FB_VN_ReadContainer

Syntax

Definition:

FUNCTION_BLOCK FB_VN_ReadContainer
VAR_INPUT
    sFilePath       : STRING;
    ipDestContainer : Reference To  ITcVnContainer;
    nDestTypeGuid   : GUID;
    bRead           : BOOL;
    nTimeout        : TIME;
END_VAR
VAR_OUTPUT
    bBusy           : BOOL;
    bError          : BOOL;
    nErrorId        : UDINT;
END_VAR

Inputs

Name	Type	Default	Description
sFilePath	STRING		Full path of the file or relative path to the default directory on the target pc
ipDestContainer	Reference To ITcVnContainer		Returns a container with the loaded content
nDestTypeGuid	GUID		The type id of the container to return. If this parameter is not set, a suitable container type will be determined automatically (except for csv files).
bRead	BOOL		Reading the file is triggered by a rising edge at this input.
nTimeout	TIME	VISION_ADS_TIMEOUT	Indicates the time before the function is cancelled.

Outputs

Name	Type	Description
bBusy	BOOL	This output remains TRUE until the function block has executed a command, but at the longest for the duration supplied to the 'nTimeout' input. While bBusy = TRUE, no new command will be accepted at the inputs.
bError	BOOL	This output is switched to TRUE as soon as an error occurs during the execution of a command. The command-specific error code is contained in ‘nErrorId’. If the function block has a timeout error, 'bError' is TRUE and 'nErrorId' is 1861 (hexadecimal 0x745). Is reset to FALSE by the execution of a command at the inputs.
nErrorId	UDINT	Contains the ADS error code or the command-specific error code of the last executed command. Is reset to 0 by the execution of a command at the inputs.

Weiterführende Informationen

Der Funktionsblock FB_VN_ReadContainer lädt einen Container aus einer Datei asynchron in die SPS.

	Laden von geänderten Containern. Beim Einladen der Container cached der Vision-Service die Daten intern. Ein Einladen von geänderten Containern ist somit im Standard nicht möglich. Passen Sie dazu die die Cache Einstellungen an oder sehen Sie das Beispiel Serielles Laden von Bildern in die SPS für eine Alternative.

Parameter

Einige Parameter sind zentral in der Sektion File Access Parameter beschrieben.

Container-Typ

Der Container-Typ des zu ladenden Containers kann optional angegeben werden.

Geladener Container ^{(Rückgabewert)}

Der geladene Container ist nach erfolgreichem Lesevorgang über den Interface Pointer ipDestContainer zu erreichen.

Anwendung

Das Laden eines Containers mit expliziter Typangabe ContainerType_Vector_TcVnPoint2_DINT vom Pfad C:\TcVision\Container.xml sieht z. B. so aus:

fbReadContainer(
    sFilePath       := 'C:\TcVision\Container.xml', 
    ipDestContainer := ipContainer,
    nDestTypeGuid   := ContainerType_Vector_TcVnPoint2_DINT,
    bRead           := TRUE,
    nTimeout        := T#500MS);

IF NOT fbReadContainer.bBusy AND NOT fbReadContainer.bError THEN
    // container is accessible in ipContainer
END_IF

Verwandter Funktionsblock: FB_VN_WriteContainer.

Required License

TC3 Vision Base

System Requirements

Development environment	Target platform	PLC libraries to include
TwinCAT V3.1.4024.59 or later	PC or CX (x64) with PL50, e.g. Intel 4-core Atom CPU	Tc3_Vision