DataFileCopy: Copy File Commands

Function Block Description

This function block copies memory data to a file and vice versa. The file is located either within the internal file system or an external file system (SD card).

The DataFileCopy function block can:

oRead data from a formatted file or

oCopy data from memory to a formatted file. For further information, refer to Flash Memory Organization.

Graphical Representation

IL and ST Representation

To see the general representation in IL or ST language, refer to the chapter Function and Function Block Representation.

I/O Variable Description

This table describes the input variables:

Input	Type	Comment
xExecute	BOOL	On rising edge, starts the function block execution. On falling edge, resets the outputs of the function block when any ongoing execution terminates.
sFileName	STRING	File name without extension (the extension .DTA is automatically added). Use only a...z, A...Z, 0...9 alphanumeric characters.
xRead	BOOL	TRUE: copy data from the file identified by sFileName to the internal memory of the controller. FALSE: copy data from the internal memory of the controller to the file identified by sFileName.
xSecure	BOOL	TRUE: The MAC address is always stored in the file. Only a controller with the same MAC address can read from the file. FALSE: Another controller with the same type of memory can read from the file.
iLocation	INT	0: the file location is /usr/DTA in internal file system. 1: the file location is /usr/DTA in external file system (SD card). NOTE: If the file does not already exist in the directory, the file is created.
uiSize	UINT	Indicates the size in bytes. Maximum is 65534 bytes. Only use addresses of variables conforming to IEC 61131-3 (variables, arrays, structures), for example: Variable : int; uiSize := SIZEOF (Variable);
dwAdd	DWORD	Indicates the address in the memory that the function will read from or write to. Only use addresses of variables conforming to IEC 61131-3 (variables, arrays, structures), for example: Variable : int; dwAdd := ADR (Variable);

WARNING

UNINTENDED EQUIPMENT OPERATION

Verify that the memory location is of the correct size and the file is of the correct type before copying the file to memory.

Failure to follow these instructions can result in death, serious injury, or equipment damage.

This table describes the output variables:

Output	Type	Comment
xDone	BOOL	TRUE = indicates that the action is successfully completed.
xBusy	BOOL	TRUE = indicates that the function block is running.
xError	BOOL	TRUE = indicates that an error is detected and the function block aborted the action.
eError	DataFileCopyError	Indicates the type of the data file copy detected error.

NOTE: If you write to memory variable within the area of the file write, a CRC integrity error results.

Example

This example describes how to copy file commands:

VAR
LocalArray : ARRAY [0..29] OF BYTE;
myFileName: STRING := 'exportfile';
EXEC_FLAG: BOOL;
DataFileCopy: DataFileCopy;
END_VAR
DataFileCopy(
xExecute:= EXEC_FLAG,
sFileName:= myFileName,
xRead:= FALSE,
xSecure:= FALSE,
iLocation:= DFCL_INTERNAL,
uiSize:= SIZEOF(LocalArray),
dwAdd:= ADR(LocalArray),
xDone=> ,
xBusy=> ,
xError=> ,
eError=> );