stm32f103使用DAC输出固定电压，DAC管脚无输出

只看该作者 · 2017-2-8 16:08

采用stm32 DAC1通道输出固定电压，但测量PA4管脚无电压输出

只看该作者 · 2017-2-8 16:09

GPIO_InitTypeDef  GPIO_InitStructure;
DAC_InitTypeDef  DAC_InitStructure;
// DMA_InitTypeDef DMA_InitStructure;
//启动GPIOA
RCC_APB2PeriphClockCmd(RCC_APB2Periph_GPIOA, ENABLE);
//启动DAC1时钟
RCC_APB2PeriphClockCmd(RCC_APB1Periph_DAC, ENABLE);
//dac采用pa4管脚输出
GPIO_InitStructure.GPIO_Pin =  GPIO_Pin_4;
GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AIN;
GPIO_InitStructure.GPIO_Speed=GPIO_Speed_50MHz;
GPIO_Init(GPIOA, &GPIO_InitStructure);

DAC_InitStructure.DAC_Trigger = DAC_Trigger_None;//DAC_Trigger_T2_TRGO;
DAC_InitStructure.DAC_WaveGeneration = DAC_WaveGeneration_None;
DAC_InitStructure.DAC_LFSRUnmask_TriangleAmplitude = DAC_TriangleAmplitude_4095;
DAC_InitStructure.DAC_OutputBuffer = DAC_OutputBuffer_Enable;//使能DAC通道缓存
DAC_Init(DAC_Channel_1, &DAC_InitStructure);
DAC_Cmd(DAC_Channel_1, ENABLE);
DAC_SoftwareTriggerCmd(DAC_Channel_1,ENABLE);

      DAC_SetChannel1Data(DAC_Align_12b_R,2000);//12位右对齐,输出0
DAC_SoftwareTriggerCmd(DAC_Channel_1,ENABLE);

只看该作者 · 2017-2-8 16:10

网上的例程也基本都是这样，问什么会没有输出呢

只看该作者 · 2017-2-8 16:33

      GPIO_InitTypeDef  GPIO_InitStructure;
      DAC_InitTypeDef  DAC_InitStructure;
//       DMA_InitTypeDef DMA_InitStructure;
      //启动GPIOA
      RCC_APB2PeriphClockCmd(RCC_APB2Periph_GPIOA, ENABLE);
      //启动DAC1时钟
      RCC_APB2PeriphClockCmd(RCC_APB1Periph_DAC, ENABLE);

看到问题了吗？不仔细的话很容易出错