STM32的扫频绘制幅频特性曲线

对于STM32的扫频绘制幅频特性曲线，你可以使用STM32的定时器和DMA来实现。以下是一个简单的示例代码，供参考：

#include "stm32f4xx.h"

#define SAMPLE_RATE 10000  // 采样率
#define BUFFER_SIZE 5000   // 缓冲区大小

uint16_t adc_buffer[BUFFER_SIZE];  // ADC数据缓冲区

void ADC_Configuration(void)
{
    ADC_InitTypeDef ADC_InitStructure;
    ADC_CommonInitTypeDef ADC_CommonInitStructure;
    GPIO_InitTypeDef GPIO_InitStructure;
    DMA_InitTypeDef DMA_InitStructure;
    
    RCC_APB2PeriphClockCmd(RCC_APB2Periph_ADC1, ENABLE);
    RCC_AHB1PeriphClockCmd(RCC_AHB1Periph_DMA2, ENABLE);
    RCC_AHB1PeriphClockCmd(RCC_AHB1Periph_GPIOA, ENABLE);
    
    // 配置GPIO为模拟输入
    GPIO_InitStructure.GPIO_Pin = GPIO_Pin_0;
    GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AN;
    GPIO_InitStructure.GPIO_PuPd = GPIO_PuPd_NOPULL ;
    GPIO_Init(GPIOA, &GPIO_InitStructure);
    
    // 配置DMA
    DMA_InitStructure.DMA_Channel = DMA_Channel_0;
    DMA_InitStructure.DMA_PeripheralBaseAddr = (uint32_t)&ADC1->DR;
    DMA_InitStructure.DMA_Memory0BaseAddr = (uint32_t)adc_buffer;
    DMA_InitStructure.DMA_DIR = DMA_DIR_PeripheralToMemory;
    DMA_InitStructure.DMA_BufferSize = BUFFER_SIZE;
    DMA_InitStructure.DMA_PeripheralInc = DMA_PeripheralInc_Disable;
    DMA_InitStructure.DMA_MemoryInc = DMA_MemoryInc_Enable;
    DMA_InitStructure.DMA_PeripheralDataSize = DMA_PeripheralDataSize_HalfWord;
    DMA_InitStructure.DMA_MemoryDataSize = DMA_MemoryDataSize_HalfWord;
    DMA_InitStructure.DMA_Mode = DMA_Mode_Circular;
    DMA_InitStructure.DMA_Priority = DMA_Priority_High;
    DMA_InitStructure.DMA_FIFOMode = DMA_FIFOMode_Disable;
    DMA_InitStructure.DMA_FIFOThreshold = DMA_FIFOThreshold_HalfFull;
    DMA_InitStructure.DMA_MemoryBurst = DMA_MemoryBurst_Single;
    DMA_InitStructure.DMA_PeripheralBurst = DMA_PeripheralBurst_Single;
    DMA_Init(DMA2_Stream0, &DMA_InitStructure);
    
    // 配置ADC
    ADC_CommonInitStructure.ADC_Mode = ADC_Mode_Independent;
    ADC_CommonInitStructure.ADC_Prescaler = ADC_Prescaler_Div2;
    ADC_CommonInitStructure.ADC_DMAAccessMode = ADC_DMAAccessMode_1;
    ADC_CommonInitStructure.ADC_TwoSamplingDelay = ADC_TwoSamplingDelay_5Cycles;
    ADC_CommonInit(&ADC_CommonInitStructure);
    
    ADC_InitStructure.ADC_Resolution = ADC_Resolution_12b;
    ADC_InitStructure.ADC_ScanConvMode = DISABLE;
    ADC_InitStructure.ADC_ContinuousConvMode = ENABLE;
    ADC_InitStructure.ADC_ExternalTrigConvEdge = ADC_ExternalTrigConvEdge_None;
    ADC_InitStructure.ADC_DataAlign = ADC_DataAlign_Right;
    ADC_InitStructure.ADC_NbrOfConversion = 1;
    ADC_Init(ADC1, &ADC_InitStructure);
    
    // 配置ADC通道
    ADC_RegularChannelConfig(ADC1, ADC_Channel_0, 1, ADC_SampleTime_3Cycles);
    
    // 使能DMA请求
    ADC_DMARequestAfterLastTransferCmd(ADC1, ENABLE);
    
    // 配置ADC DMA
    ADC_DMACmd(ADC1, ENABLE);
    
    // 启动DMA
    DMA_Cmd(DMA2_Stream0, ENABLE);
    
    // 启动ADC转换
    ADC_Cmd(ADC1, ENABLE);
    
    // 等待ADC稳定
    delay_us(100);
    
    // 启动连续模式转换
    ADC_SoftwareStartConv(ADC1);
}

int main(void)
{
    // 初始化系统时钟等
    
    ADC_Configuration();
    
    while (1)
    {
        // 处理ADC数据，绘制幅频特性曲线
        
        // 延时等待下一次采样
        delay_us(1000000 / SAMPLE_RATE);
    }
}

在上述示例代码中，我们使用了ADC1的通道0来进行采样，并通过DMA2的Stream0将采样数据传输到缓冲区adc_buffer中。然后，你可以根据采样数据进行幅频特性曲线的绘制和处理。注意，示例代码中的delay_us函数需要根据你的实际情况进行实现。

希望这个示例能对你有所帮助！