Instruction manual

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12. Unit Configuration Concepts
12.1 Port and Protocol Configuration
Each of the communication ports (or, in the case of the Ethernet port, the
protocols) can be individually configured or enabled/disabled. It is important to
note that the ports (and Ethernet protocols) function independent of one
another, and can operate simultaneously. For example, a Modbus TCP/IP
request, Modbus RTU slave request on RS485A, and an ASD1 request can
simultaneously
access the same internal point.
Although each communication port can be configured via the web interface,
their configuration selections vary slightly. The Toshiba ASD common serial
ports have a simple enable/disable selection. The RS232 and RS485 ports can
be disabled, or can have one of a selection of control protocols assigned to
them. The Ethernet port can by definition carry multiple control protocols
simultaneously, and therefore each protocol it supports can be individually
enabled or disabled.
Along with the protocol selection for the RS232/RS485 ports, each of these
ports also has a corresponding baudrate, parity, address assignment and
timeout time assignment. Note that not all assignable protocols support the
same range of configuration options: therefore be sure to assign a valid entry in
all cases (for example, a Modbus RTU slave’s “address” assignment must be in
the range 1-247 to comply with the Modbus specification). Also note that
certain protocols may not make use of all available configuration options (e.g.
certain protocols operate only at one specified baudrate regardless of the
“baudrate” selection value). The protocol-specific sections of this manual will
document these cases.
Similarly, each of the Ethernet protocols has its own unique configuration
attributes, such as Ethernet/IP’s assembly object member lists and Modbus
TCP/IP’s timeout assignments.
12.2 Timeout Configuration
The gateway’s points can be configured to perform a specific set of actions
when primary communications are lost on one or more of its various networks.
This allows each point to have its own unique “fail-safe” condition in the event
of a network interruption. There are three separate elements (four in the case
of Modbus TCP/IP) that define the network timeout behavior:
• A port’s network timeout time
• A point’s “Timeout Enable” selection
• A point’s “Timeout Value” setting
• For Modbus TCP/IP, a “Master IP” address designation