Function Blocks And Functions, Data Blocks, Plc Data Types - Siemens SIMATIC S7-300 Manual For Migrating

5 Software Conversion
Overview of organization blocks and their priorities
There are other organization blocks for other tasks. The OBs and their appropriate
priorities are listed in the following table:
Table 5-16
Name of the OB
Startup
Cyclic program
Time-of-day interrupt
Time-delay interrupt
Cyclic interrupt
Hardware interrupt
Status interrupt
Update interrupt
Manufacturer or profile-
specific interrupt
Isochronous interrupt
Time error
Cycle monitoring time
Diagnostic interrupt
Removing/inserting
modules
Module rack error
MC servo interrupt
MC interpolator interrupt
Programming error
I/O access fault
Note The communication always has priority 15. This makes it possible to provide
OBs with a priority larger than 15 so that these OBs are not interrupted by the
communication.
5.3.2

Function blocks and functions, data blocks, PLC data types

For reasons of compatibility STEP 7 V5.x and STEP 7 TIA Portal does not differ in
the basic functions but in some details. They are explained in detail in the
programming guideline.
https://support.industry.siemens.com/cs/ww/en/view/81318674
Migration S7-300/S7-400 nach S7-1500
Entry ID: 109478811, V1.1,
Possible priorities
(preset priorities)
2-24 (8-17, depending on
05/2017
Possible OB numbers
1
1
2 -24 (2)
2-24 (3)
frequency)
2-26 (18)
2-24(4)
2-24(4)
2-24(4)
16-26 (21)
22
22
2-26 (5)
2-26 (6)
2-26(6)
17-26 (25)
16-26 (24)
2-26 (7)
2-26 (7)
100 or 123
1 or 123
10-17 or 123
20-23 or 123
30-38 or 123
40-47 or 123
55
56
57
61-64 or 123
80
80
82
83
86
91
92
121
122
62