Functionalities¶
Note
The maximum number of files opened at the same time is limited to 1007.
The max. length of the user string (path and filename) is 241 characters.
| Component | As of CPU firmware | Functionality |
|---|---|---|
| RAM disk | V2.0.2 | Load / save boot project Firmware update Internal system files |
| V2.1.3 | Files via FTP server (e. g. firmware update) | |
| User disk | V2.0.2 | WEB visu files and JAVA applet for webserver Symbol file for OPC server and CP600 panels |
| V2.1.3 | JAVA script files for webserver User data via CAA_File_xxx.lib CAA_File_Library: CAA_File Library Files via FTP server |
|
| SRAM disk | V2.1.3 | User data via CAA_File_xxx.lib CAA_File_Library: CAA_File Library Files via FTP server |
| Internal flash | V2.0.2 | CPU firmware Traceability and configuration data User application: boot project, symbol file and WEB visu files (BOOT.ZIP + WEBVISU.ZIP) User data via Internal System Library: Internal System Library |
| Flash disk | V2.1.3 | User data via CAA_File_xxx.lib CAA_File_Library: CAA_File Library Files via FTP server |
| SD memory card (removable) | V2.0.2 | Firmware update Load / save boot project Source code of user project load / save User data via POUs SD_WRITE: SD_WRITESD_READ: SD_READ Retain data Persistent data |
| V2.1.3 | User data via CAA_File_xxx.lib CAA_File_Library: CAA_File Library Files via FTP server |
Note
Unlike the PLC’s memory areas like %M or Retain, where 1 byte actually consumes 1 byte, all storage device utilize a file system.
That means there is a difference between a files size and its size on the disk.
On disks the files are stored in so-called clusters which are a group of disk sectors. “Size on disk” refers to the amount of cluster(s) a file is taking up, while “file size” is an actual byte count of the file data. So you will usually find that the size on disk is larger than the file size. This is not an error, but a result of the disk organization via a file system. Since sector and cluster sizes vary depending on a disk’s size and the used file system, the ratios between the size on disk and the file size also vary between the various storage devices.