Hi, in the color sensor twig sample code on http://garden.seeedstudio.com/index.php … nsor_v0.9b I think the line indicated below is a bug:
CODE: SELECT ALL
void calculate_xy()
{
X=(-0.14282)*red+(1.54924)*green+(-0.95641)*blue;
Y=(-0.32466)*red+(1.57837)*green+(-0.73191)*blue;
Z=(-0.68202)*red+(0.77073)*green+(0.56332)*blue;
x=X/(X+Y+Z);
y=Y/(X+Y+Z);
---------------bug–> if((X>0)&&(Y>0)&&(Z>0))
{
Serial.println(“The x,y value is”);
Serial.println(x,2);
Serial.println(y,2);
}
else
Serial.println(“Error,the value overflow”);
}
This always prints “overflow” when looking at a bright red color. If you put red=1 and green+blue=0 into the formula you will see that X, Y, and Z will all be negative, so this is normal operation rather than an overflow. It works fine if you just remove this test.
