5 USER GUIDE
5-11
(2) FL-net protocol
The FL-net consists of six protocol layers as shown in Figure 5-9.
The transport layer and network layer use UDP/IP, whereas the data link layer and physical
layer use Ethernet.
Application layer
Controller interface
Service function
Cyclic
transmission Message transmission
FA link protocol layer
Token function
Transport layer
UDP
Network layer
IP
Data link layer
Physical layer
Ethernet
(IEEE 802.3-compliant)
Figure 5-9 FA Link Protocol
(3) FL-net transmission system features
The features of the FL-net FA link protocol layer are outlined below:
• Masterless, token-based transmission management is exercised to avoid collisions.
• A token can be circulated at fixed intervals to define the refresh cycle time.
• A predetermined token is transmitted together with cyclic data.
• At startup, a token is transmitted from a node having the lowest node number.
• If a token is not transmitted for a predetermined period of time, the next node transmits a
node.
• Thanks to the use of a masterless, token-based system, network inoperativeness can be
avoided even when some nodes become faulty.
• Operating mode (RUN/STOP), hardware error (ALARM), and other information management
tables are available for referencing the operating status of the other nodes.
FL-net
protocol
Summary of Contents for FL.NET
Page 1: ......
Page 2: ......
Page 29: ...1 OVERVIEW ...
Page 33: ...2 FL NET MODULE ...
Page 42: ...3 FL NET MODULE INSTALLATION ...
Page 46: ...4 FL NET MODULE WIRING PROCEDURES ...
Page 53: ...5 USER GUIDE ...
Page 203: ...5 USER GUIDE 5 151 Sample printout ...
Page 206: ...6 MAINTENANCE ...
Page 210: ...7 TROUBLESHOOTING ...
Page 225: ...8 APPENDIXES ...