用STM32F407写一个测量100Khz到1MHZ的正弦波频率的代码

要测量100KHz到1MHz范围内的正弦波频率，您可以使用STM32F407的定时器和输入捕获功能。以下是一个示例代码：

#include "stm32f4xx.h"
#include "stm32f4xx_gpio.h"
#include "stm32f4xx_rcc.h"
#include "stm32f4xx_tim.h"

#define TIMER_FREQUENCY 100000000 // 定时器频率 (Hz)

uint32_t captureValue1 = 0;
uint32_t captureValue2 = 0;
uint32_t frequency = 0;

void TIM_Configuration(void);
void GPIO_Configuration(void);

int main(void) {
    GPIO_Configuration();
    TIM_Configuration();

    while (1) {
        // 等待第一个捕获事件
        while (!(TIM_GetFlagStatus(TIM2, TIM_FLAG_CC1) == SET)) {}
        captureValue1 = TIM_GetCapture1(TIM2);

        // 等待第二个捕获事件
        while (!(TIM_GetFlagStatus(TIM2, TIM_FLAG_CC2) == SET)) {}
        captureValue2 = TIM_GetCapture2(TIM2);

        // 计算频率
        if (captureValue2 > captureValue1) {
            frequency = TIMER_FREQUENCY / (captureValue2 - captureValue1);
        } else {
            frequency = 0;
        }

        // 将频率发送到串口或其他操作

        // 清除标志位
        TIM_ClearFlag(TIM2, TIM_FLAG_CC1 | TIM_FLAG_CC2);
    }
}

void TIM_Configuration(void) {
    TIM_ICInitTypeDef  TIM_ICInitStructure;
    NVIC_InitTypeDef NVIC_InitStructure;

    // 使能定时器时钟
    RCC_APB1PeriphClockCmd(RCC_APB1Periph_TIM2, ENABLE);

    // 定时器配置
    TIM_DeInit(TIM2);
    TIM_ICStructInit(&TIM_ICInitStructure);
    TIM_ICInitStructure.TIM_Channel = TIM_Channel_1;
    TIM_ICInitStructure.TIM_ICPolarity = TIM_ICPolarity_Rising;
    TIM_ICInitStructure.TIM_ICSelection = TIM_ICSelection_DirectTI;
    TIM_ICInitStructure.TIM_ICPrescaler = TIM_ICPSC_DIV1;
    TIM_ICInitStructure.TIM_ICFilter = 0x0;
    TIM_PWMIConfig(TIM2, &TIM_ICInitStructure);

    // 配置输入捕获通道2
    TIM_ICInitStructure.TIM_Channel = TIM_Channel_2;
    TIM_PWMIConfig(TIM2, &TIM_ICInitStructure);

    // 配置定时器时钟分频
    TIM_PrescalerConfig(TIM2, 0, 0);

    // 配置定时器自动重装载寄存器
    TIM_SetAutoreload(TIM2, 0xFFFF);

    // 使能定时器输入捕获
    TIM_SelectInputTrigger(TIM2, TIM_TS_TI1FP1);
    TIM_SelectSlaveMode(TIM2, TIM_SlaveMode_Reset);
    TIM_SelectMasterSlaveMode(TIM2, TIM_MasterSlaveMode_Enable);

    // 清除标志位
    TIM_ClearFlag(TIM2, TIM_FLAG_CC1 | TIM_FLAG_CC2);

    // 使能输入捕获中断
    NVIC_InitStructure.NVIC_IRQChannel = TIM2_IRQn;
    NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority = 0;
    NVIC_InitStructure.NVIC_IRQChannelSubPriority = 0;
    NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE;
    NVIC_Init(&NVIC_InitStructure);

    // 使能定时器
    TIM_Cmd(TIM2, ENABLE);
}

void GPIO_Configuration(void) {
    GPIO_InitTypeDef GPIO_InitStructure;

    // 使能GPIO时钟
    RCC_AHB1PeriphClockCmd(RCC_AHB1Periph_GPIOA, ENABLE);

    // 配置GPIO为复用功能
    GPIO_InitStructure.GPIO_Pin = GPIO_Pin_15;
    GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AF;
    GPIO_InitStructure.GPIO_Speed = GPIO_Speed_100MHz;
    GPIO_InitStructure.GPIO_OType = GPIO_OType_PP;
    GPIO_InitStructure.GPIO_PuPd = GPIO_PuPd_NOPULL ;
    GPIO_Init(GPIOA, &GPIO_InitStructure);

    // 配置GPIO引脚复用到定时器
    GPIO_PinAFConfig(GPIOA, GPIO_PinSource15, GPIO_AF_TIM2);
}

void TIM2_IRQHandler(void) {
    if (TIM_GetITStatus(TIM2, TIM_IT_CC1) == SET) {
        TIM_ClearITPendingBit(TIM2, TIM_IT_CC1);
    }

    if (TIM_GetITStatus(TIM2, TIM_IT_CC2) == SET) {
        TIM_ClearITPendingBit(TIM2, TIM_IT_CC2);
    }
}

您可以将频率发送到串口或者其他操作进行进一步处理或显示。此示例代码假设您已经正确配置了系统时钟和其他必要的设置。

请注意，输入捕获的精度受到定时器时钟频率和分频因子的影响，因此可能需要根据实际情况进行适当的调整。

希望对您有所帮助！如果您有任何其他问题，请随时提问。