The Network View displays all the communication networks that are part of the workspace (see Figure 8.1b). It organizes the communication networks in a graphical hierarchical tree format. The workspace is the root node of this tree and the physical networks it contains are its first-level sub-nodes. Each physical network can have a list of entries representing logical networks (i.e., communication protocols) that execute over the physical network. Each logical network in turn can have a list of entries representing device network interfaces (e.g., control station, PC, etc.) that communicate over the channel. Each device network interface in turn can have list entries representing the signals that the device is to transmit on the associated network.
For example, the workspace shown in Figure 8.1b contains three RS-485 physical networks named: External Display, HMINet, and Motor Starter. Each physical network has a single logical network associated with it. A custom ASCII protocol is used on the External Display physical network; the FairNET protocol is employed on HMINet; and the Modbus protocol is used in the Motor Starter network. Although RS-485 based physical networks may only have a single logical network attached to them, other physical network channels (e.g., Ethernet) may have multiple logical networks attached (i.e., multiple protocols may execute over the same channel).
Six devices are part of the FairNET logical network executing on the HMINet physical network. Five of these six devices are Chameleon RS-485 Network Interface Modules (NIM-1) configured to execute the FairNET protocol. The other device is a PC equipped with an RS-485 port and the FairNET OPC Server gateway software. In Figure 8.1b, the first device network interface on the HMINet : FairNET network (labeled 1 AMR.NIM.RS485) will source 24 signals. Five of the signals are discrete values and nineteen are analog values.
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Physical Network |
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Logical Network |
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Network Interface (Chameleon Module) |
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Network Interface (FAC-2100 Controller) |
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Network Interface (OPC Server / PC) |
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Analog Signal |
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Discrete Signal |
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Mixed Signal (e.g., ASCII string, data structure, etc.) |
Figure 8.5. Workspace Network-View Icons.
Each item in the Network View pane has descriptive text alongside a small graphic that indicates the type of entry it is. Figure 8.5 lists the network view entries and associated graphic icons.
The next section in this bulletin describes how to add and configure networks to the workspace and how to associate schemas, HMI documents, and OPC servers with each network.
