Siemens DP/AS-Interface Link 20E, Руководство пользователя

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Using the Command Interface
92
DP/AS-Interface Link 20E
Release 11/2002
C79000-G8976-C138–04
3.3.11 Set_Offline_Mode
Purpose
This call switches between the online and offline mode.
The online mode is the normal operating situation for the AS-i master. Here, the
following jobs are processed cyclically:
S
During the data exchange phase, the fields of the output data are transferred to
the slave outputs for all AS-i slaves in the LAS. The addressed AS-i slaves
transfer the values of the slave inputs to the master when the transfer was free
of errors.
S
This is followed by the inclusion phase in which there is a search for the existing
AS-i slaves and newly added AS-i slaves are entered in the LDS or LAS.
S
In the management phase, jobs from the user such as writing parameters are
executed.
In the offline mode, the DP/AS-i Link 20E only processes jobs from the user.
(Jobs that involve the immediate addressing of an AS-i slave are rejected with an
error.) There is no cyclic data exchange with the AS-i slaves.
The OFFLINE=TRUE bit is not permanently stored; in other words, following a
cold/warm restart, the DP/AS-i Link 20E is once again in the online mode.
Structure of the Job Data in the Send Buffer
Byte Meaning
Bit 7 Bit 1 Bit 0
0 Command number: 0A
H
1 reserved Mode
(0=online
1=offline)