text: /**
    ******************************************************************************
    * @file    DAC/OneChannel_NoiseWave/main.c 
    * @author  MCD Application Team
    * @version V3.1.2
    * @date    09/28/2009
    * @brief   Main program body.
    ******************************************************************************
    * @copy
    *
    * THE PRESENT FIRMWARE WHICH IS FOR GUIDANCE ONLY AIMS AT PROVIDING CUSTOMERS
    * WITH CODING INFORMATION REGARDING THEIR PRODUCTS IN ORDER FOR THEM TO SAVE
    * TIME. AS A RESULT, STMICROELECTRONICS SHALL NOT BE HELD LIABLE FOR ANY
    * DIRECT, INDIRECT OR CONSEQUENTIAL DAMAGES WITH RESPECT TO ANY CLAIMS ARISING
    * FROM THE CONTENT OF SUCH FIRMWARE AND/OR THE USE MADE BY CUSTOMERS OF THE
    * CODING INFORMATION CONTAINED HEREIN IN CONNECTION WITH THEIR PRODUCTS.
    *
    * <h2><center>&copy; COPYRIGHT 2009 STMicroelectronics</center></h2>
    */ 
  
  /* Includes ------------------------------------------------------------------*/
  #include "stm32f10x.h"
  
  /** @addtogroup STM32F10x_StdPeriph_Examples
    * @{
    */
  
  /** @addtogroup DAC_OneChannel_NoiseWave
    * @{
    */ 
  
  /* Private typedef -----------------------------------------------------------*/
  /* Private define ------------------------------------------------------------*/
  /* Init Structure definition */
  DAC_InitTypeDef            DAC_InitStructure;
  
  /* Private macro -------------------------------------------------------------*/
  /* Private variables ---------------------------------------------------------*/
  /* Private function prototypes -----------------------------------------------*/
  void RCC_Configuration(void);
  void GPIO_Configuration(void);
  void Delay(__IO uint32_t nCount);
  
  /* Private functions ---------------------------------------------------------*/
  
  /**
    * @brief   Main program.
    * @param  None
    * @retval None
    */
  int main(void)
  {
    /* System Clocks Configuration */
    RCC_Configuration();   
  
    /* Once the DAC channel is enabled, the corresponding GPIO pin is automatically 
       connected to the DAC converter. In order to avoid parasitic consumption, 
       the GPIO pin should be configured in analog */
    GPIO_Configuration();
  
    /* DAC channel1 Configuration */
    DAC_InitStructure.DAC_Trigger = DAC_Trigger_Software;
    DAC_InitStructure.DAC_WaveGeneration = DAC_WaveGeneration_Noise;
    DAC_InitStructure.DAC_LFSRUnmask_TriangleAmplitude = DAC_LFSRUnmask_Bits8_0;
    DAC_InitStructure.DAC_OutputBuffer = DAC_OutputBuffer_Enable;
    DAC_Init(DAC_Channel_1, &DAC_InitStructure);
  
    /* Enable DAC Channel1: Once the DAC channel1 is enabled, PA.04 is 
       automatically connected to the DAC converter. */
    DAC_Cmd(DAC_Channel_1, ENABLE);
  
    /* Set DAC Channel1 DHR12L register */
    DAC_SetChannel1Data(DAC_Align_12b_L, 0x7FF0);
  
    while (1)
    {
      /* Start DAC Channel1 conversion by software */
      DAC_SoftwareTriggerCmd(DAC_Channel_1, ENABLE);
    }
  }
  
  /**
    * @brief  Configures the different system clocks.
    * @param  None
    * @retval None
    */
  void RCC_Configuration(void)
  {   
    /* Setup the microcontroller system. Initialize the Embedded Flash Interface,  
       initialize the PLL and update the SystemFrequency variable. */
    SystemInit();
  
  /* Enable peripheral clocks --------------------------------------------------*/
    /* GPIOA Periph clock enable */
    RCC_APB2PeriphClockCmd(RCC_APB2Periph_GPIOA, ENABLE);
    /* DAC Periph clock enable */
    RCC_APB1PeriphClockCmd(RCC_APB1Periph_DAC, ENABLE);
  }
  
  /**
    * @brief  Configures the different GPIO ports.
    * @param  None
    * @retval None
    */
  void GPIO_Configuration(void)
  {
    GPIO_InitTypeDef GPIO_InitStructure;
  
    /* Once the DAC channel is enabled, the corresponding GPIO pin is automatically 
       connected to the DAC converter. In order to avoid parasitic consumption, 
       the GPIO pin should be configured in analog */
    GPIO_InitStructure.GPIO_Pin =  GPIO_Pin_4;
    GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AIN;
    GPIO_Init(GPIOA, &GPIO_InitStructure);
  }
  
  /**
    * @brief  Inserts a delay time.
    * @param  nCount: specifies the delay time length.
    * @retval None
    */
  void Delay(__IO uint32_t nCount)
  {
    for(; nCount != 0; nCount--);
  }
  
  #ifdef  USE_FULL_ASSERT
  
  /**
    * @brief  Reports the name of the source file and the source line number
    *   where the assert_param error has occurred.
    * @param  file: pointer to the source file name
    * @param  line: assert_param error line source number
    * @retval None
    */
  void assert_failed(uint8_t* file, uint32_t line)
  { 
    /* User can add his own implementation to report the file name and line number,
       ex: printf("Wrong parameters value: file %s on line %d\r\n", file, line) */
  
    /* Infinite loop */
    while (1)
    {
    }
  }
  #endif
  
  /**
    * @}
    */ 
  
  /**
    * @}
    */ 
  
  /******************* (C) COPYRIGHT 2009 STMicroelectronics *****END OF FILE****/
  