Siemens IM 151-7 - Overview of the Blocks; IM 151-7 Cpu

Functions of the IM 151-7 CPU
8-42
ET 200S IM 151-7 CPU Interface Module
A5E00058783-04
8.11 Blocks
This section provides an overview of the blocks that run in the IM 151-7 CPU.
The operating system is designed for event-driven processing of the user program.
The following tables show which organization blocks (OBs) the operating system
automatically invokes in response to which events.
More information
You will find a detailed description of the blocks in the
System and Standard Functions Reference Manual. There is an overview of all the
STEP 7 documentation in the ET 200S Distributed I/O System manual.
Overview of all the blocks
Table 8-16 Overview of the blocks
Block
Number Area Maximum size Remarks
OB 17 – 16 kB All the possible OBs are found in the
Instruction list.
FC 512 0-511 –
FB 512 0-511 –
DB 511 1-511 0 is reserved
SFC 61 –
–
All SFCs for the CPU are found in the
Instruction list.
SFB 11 –
–
All SFBs for the CPU are found in the
Instruction list.
A maximum of 1024 blocks (number of FBs + FCs + DBs) can be loaded in each
IM 151-7 CPU.