Anybus Communicator Modbus plus, Руководство пользователя

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Transactions 36
Doc.Id. SCM-1200-093
Anybus Communicator for Modbus Plus
Doc.Rev. 3.01
6.3.2 Parameters (Response)
(To gain access to these parameters, select a Response-transaction in the Navigation Section)
6.4 Transaction Parameters (Generic Data Mode)
6.4.1 Produce-Transactions
(To gain access to these parameters, select a Produce Transaction in the Navigation Section)
Parameter Description
Trigger byte This parameter is used to enable/disable the trigger functionality for the response. If
enabled, the gateway will increase the trigger byte by one when the gateway receives new
data from the subnetwork. This can be used to notify the control system of the updated
data.
The location of the trigger byte is specified by the ‘Trigger byte address’ parameter below.
Trigger byte address This parameter specifies the location of the trigger byte in the internal memory buffer.
Valid settings range from 0x000... 0x1FF and 0x400... 0xNNN
Parameter Description
Offline options for fieldbus This parameter specifies the action to take for this transaction if the higher level network
goes offline. This affects the data that is sent to the subnetwork.
• Clear
Data is cleared (0) on the subnetwork if the higher level network goes offline
• Freeze
Data is frozen on the subnetwork if the higher level network goes offline
• NoScanning
Stop subnet scanning for this transaction if the higher level network goes offline
Update mode The update mode for the transaction:
• Cyclically
The transaction is sent cyclically at the interval specified in the ‘Update Time’-param-
eter.
• On data change
The data area is polled for changes at the time interval defined by Update time. A
transaction is issued when a change in data is detected.
• Single shot
The transaction is sent once at startup.
• Change of state on trigger
The transaction is sent when the trigger byte has changed. This feature enables the
control system to notify the gateway when to issue a particular transaction. To use this
feature correctly, the control system must first update the data area associated with
the transaction, then increase the trigger byte by one. The location of the trigger byte
is specified by the ‘Trigger byte address’ parameter.
Update time (10 ms) This parameter specifies how often the transaction will be issued in steps of 10ms (only
relevant when ‘Update mode’ is set to ‘Cyclically’).
The entered value is multiplied by 10. For instance, an entered value of 5 results in 50 ms.