SHIP:Data Types:Temperature

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The Temperature datatype is returned by the pcbTemp portvar (the exact format is configured by setting tempPrecision).

Data Type	Description
Temperature	16 bit fixed-point-integer in which the upper portion is in whole degrees and the lower portion is in 256ths of a degree. Set shipCelsius to true for Celsius, or false for Fahrenheit.

Generically, the value read from pcbTemp is an 8-bit value in whole degrees followed by a tempPrecision-bit value in 1/256ths of a degree. The following are examples on how to properly interpret a Temperature value:

By default tempPrecision is 0:

SIMTempWhole = GPIO.pcbTemp;  // the value is good as-is
SIMTempFrac  = 0;             // unnecessary

For handling any other value of tempPrecision:

SIMTempWhole = (GPIO.pcbTemp >> GPIO.tempPrecision);                  // once the fractional bits are gone, the value is correct
SIMTempFrac  = (GPIO.pcbTemp & (0x00FF >> (8 - GPIO.tempPrecision))); // get rid of the degree bits
SIMTempFrac  = (SIMTempFrac << (8 - GPIO.tempPrecision));             // re-adjust the fractional bits
SIMTempFrac  = (SIMTempFrac*100)/256;                                 // fix up the value to be a proper fraction (currently it is from 0/256 to 255/256 of a degree)

Note: SIMTempWhole and SIMTempFrac only need to be of type Byte to fit the highest possible values