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[on:]

Hello, I'm trying to use a parallax color sensor (specs at http://www.parallax.com/Portals/0/Downloads/docs/prod/acc/TCS3200_doc.pdf ) I'm checking the colors' frequencies using the Serial Monitor on my computer. However, I'm only getting a reading for the green color duration. Even then, I'm not getting any variance with different colors. I'm not exactly sure if it's a programming error or if the sensor is malfunctioning, but I would love some help. I think it may have something to do with the outputs(S2 and S3). Thanks for all your help.

Code:

[
/*optimal distance for calibration is 2.5 in*/
int Out = 13;                 //C Input "the Read"?
int S0= 8;                 //A Output
int S1 = 9;                //B Output
int S2= 10;                  //E Output
int S3 = 12;                 //F Output
int LED = 11;                 //D Output-turns on LEDS

unsigned long REDduration;
unsigned long GREENduration;
unsigned long BLUEduration;
unsigned long CLEARduration;


void setup () {
 pinMode(LED,OUTPUT);
 pinMode(Out,INPUT);
 pinMode(S0,OUTPUT);
 pinMode(S1,OUTPUT);
 pinMode(S2,OUTPUT);
 pinMode(S3,OUTPUT);
 digitalWrite(LED, HIGH);
 Serial.begin(9600);
}

void loop () {
  digitalWrite(S0,HIGH);
  digitalWrite(S1,HIGH);
  color ();
  Serial.print("R");
  Serial.println(REDduration);
  Serial.print("G");
  Serial.println(GREENduration);
  Serial.print("B");
  Serial.println(BLUEduration);
  Serial.print("C");
  Serial.println(CLEARduration);
}

void color () {
digitalWrite(S2,LOW);
digitalWrite(S3,LOW);
 REDduration= pulseIn(Out,HIGH);
digitalWrite(S2,LOW);
digitalWrite(S3,HIGH);
 BLUEduration= pulseIn(Out,HIGH);
digitalWrite(S2,HIGH);
digitalWrite(S3,LOW);
 CLEARduration= pulseIn(Out,HIGH);
digitalWrite(S2,HIGH);
digitalWrite(S3,HIGH);
GREENduration= pulseIn(Out,HIGH);

}]

[Reply #1 on:]

There is already an LED with resistor connected to pin 13. That usually means it's not the best choice for an input pin. Try a different input pin.

[Reply #2 on:]

Thank you I did not think of that. I changed it to pin 7, but now it's only reading CLEARduration. Any thoughts?

[Reply #3 on:]

What values do you get? Do they vary when you vary what you point to? Do the vary if you have the illumination LED On/Off?

I have never used this sensor, so I am just guessing here. Firstly I would pull the S0 (using the names in the PDF you refer to) LOW so we divide the output frequency by 50. This may possibly give a slow enough frequency for the pulseIn() to return a more usefull value.
The example code in the PDF counts pulses, the Arduino measures pulsewidth. Assuming the same wave shape, then at higher frequencies the pulsewidth should be narrower.
I do not like using interrupts but this may be the right place to do it, to get a count of pulses rather than the pulswidth - at the possible 600Khz that is 2 microseconds which pulsewidth() may/may not catch.

[Reply #4 on:]

Thanks for the help. I worked it out now. I just disconnected the S0 and S1 inputs. I know this is probably not correct, but I'm getting consistent readings. If it starts malfunctioning again, I'll be sure and try your suggestions!

[Reply #5 on:]

Nevermind, the numbers I'm getting are just garbage. They don't change no matter what color is in front on the sensor. I also tried LED light to see if it was too dark, but that didnt change the values either. Please Help!

[Reply #6 on:]

I'm trying, I'm trying ...  but I need something to work on.

What happened by tying S0 low to get a slower frequency? And please do post the values ... others might see a pattern or get a clue to your problem.

And I also think a circuit diagram might tell us something.