树莓派读取温湿度传感器DHT11
硬件：树莓派 2.0DHT模块接树莓派5V GND GPIO1 （点此购买）功能：读取传感器数据并打印出来//
//mydht11.c
//
#include <wiringPi.h>
#include <stdio.h>
#include <stdlib.h>
typedef unsigned char uint8;
typedef unsigned intuint16;
typedef unsigned long uint32;
#define HIGH_TIME 32
int pinNumber =1;//use gpio1 to read data
uint32 databuf;
uint8 readSensorData(void)
{
uint8 crc;
uint8 i;
pinMode(pinNumber,OUTPUT); // set mode to output
digitalWrite(pinNumber, 0); // output a high level
delay(25);
digitalWrite(pinNumber, 1); // output a low level
pinMode(pinNumber, INPUT); // set mode to input
pullUpDnControl(pinNumber,PUD_UP);
delayMicroseconds(27);
if(digitalRead(pinNumber)==0) //SENSOR ANS
{
while(!digitalRead(pinNumber)); //wait to high
for(i=0;i<32;i++)
{
while(digitalRead(pinNumber)); //data clock start
while(!digitalRead(pinNumber)); //data start
delayMicroseconds(HIGH_TIME);
databuf*=2;
if(digitalRead(pinNumber)==1) //1
{
databuf++;
}
}
for(i=0;i<8;i++)
{
while(digitalRead(pinNumber)); //data clock start
while(!digitalRead(pinNumber)); //data start
delayMicroseconds(HIGH_TIME);
crc*=2;
if(digitalRead(pinNumber)==1) //1
{
crc++;
}
}
return 1;
}
else
{
return 0;
}
}
int main (void)
{
printf("Use GPIO1 to read data!\n");
if (-1 == wiringPiSetup()) {
printf("Setup wiringPi failed!");
return 1;
}
pinMode(pinNumber, OUTPUT); // set mode to output
digitalWrite(pinNumber, 1); // output a high level
printf("Enter OS-------\n");
while(1) {
pinMode(pinNumber,OUTPUT); // set mode to output
digitalWrite(pinNumber, 1); // output a high level
delay(3000);
if(readSensorData())
{
printf("Congratulations ! Sensor data read ok!\n");
printf("RH:%d.%d\n",(databuf>>24)&0xff,(databuf>>16)&0xff);
printf("TMP:%d.%d\n",(databuf>>8)&0xff,databuf&0xff);
databuf=0;
}
else
{
printf("Sorry! Sensor dosent ans!\n");
databuf=0;
}
}
return 0;
}
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