text: // Copyright 2014 Olivier Gillet.
  //
  // Author: Olivier Gillet (ol.gillet@gmail.com)
  //
  // Permission is hereby granted, free of charge, to any person obtaining a copy
  // of this software and associated documentation files (the "Software"), to deal
  // in the Software without restriction, including without limitation the rights
  // to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
  // copies of the Software, and to permit persons to whom the Software is
  // furnished to do so, subject to the following conditions:
  // 
  // The above copyright notice and this permission notice shall be included in
  // all copies or substantial portions of the Software.
  // 
  // THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  // IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  // FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
  // AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
  // LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
  // OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
  // THE SOFTWARE.
  // 
  // See http://creativecommons.org/licenses/MIT/ for more information.
  //
  // -----------------------------------------------------------------------------
  //
  // Driver for the gate inputs.
  
  #include "clouds/drivers/gate_input.h"
  
  #include <algorithm>
  
  namespace clouds {
  
  using namespace std;
  
  void GateInput::Init() {
    RCC_AHB1PeriphClockCmd(RCC_AHB1Periph_GPIOB, ENABLE);
    
    GPIO_InitTypeDef gpio_init;
    gpio_init.GPIO_Pin = GPIO_Pin_6 | GPIO_Pin_7;
    gpio_init.GPIO_Mode = GPIO_Mode_IN;
    gpio_init.GPIO_OType = GPIO_OType_PP;
    gpio_init.GPIO_Speed = GPIO_Speed_25MHz;
    gpio_init.GPIO_PuPd = GPIO_PuPd_UP;
    GPIO_Init(GPIOB, &gpio_init);
    freeze_ = false;
    trigger_ = false;
    previous_freeze_ = false;
    previous_trigger_ = false;
  }
  
  void GateInput::Read() {
    previous_freeze_ = freeze_;
    previous_trigger_ = trigger_;
    freeze_ = !GPIO_ReadInputDataBit(GPIOB, GPIO_Pin_7);
    trigger_ = !GPIO_ReadInputDataBit(GPIOB, GPIO_Pin_6);
  }
  
  }  // namespace clouds
  