Photosynthesis Detection System

Save the Earth with this light detector which measures and displays the light intensity in an environment.

IntermediateFull instructions provided996

Things used in this project

Hardware components

Texas Instruments EK-TM4C123GXL TM4C Tiva LaunchPad

Seeed Studio Grove Starter Kit for LaunchPad

Seeed Studio Grove - Light Sensor

Seeed Studio Grove - 4-Digit Display

SparkFun 4 Pin RGB LED

Software apps and online services

Texas Instruments Energia

Hand tools and fabrication machines

Laser cutter (generic)

Story

Everyone says they want to save the Earth, but with this project, we may have actually done it! Our revolutionary light detection system produces a 4-digit-display value and an intense color based on the intensity of light in the environment. If the LED glows RED, you might have too much light. If it glows BLUE, there's too little light. The Goldilocks color is PURPLE, so if you see this color, the light is just right.

Whether this project stops global warming or just prevents your plants from dying, we know you'll enjoy making it and looking at the pretty colors!

Build Instructions:

1. Connect the Tiva Launchpad to the Bottom of the Grove Base

2. Connect the light sensor to J6(A)

3. Connect the 4-digit display to J14(D)

4. Connect the RGB LED to the Launchpad as shown in the diagram below

Optional Box:

1. See diagrams below to create the aesthetically pleasing box that surrounds the wires in our project (laser cutter required)

2. After build is finished, put all components except the light sensor and USB cable inside the box

Operation Instructions:

1. Connect the Launchpad to your computer with the provided Micro USB Cable

2. Open Energia and the run provided code for the light detection sensor

3. Enjoy your finished product!

Code

Light Detector System

/*
 Light Detection System

 A simple program that displays the value of light from the Grove Light Sensor on the Grove 4-Digit Display and turns the RGB LED a specific color depending on the value of light
 
 The circuit:
 * 4-Digit Display attached to Pin 38 and 39 (J14 plug on Grove Base BoosterPack)
 * Light Sensor attached to Pin 24 (J6 plug on Grove Base BoosterPack)
 * RGB LED connected to pins defined below
*/

//4-Digit Display library
#include "TM1637.h" 

/* Macro Define */
#define CLK               39                  /* 4-Digit Display clock pin */
#define DIO               38                 /* 4-Digit Display data pin */
#define LIGHT_SENSOR      24                 /* pin connected to the Light Sensor */

/* Global Variables */
TM1637 tm1637(CLK, DIO);                  /* 4-Digit Display object */
int analog_value = 0;      
int new_value = 0;
/* variable to store the value coming from Light Sensor */
int8_t bits[4] = {0};                     /* array to store the single digits of the value */



 /*

 Hardware Required for RGB LED Section
 * TI LaunchPad
 * Breadboard BoosterPack
 * Breadboard
 * RGB LED
 * 4x Jumper Wires

*/

// Connect Anode pin to VCC
// Connect Red to pin 19 which should be PWM capable
// Connect Green to pin with PWM
// Connect Blue to pin with PWM

#define RED 19 // pin 19 is always PWM capable according to LaunchPad standard
#define GREEN 18 // may need to change this for your LaunchPad
#define BLUE 11 // may need to change this for your LaunchPad
#define delayTime 10 // delay between color changes, 10ms by default

int redVal;
int greenVal;
int blueVal;


void setup() 
{
  /* Initialize 4-Digit Display */
  tm1637.init();
  tm1637.set(BRIGHT_TYPICAL);

  pinMode(RED, OUTPUT);
  pinMode(GREEN, OUTPUT);
  pinMode(BLUE, OUTPUT);

}


void loop() 
{
  analog_value = analogRead(LIGHT_SENSOR);        /* read the value from the sensor */
  int PWM_RESOLUTION = 255; // this variable will hold our resolution.
  memset(bits, 0, 4);                             /* reset array before we use it */
  for(int i = 3; i >= 0; i--) 
  {
    /* Convert the value to individual decimal digits for display */
    bits[i] = analog_value % 10;
    analog_value = analog_value / 10;  
    tm1637.display(i, bits[i]);    
  }
      //analog_value = analog_value*10;
    
  if(bits[0]>=2) // bright - red
  {
    int redVal = 0; // zero voltage will give us full color
    int blueVal = PWM_RESOLUTION; // max voltage will give us no color
    analogWrite( RED, redVal );
    analogWrite( BLUE, blueVal );
  }

  else if(bits[0]>=1) // middle - purple
  {
    int redVal = PWM_RESOLUTION/2; // half voltage gives us half color
    int blueVal = PWM_RESOLUTION/2; // half voltage gives us half color
    analogWrite( RED, redVal );
    analogWrite( BLUE, blueVal );
  }


  else // dark - blue
  {
    int redVal = PWM_RESOLUTION; // max voltage will give us no color
    int blueVal = 0; // zero voltage will give us full color
    analogWrite( RED, redVal );
    analogWrite( BLUE, blueVal );
  }

 
  delay(100);  //small delay so that the number doesn't change too quickly to read
 
}