Chapter 7: Computer Link Function
(2)
The
Application layer |
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| Cyclic transfer | Service function |
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FA link protocol layer |
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| Message transfer |
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| Token function |
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| protocol |
Transport layer |
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| UDP |
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Network layer |
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| IP |
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Data link layer |
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| Ethernet |
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| (Compatible with IEEE802.3) |
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Physical layer |
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FA link protocol
Note: The transport layer and network layer use the UDP/IP addressing scheme. The data link layer and physical layer use the Ethernet scheme.
(3) Features of the | 7 |
The |
1It manages the transmission of data using the
2It is possible to specify a certain refresh cycle interval as the
3 The specified Token is transmitted together with the cyclic data.
4 When starting up, the
5 When a token is not received within a certain interval, the next node sends a token.
6 By using the
operating.
7 The
STOP) / hardware error (ALARM), so that it can inform other nodes of the operation status.