Get_Attribute_Single (FB)¶

FUNCTION_BLOCK Get_Attribute_Single EXTENDS BaseService

Use this function block for querying the attribute of a specific instance of a CIP object.

Note

Data received and send needs to be swapped. See parent folder.

(* CIP Data type for string with a length of max. 64 chars *)
TYPE STRING64 :
STRUCT
   uiLength   : UINT;
   sString    : STRING(63);
END_STRUCT
END_TYPE

PROGRAM PLC_PRG
VAR
    strHostnameToGet   : STRING64;
    getAttributeSingle : ENIP.Get_Attribute_Single ;
    udiReceivedData    : UDINT;
END_VAR

getAttributeSingle(
    xExecute:= ,
    itfEtherNetIPDevice:= EtherNetIP_Adapter,    (* instance of the device (instance is found in the I/O Mapping of the device) *)
    eClass:= ENIP.CIPClass.TCPIPInterfaceObject, (* cip class which contains the desired attribute *)
    dwInstance:= 1,                              (* value of 0 is class level, range from 1..x is instance level *)
    wAttribute:= 6,                              (* attribute no. 6 of the tcp/ip interface object is the Hostname (CIP Spec. Vol.2 Chapter 5-3.3.2.6)*)
    pData:= ADR(strHostnameToGet),               (* data buffer *)
    udiDataSize:= SIZEOF(strHostnameToGet),      (* size of the data buffer *)
    xDone=> ,
    xBusy=> ,
    xError=> ,
    eError=> ,
    udiReceivedDataSize=> udiReceivedData );     (* if the request was successful, udiReceivedData contains the number of bytes which have been received *)
    ;

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.	ETrig
Output	`xDone`	`BOOL`	`TRUE`: Action successfully completed	ETrig
	`xBusy`	`BOOL`	`TRUE`: Function block active	ETrig
	`xError`	`BOOL`	`TRUE`: Error occurred, function block aborts action `FALSE`: No error	ETrig
Input	`itfEtherNetIPDevice`	`IEtherNetIPService`		BaseService
	`eClass`	CIPClass		BaseService
	`dwInstance`	`DWORD`		BaseService
Output	`eError`	ERROR		BaseService
Input	`wAttribute`	`WORD`
	`pData`	POINTER TO BYTE
	`udiDataSize`	`UDINT`
Output	`udiReceivedDataSize`	`UDINT`