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Version 0.8 – January 2017

10/14

5.4

Checksum Calculation

The checksum byte is generated by a CRC algorithm with the following properties:

Property

Value

Name

CRC-8

Protected data

read data

Width

8 bit

Polynomial

0x31 (x8 + x5 + x4 +1)

Initialization

0xFF

Reflect input

False

Reflect output

False

Final XOR

0x00

Example

CRC(0xBEEF) = 0x92

5.5

Conversion to Physical Values

Conversion of the differential pressure and temperature sensor signals to a physical value is done with the scale factor.

5.5.1 Scale Factors

Parameter

SDP31

SDP32

Differential Pressure

Temperature

5.5.2 Differential Pressure

The digital calibrated differential pressure signal read from the sensor is a signed integer number (two's complement number).

The integer value can be converted to the physical value by dividing it by the scale factor (differential pressure in Pascal =

sensor output

 scale factor).

5.5.3 Temperature

The digital calibrated temperature signal read from the sensor is a signed integer number (two's complement number). The

integer value can be converted to the physical value by dividing it by the scale factor (temperature in °C = sensor output



scale factor).