GetDeviceTwin (FB)

FUNCTION_BLOCK GetDeviceTwin EXTENDS CBM.ETrigTo

Reads the device twin from the Microsoft AZURE IoT Hub via HTTPS.

InOut:

Scope

Name

Type

Comment

Inherited from

Input

xExecute

BOOL

Rising edge: Action starts
Falling edge: Resets outputs
If a falling edge occurs before the function block has completed its action, the outputs operate in the usual manner and are only reset if either the action is completed or in the event of an error. In this case, the corresponding output values (xDone, xError) are present at the outputs for exactly one cycle.

ETrigTo

udiTimeOut

UDINT

Defines the time (µs) after which an FB (e.g. requiring an external acknowledgement) aborts operation due to a timeout with error message.

ETrigTo

Output

xDone

BOOL

TRUE: Action successfully completed

ETrigTo

xBusy

BOOL

TRUE: Function block active

ETrigTo

xError

BOOL

TRUE: Error occurred, function block aborts action
FALSE: No error

ETrigTo

Input

sHubDomainName

STRING(255)

Domain name of the IoT Hub

sDeviceId

STRING(255)

Device ID

wsSaS

WSTRING(255)

Shared Access Signature (SAS Token)

Output

eError

IOT_HUB_CLIENT_ERROR

Error code

iHttpStatus

INT

HTTP status

wsData

WSTRING(WEB_CLIENT.g_udiMaxResponseSize)

The device twin (JSON data)