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Version 3.3 – November 2024

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3.3.15 Read product identifier

During assembly and start-up of the device it might be required to check some basic parameters in the sensor

- for example to check if the correct sensor is integrated.

The product identifier and serial number can be read out after sending a sequence of two commands.

Command

Command

code (hex)

Consecutive read

Description

Read product

identifier

0x367C

0xE102

Byte1: Product number

[31:24]

Byte2: Product number

[23:16]

Byte3: CRC

Byte4: Product number [15:8]

Byte5: Product number [7:0]

Byte6: CRC

Byte7: Serial number [63:56]

Byte8: Serial number [55:48]

Byte9: CRC

Byte10: Serial number [47:40]

Byte11: Serial number [39:32]

Byte12: CRC

Byte13: Serial number [31:24]

Byte14: Serial number [23:16]

Byte15: CRC

Byte16: Serial number [15:8]

Byte17: Serial number [7:0]

Byte18: CRC

Note that both commands need to be

preceded with an I2C write header

(I2C address + W).

The second command returns:

-

32-bit unique product and

revision number. The number

is listed in the table below.

Note that the last 8 bits are

the revision number and can

be subject to change.

-

64-bit unique serial number

as ASCII representation of the

serial number on the sensor.

Product

Product number

STC31-C

0x08010304

3.4 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