stm32正弦波数据产生函数

在STM32中产生正弦波可以使用DAC或者PWM输出模式，下面给出两种实现方式：

## 使用DAC

1. 配置DAC

DAC_HandleTypeDef hdac;

void MX_DAC_Init(void)
{
  DAC_ChannelConfTypeDef sConfig = {0};

  hdac.Instance = DAC1;
  if (HAL_DAC_Init(&hdac) != HAL_OK)
  {
    Error_Handler();
  }
  sConfig.DAC_Trigger = DAC_TRIGGER_NONE;
  sConfig.DAC_OutputBuffer = DAC_OUTPUTBUFFER_DISABLE;
  if (HAL_DAC_ConfigChannel(&hdac, &sConfig, DAC_CHANNEL_1) != HAL_OK)
  {
    Error_Handler();
  }

}

2. 产生正弦波数据

#define SAMPLE_NUM 100
#define PI 3.1415926f
uint16_t sineWave[SAMPLE_NUM];

void createSinWave(void)
{
  for(uint8_t i=0;i<SAMPLE_NUM;i++)
  {
    sineWave[i]=(uint16_t)(2048.0f*(1.0f+sinf(2.0f*PI*i/SAMPLE_NUM)));
  }
}

3. 启动DAC，并输出正弦波数据

void HAL_TIM_PeriodElapsedCallback(TIM_HandleTypeDef *htim)
{
  if (htim->Instance == TIM6)
  {
    HAL_DAC_Start(&hdac, DAC_CHANNEL_1);
    HAL_DAC_SetValue(&hdac, DAC_CHANNEL_1, DAC_ALIGN_12B_R, sineWave[counter]);
    counter++;
    if (counter >= SAMPLE_NUM) counter = 0;
  }
}

## 使用PWM

1. 配置PWM

TIM_HandleTypeDef htim2;

void MX_TIM2_Init(void)
{
  TIM_MasterConfigTypeDef sMasterConfig = {0};
  TIM_OC_InitTypeDef sConfigOC = {0};

  htim2.Instance = TIM2;
  htim2.Init.Prescaler = 0;
  htim2.Init.CounterMode = TIM_COUNTERMODE_UP;
  htim2.Init.Period = 799;
  htim2.Init.ClockDivision = TIM_CLOCKDIVISION_DIV1;
  if (HAL_TIM_PWM_Init(&htim2) != HAL_OK)
  {
    Error_Handler();
  }
  sMasterConfig.MasterOutputTrigger = TIM_TRGO_RESET;
  sMasterConfig.MasterSlaveMode = TIM_MASTERSLAVEMODE_DISABLE;
  if (HAL_TIMEx_MasterConfigSynchronization(&htim2, &sMasterConfig) != HAL_OK)
  {
    Error_Handler();
  }
  sConfigOC.OCMode = TIM_OCMODE_PWM1;
  sConfigOC.Pulse = 399;
  sConfigOC.OCPolarity = TIM_OCPOLARITY_HIGH;
  sConfigOC.OCFastMode = TIM_OCFAST_DISABLE;
  if (HAL_TIM_PWM_ConfigChannel(&htim2, &sConfigOC, TIM_CHANNEL_1) != HAL_OK)
  {
    Error_Handler();
  }
  HAL_TIM_MspPostInit(&htim2);

}

2. 产生正弦波数据

#define SAMPLE_NUM 100
#define PI 3.1415926f
uint16_t sineWave[SAMPLE_NUM];

void createSinWave(void)
{
  for(uint8_t i=0;i<SAMPLE_NUM;i++)
  {
    sineWave[i]=(uint16_t)(399.0f*(1.0f+sinf(2.0f*PI*i/SAMPLE_NUM)));
  }
}

3. 启动PWM，并输出正弦波数据

void HAL_TIM_PeriodElapsedCallback(TIM_HandleTypeDef *htim)
{
  if (htim->Instance == TIM6)
  {
    HAL_TIM_PWM_Start(&htim2, TIM_CHANNEL_1);
    __HAL_TIM_SET_COMPARE(&htim2, TIM_CHANNEL_1, sineWave[counter]);
    counter++;
    if (counter >= SAMPLE_NUM) counter = 0;
  }
}