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Internet of Things Programming with JavaScript

You're reading from  Internet of Things Programming with JavaScript

Product type Book
Published in Feb 2017
Publisher Packt
ISBN-13 9781785888564
Pages 298 pages
Edition 1st Edition
Languages

Table of Contents (15) Chapters

Internet of Things Programming with JavaScript
Credits
About the Author
www.packtpub.com
Customer Feedback
Preface
Getting Started with Raspberry Pi Zero Connecting Things to the Raspberry Pi Zero Connecting Sensors - Measure the Real Things Control-Connected Devices Adding a Webcam to Monitor Your Security System Building a Web Monitor and Controlling Devices from a Dashboard Building a Spy Police with the Internet of Things Dashboard Monitoring and Controlling Your Devices from a Smart Phone Putting It All Together

Measuring the humidity for plants


In this section, we will see the testing of humidity inside a plant and the soil using a sensor:

I will now go through the main parts of this first piece of code. Then we set up the serial communication: 

int value;   
 
void setup() { 
Serial.begin(9600); 
}  

In the main loop, we will read the analog signal from the sensor:

void loop(){   
Serial.print("Humidity sensor value:"); 
Value = analogRead(0);   
Serial.print(value);   

We compare the value of the sensor and display the result on the serial interface:

if (Value<= 300)   
Serial.println(" Very wet");   
if ((Value > 300) and (Value<= 700))   
Serial.println(" Wet, do not water");    
if (Value> 700)   
Serial.println(" Dry, you need to water");  
delay(1000);  
} 

Here, the screenshot shows the results of the readings:

The following screenshot shows that the plant doesn't require water;  because it has enough...

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