Published May 23, 2014

Turning on a light when it gets dark

In this tutorial you will learn how to use a Grove Light Sensor and connect it to a SODAQ Moja and a Blue LED.

Full instructions provided820

Things used in this project

Hardware components

SODAQ Moja

0.5W Solar Panel

1aH battery pack

Grove Light Sensor

Grove Blue LED

Grove w/o Buckle Cable (any length)

Story

Final assembly

1 / 2

0.5W Solar Panel

SODAQ Moja

1aH battery pack

Grove Light Sensor

Grove Blue LED

Grove w/o Buckle Cable (any length)

Instructions

First, plug the Light sensor into the A0/A1 pin in the always on row.

Then, plug the Blue LED into the D4/D5 pin in the always on row.

Next, plug the 0.5W solar panel and the 1A LiPo battery into the respective sockets (see http://www.sodaq.net/#!getting-started/c21mafor a board diagram)

Turn on the SODAQ board, compile and upload the following sketch from the arduino IDE onto the SODAQ Board, and then unplug the USB cable from the computer when it is working.

Code

Download

#include <math.h>
const int ledPin=4;
  //Connect the LED Grove module to Pin4, Digital 4
const int thresholdvalue=50;
  //The threshold for which the LED should turn on.
float Rsensor; //Resistance of sensor in K
 
void setup() {
 pinMode(ledPin,OUTPUT); //Set the LED on Digital 4 as an OUTPUT
}
 
void loop() {
 int sensorValue = analogRead(0);
 Rsensor=(float)(1023-sensorValue)*10/sensorValue; 
 if(Rsensor>thresholdvalue)
 {
  digitalWrite(ledPin,HIGH);
 }
 else
 {
  digitalWrite(ledPin,LOW);
 }
}

code.c

#include <math.h>
const int ledPin=4;
  //Connect the LED Grove module to Pin4, Digital 4
const int thresholdvalue=50;
  //The threshold for which the LED should turn on.
float Rsensor; //Resistance of sensor in K
 
void setup() {
 pinMode(ledPin,OUTPUT); //Set the LED on Digital 4 as an OUTPUT
}
 
void loop() {
 int sensorValue = analogRead(0);
 Rsensor=(float)(1023-sensorValue)*10/sensorValue; 
 if(Rsensor>thresholdvalue)
 {
  digitalWrite(ledPin,HIGH);
 }
 else
 {
  digitalWrite(ledPin,LOW);
 }
}

Credits

Ollie Smeenk

8 projects • 6 followers

Business-oriented Tinkerer! Ready to engage in any project for- and not for profit!

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Turning on a light when it gets dark

Turning on a light when it gets dark

Things used in this project

Hardware components

Story

Final assembly

Instructions

Code

Code

Code

code.c

Credits

Ollie Smeenk

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