The term “server” is often used to describe the Modbus TCP version of a Modbus slave. A server will
provide data when a client asks for it. The concept of master/slave is less significant in Modbus TCP
because any TCP device can be both master and slave at the same time, and there can be multiple
“masters” on the network. That is in contrast with Modbus RTU where there can be only one master and
multiple slaves, and each device must be one or the other.
The Modbus TCP server is simply a collection of registers that may contain data. The source of that data in
the case of Babel Buster BB2-7010 can be any of several possible sources. It may be read from another
Modbus device. Another Modbus device could have put it there by writing to the BB2-7010. The data could
have been received by the BACnet client or BACnet server.
9.1 Modbus TCP Device Configuration
The only local device configuration required for Modbus TCP is to set the IP address of the local device.
The standard port for Modbus TCP is 502. This can be changed if necessary.
9. Configuring BB2-7010 as a Modbus TCP Slave
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