Softing FG-200 HSE/FF, Руководство пользователя

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FG-200 HSE/FF Modbus - User Manual
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Version EN-112021-1.30.3
9
Appendix
9.1 FOUNDATION Fieldbus basics
9.1.1 Link active scheduler
The link active scheduler (LAS) is a deterministic, centralized bus scheduler that controls the
communication in the H1 segment. It is responsible to maintain the live list.
9.1.2 Visitor host
A visitor host is a secondary on-process host typically used for asset management and device
maintenance. The visitor host uses CLT/SRV connections only. It usually should be assigned to node
addresses in the range from 252 to 255.
9.1.3 Live list
The Live list is a list of all currently active devices.
9.1.4 Publisher/subscriber links (PUB/SUB links)
Publisher/subscriber links is used for cyclic transfer of process values (input data and output data). The
process value is send by a publisher. Multiple subscribers linked to the publisher are able to receive the
process value.
The LAS coordinates the cyclic data transfer on base of a synchronized system time. The cyclic data
transfer is synchronized with the execution of the function blocks in the field devices. The schedules for
cyclic data transfer as well as for the execution of the function blocks are generated by the comConf tool.
Input data
In case of input data the input function block executed and immediately after the function block execution
the new data are transmitted over the line.
Output data
In case of output data the output function block is executed immediately after the transmission of the
output data.