/*
BM017_Arduino_color_sensing:  This program interfaces to the AMS TCS34725 color light
to digital converter IC.  It uses the Arduino I2C interface.  
*/

#include <Wire.h>
#include <Math.h>

byte i2cWriteBuffer[10];
byte i2cReadBuffer[10];
int LEDSRED=7; //output to red leds pwm
int LEDSBLUE=8; //output to Blue leds pwm
int LEDSGREN=9;//output to Green leds pwm

#define SensorAddressWrite 0x29 //
#define SensorAddressRead 0x29 // 
#define EnableAddress 0xa0 // register address + command bits
#define ATimeAddress 0xa1 // register address + command bits
#define WTimeAddress 0xa3 // register address + command bits
#define ConfigAddress 0xad // register address + command bits
#define ControlAddress 0xaf // register address + command bits
#define IDAddress 0xb2 // register address + command bits
#define ColorAddress 0xb4 // register address + command bits

/*  
Send register address and the byte value you want to write the magnetometer and 
loads the destination register with the value you send
*/
void Writei2cRegisters(byte numberbytes, byte command)
{
    byte i = 0;

    Wire.beginTransmission(SensorAddressWrite);   // Send address with Write bit set
    Wire.write(command);                          // Send command, normally the register address 
    for (i=0;i<numberbytes;i++)                       // Send data 
      Wire.write(i2cWriteBuffer[i]);
    Wire.endTransmission();

    delayMicroseconds(100);      // allow some time for bus to settle      
}

/*  
Send register address to this function and it returns byte value
for the magnetometer register's contents 
*/
byte Readi2cRegisters(int numberbytes, byte command)
{
   byte i = 0;

    Wire.beginTransmission(SensorAddressWrite);   // Write address of read to sensor
    Wire.write(command);
    Wire.endTransmission();

    delayMicroseconds(100);      // allow some time for bus to settle      

    Wire.requestFrom(SensorAddressRead,numberbytes);   // read data
    for(i=0;i<numberbytes;i++)
      i2cReadBuffer[i] = Wire.read();
    Wire.endTransmission();   

    delayMicroseconds(100);      // allow some time for bus to settle      
}  

void init_TCS34725(void)
{
  i2cWriteBuffer[0] = 0x10;
  Writei2cRegisters(1,ATimeAddress);    // RGBC timing is 256 - contents x 2.4mS =  
  i2cWriteBuffer[0] = 0x00;
  Writei2cRegisters(1,ConfigAddress);   // Can be used to change the wait time
  i2cWriteBuffer[0] = 0x00;
  Writei2cRegisters(1,ControlAddress);  // RGBC gain control
  i2cWriteBuffer[0] = 0x03;
  Writei2cRegisters(1,EnableAddress);    // enable ADs and oscillator for sensor  
}

void get_TCS34725ID(void)
{
  Readi2cRegisters(1,IDAddress);
  if (i2cReadBuffer[0] = 0x44)
    Serial.println("TCS34725 is present");    
  else
    Serial.println("TCS34725 not responding");    
}

/*
Reads the register values for clear, red, green, and blue.
*/
void get_Colors(void)
{
  unsigned int clear_color = 0;
  unsigned int red_color = 0;
  unsigned int green_color = 0;
  unsigned int blue_color = 0;

  Readi2cRegisters(8,ColorAddress);
  clear_color = (unsigned int)(i2cReadBuffer[1]<<8) + (unsigned int)i2cReadBuffer[0];
  red_color = (unsigned int)(i2cReadBuffer[3]<<8) + (unsigned int)i2cReadBuffer[2];
  green_color = (unsigned int)(i2cReadBuffer[5]<<8) + (unsigned int)i2cReadBuffer[4];
  blue_color = (unsigned int)(i2cReadBuffer[7]<<8) + (unsigned int)i2cReadBuffer[6];

  analogWrite(LEDSRED, red_color);
  analogWrite(LEDSBLUE, blue_color); 
  analogWrite(LEDSGREN, green_color);

}  

void setup() {
  Wire.begin();
  Serial.begin(9600);  // start serial for output
  init_TCS34725();
  get_TCS34725ID();     // get the device ID, this is just a test to see if we're connected
}

void loop() {
    get_Colors();
    delay(1000);
}