In SX Microcontrollers, SX/B Compiler and SX-Key Tool, Beau Schwabe wrote:

JDOhio,
The high resolution is in 1/16th Deg C units.... or 0.0625  that's the best resolution obtainable from the DS1620.

Here is my revised "spin code" It basically follows the datasheet...


[code]
       tc := ReadRegister(RdTmp,9)                      ' read temp in 0.5° C units
       if tc > 255
          tc -= 512
       tc >>= 1                 'Strip LSB divide by 2  ' Scale 0.5° units to 1° units
       tc *= 100                                        ' Scale 1° units to 0.01° units
       tc -= 25                                         ' Offset adjustment for high resolution conversion
       cr := ReadRegister(RdCntr,9)                     ' read remaining counts
       cpd := ReadRegister(RdSlope,9)                   ' read counts per degree
       tc += ((cpd - cr)*100)/ cpd                      ' calculate high resolution temperature value
       Result := tc
 

  

''       Note: In the New RevE DS1620 chips released (06/05/2003), the Slope register($A9) will always 

''             read a value of 16 so it would be unnecessary to read the slope.  Simply hard code the  

''             'cpd' value in the above code with a value of 16 instead.
 
[/code]
Note for the above code.... 'tc' returns a value in x100 notation ... in other words 25 Deg C returns 2500

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