S5-95U, SINEC L2 System Description
1.5 Types of Data Transmission for the S5-95U
There are different types of data transmission that allow for an optimal adaptation to specific needs.
The types of data transmission can be divided into two groups:
• Procedure for communications between active station and active station
- Standard connection
- PLC to PLC connection
- Cyclic I/O (only possible between S5-95Us)
- Layer 2 access
• Procedure for communications between an active station and a passive station
- Cyclical I/O
- Standard connection (broadcasting from active to passive nodes only)
- Layer 2 access
Figure 1-7. Data Transmission Types
S5-95U
S5-95U
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Active
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Passive
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Bus
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Communications
active - active
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Communications
active - passive
The types of data transmission differ from each other by the following:
• The management
• The communications process (implicit/explicit communications*)
• The stations that are to be connected (active/passive stations)
• The kind of data that is to be transmitted or received (e.g. single bytes or data blocks)
Depending on your application, you need to decide on the following issues:
• Should the S5-95U be a passive or an active station on the bus?
• Which type of data transmission do I select?
You will find the answers to these questions below.
*
implicit communication: The communication is automatic; it is not triggered in the user program.
explicit communication: The communication timing is triggered in the user program.
EWA 4NEB 812 6112-02
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