3 Replies Latest reply on Dec 23, 2014 7:34 PM by DaKn_263916

    RTD to Temperature API


      I note in the example that the RTD_GetTemperature() API returns a 32 bit unsigned int.


      I have written code based on the example and find that I cannot display values below 0. Casting the int as a foat does not convert the negative (I assume 2's complement) value into the appropriate negative temperature value.


      Is there a convenient conversion or do we need to manually do a 2's complement on the resistance value?


      rtdRes = (rtdVoltage * CAL_REF_RESISTOR / rtdCalVoltage) * 1000;  //convert to mOhms


      rtdTemp = RTD_GetTemperature(rtdRes);    //Returns 2's complement value when rtdRes < 100,000 mOhms (PT100)


      tempdisp = (float) (rtdTemp/100.0);