Siemens Simatic S7-300 CPU 31xC and CPU 31x S7-300 - Manual (Page 114)

Technical data of CPU 31xC
6.2 CPU 312C
CPU 31xC and CPU 31x, Technical data
6-4
Manual, Edition 08/2004, A5E00105475-05
Technical data
IEC Timers
Yes
• Type SFB
• Number unlimited (limited only by RAM size)
Data areas and their retentivity
Flag bits
128 bytes
• Retentive memory Configurable
• Default retentivity MB0 to MB15
Clock flag bits 8 (1 byte per flag bit)
Data blocks Max. 511
(DB 1 to DB 511)
• Length max. 16 KB
Local data per priority class max. 256 bytes
Blocks
Total
1024 (DBs, FCs, FBs)
The maximum number of blocks that can be
loaded may be reduced if you are using another
MMC.
OBs see the Instruction List
• Length max. 16 KB
Nesting depth
• Per priority class 8
• additional within an error OB 4
FBs Max. 512
(FB 0 to FB 511)
• Length max. 16 KB
FCs Max. 512
(FC 0 to FC 511)
• Length max. 16 KB
Address areas (I/O)
Total I/O address area
max. 1024 bytes/1024 bytes
(can be freely addressed)
I/O process image 128 bytes/128 bytes
Digital channels Max. 256
• of those local Max. 256
• Integrated channels 10 DI / 6 DO
Analog channels Max. 64
• of those local Max. 64
• Integrated channels None