UA_MethodCall

This function block calls a method on a remote UA Server. The method is determined by a connection and a method handle. The former can be queried by UA_Connect, the latter by UA_MethodGetHandle.

Inputs

VAR_INPUT
    Execute                     : BOOL;
    ConnectionHdl               : DWORD;
    MethodHdl                   : DWORD;
    nNumberOfInputArguments     : UDINT;
    pInputArgInfo               : POINTER TO ST_UAMethodArgInfo;
    cbInputArgInfo              : UDINT;
    pInputArgData               : PVOID;
    cbInputArgData              : UDINT;
    pInputWriteData             : PVOID;
    cbInputWriteData            : UDINT;
    nNumberOfOutputArguments    : UDINT;
    pOutputArgInfo              : POINTER TO ST_UAMethodArgInfo;
    cbOutputArgInfo             : UDINT; 
    pOutputArgInfoAndData       : PVOID;
    cbOutputArgInfoAndData      : UDINT; 
    Timeout                     : TIME := DEFAULT_ADS_TIMEOUT; 
END_VAR

Name	Type	Description
Execute	BOOL	The command is triggered by a rising edge at this input.
ConnectionHdl	DWORD	Connection handle previously output by the function block UA_Connect.
MethodHdl	DWORD	Method handle, previously output by the function block UA_MethodGetHandle.
nNumberOfInputArguments	UDINT	Number of input parameters.
pInputArgInfo	POINTER TO ST_UAMethodArgInfo	Points to the buffer address where input parameter information is stored in the form of an array ST_UAMethodArgInfo.
cbInputArgInfo	UDINT	Size of the buffer where the input parameter information is stored.
pInputArgData	PVOID	Points to the buffer address where input parameters (constant length) are stored.
cbInputArgData	UDINT	Size of the input buffer where input parameters (with constant length) are stored.
pInputWriteData	PVOID	Pointer to buffer address where input parameters (dynamic length) are stored.
cbInputWriteData	UDINT	Size of the input buffer where input parameters (with dynamic length) are stored.
nNumberOfOutputArguments	UDINT	Number of output parameters.
pOutputArgInfo	POINTER TO ST_UAMethodArgInfo	Points to the buffer address where output parameter information is stored as array ST_UAMethodArgInfo. nLenData is required to determine the target memory of the individual output parameters. The other elements can be set in such a way that a type check of the returned parameters takes place or remains undefined.
cbOutputArgInfo	UDINT	Size of the buffer where the output parameter information is stored.
pOutputArgInfoAndData	PVOID	Points to the buffer address where the output parameters are to be saved as a BYTE array. The BYTE array contains the number of output parameters as DINT, four reserved bytes and parameter information as ARRAY OF ST_UAMethodArgInfo (with the length of the output parameters), followed by pure data. Note that the data is packed as 1-byte alignment.
cbOutputArgInfoAndData	UDINT	Size of the buffer in which the output parameters are to be saved as a BYTE array.
Timeout	TIME	Time until the function is aborted. DEFAULT_ADS_TIMEOUT is a global constant, set to 5 seconds.

Outputs

VAR_OUTPUT
    cbRead_R     : UDINT;
    Done         : BOOL;
    Busy         : BOOL;
    Error        : BOOL;
    ErrorID      : UDINT;
END_VAR

Name	Type	Description
cbRead_R	UDINT	Counts all the bytes received.
Done	BOOL	Switches to TRUE if the function block was executed successfully.
Busy	BOOL	TRUE until the function block has executed a command, at the most for the duration of the "Timeout" at the input. The inputs accept no new command as long as Busy = TRUE. It is not the connection time that is monitored but the reception time.
Error	BOOL	Switches to TRUE if an error occurs while executing a command. The command-specific error code is contained in nErrID.
ErrorID	UDINT	Contains the command-specific error code of the most recently executed command.

Requirements

Development environment	Target platform	PLC libraries to include
TwinCAT 3.1	Win32, Win64, CE-X86, CE-Arm®	Tc3_PLCopen_OpcUa