Assembly and Wiring

Both color sensors come with all surface mount components pre-soldered. The breakout-board version comes with an optional header for breadboard use. Soldering the header is a simple process:

Assembly (breakout version only)

• 

Position the header

Trim the header to length if necessary and insert it (long pins down) into your breadboard.

• 

Position the Breakout

Place the breakout over the exposed short end of the header pins.

• 
• 
• 

And Solder!

Solder all pins to ensure good electrical contact.

Wiring

These sensors communicate via a 2-wire I2C interface. To connect to the processor, you need a total of just 4 wires.

• 

Flora Wiring:

Connect from:

• 3.3v -> 3v (red wire)
• GND -> GND (black wire)
• SDA -> SDA (white wire)
• SCL -> SCL (green wire)

• 
• 
• 

Arduino Wiring:

Connect jumpers from:

• 5v -> VIN (red wire)
• GND -> GND (black wire)
• SDA -> SDA (orange wire)
• SCL -> SCL (white wire)

Note: On older Arduinos such as the Duemilanove and pre R3 UNOs, SDA is on Analog 4 and SCL is on Analog 5.

On pre-R2 Megas, SDA is on Digtital 20 and SCL is on digital 21.

For the Leonardo, SDA is digital pin 2 and SCL is digital pin 3.

To control the LED

(Breakout version only) – The LED pin can be pulled low to turn off the LED. This can be done in three ways:

1. Wire directly to ground to turn it off completely.
2. Wire to a spare digital pin and control it with digitalWrite().
3. Wire the LED pin to the INT pin and control with setInterrupt() (See Library Reference for details).

Demo Program

#include <Wire.h>

#include “Adafruit_TCS34725.h”

// Pick analog outputs, for the UNO these three work well

// use ~560  ohm resistor between Red & Blue, ~1K for green (its brighter)

#define redpin 3

#define greenpin 5

#define bluepin 6

// for a common anode LED, connect the common pin to +5V

// for common cathode, connect the common to ground

// set to false if using a common cathode LED

#define commonAnode true

// our RGB -> eye-recognized gamma color

byte gammatable[256];

Adafruit_TCS34725 tcs = Adafruit_TCS34725(TCS34725_INTEGRATIONTIME_50MS, TCS34725_GAIN_4X);

void setup() {

  Serial.begin(9600);

  //Serial.println(“Color View Test!”);

  if (tcs.begin()) {

    //Serial.println(“Found sensor”);

  } else {

    Serial.println(“No TCS34725 found … check your connections”);

    while (1); // halt!

  }

  // use these three pins to drive an LED

#if defined(ARDUINO_ARCH_ESP32)

  ledcAttach(redpin, 12000, 8);

  ledcAttach(greenpin, 12000, 8);

  ledcAttach(bluepin, 12000, 8);

#else

  pinMode(redpin, OUTPUT);

  pinMode(greenpin, OUTPUT);

  pinMode(bluepin, OUTPUT);

#endif

  // thanks PhilB for this gamma table!

  // it helps convert RGB colors to what humans see

  for (int i=0; i<256; i++) {

    float x = i;

    x /= 255;

    x = pow(x, 2.5);

    x *= 255;

    if (commonAnode) {

      gammatable[i] = 255 – x;

    } else {

      gammatable[i] = x;

    }

    //Serial.println(gammatable[i]);

  }

}

// The commented out code in loop is example of getRawData with clear value.

// Processing example colorview.pde can work with this kind of data too, but It requires manual conversion to

// [0-255] RGB value. You can still uncomments parts of colorview.pde and play with clear value.

void loop() {

  float red, green, blue;

 

  //tcs.setInterrupt(false);  // turn on LED

  delay(60);  // takes 50ms to read

  tcs.getRGB(&red, &green, &blue);

 

  tcs.setInterrupt(true);  // turn off LED

  Serial.print(“R:t”); Serial.print(int(red));

  Serial.print(“tG:t”); Serial.print(int(green));

  Serial.print(“tB:t”); Serial.print(int(blue));

  Serial.print(“n”);

#if defined(ARDUINO_ARCH_ESP32)

  ledcWrite(1, gammatable[(int)red]);

  ledcWrite(2, gammatable[(int)green]);

  ledcWrite(3, gammatable[(int)blue]);

#else

  analogWrite(redpin, gammatable[(int)red]);

  analogWrite(greenpin, gammatable[(int)green]);

  analogWrite(bluepin, gammatable[(int)blue]);

#endif

}