text: /*
    Copyright (c) 2011 Arduino.  All right reserved.
  
    This library is free software; you can redistribute it and/or
    modify it under the terms of the GNU Lesser General Public
    License as published by the Free Software Foundation; either
    version 2.1 of the License, or (at your option) any later version.
  
    This library is distributed in the hope that it will be useful,
    but WITHOUT ANY WARRANTY; without even the implied warranty of
    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. 
    See the GNU Lesser General Public License for more details.
  
    You should have received a copy of the GNU Lesser General Public
    License along with this library; if not, write to the Free Software
    Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
  */
  
  #ifndef _WIRING_DIGITAL_
  #define _WIRING_DIGITAL_
  
  #ifdef __cplusplus
   extern "C" {
  #endif
  
  /**
   * \brief Configures the specified pin to behave either as an input or an output. See the description of digital pins for details.
   *
   * \param ulPin The number of the pin whose mode you wish to set
   * \param ulMode Either INPUT or OUTPUT
   */
  extern void pinMode( uint32_t dwPin, uint32_t dwMode ) ;
  
  /**
   * \brief Write a HIGH or a LOW value to a digital pin.
   *
   * If the pin has been configured as an OUTPUT with pinMode(), its voltage will be set to the
   * corresponding value: 5V (or 3.3V on 3.3V boards) for HIGH, 0V (ground) for LOW.
   *
   * If the pin is configured as an INPUT, writing a HIGH value with digitalWrite() will enable an internal
   * 20K pullup resistor (see the tutorial on digital pins). Writing LOW will disable the pullup. The pullup
   * resistor is enough to light an LED dimly, so if LEDs appear to work, but very dimly, this is a likely
   * cause. The remedy is to set the pin to an output with the pinMode() function.
   *
   * \note Digital pin PIN_LED is harder to use as a digital input than the other digital pins because it has an LED
   * and resistor attached to it that's soldered to the board on most boards. If you enable its internal 20k pull-up
   * resistor, it will hang at around 1.7 V instead of the expected 5V because the onboard LED and series resistor
   * pull the voltage level down, meaning it always returns LOW. If you must use pin PIN_LED as a digital input, use an
   * external pull down resistor.
   *
   * \param dwPin the pin number
   * \param dwVal HIGH or LOW
   */
  extern void digitalWrite( uint32_t dwPin, uint32_t dwVal ) ;
  
  /**
   * \brief Reads the value from a specified digital pin, either HIGH or LOW.
   *
   * \param ulPin The number of the digital pin you want to read (int)
   *
   * \return HIGH or LOW
   */
  extern int digitalRead( uint32_t ulPin ) ;
  
  #ifdef __cplusplus
  }
  #endif
  
  #endif /* _WIRING_DIGITAL_ */
  