Memory concept   
4.2 Memory functions 
  CPU 31xC and CPU 31x, Technical Data 
4-18  Manual, 01/2006 Edition, A5E00105475-06 
4.2.7  Backup of project data to SIMATIC Micro Memory Card (MMC) 
Function principle 
Using the Save project to Memory Card and Fetch project from Memory Card functions, you 
can save all project data to a SIMATIC Micro Memory Card, and retrieve these at a later 
time. For this operation, the SIMATIC Micro Memory Card can be located in a CPU or in the 
MMC adapter of a PG or PC.  
Project data are compressed before they are saved to a SIMATIC Micro Memory Card, and 
uncompressed when fetched.  
 
 
Note 
In addition to project data, you may also have to store your user data on the MMC. You 
should therefore first verify SIMATIC Micro Memory Card memory space.  
A message warns you if the memory capacity on your SIMATIC Micro Memory Card is 
insufficient 
 
The volume of project data to be saved corresponds with the size of the project's archive file.  
 
 
Note 
For technical reasons, you can only transfer the entire contents (user program and project 
data) using the Save project to memory card action.