5-12SectionK: Connection Information
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The base node is the node that reads the connection mode and network par-
ticipation status, and checks the integrity of the connection order read from
the nodes.
The base node is specified as the “Nd# order” when the nodes are displayed
in connection order. When connection information is displayed for the first
time, the base node is the node to which the Controller Link Support Soft-
ware is connected.
2. Reading the Network Participation Status from the Base Node
This is performed by sending the CONTROLLER STATUS READ com-
mand. The nodes that are participating in the network are identified from this
information, and a Network Participation List is created. When reading
information from “all” nodes, reading is, in fact, executed only for nodes that
are registered on this list.
3. Reading Information from All Nodes
This is performed by sending the CONNECTION DATA READ, NETWORK
DISCONNECT DATA READ, and CONTROLLER DATA READ commands.
All the information required for the Network Configuration Screens is read.
Screen Display when Information is not Concurrent
While a node is participating in a Controller Link Network, its network participa-
tion status is constantly being updated. If the network is in token ring mode and
there is a normal ring connection status, the connection information, along with
the time at which it was created, is updated with every communications cycle. If
the ring becomes disconnected, the information updated immediately before the
disconnection will be maintained. If there is disconnection in only one place,
information can still be read in the normal way, but if a node is separated or
added during disconnection, the information will not be concurrent.
•Non-participating Nodes
A non-participating node is a node that is not in the Network Participation List,
but is in the connection order information for the base node. This kind of node
was separated from the network after the connection information for the base
node had been created. “Read error” will be displayed in “Start time of mea-
sure” for any such node. Information will not be read for any non-participating
nodes, and there will be nothing displayed for any of the information items.
When a Network Configuration Screen is displayed in connection order, the
node will be displayed according to the order recorded in the base node. This
situation is caused in token ring mode by a node leaving the network while the
line is disconnected.
•Logical Error
A logical error will occur when a there is a node that is in the Network Participa-
tion List, but not in the connection order information for the base node. This
kind of node entered the network after the connection information for the base
node has been created. The node address of any node with a logical error will
be displayed with a “#” sign attached to it. Because it exists in the Network Par-
ticipation List, all information is displayed. When a Network Configuration
Screen is displayed in connection order, the order of connection is unclear, so
the node will be displayed at the end (with no color differentiation for SL1 and
SL2). This situation is caused in token ring mode by a node joining the network
while the line is disconnected.
•Verify Error
A verify error will occur when there is a node that is in the Network Participation
List and in the connection order information for the base node but for which
there is a discrepancy in the connection order information. The node address
for any node with a verify error will be displayed with an asterisk. All information
is displayed, and the information on a Network Configuration Screen will be
displayed in the connection order recorded in the base node. SL1 and SL2,