FB_FileGets 1:

The function block reads strings from a file. The string is read up to and including the line feed character, or up to the end of the file or the maximum permitted length of sLine. The zero termination is appended automatically. The file must have been opened in text mode.


    sNetId    : T_AmsNetId;
    hFile     : UINT;
    bExecute  : BOOL;
    tTimeout  : TIME := DEFAULT_ADS_TIMEOUT;

sNetId: String containing the AMS network identifier of the target device to which the ADS command is directed (type: T_AmsNetId).

hFile: File handle, which was generated when the function block FB_FileOpen was created.

bExecute: The function block is activated by a rising edge at this input.

tTimeout: States the length of the timeout that may not be exceeded by execution of the ADS command.


    bBusy   : BOOL;
    bError  : BOOL;
    nErrId  : UDINT;
    sLine   : T_MaxString;
    bEOF    : BOOL;

bBusy: When the function block is activated, this output is set to TRUE and remains set until feedback is received. As long as bBusy is TRUE, no new command can be executed.

bError: If an error occurs during command execution, this output is set, once the bBusy output has been reset.

nErrId: Returns the ADS error code or the command-specific error code when the bError output is set.

sLine: String that was read (type: T_MaxString).

bEOF: This output is set if the end of the file was reached and no further data bytes could be read (cbRead=0). This output is not set if further data bytes could be read (cbRead>0).

Command-specific error code

Possible cause


Invalid or unknown file handle.


No memory for read buffer.


File was opened with wrong method (e.g. with obsolete FILEOPEN function block).

Example of calling the function block in FBD:

    fbFileGets        : FB_FileGets;
    hFile             : UINT;
    bFileGets         : BOOL;
    bFileGetsBusy     : BOOL;
    bFileGetsError    : BOOL;
    nFileGetsErrorId  : UDINT;
    strBuffer         : STRING;
    bFileGetsEOF      : BOOL;
FB_FileGets 2:


Development environment

Target system type

PLC libraries to include (Category group)

TwinCAT v3.1.0

PC or CX (x86, x64, ARM)

Tc2_System (System)