DAC输出正弦波，单通道用不用填充正弦波

zslfighting1994

[mw_shl_code=c,true]#include "stm32f10x.h"

/** @addtogroup StdPeriph_Examples
  * @{
  */

/** @addtogroup DAC_DualModeDMA_SineWave
  * @{
  */

/* Private typedef -----------------------------------------------------------*/
/* Private define ------------------------------------------------------------*/
#define DAC_DHR12RD_Address      0x40007420

/* Init Structure definition */
DAC_InitTypeDef            DAC_InitStructure;
DMA_InitTypeDef            DMA_InitStructure;
TIM_TimeBaseInitTypeDef    TIM_TimeBaseStructure;

/* Private macro -------------------------------------------------------------*/
/* Private variables ---------------------------------------------------------*/
const uint16_t Sine12bit[32] = {2047, 2447, 2831, 3185, 3498, 3750, 3939, 4056, 4095, 4056,
                      3939, 3750, 3495, 3185, 2831, 2447, 2047, 1647, 1263, 909,
                      599, 344, 155, 38, 0, 38, 155, 344, 599, 909, 1263, 1647};

uint32_t DualSine12bit[32];
uint8_t Idx = 0;

/* 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();

  /* TIM8 Configuration */
  /* Time base configuration */
  TIM_TimeBaseStructInit(&TIM_TimeBaseStructure);
  TIM_TimeBaseStructure.TIM_Period =0x19;         
  TIM_TimeBaseStructure.TIM_Prescaler = 0x0;      
  TIM_TimeBaseStructure.TIM_ClockDivision = 0x0;   
  TIM_TimeBaseStructure.TIM_CounterMode = TIM_CounterMode_Up;  
  TIM_TimeBaseInit(TIM8, &TIM_TimeBaseStructure);

  /* TIM8 TRGO selection */
  TIM_SelectOutputTrigger(TIM8, TIM_TRGOSource_Update);

  /* DAC channel1 Configuration */
  DAC_InitStructure.DAC_Trigger = DAC_Trigger_T8_TRGO;
  DAC_InitStructure.DAC_WaveGeneration = DAC_WaveGeneration_None;
  DAC_InitStructure.DAC_OutputBuffer = DAC_OutputBuffer_Disable;
  DAC_Init(DAC_Channel_1, &DAC_InitStructure);

  /* DAC channel2 Configuration */
  DAC_Init(DAC_Channel_2, &DAC_InitStructure);

  /* Fill Sine32bit table */
  for (Idx= 0; Idx<32; Idx++)
  {
    DualSine12bit[Idx] = (Sine12bit[Idx] << 16) + (Sine12bit[Idx]);如果我不用双通道的话，是不是就不用写这段了？
  }

  /* DMA2 channel4 configuration */
  DMA_DeInit(DMA2_Channel4);
  DMA_InitStructure.DMA_PeripheralBaseAddr = DAC_DHR12RD_Address;
  DMA_InitStructure.DMA_MemoryBaseAddr = (uint32_t)&DualSine12bit;
  DMA_InitStructure.DMA_DIR = DMA_DIR_PeripheralDST;
  DMA_InitStructure.DMA_BufferSize = 32;
  DMA_InitStructure.DMA_PeripheralInc = DMA_PeripheralInc_Disable;
  DMA_InitStructure.DMA_MemoryInc = DMA_MemoryInc_Enable;
  DMA_InitStructure.DMA_PeripheralDataSize = DMA_PeripheralDataSize_Word;
  DMA_InitStructure.DMA_MemoryDataSize = DMA_MemoryDataSize_Word;
  DMA_InitStructure.DMA_Mode = DMA_Mode_Circular;
  DMA_InitStructure.DMA_Priority = DMA_Priority_High;
  DMA_InitStructure.DMA_M2M = DMA_M2M_Disable;
  DMA_Init(DMA2_Channel4, &DMA_InitStructure);

  /* Enable DMA2 Channel4 */
  DMA_Cmd(DMA2_Channel4, ENABLE);

  /* Enable DAC Channel1: Once the DAC channel1 is enabled, PA.04 is
     automatically connected to the DAC converter. */
  DAC_Cmd(DAC_Channel_1, ENABLE);
  /* Enable DAC Channel2: Once the DAC channel2 is enabled, PA.05 is
     automatically connected to the DAC converter. */
  DAC_Cmd(DAC_Channel_2, ENABLE);

  /* Enable DMA for DAC Channel2 */
  DAC_DMACmd(DAC_Channel_2, ENABLE);

  /* TIM8 enable counter */
  TIM_Cmd(TIM8, ENABLE);

  while (1)
  {
  }
}


/**
  * @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 --------------------------------------------------*/
  /* DMA clock enable */
  RCC_AHBPeriphClockCmd(RCC_AHBPeriph_DMA2, ENABLE);
  /* GPIOA Periph clock enable */
  RCC_APB2PeriphClockCmd(RCC_APB2Periph_GPIOA, ENABLE);
  /* DAC Periph clock enable */
  RCC_APB1PeriphClockCmd(RCC_APB1Periph_DAC, ENABLE);
  /* TIM8 Periph clock enable */
  RCC_APB2PeriphClockCmd(RCC_APB2Periph_TIM8, 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_Pin_5;
  GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AIN;
  GPIO_Init(GPIOA, &GPIO_InitStructure);
}
}
#endif
[/mw_shl_code]

1208

可以通过表格数据来描绘正弦波，可以参考下面的帖子看下
http://www.openedv.com/forum.php ... d=286617&extra=

zslfighting1994

1208 发表于 2019-3-18 15:28
可以通过表格数据来描绘正弦波，可以参考下面的帖子看下
http://www.openedv.com/forum.php?mod=viewthrea ...

好的，我看完了，我想问的是如果我用单通道的话，  for (Idx = 0; Idx < POINT_NUM; Idx++)
  {
       outdata = (Sine12bit[Idx] << 16) + (Sine12bit[Idx]);这句代码是不是不用写了？

1208

zslfighting1994 发表于 2019-3-18 16:48
好的，我看完了，我想问的是如果我用单通道的话，  for (Idx = 0; Idx < POINT_NUM; Idx++)
  {
       ...

要的，你可以试下看看

shichuang

zslfighting1994 发表于 2019-3-18 16:48
好的，我看完了，我想问的是如果我用单通道的话，  for (Idx = 0; Idx < POINT_NUM; Idx++)
  {
       ...

如果是用通道1的话，不用这个，如果是用通道2的话，只需把数据移到高16位即可，不用再加后面的数据