STM32 DHT11 온습도센서

Timer11 Period = 65535로 설정

사용할 핀 정의

 

 

DHT11.c

#include "main.h"
#include "DHT11.h"

#include <stdio.h>
#include <string.h>
#include <stdlib.h>

// extern TIM_HandleTypeDef htim2;
extern void delay_us (unsigned long us);
extern volatile int TDHT11_timer_counter;
extern volatile int TIM11_10ms_counter;
void DHT11_main(void);

void DHT11_main(void)
{
	uint8_t i_RH, d_RH, i_Tmp, d_Tmp;
	
	// HAL_TIM_Base_Start_IT(&htim2);
	DHT11_Init();
	
	while(1)
	{
		DHT11_trriger();
		DHT11_DataLine_Input();
		DHT11_dumi_read();
		
		i_RH = DHT11_rx_Data();
		d_RH = DHT11_rx_Data();
		i_Tmp = DHT11_rx_Data();
		d_Tmp = DHT11_rx_Data();
		
		DHT11_DataLine_Output();
		HAL_GPIO_WritePin(DHT11_PORT, DHT11_DATA_RIN, GPIO_PIN_SET);
		printf("[Tmp]%d\n",(int)i_Tmp);
		printf("[Wet]%d\n",(int)i_RH);
		// FND_Update(i_Tmp*100 + i_RH);
		HAL_Delay(1500);
	}
	
}

int dht11on=1;   //dht11on : 1 DHT11_processing를 실행 하고 dht11on: 0 return
int dht11time=150;   // pc 로 부터 dht11 check time을 읽어서 ascii to int 저장하는 변수
void DHT11_processing(void)
{
	uint8_t i_RH, d_RH, i_Tmp, d_Tmp;
    //
	// dht11time1500   : 1500ms
	// dht11time2000   : 2000ms
	// dht11time3000   : 3000ms
	// dht11timeaa12   : 잘못 입력 기본 check : 1500

	if (!dht11on) return;

	if (TIM11_10ms_counter >= dht11time) // 1500ms ~ 3000ms
	{
		TIM11_10ms_counter=0;
		DHT11_trriger();
		DHT11_DataLine_Input();
		DHT11_dumi_read();

		i_RH = DHT11_rx_Data();
		d_RH = DHT11_rx_Data();
		i_Tmp = DHT11_rx_Data();
		d_Tmp = DHT11_rx_Data();

		DHT11_DataLine_Output();
		HAL_GPIO_WritePin(DHT11_PORT, DHT11_DATA_RIN, GPIO_PIN_SET);
		printf("[Tmp]%d\n",(int)i_Tmp);
		printf("[Wet]%d\n",(int)i_RH);
		// FND_update(i_Tmp*100 + i_RH);
	}
}
void DHT11_Init(void)
{
	HAL_GPIO_WritePin(DHT11_PORT, DHT11_DATA_RIN, GPIO_PIN_SET);
	HAL_Delay(3000);
	return;
}


void DHT11_trriger(void)
{
	HAL_GPIO_WritePin(DHT11_PORT, DHT11_DATA_RIN, GPIO_PIN_RESET);
	HAL_Delay(20);
	
	HAL_GPIO_WritePin(DHT11_PORT, DHT11_DATA_RIN, GPIO_PIN_SET);
	delay_us(7);
	return;
}


void DHT11_DataLine_Input(void)
{
	GPIO_InitTypeDef GPIO_InitStruct = {0};
	
	/*Configure GPIO pin : PH0 */
  GPIO_InitStruct.Pin = DHT11_DATA_RIN;
  GPIO_InitStruct.Mode = GPIO_MODE_INPUT;			//Change Output to Input
  GPIO_InitStruct.Pull = GPIO_NOPULL;
  HAL_GPIO_Init(DHT11_PORT, &GPIO_InitStruct);
	
	return;
}


void DHT11_DataLine_Output(void)
{
	GPIO_InitTypeDef GPIO_InitStruct = {0};
	
	/*Configure GPIO pin : PH0 */
  GPIO_InitStruct.Pin = DHT11_DATA_RIN;
  GPIO_InitStruct.Mode = GPIO_MODE_OUTPUT_PP;			//Change Input to Output 
  GPIO_InitStruct.Pull = GPIO_NOPULL;
  GPIO_InitStruct.Speed = GPIO_SPEED_FREQ_LOW;
  HAL_GPIO_Init(DHT11_PORT, &GPIO_InitStruct);
	
	return;
}


uint8_t DHT11_rx_Data(void)
{
	uint8_t rx_data = 0;
	
	for(int i = 0; i < 8; i++)
	{
		//when Input Data == 0
		while( 0 == HAL_GPIO_ReadPin(DHT11_PORT, DHT11_DATA_RIN) )
		{
			;
		}
#if 1
		delay_us(40);
#else  // org
		delay_us(16);
#endif
		rx_data<<=1;
		
		//when Input Data == 1
		if(HAL_GPIO_ReadPin(DHT11_PORT, DHT11_DATA_RIN))
		{
			rx_data |= 1;
		}
		while( 1 == HAL_GPIO_ReadPin(DHT11_PORT, DHT11_DATA_RIN) );
	}
	return rx_data;
}


void DHT11_dumi_read(void)
{
	while( 1 == HAL_GPIO_ReadPin(DHT11_PORT, DHT11_DATA_RIN) );
	while( 0 == HAL_GPIO_ReadPin(DHT11_PORT, DHT11_DATA_RIN) );
	while( 1 == HAL_GPIO_ReadPin(DHT11_PORT, DHT11_DATA_RIN) );
	return;
}

 

 

DHT11.h

/*
 * DHT11.h
 *
 *  Created on: 2019. 9. 2.
 *      Author: kccistc
 */

#ifndef SRC_DHT11_H_
#define SRC_DHT11_H_

#define DHT11_PORT			GPIOA
#define DHT11_DATA_RIN		GPIO_PIN_0
void DHT11_Init(void);
void DHT11_trriger(void);
void DHT11_DataLine_Input(void);
void DHT11_DataLine_Output(void);
uint8_t DHT11_rx_Data(void);
void DHT11_dumi_read(void);

#endif /* SRC_DHT11_H_ */

 

 

main.c

DHT11 Test

DHT11_main 호출

 

결과