stm32f407adc读取电压

读取电压需要使用ADC(Analog-to-Digital Converter)模块。下面是一个简单的代码示例，可以读取ADC通道的电压并将其转换为实际电压值。

/* 定义ADC通道和GPIO引脚 */
#define ADC_PORT GPIOA
#define ADC_PIN GPIO_Pin_0
#define ADC_CHANNEL ADC_Channel_0

/* 初始化ADC */
void ADC_Init(void)
{
    ADC_InitTypeDef ADC_InitStruct;
    GPIO_InitTypeDef GPIO_InitStruct;
 
    RCC_APB2PeriphClockCmd(RCC_APB2Periph_ADC1, ENABLE);
    RCC_AHB1PeriphClockCmd(RCC_AHB1Periph_GPIOA, ENABLE);
 
    GPIO_InitStruct.GPIO_Pin = ADC_PIN;
    GPIO_InitStruct.GPIO_Mode = GPIO_Mode_AN;
    GPIO_InitStruct.GPIO_PuPd = GPIO_PuPd_NOPULL;
    GPIO_Init(ADC_PORT, &GPIO_InitStruct);
 
    ADC_DeInit();
    ADC_InitStruct.ADC_Resolution = ADC_Resolution_12b;
    ADC_InitStruct.ADC_ScanConvMode = DISABLE;
    ADC_InitStruct.ADC_ContinuousConvMode = DISABLE;
    ADC_InitStruct.ADC_ExternalTrigConvEdge = ADC_ExternalTrigConvEdge_None;
    ADC_InitStruct.ADC_DataAlign = ADC_DataAlign_Right;
    ADC_InitStruct.ADC_NbrOfConversion = 1;
    ADC_Init(ADC1, &ADC_InitStruct);
 
    ADC_Cmd(ADC1, ENABLE);
}

/* 读取ADC通道的电压值 */
float ADC_ReadVoltage(void)
{
    uint16_t adc_value;
    float voltage;
 
    ADC_RegularChannelConfig(ADC1, ADC_CHANNEL, 1, ADC_SampleTime_3Cycles);
    ADC_SoftwareStartConv(ADC1);
 
    while(ADC_GetFlagStatus(ADC1, ADC_FLAG_EOC) == RESET);
    adc_value = ADC_GetConversionValue(ADC1);
 
    voltage = (float)adc_value / 4095 * 3.3; // 3.3V为模拟电压参考电压
    return voltage;
}

需要注意的是，ADC的精度和参考电压需要根据具体的硬件环境进行调整。