Siemens Simatic S7-300 Technical Data Manual page 170

Technical data of CPU 31x
7.2 CPU 312
Technical data
Data areas and their retentivity
Flag bits
•
•
Clock flag bits
Data blocks
•
Local data per priority class
Blocks
Total
OBs
•
Nesting depth
•
•
FBs
•
FCs
•
Address areas (I/O)
Total I/O address area
I/O process image
Digital channels
of those local
Analog channels
of those local
Assembly
Racks
Modules per rack
Number of DP masters
•
•
7-4
Retentive memory
Default retentivity
Length
Length
Per priority class
additional within an error OB
Length
Length
Integrated
Via CP
128 bytes
Yes
MB0 to MB15
8 (1 byte per flag bit)
511
(DB 1 to DB 511)
16 KB
max. 256 bytes
1024 (DBs, FCs, FBs)
The maximum number of blocks that can be
loaded may be reduced if you are using another
MMC.
See the Instruction List
max. 16 KB
8
4
Max. 512
(FB 0 to FB 511)
max. 16 KB
Max. 512
(FC 0 to FC 511
max. 16 KB
1024 bytes /1024 bytes
(can be freely addressed)
128 bytes/128 bytes
Max. 256
Max. 256
Max. 64
Max. 64
Max. 1
Max. 8
None
1
CPU 31xC and CPU 31x, Technical data
Manual, Edition 08/2004, A5E00105475-05