MVI56E-FLN ♦ ControlLogix Platform
Reference
FA Control Network Ethernet Communication Module
User Manual
ProSoft Technology, Inc.
Page 123 of 155
4.4.8 Network Management
Nodes can be added while the FL-net system is running.
The system will continue to run even if any node fails.
Each node knows the state of all the other nodes.
Each node manages In-ring and Out-ring of nodes
One token is circulated between all nodes in the FL-net and the token is
monitored by the time of each node. If a node does not send the token, the
next node will reissue it after a fixed time interval.
Out-ring management
If a node does not send the token, every node will recognize the node failure.
In-ring management
New node sends a participation request frame and every node monitors it.
Node state management
Network status and upper layer status are attached in the cyclic frame.
4.4.9 Masterless Transmission Management
Token
1
A node can transmit data only while holding a token, with the following two
exceptions:
Reissue of token due to failure of a node to send a token within the token
monitoring time
Transmission of participation request frame when the node has not joined in
the network
1
A single token is circulated among nodes. A node receiving a token holds the
transmission right until it releases the token to the next node.
2
The token is circulated between all the nodes joining the FL-net.
3
The token can be transmitted along with cyclic data.
4
The token can also be circulated without any data.
5
The token is monitored by each node's timer. If the token is not released by a
node within a fixed time, the token is automatically reissued.
6
If there are two tokens in the network, they are combined into one.
