atmega128 dht11 코드 + 코드 작성 위한 아두이노 라이브러리 찾기

main.c

/*
 * dht11.c
 *
 * Created: 2021-02-04 오전 10:30:42
 * Author : User
 */ 
#define F_CPU 16000000UL
#include <avr/io.h>
#include <util/delay.h>
#include "dht11.h"

int main(void)
{
	initDHT11(DDRB, PORTB, PINB, PB7);
   
	while (1) 
	{
		int err;
		float temp, humi;
		if((err = read(&humi, &temp))==0)
		{
			Serial.print("temperature:");
			Serial.print(temp);
			Serial.print(" humidity:");
			Serial.print(humi);
			Serial.println();
		}
		else
		{
			Serial.println();
			Serial.print("Error No :");
			Serial.print(err);
			Serial.println();
		}
		//delay(DHT11_RETRY_DELAY); //delay for reread
	}
}

dht11.h

/*
 * dht11.h
 *
 * Created: 2021-02-04 오전 11:18:57
 *  Author: User
 */ 


#ifndef DHT11_H_
#define DHT11_H_


#define HIGH	1
#define LOW		0
#define DHT11_RETRY_DELAY 1000 //1000ms

typedef unsigned char uint8_t;
typedef unsigned long uint32_t;

//전역변수화 시킴 g_(global 변수를 의미)
int g_pin;  
unsigned long last_read_time;
int g_input; //PINx & (1<<PINxn)
int g_direction; //DDRx
int g_port;

//함수 prototype
unsigned char readByte();
unsigned long waitFor2(uint8_t target, uint32_t time_out_us);
void waitFor1(uint8_t target);
int read(float* humidity, float* temperature);
void initDHT11(int direction, int port, int input, int pin_number);
unsigned long millis();
unsigned long micros();

#endif /* DHT11_H_ */

dht11.c

/*
 * dht11.c
 *
 * Created: 2021-02-04 오전 11:20:41
 *  Author: User
 */ 

#define F_CPU 16000000UL
#include <avr/io.h>
#include <util/delay.h>
#include "dht11.h"

void initDHT11(int direction, int port, int input, int pin_number){
	g_pin = pin_number;
	g_direction = direction;
	g_port = port;
	g_input = input;
	last_read_time=0;
	g_direction |= 0 << pin_number;
	g_port |= 1 << pin_number;	
	
}

//wait for target status
//parameters
//  target : target status waiting for
//  time_out_us : time out in microsecond.
uint32_t waitFor2(uint8_t target, uint32_t time_out_us) {
	uint32_t start = micros();
	uint32_t time_out = start+time_out_us;
	
	while((g_input & (1 << g_pin)) !=target)
	{
		if(time_out < micros()) return -1;
	}
	return micros()-start;
}

//wait for target status.
void waitFor1(uint8_t target) {
	while((g_input & (1 << g_pin)) !=target);
}

//read one bye
uint8_t readByte() {
	int i=0;
	uint8_t ret = 0;
	for(i=7;i>=0;i--)
	{
		waitFor1(HIGH); //wait for 50us in LOW status
		_delay_us(30); //wait for 30us
		if((g_input & (1 << g_pin))==HIGH) //if HIGH status lasts for 30us, the bit is 1;
		{
			ret|=1<<(i);
			waitFor1(LOW); //wait for rest time in HIGH status.
		}
	}
	return ret;
}

int read (float* humidity, float* temperature) {
	if((millis() - last_read_time < DHT11_RETRY_DELAY) && last_read_time !=0)	{ 
		return -1;
	}

	
	g_direction |= 1 << g_pin;
	g_port |= 0 << g_pin;
	_delay_ms(18);
	g_port |= 1 << g_pin;
	g_direction |= 0 << g_pin;

	if(waitFor2(LOW, 40)<0)	return 1; //waiting for DH11 ready
	if(waitFor2(HIGH, 90)<0) return 1; //waiting for first LOW signal(80us)
	if(waitFor2(LOW, 90)<0)	return 1; //waiting for first HIGH signal(80us)

	uint8_t hI = readByte();
	uint8_t hF = readByte();
	uint8_t tI = readByte();
	uint8_t tF = readByte();
	uint8_t cksum = readByte();
	if(hI + hF + tI + tF != cksum){
		return 4;
	}
	
	*humidity = (float)hI+(((float)hF)/100.0F);
	*temperature = (float)tI+(((float)tF)/100.0F);
	last_read_time = millis();
	return 0;
}

unsigned long micros() {
	return 0;
}

unsigned long millis(){
	return 0;
}

 

#include "" 로 쓰는것과 #include <> 의 차이

""는 내가 만든 헤더파일. 같은 경로에 있음

<>는 이미 선언 되어있는 ? 것

<> 를 먼저 쓰고

""를 쓰는것이 원칙이긴 하다

---

.c 안에는 헤더파일 여러개 넣어도 충돌위험을 크게 걱정하지 않아도 된다 ..

.h 안에는 헤더파일 여러개 넣을 때 충돌을 주의하여야 한다

---

dht11 아두이노 라이브러리 

DHT11.h

/*
 * DH11.h
 *
 *  Created on: 2012. 12. 12.
 *      Author: dalxx
 *      Version : 0.8
 */

#ifndef DHT11_H_
#define DHT11_H_
#include <Arduino.h>
#define DHT11_RETRY_DELAY 1000  // 1000ms

class DHT11 {
	int pin;
	unsigned long last_read_time;

protected:
	byte readByte();
	unsigned long waitFor(uint8_t target, unsigned long time_out_us);
	void waitFor(uint8_t target);

public:
	DHT11(int pin_number);
	~DHT11();
	int read( float& humidity, float& temperature);
};

#endif /* DHT11_H_ */

unsigned long waitFor(uint8_t target, unsigned long time_out_us);
void waitFor(uint8_t target);

c언어에서는 똑같은 함수 두번 선언하면 오류남
객체지향에서는 가능 : 함수 오버로딩 이라고 함

DHT11.cpp

/*
 * DH11.cpp
 *
 *  Created on: 2012. 12. 12.
 *      Author: dalxx
 */

#include "DHT11.h"
#include <Arduino.h>

DHT11::DHT11(int pin_number) {
	pin=pin_number;
	this->last_read_time=0;
	pinMode(pin,INPUT);
	digitalWrite(pin, HIGH);

}
//wait for target status
//parameters
//  target : target status waiting for
//  time_out_us : time out in microsecond.
unsigned long DHT11::waitFor(uint8_t target, unsigned long time_out_us) {
	unsigned long start=micros();
	unsigned long time_out=start+time_out_us;
	while(digitalRead(this->pin)!=target)
	{
		if(time_out<micros()) return -1;
	}
	return micros()-start;
}

//wait for target status.
void DHT11::waitFor(uint8_t target) {
	while(digitalRead(this->pin)!=target);
}

//read one bye
byte DHT11::readByte() {
	int i=0;
	byte ret=0;
	for(i=7;i>=0;i--)
	{
		waitFor(HIGH); //wait for 50us in LOW status
		delayMicroseconds(30); //wait for 30us
		if(digitalRead(this->pin)==HIGH) //if HIGH status lasts for 30us, the bit is 1;
		{
			ret|=1<<(i);
			waitFor(LOW); //wait for rest time in HIGH status.
		}
	}
	return ret;
}

DHT11::~DHT11() {
	// TODO Auto-generated destructor stub
}
//parameters
//	temperature : temperature to read.
//	humidity : humidity to read.
//return -1 : read too shortly. retry latter .
//		  0 : read successfully
//        1 : DHT11 not ready.
//		  4 : Checksum Error
int DHT11::read(float& humidity, float& temperature) {
	if((millis()-this->last_read_time<DHT11_RETRY_DELAY)&&this->last_read_time!=0)	return -1;

	pinMode(pin,OUTPUT);
	digitalWrite(pin, LOW);
	delay(18);
	digitalWrite(pin, HIGH);
	pinMode(pin,INPUT);

	if(waitFor(LOW, 40)<0)	return 1; //waiting for DH11 ready
	if(waitFor(HIGH, 90)<0)	return 1; //waiting for first LOW signal(80us)
	if(waitFor(LOW, 90)<0)	return 1; //waiting for first HIGH signal(80us)

	byte hI=this->readByte();
	byte hF=this->readByte();
	byte tI=this->readByte();
	byte tF=this->readByte();
	byte cksum=this->readByte();
	if(hI+hF+tI+tF!=cksum)
		return 4;


	humidity=(float)hI+(((float)hF)/100.0F);
	temperature=(float)tI+(((float)tF)/100.0F);
	this->last_read_time=millis();
	return 0;
}

 

DHT11-Technical-Data-Sheet-Translated-Version-1143054.pdf

1.42MB

 

 

 

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참고

DHT11_Datasheet_Aosong.pdf

1.02MB

 

 

DHT11-Temperature-Sensor.pdf

0.65MB