Siemens Simantic ET200SP - Basics of program execution; Events and OBs

Distributed I/O system
150 System Manual, 12/2016, A5E03576849-AG
Basics of program execution
7
7.1
Events and OBs
Response to triggers
The occurrence of a start event results in the following reaction:
● If the event comes from an event source to which you have assigned an OB, this event
triggers the execution of the assigned OB. The event is positioned in a queue according
to its priority.
● If the event comes from an event source to which you have not assigned an OB, the CPU
executes the default system reaction.
Note
Some event sources, such as startup, pull/plug, exist even if you do not configure them.
The table below provides an overview of the start events, including the possible values for
OB priority, possible OB numbers, default system reaction and number of OBs. The table is
sorted in ascending order by OB numbers.
Types of event sources
Possible priorities (default
priority)
Possible OB num-
bers
Default system
response
1)
Number of OBs
Starting
2)
1
100, ≥ 123
Ignore
0 to 100
Cyclic program
2)
1
1, ≥ 123
Ignore
0 to 100
Time-of-day interrupt
2)
2 to 24 (2)
10 to 17, ≥ 123
Not applicable
0 to 20
Time-delay interrupt
2)
2 to 24 (3)
20 to 23, ≥ 123
Not applicable
0 to 20
Cyclic interrupt
2)
2 to 24 (8 to 17, frequency
dependent)
30 to 38, ≥ 123 Not applicable 0 to 20
Hardware interrupt
2)
2 to 26 (18)
40 to 47, ≥ 123
Ignore
0 to 50
Status interrupt
2 to 24 (4)
55
Ignore
0 or 1
Update interrupt
2 to 24 (4)
56
Ignore
0 or 1
Manufacturer-specific or
profile-specific interrupt
2 to 24 (4) 57 Ignore 0 or 1
Synchronous cycle interrupt
16 to 26 (21)
61 to 64, ≥ 123
Ignore
0 to 2
Time error
3)
22 80
Ignore
0 or 1
Cycle monitoring time ex-
ceeded once
STOP
Diagnostics interrupt
2 to 26 (5)
82
Ignore
0 or 1
Pull/plug interrupt for mod-
ules
2 to 26 (6) 83 Ignore 0 or 1
Rack error 2 to 26 (6) 86 Ignore 0 or 1
MC-servo
4)
17 to 26 (25)
91
Not applicable
0 or 1