fsMediaWriteProtected (Function)

This queries if a media is write protected. If the media is write protected, it is not possible to write any information to it (read-only mode), and it is not possible to create, modify, or delete any files or directories.

The write protection on an SD-CARD is determined by the small "tab" on the edge of the card.

This "tab" is only present on the full-size SD-CARD - therefore devices with a micro-SD-CARD reader will never report the media as write protected.

USB medias can be write protected for multiple reasons, including by setting physical write protection switches or, especially in the case of flash medias, in the case of errors on the file system.

Input:

media : INT (0..3)

The media to query.

Returns: BOOL

Declaration:

FUNCTION fsMediaWriteProtected : BOOL;
VAR_INPUT
   media : INT;
END_VAR;

Example:

INCLUDE rtcu.inc
 
PROGRAM FileExample;
VAR
   mediaPresent : BOOL;
   rc           : INT;
END_VAR;
 
fsMediaOpen(media := 0);
 
BEGIN
   // Update media status
   IF mediaPresent <> fsMediaPresent(media := 0) THEN
      IF fsMediaPresent(media := 0) THEN
         IF fsMediaWriteProtected(media := 0) THEN
            DebugMsg(message := "Media present, media write protected!");
         END_IF;
         // Open files
         ...
      ELSE
         DebugMsg(message := "Media has been removed!");
      END_IF;
      // Save current status
      mediaPresent := fsMediaPresent(media := 0);
   END_IF;
   ...
END;
 
END_PROGRAM;