Bristol Babcock Network 3000 Setup Manual page 10

Chapter 1 - Introduction
more levels. A BSAP network can support up to six levels (not including the
Network Master referred to as level 0.) The number of levels required varies
depending upon the size and scope of your project. Each controller is assigned an
address to allow data to be routed correctly. Addresses and network structure are
specified using either the Network Topology (NETTOP) Program or the Open
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BSI NetView program. The network information stored internally by a node is
called its Node Routing Table, and is updated whenever an ACCOL load is
downloaded, or a valid time synchronization message is sent.
The level of a given controller specifies how many intervening communication
lines there are between it, and the network master. The first level controllers are
called top-level nodes because data must travel over only 1 communication line to
reach the Network Master. A communication line can consist of a direct cable
connection, a radio or satellite link, or a dial-up modem connection. Each
communication line is configured independently with its own baud rate, poll
period, timeout, etc.
Each controller (node) serves as a master to the nodes connected to it on the level
immediately below, and as a slave to the node connected to it on the level
immediately above. A node can have many slaves but only one master. Each master
polls its slaves for data, which it retains in memory until it is polled by its master.
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The choice of whether NETTOP or NetView is used to configure your network depends on the
software in your system. If you are using DOS-based ACCOL Tools (AIC, ABC, etc.), or Open BSI
Utilities versions lower than 3.0, then NETTOP must be used. If you have Open BSI Utilities 3.0 (or
newer) then NetView must be used. If you want to use a mixture of older DOS-based ACCOL Tools
with Open BSI 3.1 (or newer) you will need to use NetView, and then use the NETBCX utility to
generate network files compatible with the DOS-based tools.
Page 1-2 Network 3000 Communications Configuration Guide