用stm32驱动dht11

以下是使用STM32驱动DHT11的示例代码：

#include "stm32f10x.h"

#define DHT11_PIN   GPIO_Pin_0
#define DHT11_PORT  GPIOA

#define DHT11_TIMEOUT 10000

void delay_us(uint32_t us) {
    uint32_t count = us * (SystemCoreClock / 1000000) / 5;
    while (count--);
}

void DHT11_Start(void) {
    GPIO_InitTypeDef GPIO_InitStructure;
    GPIO_InitStructure.GPIO_Pin = DHT11_PIN;
    GPIO_InitStructure.GPIO_Mode = GPIO_Mode_Out_PP;
    GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;
    GPIO_Init(DHT11_PORT, &GPIO_InitStructure);
    GPIO_SetBits(DHT11_PORT, DHT11_PIN);
    delay_us(1000);
    GPIO_ResetBits(DHT11_PORT, DHT11_PIN);
    delay_us(18000);
    GPIO_SetBits(DHT11_PORT, DHT11_PIN);
    delay_us(30);
}

uint8_t DHT11_Check_Response(void) {
    uint8_t count = 0;
    GPIO_InitTypeDef GPIO_InitStructure;
    GPIO_InitStructure.GPIO_Pin = DHT11_PIN;
    GPIO_InitStructure.GPIO_Mode = GPIO_Mode_IN_FLOATING;
    GPIO_Init(DHT11_PORT, &GPIO_InitStructure);
    while (GPIO_ReadInputDataBit(DHT11_PORT, DHT11_PIN) == SET) {
        count++;
        if (count > DHT11_TIMEOUT)
            return 1;
        delay_us(1);
    }
    count = 0;
    while (GPIO_ReadInputDataBit(DHT11_PORT, DHT11_PIN) == RESET) {
        count++;
        if (count > DHT11_TIMEOUT)
            return 1;
        delay_us(1);
    }
    count = 0;
    while (GPIO_ReadInputDataBit(DHT11_PORT, DHT11_PIN) == SET) {
        count++;
        if (count > DHT11_TIMEOUT)
            return 1;
        delay_us(1);
    }
    return 0;
}

uint8_t DHT11_Read_Bit(void) {
    uint8_t count = 0;
    while (GPIO_ReadInputDataBit(DHT11_PORT, DHT11_PIN) == RESET) {
        count++;
        if (count > DHT11_TIMEOUT)
            return 1;
        delay_us(1);
    }
    delay_us(40);
    if (GPIO_ReadInputDataBit(DHT11_PORT, DHT11_PIN) == SET)
        return 1;
    else
        return 0;
}

uint8_t DHT11_Read_Byte(void) {
    uint8_t i, data = 0;
    for (i = 0; i < 8; i++) {
        data <<= 1;
        if (DHT11_Read_Bit())
            data |= 1;
    }
    return data;
}

uint8_t DHT11_Read_Data(uint8_t *humidity, uint8_t *temperature) {
    uint8_t i, data[5];
    DHT11_Start();
    if (DHT11_Check_Response()) {
        return 1;
    }
    for (i = 0; i < 5; i++) {
        data[i] = DHT11_Read_Byte();
    }
    *humidity = data[0];
    *temperature = data[2];
    return 0;
}

int main(void) {
    uint8_t humidity, temperature;
    RCC_APB2PeriphClockCmd(RCC_APB2Periph_GPIOA, ENABLE);
    while (1) {
        if (DHT11_Read_Data(&humidity, &temperature) == 0) {
            //读取到温湿度数据，进行处理
        }
        delay_us(2000000);
    }
}