STM32ADC注入通道的使用

通过ADC注入通道的使用，可以实时获取4个GPIO输入的AD采样值，下面看具体的代码。
芯片：STM32F205VCT6

STEP1：初始化GPIO

void GPIO_Configuration ( void )
{
//GPIO -PC0 PC1 PC2 PC3 -ADC3
    GPIO_InitStructure.GPIO_Pin     = GPIO_Pin_0 | GPIO_Pin_1 | GPIO_Pin_2 | GPIO_Pin_3;
    GPIO_InitStructure.GPIO_Mode    = GPIO_Mode_AN;
    GPIO_InitStructure.GPIO_PuPd    = GPIO_PuPd_NOPULL;
    GPIO_InitStructure.GPIO_Speed   = GPIO_Speed_50MHz;
    GPIO_Init ( GPIOC, &GPIO_InitStructure );
}

STEP2:初始化ADC

void ADC_Configuration(void)
{                                       
    ADC_InitTypeDef       ADC_InitStructure;
    ADC_CommonInitTypeDef ADC_CommonInitStructure;

    RCC_APB2PeriphClockCmd(RCC_APB2Periph_ADC3, ENABLE);

//ADC Common Init 
    ADC_CommonInitStructure.ADC_Mode                = ADC_Mode_Independent;
    ADC_CommonInitStructure.ADC_Prescaler           = ADC_Prescaler_Div4;
    ADC_CommonInitStructure.ADC_DMAAccessMode       = ADC_DMAAccessMode_Disabled;
    ADC_CommonInitStructure.ADC_TwoSamplingDelay    = ADC_TwoSamplingDelay_20Cycles;
    ADC_CommonInit(&ADC_CommonInitStructure);

// ADC3 Init 
    ADC_InitStructure.ADC_Resolution                = ADC_Resolution_12b;
    ADC_InitStructure.ADC_ScanCOnvMode= ENABLE;
    ADC_InitStructure.ADC_COntinuousConvMode= ENABLE;
    ADC_InitStructure.ADC_ExternalTrigCOnvEdge= ADC_ExternalTrigConvEdge_None;
    ADC_InitStructure.ADC_ExternalTrigCOnv= ADC_ExternalTrigConv_T1_CC1;
    ADC_InitStructure.ADC_DataAlign                 = ADC_DataAlign_Right;
    ADC_InitStructure.ADC_NbrOfCOnversion= 1;
    ADC_Init(ADC3, &ADC_InitStructure);

    ADC_TempSensorVrefintCmd(ENABLE);
    ADC_RegularChannelConfig(ADC3, ADC_Channel_Vrefint, 1, ADC_SampleTime_144Cycles);

    ADC_AutoInjectedConvCmd(ADC3, ENABLE);
    ADC_ExternalTrigInjectedConvEdgeConfig(ADC3, ADC_ExternalTrigInjecConvEdge_None); 
    ADC_InjectedSequencerLengthConfig(ADC3, 4);
    ADC_InjectedChannelConfig(ADC3, ADC_Channel_10, 3,ADC_SampleTime_144Cycles);
    ADC_InjectedChannelConfig(ADC3, ADC_Channel_11, 4,ADC_SampleTime_144Cycles);
    ADC_InjectedChannelConfig(ADC3, ADC_Channel_12, 2,ADC_SampleTime_144Cycles);
    ADC_InjectedChannelConfig(ADC3, ADC_Channel_13, 1,ADC_SampleTime_144Cycles);
    ADC_SetInjectedOffset(ADC3, ADC_InjectedChannel_1, 2000);//采样后的值减去阈值，可以省去后续的处理
    ADC_SetInjectedOffset(ADC3, ADC_InjectedChannel_2, 2000);

// Enable ADC3 
    ADC_Cmd(ADC3, ENABLE);
    ADC_SoftwareStartConv(ADC3);
}

STEP3：使用

value1 = ADC_GetInjectedConversionValue(ADC3, ADC_InjectedChannel_1);
value2 = ADC_GetInjectedConversionValue(ADC3, ADC_InjectedChannel_2);
value3 = ADC_GetInjectedConversionValue(ADC3, ADC_InjectedChannel_3);
value4 = ADC_GetInjectedConversionValue(ADC3, ADC_InjectedChannel_4);