dht22代码stm32
时间: 2024-05-14 13:10:21 浏览: 106
DHT22是一种数字温湿度传感器,可以通过单片机读取温度和湿度数据。下面是一个基于STM32的DHT22驱动代码示例:
```
#include "dht22.h"
#include "delay.h"
#define DHT22_DATA_OUT GPIOA->ODR &= ~(1 << 1)
#define DHT22_DATA_IN GPIOA->IDR & (1 << 1)
#define DHT22_DATA_HIGH GPIOA->ODR |= (1 << 1)
#define DHT22_DATA_LOW GPIOA->ODR &= ~(1 << 1)
void DHT22_Start(void)
{
DHT22_DATA_LOW;
delay_ms(18);
DHT22_DATA_HIGH;
delay_us(30);
while(DHT22_DATA_IN);
while(!DHT22_DATA_IN);
}
uint8_t DHT22_Read_Byte(void)
{
uint8_t i, j, k;
uint8_t res = 0;
for (i = 0; i < 8; i++) {
j = 0;
while(!DHT22_DATA_IN) {
j++;
if (j > 200) return 0;
delay_us(1);
}
delay_us(40);
k = 0;
if (DHT22_DATA_IN) k = 1;
res = (res << 1) | k;
j = 0;
while(DHT22_DATA_IN) {
j++;
if (j > 200) return 0;
delay_us(1);
}
}
return res;
}
void DHT22_Read_Data(int16_t *temp, int16_t *humi)
{
uint8_t buf;
uint8_t i;
*temp = *humi = 0;
DHT22_Start();
if (DHT22_DATA_IN) return;
delay_us(80);
if (!DHT22_DATA_IN) return;
delay_us(80);
for (i = 0; i < 5; i++) {
buf[i] = DHT22_Read_Byte();
}
if ((buf + buf + buf + buf) != buf) return;
*humi = (buf << 8) | buf;
*temp = (buf << 8) | buf;
}
```
以上代码中,需要自行实现延时函数(delay_ms()和delay_us())。此外,需要在MCU上配置相应的GPIO引脚来连接DHT22传感器。