Siemens DP/AS-Interface Link 20E, Руководство пользователя

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Data Exchange Between the DP Master and AS-i Slave
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DP/AS-Interface Link 20E
Release 11/2002
C79000-G8976-C138–04
2.4 Transferring AS-i Analog Values
Purpose
This section explains how you can access analog values of attached AS-i slaves in
the user program of the DP master.
Notice
The following explanations apply only to AS-i slaves that handle analog value
transfer in compliance with the AS-i slave profile 7.3 or 7.4.
Analog value transfer in compliance with AS-i slave profile 7.1/7.2 is not supported
by the DP/AS-i Link 20E. In this case, analog transfer must be implemented in
your software.
Analog Interface Between the DP Master and
DP/AS-i Link 20E
Analog values are read and written using the acyclic services of PROFIBUS-DP
V1. In the user program of the DP master you use the read_record and
write_record services.
You can operate up to 31 AS-i slaves each with up to 4 analog input or 4 analog
output values. You access the analog values using up to 8 data records (data
record numbers 140–147).