Difference between revisions of "Matrix - Temperature and Humidity Sensor"

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(Introduction)
(Introduction)
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==Introduction==
 
==Introduction==
 
[[File:TemperatureAndHumiditySensor01.png|thumb|Temperature and Humidity Sensor]]
 
[[File:TemperatureAndHumiditySensor01.png|thumb|Temperature and Humidity Sensor]]
This module utilizes the DHT11 temperature and humidity sensor. The DHT11 sensor's relative humidity range is 20%-80% ±5% and its temperature range is 0℃-50℃ ±2℃. DHT11's DATA is a single bus which needs only a single I/O. 线用于微处理器与 DHT11之间的通讯和同步,采用单总线数据格式, 仅仅需要一个 I/O 口,一次通讯时间4ms左右,数据分小数部分和整数部分,数据采用校验和方式进行校验。它应用专用的数字模块采集技术和温湿度传感技术,超小的体积、极低的功耗,信号传输距离可达20米以上。适合要求不高的场合使用。我们把DHT11的4针引脚简化为3针引出,并在PCB上加上固定孔,方便您安装使用。
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This module utilizes the DHT11 temperature and humidity sensor. The DHT11 sensor's relative humidity range is 20%-80% ±5% and its temperature range is 0℃-50℃ ±2℃. DHT11 uses a single bus communication which needs only one data line. DATA is used for communication and synchronization between the microprocessor and DHT11. Its data format consists of the 8bit humidity integer data and 8bit the Humidity decimal data, and 8 bit temperature integer data and 8bit fractional temperature data and 8 bit parity bit. Its application of a dedicated digital modules collection technology and the temperature and humidity sensing technology, to ensure that the product has high reliability, excellent long-term stability, low cost and long distance (up to 20 meters) signal transmission. We simplified the DHT11's 4-pin to 3-pin.
  
 
==特性==
 
==特性==

Revision as of 08:41, 5 August 2015

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1 Introduction

Temperature and Humidity Sensor

This module utilizes the DHT11 temperature and humidity sensor. The DHT11 sensor's relative humidity range is 20%-80% ±5% and its temperature range is 0℃-50℃ ±2℃. DHT11 uses a single bus communication which needs only one data line. DATA is used for communication and synchronization between the microprocessor and DHT11. Its data format consists of the 8bit humidity integer data and 8bit the Humidity decimal data, and 8 bit temperature integer data and 8bit fractional temperature data and 8 bit parity bit. Its application of a dedicated digital modules collection technology and the temperature and humidity sensing technology, to ensure that the product has high reliability, excellent long-term stability, low cost and long distance (up to 20 meters) signal transmission. We simplified the DHT11's 4-pin to 3-pin.

2 特性

  • 测量范围 湿度20-80%RH, 温度0~50℃
  • 测量精度 湿度+-5%RH, 温度+-2℃
  • 一线协议
  • 2.54mm排针接口,接线方便,通用性强

3 使用方法

3.1 连接

  • 连接到Tiny4412 SDK (1506)
GND针脚: 接地
VCC: 接5V
S针脚:接GPIO PIN1, 必须使用中断引脚,可用引脚(1、2、3、4、9、10)

3.2 Linux下的C示例

#include <stdio.h>
#include <stdlib.h>
#include "libfahw.h"
 
void parseCmd(int argc, char **argv, int *pin)
{
    int num = atoi(argv[1]);
    switch(num) {
    case 1:
        *pin = TINY4412_GPIO_PIN1;
        break;
    case 2:
        *pin = TINY4412_GPIO_PIN2;
        break;
    case 3:
        *pin = TINY4412_GPIO_PIN3;
        break;
    case 4:
        *pin = TINY4412_GPIO_PIN4;
        break;
    case 9:
        *pin = TINY4412_GPIO_PIN9;
        break;
    case 10:
        *pin = TINY4412_GPIO_PIN10;
        break;
    default:
        printf("Unsupported pin TINY4412_GPIO_PIN%d\n", num);
        num = 1;
        *pin = TINY4412_GPIO_PIN1;
    }
    printf("Using pin TINY4412_GPIO_PIN%d\n", num);
}
 
int main(int argc, char ** argv)
{
    int ret = -1;
    int dhtTemp = 0;
    int dhtHdty = 0;
    int devFD = -1;
    int pin = TINY4412_GPIO_PIN1;
 
    if (argc == 2) {
        parseCmd(argc, argv, &pin);
    } else {
        printf("Using default pin TINY4412_GPIO_PIN1\n");
    }
    if ((devFD = dht11Init(pin)) == -1) {
        printf("Fail to init dht11\n");
        return -1;
    }
 
    if ((ret = dht11Read(DHT_HUMIDITY, &dhtHdty)) != -1) {
        printf("Get humidity : %d\n", dhtHdty);
    } else {
        printf("Faided to get humidity\n");
    }
 
    if ((ret = dht11Read(DHT_TEMP, &dhtTemp)) != -1) {
        printf("Get temperature : %d\n", dhtTemp);
    } else {
        printf("Faided to get temperature\n");
    }
 
    dht11DeInit(devFD);
    return ret;
}

3.3 编译并运行示例

git clone http://github.com/friendlyarm/fa-hardware.git
cd fa-hardware
cd demo
cd matrix-temperature_and_humidity_sensor
make

将编译生成的dht11通过ftp上传到开发板上运行即可测试。

4 相关资料