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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

60 Pa-1

240 Pa-1

Temperature

200 °C-1

200 °C-1

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).