Appendix 
  A.1 Information about upgrading to a CPU 31xC or CPU 31x 
CPU 31xC and CPU 31x, Technical Data 
Manual, 01/2006 Edition, A5E00105475-06 
A-7 
A.1.9  Load memory concept for the CPU 31xC/31x 
Load memory concept for the CPU 31xC/31x 
On CPUs 312 IFM to 318-2 DP, the load memory is integrated into the CPU and may be 
extended with a memory card, 
The load memory of the CPU 31xC/31x is located on the micro memory card (MMC), and is 
retentive. When blocks are downloaded to the CPU, they are stored on the MMC and cannot 
be lost even in the event of a power failure or memory reset. 
Reference 
See also the 
Memory concept 
chapter in the 
CPU Data 31xC and 31x manual.
 
 
 
 
Note 
User programs can only be downloaded and thus the CPU can only be used if the MMC is 
inserted. 
 
A.1.10  PG/OP functions 
PG/OP functions 
With CPUs 315-2 DP (6ES7315-2AFx3-0AB0), 316-2DP and 318-2 DP, PG/OP functions at 
the DP interface were only possible if the interface was set to active. With CPUs 31xC/31x, 
these functions are possible at both active and passive interfaces. The performance of the 
passive interface is considerably lower, however. 
A.1.11  Routing for the CPU 31xC/31x as an intelligent slave 
Routing for the CPU 31xC/31x as an intelligent slave 
If you use the CPU 31xC/31x as an intelligent slave, the routing function can only be used 
with an actively-configured DP interface.  
In the properties of the DP interface in STEP 7, select the "Test, Commissioning, Routing" 
check box of the "DP-Slave" option.