copyright (c) 2006-2013 ARM Limited
   *
   * Licensed under the Apache License, Version 2.0 (the "License");
   * you may not use this file except in compliance with the License.
   * You may obtain a copy of the License at
   *
   *     http://www.apache.org/licenses/LICENSE-2.0
   *
   * Unless required by applicable law or agreed to in writing, software
   * distributed under the License is distributed on an "AS IS" BASIS,
   * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
   * See the License for the specific language governing permissions and
   * limitations under the License.
   */
  #ifndef MBED_TIMER_H
  #define MBED_TIMER_H
  
  #include "platform.h"
  #include "ticker_api.h"
  
  namespace mbed {
  
  /** A general purpose timer
   *
   * @Note Synchronization level: Interrupt safe
   *
   * Example:
   * @code
   * // Count the time to toggle a LED
   *
   * #include "mbed.h"
   *
   * Timer timer;
   * DigitalOut led(LED1);
   * int begin, end;
   *
   * int main() {
   *     timer.start();
   *     begin = timer.read_us();
   *     led = !led;
   *     end = timer.read_us();
   *     printf("Toggle the led takes %d us", end - begin);
   * }
   * @endcode
   */
  class Timer {
  
  public:
      Timer();
      Timer(const ticker_data_t *data);
  
      /** Start the timer
       */
      void start();
  
      /** Stop the timer
       */
      void stop();
  
      /** Reset the timer to 0.
       *
       * If it was already counting, it will continue
       */
      void reset();
  
      /** Get the time passed in seconds
       */
      float read();
  
      /** Get the time passed in mili-seconds
       */
      int read_ms();
  
      /** Get the time passed in micro-seconds
       */
      int read_us();
  
  #ifdef MBED_OPERATORS
      operator float();
  #endif
  
  protected:
      int slicetime();
      int _running;          // whether the timer is running
      unsigned int _start;   // the start time of the latest slice
      int _time;             // any accumulated time from previous slices
      const ticker_data_t *_ticker_data;
  };
  
  } // namespace mbed
  
  #endif
  