Doc.Id. SCM-1200-093
Anybus Communicator for Modbus Plus
Doc.Rev. 3.01
Chapter 6
6. Transactions
6.1 General
As mentioned previously, transactions are representations of the actual serial telegrams exchanged on
the serial subnetwork. While the gateway doesn’t feature a scanlist in the traditional sense, all nodes, and
their transactions, will be processed in the order they have been defined in the Anybus Configuration
Manager.
Transactions are handled slightly differently in the three protocol modes:
• Master Mode
For regular nodes, transactions always come in pairs; a query and a response. The query is issued
by the gateway, while responses are issued by the slaves on the subnetwork. The Broadcaster can
only send transactions.
• Generic Data Mode
Transactions can be added as desired for both directions. Transactions sent to the subnetwork
are called ‘Transaction Produce’, and transactions issued by other nodes are called ‘Transaction
Consume’.
• DF1 Master Mode
Please refer to “DF1 Protocol Mode” on page 51.
Theoretically, the gateway supports up to 150 transactions. The actual number may however be less de-
pending on the memory requirements of the defined transactions.
Summary of Contents for Communicator Modbus plus
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