Instructions

Basic Operation 21
Doc: HMSI-27-314, Rev. 3.10Anybus Communicator EtherNet/IP / Modbus-TCP User Manual
2.3.3 Master Mode
In this mode, the communication is based on a query-response scheme; when the gateway issues a query
on the sub-network, the addressed node is expected to issue a response. Nodes are not permitted to issue
responses/messages spontaneously, i.e. without first receiving a query.
There is, however, one exception to this rule; the broadcaster. Most protocols offer some way of broad-
casting messages to all nodes on the network, without expecting them to respond to the broadcasted
message. This is also reflected in the gateway, which features a dedicated broadcaster node.
In Master Mode, Anybus Configuration Manager comes pre-loaded with the most commonly used
Modbus RTU commands, which can be conveniently reached by right-clicking on a node in the Anybus
Configuration Manager and selecting ‘Insert New Command’. Note, however, that this in no way
prevents other protocols based on the same query-response message-scheme from also being imple-
mented.
Subnetwork Devices
Gateway
Control System