X20 system modules • X20 electronics module communication • X20CS1020
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X20 system User's Manual 3.10
4.18.5.6.11 Serial with FlatStream
When using FlatStream communication, the module acts as a bridge between the X2X Link master and an intelligent
field device connected to the module. FlatStream mode can be used for either point-to-point connections as well
as for multidrop systems. Specific algorithms such as timeout and checksum monitoring are usually managed
automatically. During normal operation, the user does not have access to these details.
In a serial network, the module is always the master (DTE). Various adjustments can be made to ensure that
signals are transmitted without errors.
The user can, for example, define a handshake algorithm or set the baud rate in order to adapt the transmission
quality to the requirements of the application.
Operation
When using FlatStream, the general structure of the FlatStream frame must be maintained.
Input/Output sequence
Tx/Rx bytes
(unchanged)
Control byte (unchanged)
Serial frame (without hand-
shake or similar measures)
4.18.5.6.12 Acyclical frame size
Name:
AsynSize
When the stream is used, the data is switched internally between the module and the CPU. For this purpose, a
defined amount of acyclical bytes are reserved for this slot.
Raising the acyclical frame size leads to a raised data throughput on this slot.
Information:
This configuration involves a driver setting which can't be changed during runtime!
Data type
Value
Information
-
8 to 28
Acyclical frame size in bytes. Default = 24
4.18.5.6.13 Minimum cycle time
The minimum cycle time defines how far the bus cycle can be reduced without communication errors occurring.
It should be noted that very fast cycles decrease the idle time available for handling monitoring, diagnostics and
acyclic commands.
Minimum cycle time
200 µs
4.18.5.6.14 Minimum I/O update time
The minimum I/O update time defines how far the bus cycle can be reduced while still allowing an I/O update to
take place in each cycle.
Minimum I/O update time
200 µs
Summary of Contents for X20 System
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