关于用定时器触发ADC采集外部电压的问题，请看一下我的问题

wang呆呆 · 发表于 2016-6-3 11:54:21

//time2初始化
void Tim2Config(void)
{
TIM_TimeBaseInitTypeDef TIM_TimeBaseInitStruct;
//´开时钟
RCC_APB1PeriphClockCmd(RCC_APB1Periph_TIM2,ENABLE);

TIM_TimeBaseInitStruct.TIM_ClockDivision=TIM_CKD_DIV1;
TIM_TimeBaseInitStruct.TIM_Prescaler=42-1;
TIM_TimeBaseInitStruct.TIM_Period=44;
TIM_TimeBaseInitStruct.TIM_CounterMode=TIM_CounterMode_Up;
TIM_TimeBaseInit(TIM2,&TIM_TimeBaseInitStruct);
//选择输出触发方式，这里选择了数据更新触发
TIM_SelectOutputTrigger(TIM2,TIM_TRGOSource_Update);
TIM_Cmd(TIM2,ENABLE); //使能
}
//初始化ADC
void Adc_Init(void)
{
GPIO_InitTypeDef GPIO_InitStruct;
ADC_CommonInitTypeDef ADC_CommonInitStruct;
ADC_InitTypeDef ADC_InitStruct;

RCC_AHB1PeriphClockCmd(RCC_AHB1Periph_GPIOA,ENABLE); //
  RCC_APB2PeriphClockCmd(RCC_APB2Periph_ADC1,ENABLE);  //

GPIO_InitStruct.GPIO_Pin=GPIO_Pin_5;
GPIO_InitStruct.GPIO_Mode=GPIO_Mode_AN;
GPIO_InitStruct.GPIO_PuPd=GPIO_PuPd_NOPULL;
GPIO_Init(GPIOA,&GPIO_InitStruct);

RCC_APB2PeriphResetCmd(RCC_APB2Periph_ADC1,ENABLE);
RCC_APB2PeriphResetCmd(RCC_APB2Periph_ADC1,DISABLE);

ADC_CommonInitStruct.ADC_Mode=ADC_Mode_Independent;
ADC_CommonInitStruct.ADC_TwoSamplingDelay=ADC_TwoSamplingDelay_5Cycles
ADC_CommonInitStruct.ADC_DMAAccessMode=ADC_DMAAccessMode_Disabled;
ADC_CommonInitStruct.ADC_Prescaler=ADC_Prescaler_Div4;
ADC_CommonInit(&ADC_CommonInitStruct);


ADC_InitStruct.ADC_Resolution=ADC_Resolution_12b;
ADC_InitStruct.ADC_ScanConvMode=DISABLE;
ADC_InitStruct.ADC_ContinuousConvMode=DISABLE;
ADC_InitStruct.ADC_ExternalTrigConvEdge=ADC_ExternalTrigConvEdge_Rising;
ADC_InitStruct.ADC_ExternalTrigConv=ADC_ExternalTrigConv_T2_TRGO
ADC_InitStruct.ADC_NbrOfConversion=1;
ADC_Init(ADC1,&ADC_InitStruct);

ADC_Cmd(ADC1,ENABLE);
}

u16 Get_Adc(u8 ch)
{

ADC_RegularChannelConfig(ADC1,ch,1,ADC_SampleTime_480Cycles); //µÚÈý¸ö²ÎÊýÎª¹æÔò×é²ÉÑùµÚÒ»¸ö
//ADC_SoftwareStartConv(ADC1);//Ê¹ÄÜÖ¸¶¨µÄADC1µÄÈí¼þ×ª»»Æô¶¯¹¦ÄÜ
ADC_ExternalTrigInjectedConvConfig(ADC1,ADC_ExternalTrigInjecConv_T2_TRGO);
ADC_ExternalTrigInjectedConvEdgeConfig(ADC1,ADC_ExternalTrigInjecConvEdge_Rising);

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;
}

大家帮忙看一下问题在哪里，定时器触发ADC采集，现在采集不到电压。

wang呆呆 · 发表于 2016-6-3 11:54:22

已解决，将u16 Get_Adc(u8 ch)
{

ADC_RegularChannelConfig(ADC1,ch,1,ADC_SampleTime_480Cycles);
while(!ADC_GetFlagStatus(ADC1,ADC_FLAG_EOC));
return ADC_GetConversionValue(ADC1);
} 这样写就可以了只需要把ADC规则通道配置一下就好了，直接可以采集到数据了