Technical data of CPU 31xC   
6.1 General technical data 
  CPU 31xC and CPU 31x, Technical Data 
6-2  Manual, 01/2006 Edition, A5E00105475-06 
6.1.2  Technical specifications of the Micro Memory Card (MMC) 
Plug-in SIMATIC Micro Memory Card (MMC)  
The following memory modules are available: 
Table 6-1  Available SIMATIC Micro Memory Cards 
Type  Order number  Required for a firmware update via  
SIMATIC Micro Memory Card 
MMC 64k  6ES7 953-8LFxx-0AA0  –  
MMC 128k  6ES7 953-8LGxx-0AA0  –  
MMC 512k  6ES7 953-8LJxx-0AA0  –  
MMC 2M  6ES7 953-8LLxx-0AA0  Minimum requirement for CPUs without DP interface 
MMC 4M  6ES7 953-8LMxx-0AA0  Minimum requirement for CPUs without DP interface 
(except CPU 319) 
MMC 8M 
1
  6ES7 953-8LPxx-0AA0  Minimum requirements for the CPU 319 
1
 If you plug in the CPU 312C or CPU 312, you cannot use this SIMATIC Micro Memory 
Card. 
Maximum number of loadable blocks on the SIMATIC Micro Memory Card 
Number of blocks that can be stored on the SIMATIC Micro Memory Card depends on the 
capacity of the SIMATIC Micro Memory Card being used The maximum number of blocks 
that can be loaded is therefore limited by the capacity of your MMC (including blocks 
generated with the "CREATE DB" SFC) 
Table 6-2  Maximum number of loadable blocks on the SIMATIC Micro Memory Card 
Size of SIMATIC Micro Memory 
Card 
Maximum number of blocks that can be loaded 
64 KB  768 
128 KB  1024 
512 KB 
2 MB 
4 MB 
8 MB 
Here the maximum number of blocks that can be loaded for 
the specific CPU is less than the number of blocks that can be 
stored on the SIMATIC Micro Memory Card. 
Refer to the corresponding specifications of a specific CPU to 
determine the maximum number of blocks that can be loaded.