stm32超声波测距温度补偿计算

根据提供的引用内容，超声波测距需要进行温度补偿计算，以下是一个基于STM32的超声波测距温度补偿计算的示例代码：

#include "stm32f10x.h"
#include "delay.h"
#include "usart.h"

#define TRIG_PORT GPIOA
#define TRIG_PIN GPIO_Pin_0
#define ECHO_PORT GPIOA
#define ECHO_PIN GPIO_Pin_1

void HCSR04_Init(void)
{
    GPIO_InitTypeDef GPIO_InitStructure;

    RCC_APB2PeriphClockCmd(RCC_APB2Periph_GPIOA, ENABLE);

    GPIO_InitStructure.GPIO_Pin = TRIG_PIN;
    GPIO_InitStructure.GPIO_Mode = GPIO_Mode_Out_PP;
    GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;
    GPIO_Init(TRIG_PORT, &GPIO_InitStructure);

    GPIO_InitStructure.GPIO_Pin = ECHO_PIN;
    GPIO_InitStructure.GPIO_Mode = GPIO_Mode_IPU;
    GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;
    GPIO_Init(ECHO_PORT, &GPIO_InitStructure);
}

float HCSR04_GetDistance(void)
{
    uint32_t start_time = 0, end_time = 0;
    float distance = 0;
    uint8_t retry = 0;

    TRIG_PORT->BSRR = TRIG_PIN << 16;
    delay_us(2);
    TRIG_PORT->BSRR = TRIG_PIN;

    while ((ECHO_PORT->IDR & ECHO_PIN) == 0 && retry < 200)
    {
        delay_us(10);
        retry++;
    }

    if (retry >= 200)
    {
        return -1;
    }

    start_time = TIM2->CNT;

    retry = 0;
    while ((ECHO_PORT->IDR & ECHO_PIN) != 0 && retry < 500)
    {
        delay_us(10);
        retry++;
    }

    if (retry >= 500)
    {
        return -1;
    }

    end_time = TIM2->CNT;

    distance = (float)(end_time - start_time) * 0.01715f;

    return distance;
}

float HCSR04_GetDistanceWithTempCompensation(float temperature)
{
    float distance = 0;
    float speed_of_sound = 331.5f + 0.6f * temperature;
    distance = HCSR04_GetDistance() * (speed_of_sound / 10000.0f);
    return distance;
}

该代码使用了STM32的定时器来计算超声波的回波时间，从而计算出距离。在`HCSR04_GetDistanceWithTempCompensation`函数中，根据提供的温度值计算出声速，然后使用声速对距离进行修正，从而实现了温度补偿计算。