text: /* mbed Microcontroller Library
   * Copyright (c) 2014, STMicroelectronics
   * All rights reserved.
   *
   * Redistribution and use in source and binary forms, with or without
   * modification, are permitted provided that the following conditions are met:
   *
   * 1. Redistributions of source code must retain the above copyright notice,
   *    this list of conditions and the following disclaimer.
   * 2. 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.
   * 3. Neither the name of STMicroelectronics nor the names of its contributors
   *    may be used to endorse or promote products derived from this software
   *    without specific prior written permission.
   *
   * 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.
   */
  #include "analogout_api.h"
  
  #if DEVICE_ANALOGOUT
  
  #include "cmsis.h"
  #include "pinmap.h"
  #include "error.h"
  
  #define RANGE_12BIT (0xFFF)
  
  static const PinMap PinMap_DAC[] = {
      {PA_4, DAC_1, STM_PIN_DATA(GPIO_Mode_AN, GPIO_OType_PP, GPIO_PuPd_NOPULL, 0xFF)}, // DAC_OUT1
      {NC,   NC,    0}
  };
  
  void analogout_init(dac_t *obj, PinName pin) {
      DAC_TypeDef *dac;
      DAC_InitTypeDef DAC_InitStructure;
  
      // Get the peripheral name (DAC_1, ...) from the pin and assign it to the object
      obj->dac = (DACName)pinmap_peripheral(pin, PinMap_DAC);
  
      if (obj->dac == (DACName)NC) {
          error("DAC pin mapping failed");
      }
  
      dac = (DAC_TypeDef *)(obj->dac);
  
      // Configure GPIO
      pinmap_pinout(pin, PinMap_DAC);
  
      // Save the channel for the write and read functions
      obj->channel = pin;
  
      // Enable DAC clock
      RCC_APB1PeriphClockCmd(RCC_APB1Periph_DAC, ENABLE);
  
      // Configure and enable DAC channel
      DAC_StructInit(&DAC_InitStructure);
      DAC_Init(dac, DAC_Channel_1, &DAC_InitStructure);
      DAC_Cmd(dac, DAC_Channel_1, ENABLE);
  
      analogout_write_u16(obj, 0);
  }
  
  void analogout_free(dac_t *obj) {
  }
  
  static inline void dac_write(dac_t *obj, uint16_t value) {
      DAC_TypeDef *dac = (DAC_TypeDef *)(obj->dac);
      DAC_SetChannel1Data(dac, DAC_Align_12b_R, value);
  }
  
  static inline int dac_read(dac_t *obj) {
      DAC_TypeDef *dac = (DAC_TypeDef *)(obj->dac);
      return (int)DAC_GetDataOutputValue(dac, DAC_Channel_1);
  }
  
  void analogout_write(dac_t *obj, float value) {
      if (value < 0.0f) {
          dac_write(obj, 0); // Min value
      } else if (value > 1.0f) {
          dac_write(obj, (uint16_t)RANGE_12BIT); // Max value
      } else {
          dac_write(obj, (uint16_t)(value * (float)RANGE_12BIT));
      }
  }
  
  void analogout_write_u16(dac_t *obj, uint16_t value) {
      if (value > (uint16_t)RANGE_12BIT) {
          dac_write(obj, (uint16_t)RANGE_12BIT); // Max value
      } else {
          dac_write(obj, value);
      }
  }
  
  float analogout_read(dac_t *obj) {
      uint32_t value = dac_read(obj);
      return (float)value * (1.0f / (float)RANGE_12BIT);
  }
  
  uint16_t analogout_read_u16(dac_t *obj) {
      return (uint16_t)dac_read(obj);
  }
  
  #endif // DEVICE_ANALOGOUT
  