adc采集会影响串口通讯吗

新手驾到 · 发表于 2016-9-6 11:00:47

本帖最后由新手驾到于 2016-9-6 11:43 编辑

用stm32 A采集两路adc（霍尔摇杆），通过串口传递给另一个stm32 B，然后B借助串口调试工具打印在pc上。当霍尔摇杆不动，采集的adc不变化时候，pc上打印的数据正常，但是拨动摇杆adc采集数据变化时候pc上打印的串口数据就会变动、错位（第一个数据在第二个位置上打印出来，第二个在第三个位置上打印。。）。单独测试过adc采集，不会出现这样的情况，而且打印串口数据出错时候出现延时（单独测试adc不会有），原子哥，各位大神帮忙看看是个什么问题。图中后面两个数据为adc采样的数据24,25,前面两个数据100,2放着用于对比

代码都是用历程中的，然后修改对应的管脚等参数
以下是adc采集发送的代码：
int main(void)
{
            float adcx1,adcx2;
            u8 flag=100,speed=2;
            delay_init();
            NVIC_Configuration();
               LED_Init();
            uart1_init(9600);
            Adc_Init();

      while(1)
      {
               adcx1=Get_Adc_Average(ADC_Channel_6,10)*50/4096.0;
               adcx2=Get_Adc_Average(ADC_Channel_7,10)*50/4096.0;

  //                   printf("***%f %f \r\n",adcx1,adcx2);
                     delay_ms(5);                USART_SendData(USART1,flag);
                     delay_ms(5);
               USART_SendData(USART1,speed);
                     delay_ms(5);
               USART_SendData(USART1,adcx1);
               delay_ms(5);
               USART_SendData(USART1,adcx2);

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void  Adc_Init(void)
{
      ADC_InitTypeDef ADC_InitStructure;
      GPIO_InitTypeDef GPIO_InitStructure;
      RCC_APB2PeriphClockCmd(RCC_APB2Periph_GPIOA|RCC_APB2Periph_GPIOB  |RCC_APB2Periph_ADC1, ENABLE );       //adc1时钟使能
      RCC_ADCCLKConfig(RCC_PCLK2_Div6); //设置分频
      //PA6,PA7设置为模拟通道
      GPIO_InitStructure.GPIO_Pin = GPIO_Pin_6|GPIO_Pin_7;
      GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AIN;
      GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;
      GPIO_Init(GPIOA, &GPIO_InitStructure);
      GPIO_InitStructure.GPIO_Pin = GPIO_Pin_0;
      GPIO_Init(GPIOB, &GPIO_InitStructure);

      ADC_DeInit(ADC1);

      ADC_InitStructure.ADC_Mode = ADC_Mode_Independent;
      ADC_InitStructure.ADC_ScanConvMode = DISABLE;
      ADC_InitStructure.ADC_ContinuousConvMode = DISABLE;
      ADC_InitStructure.ADC_ExternalTrigConv = ADC_ExternalTrigConv_None;
      ADC_InitStructure.ADC_DataAlign = ADC_DataAlign_Right;
      ADC_InitStructure.ADC_NbrOfChannel = 1;
      ADC_Init(ADC1, &ADC_InitStructure);

      ADC_Cmd(ADC1, ENABLE);
      ADC_ResetCalibration(ADC1);
      while(ADC_GetResetCalibrationStatus(ADC1));
      ADC_StartCalibration(ADC1);
      while(ADC_GetCalibrationStatus(ADC1));
}

u16 Get_Adc(u8 ch)
{
      ADC_RegularChannelConfig(ADC1, ch, 1, ADC_SampleTime_239Cycles5 );
      ADC_SoftwareStartConvCmd(ADC1, ENABLE);
      while(!ADC_GetFlagStatus(ADC1, ADC_FLAG_EOC ));
      return ADC_GetConversionValue(ADC1);
}

u16 Get_Adc_Average(u8 ch,u8 times)
{
      u32 temp_val=0;
      u8 t;
      for(t=0;t<times;t++)
      {
            temp_val+=Get_Adc(ch);
      //       delay_ms(5);
      }
      return temp_val/times;
}

void uart1_init(u32 bound){
            GPIO_InitTypeDef GPIO_InitStructure;
            USART_InitTypeDef USART_InitStructure;
            NVIC_InitTypeDef NVIC_InitStructure;
            RCC_APB2PeriphClockCmd(RCC_APB2Periph_USART1, ENABLE);
            RCC_APB2PeriphClockCmd(RCC_APB2Periph_GPIOA, ENABLE);
            USART_DeInit(USART1);
      //USART2_TX PA.9
GPIO_InitStructure.GPIO_Pin = GPIO_Pin_9; //PA.9
GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;
GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AF_PP;
GPIO_Init(GPIOA, &GPIO_InitStructure);
   //USART2_RX       PA.10
GPIO_InitStructure.GPIO_Pin = GPIO_Pin_10;
GPIO_InitStructure.GPIO_Mode = GPIO_Mode_IN_FLOATING;
GPIO_Init(GPIOA, &GPIO_InitStructure);
NVIC_InitStructure.NVIC_IRQChannel = USART1_IRQn;
            NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority=2 ;
            NVIC_InitStructure.NVIC_IRQChannelSubPriority = 4;
            NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE;
            NVIC_Init(&NVIC_InitStructure);

            USART_InitStructure.USART_BaudRate = bound;
            USART_InitStructure.USART_WordLength = USART_WordLength_8b;
            USART_InitStructure.USART_StopBits = USART_StopBits_1;
            USART_InitStructure.USART_Parity = USART_Parity_No;
            USART_InitStructure.USART_HardwareFlowControl = USART_HardwareFlowControl_None;
            USART_InitStructure.USART_Mode = USART_Mode_Rx | USART_Mode_Tx;

USART_Init(USART1, &USART_InitStructure);
USART_ITConfig(USART1, USART_IT_RXNE, ENABLE);
USART_Cmd(USART1, ENABLE);
}

个人觉得应该是时序的问题，
USART_SendData(USART1,flag);
delay_ms(5);
在发送数据时候设定不同的延时时间5ms，8ms，会出现不同的数据错位情况。