Siemens CP 443-1 Manual page 40

5 Performance Data
Notice
The flash area of the file system allows a limited number of write cycles
(approximately 100 000). You should therefore avoid writing data cyclically.
If you are writing temporary data often, you should use the RAM file system
located in the subfolder /ram or /sram. The files of the RAM file system (/ram) are
lost if there is power down.
S RAM area (/ram volatile memory):
In contrast to the flash area, the RAM can be written to and read from any
number of times. The data in the RAM are retained as long as the CP is
supplied with power.
The RAM is intended to store data that change during operation and need to be
recorded (data recording services). The RAM is also suitable for temporary
storage.
The RAM is located in the file system below the "/ram" folder. All files and
folders below this folder are lost when there is a power down.
S Battery Backed RAM Area (/sram − backed by the battery of the power
supply):
The battery backed RAM area can be used in the same way as the volatile
RAM described above. This RAM is located in the file system below the "/sram"
folder.
If you turn off the power or if there is a power down, the stored data is retained.
However, if you remove the module from the rack, this data is also lost since is
backed by the battery of the power supply.
Please remember the following restrictions:
Table 5-8
Characteristic
File Names
File Size
Memory Area for the File System
B4A−40
Explanation / Values
The length of file names is limited to 64 characters for the file name
itself and up to 256 characters for the path.
The file names are case-sensitive.
The file size is limited to a maximum of 8 MB.
− Flash area (non-volatile memory)
30 MB
− RAM area (volatile memory)
16 MB
− RAM (SRAM) − backed by the battery of the power supply
module
512 Kbytes
CP 443-1 Advanced for Industrial Ethernet / Manual Part B4A
Release 01/2007
C79000-G8976-C193-06