[Tinyos-help] About Temperature

[Yanchuan Li]

Anyone knows how to convert a ADC reading into real Degrees for temperature?
On the Manual, it's said like following:

The mote’s ADC output can be converted to degrees Kelvin using the following approximation over 0-50 °C: 1/T(K) = a + b × ln(Rthr) + c × [ln(Rthr)]3
where:
Rthr = R1(ADC_FS-ADC)/ADC
a = 0.00130705
b = 0.000214381
Page 10 Doc. # 7430-0020-03 Rev. B
MTS/MDA Sensor Board User’s Manual
Wireless Sensor Networks
c = 0.000000093
R1 = 10 kΩ
ADC_FS = 1023
ADC = output value from mote’s ADC measurement.

BUT I always got readings like between 500-600. And when I using the function above, I got some really weird numbers after calculation.
  double a = 0.00130705;
  double b = 0.000214381;
  double c = 0.000000093;
  double r1 = 10;
  double adc_fs = 1023;
  double adc = 600;
  double rthr = (r1 * (adc_fs - adc))/adc;
  double temp = Math.log10(rthr);
  double temp1=Math.pow(temp, 3);
  double temp3=a+b*temp+c*temp1; 
  System.out.println(1/temp3);

RESULT: 671.6176617203942
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