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Version 1.1 – April 2021

16/22

3.9.3

perform_self_test

Description: The perform_self_test feature can be used as an end-of-line test to check sensor functionality and the customer

power supply to the sensor.

Write

(hexadecimal)

Input parameter: -

Response parameter: sensor status

Max. command

duration [ms]

length [bytes]

signal conversion

length [bytes]

signal conversion

0x3639

-

-

3

word[0] = 0 → no malfunction detected

word[0] ≠ 0 → malfunction detected

10000

Example: perform self-test, no malfunction detected

Write

0x3639

(hexadecimal)

Command

Wait

10000 ms

command execution time

Response

0x0000

0x81

(hexadecimal)

No malfunction detected

CRC of 0x0000

3.9.4

perfom_factory_reset

Description: The perform_factory_reset command resets all configuration settings stored in the EEPROM and erases the

FRC and ASC algorithm history.

Write

(hexadecimal)

Input parameter: -

Response parameter: -

Max. command

duration [ms]

length [bytes]

signal conversion

length [bytes]

signal conversion

0x3632

-

-

-

-

1200

Example: perform factory reset

Write

0x3632

(hexadecimal)

Command

3.9.5

reinit

Description: The reinit command reinitializes the sensor by reloading user settings from EEPROM. Before sending the reinit

command, the stop measurement command must be issued. If the reinit command does not trigger the desired re-initialization,

a power-cycle should be applied to the SCD4x.

Write

(hexadecimal)

Input parameter: -

Response parameter: -

Max. command

duration [ms]

length [bytes]

signal conversion

length [bytes]

signal conversion

0x3646

-

-

-

-

20

Example: reinit

Write

0x3646

(hexadecimal)

Command re-initialization