QBoat Sunny 玩创意(一): 打造室内温湿度无线感测的应用－觀察筆記

物联网的蓬勃发展，让热爱研发科技产品和服务的创客们，有了挥洒无尽创意的新天地。而为了因应开发者不同的需求，市售开发版琳琅满目，凡举 Arduino、Rasberry Pi 各有相应的不同功能。而在外部连网的时代，东西有多智能，对象有什么特色，才是 IoT 竞争环境下的致胜关键。

由 QNAP 推出的微型单板服务器 QBoat Sunny ，可视为小型 NAS，特别适合做为携带型的 IoT Gateway！不仅兼容于物联网通讯协议 MQTT ，还可以 Node-red 为基础下去开发应用程序。然而其与 NAS 最大不同在于容量的限制。QBoat Sunny 使用固态硬盘(SSD)，虽容量无法与传统硬盘(HDD)比拟，但已足以用于边缘运算。

「不过是压低成本改用 ARM 当 base，把硬盘改成 SSD 做的 NAS」或许是很多人对 QBoat Sunny 的评价，然而 NAS 并不仅只是 PC 灌个 Windows 或 Linux 作为档案与数据库的服务器，软硬件的良好整合性，能适时提供用户需要的服务功能才是其核心价值。以下的范例操作，是为了以无线感测的方式，让使用者能用网页方式查询室内的温湿度。就来看看作为小型 NAS 的 QBoat Sunny 在「打造无线感测应用」，有多轻松省事吧！

基础架构

准备工具及操作方式

Media Tek Linklt 7697 开发版 + DHT11

1. 连接 MTK 7697 开发版及DHT 11，其脚位连接方式如下：

DHT11	MediaTek LinkIt 7697
+	5V
–	GND
DO	P3

2. 透过 LWiFi 连结 Wireless AP router，并套用 DHT11 的链接库。编译完成后可用浏览器，如 : http://192.168.1.xxx/temp 查看是否能传出感测数值。

GET參數	功用
/temp	取得攝氏溫度
/humi	取得濕度百分比值

完整程序代码如下:

<strong>&lt;&lt; MonitorNode.ino &gt;&gt;</strong>


 #include &lt;LWiFi.h&gt;

 #include "DHT.h"



#define DHTPIN 3 // what digital pin we’re connected to

 #define WARNPIN 13



// Uncomment whatever type you’re using!

 #define DHTTYPE DHT11 // DHT 11

 //#define DHTTYPE DHT22 // DHT 22 (AM2302), AM2321

 //#define DHTTYPE DHT21 // DHT 21 (AM2301)

 DHT dht(DHTPIN, DHTTYPE);



char ssid[] = “LaisanHere”; // your network SSID (name)

 char pass[] = “t101419008”; // your network password

 int keyIndex = 0; // your network key Index number (needed only for WEP)



int status = WL_IDLE_STATUS;



WiFiServer server(80);



void setup() {

 //Initialize serial and wait for port to open:

 Serial.begin(9600);

 while (!Serial) {

 ; // wait for serial port to connect. Needed for native USB port only

 }



// attempt to connect to Wifi network:

 while (status != WL_CONNECTED) {

 Serial.print(“Attempting to connect to SSID: “);

 Serial.println(ssid);

 // Connect to WPA/WPA2 network. Change this line if using open or WEP network:

 status = WiFi.begin(ssid, pass);

 }

 server.begin();

 // you’re connected now, so print out the status:

 printWifiStatus();



// Activate DHT11

 dht.begin();



pinMode(WARNPIN, OUTPUT);

 digitalWrite(WARNPIN, LOW);

 }

 void loop() {

 // listen for incoming clients

 WiFiClient client = server.available();

 if (client) {

 Serial.println(“new client”);



String msg;

 String param;



// an http request ends with a blank line

 if (client.connected()) {

 while (client.available()) {

 char c = client.read();

 msg += String(c);

 }

 }



Serial.print(msg);



int posi = msg.indexOf(“Referer: “);

 if(posi &gt; 0)

 {

 String sb = msg.substring(posi);

 int p = sb.indexOf(“/”);

 param = sb.substring(p+2);

 p = param.indexOf(“/”);

 param = param.substring(p, p+5);

 }

 else

 {

 posi = msg.indexOf(“GET”);

 param = msg.substring(posi+4, posi+9);

 }



Serial.println(param);



// send a standard http response header

 client.println(“HTTP/1.1 200 OK”);

 client.println(“Content-Type: text/html”);

 client.println(“Connection: close”); // the connection will be closed after completion of the response

 client.println();



if(param == “/warn”)

 {

 digitalWrite(WARNPIN, HIGH);

 client.println(“WARNING !!”);

 }

 if(param == “/cler”)

 {

 digitalWrite(WARNPIN, LOW);

 client.println(“CLEAR”);

 }

 if(param == “/temp”)

 {

 float t = dht.readTemperature();

 client.println(t);

 }

 if(param == “/humi”)

 {

 float h = dht.readHumidity();

 client.println(h);

 }



// close the connection:

 client.stop();

 Serial.println(“client disonnected”);

 }



// give the web browser time to receive the data

 delay(100);

 }



void printWifiStatus() {

 // print the SSID of the network you’re attached to:

 Serial.print(“SSID: “);

 Serial.println(WiFi.SSID());



// print your WiFi shield’s IP address:

 IPAddress ip = WiFi.localIP();

 Serial.print(“IP Address: “);

 Serial.println(ip);



// print the received signal strength:

 long rssi = WiFi.RSSI();

 Serial.print(“signal strength (RSSI):”);

 Serial.print(rssi);

 Serial.println(” dBm”);

 }