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.

(* 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