Changing Profibus Mode Of The Master Unit - Omron SYSMAC CS Series Operation Manual

Operating the Network
6-6-2

Changing PROFIBUS Mode of the Master Unit

PROFIBUS DP Network
Modes
Normal Operating Modes
Changing the Mode from
the CS1/CJ1W-PRM21
Master DTM
Example
Changing the Mode Using
the PLC Program
The PROFIBUS standard defines four different network modes, in which a
Master Unit can operate. The modes are:
• OFFLINE
The PROFIBUS Master Unit does not access the network, nor does it
respond to messages.
• STOP
The PROFIBUS Master Unit is on-line, but does not communicate with its
slave devices. It does communicate with other Master Units, in that it
passes the token message.
• CLEAR
The PROFIBUS Master Unit is on-line and communicates with its slave
devices. It will parameterize all allocated slave devices, but only read their
input data. The Master Unit does not send valid output data to the slave
devices. Instead it will send empty output data messages or messages
containing zeros.
• OPERATE
The PROFIBUS Master Unit is on-line and communicates with its slave
devices. It will parameterize all allocated slave devices, and exchange all
I/O data for which it has been configured.
The OPERATE mode is the mode used for normal network operation. The
CLEAR mode is the mode used for situations which require a safety state to
fall back to (see section 6-6-4 Using Auto-CLEAR).
In order to change the Unit's operational mode, open the CS1/CJ1W-PRM21
Master DTM Diagnosis User Interface. The figure below shows this Online
Operations tab. Press the desired mode button in the upper left corner of the
window.
In order to change the network to OPERATE mode, i.e. start I/O data
exchange, press the OPERATE button. The OPERATE status of the Master
Unit can be retrieved from the Monitor - Master status tab in the same user
interface.
The Unit's operational mode can also be changed from the PLC user pro-
gram, by setting the appropriate bit in the Software Switches 1 Word (CIO
Word n, see section 4-2-1 Software Switches 1 (Word n)).
Section 6-6
183