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DAC ​

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c
void dac_init(void)
{
    DAC_ChannelConfTypeDef dac_ch_conf;

    g_dac_handle.Instance = DAC;
    HAL_DAC_Init(&g_dac_handle);                                        /* 初始化DAC */

    dac_ch_conf.DAC_Trigger = DAC_TRIGGER_NONE;                         /* 不使用触发功能,设置为自动触发 */
    dac_ch_conf.DAC_OutputBuffer = DAC_OUTPUTBUFFER_DISABLE;            /* DAC输出缓冲关闭 */

    HAL_DAC_ConfigChannel(&g_dac_handle, &dac_ch_conf, DAC_CHANNEL_1);  /* 配置DAC通道1 */
    HAL_DAC_Start(&g_dac_handle, DAC_CHANNEL_1);                        /* 开启DAC通道1 */
}

使用外部触发 ​

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c
dac_ch_conf.DAC_Trigger = DAC_TRIGGER_T7_TRGO;		//设置为定时器7触发
dac_ch_conf.DAC_OutputBuffer = DAC_OUTPUTBUFFER_DISABLE;	//不使能缓冲
HAL_DAC_ConfigChannel(&g_dac_dma_handle, &dac_ch_conf, DAC_CHANNEL_1);
c
/**
 * @brief       DAC DMA使能波形输出
 *   @note      TIM7的输入时钟频率(f)来自APB1, f = 36M * 2 = 72Mhz.
 *              DAC触发频率 ftrgo = f / ((psc + 1) * (arr + 1))
 *              波形频率 = ftrgo / ndtr; 
 *
 * @param       ndtr        : DMA通道单次传输数据量
 * @param       arr         : TIM7的自动重装载值
 * @param       psc         : TIM7的分频系数
 * @retval      无
 */
void dac_dma_wave_enable(uint16_t cndtr, uint16_t arr, uint16_t psc)
{
    TIM_HandleTypeDef tim7_handle = {0};
    TIM_MasterConfigTypeDef tim_mater_config = {0};
    
    __HAL_RCC_TIM7_CLK_ENABLE();
    
    tim7_handle.Instance = TIM7;
    tim7_handle.Init.Prescaler = psc;
    tim7_handle.Init.Period = arr;
    HAL_TIM_Base_Init(&tim7_handle);//初始化定时器

    tim_mater_config.MasterOutputTrigger = TIM_TRGO_UPDATE;		//更新事件, 会产生一个TRGO信号
    tim_mater_config.MasterSlaveMode = TIM_MASTERSLAVEMODE_DISABLE;
    HAL_TIMEx_MasterConfigSynchronization(&tim7_handle, &tim_mater_config);

    HAL_TIM_Base_Start(&tim7_handle);

    HAL_DAC_Stop_DMA(&g_dac_dma_handle, DAC_CHANNEL_1);
    HAL_DAC_Start_DMA(&g_dac_dma_handle, DAC_CHANNEL_1, (uint32_t *)g_dac_sin_buf, cndtr, DAC_ALIGN_12B_R);
}