VIPA CPU 21 Series, Руководство пользователя

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Chapter 10 Deployment CPU 21xSER-2 Manual VIPA CPU 21x
10-16 HB103E - Rev. 05/45
The FETCH block initializes a FETCH order in the partner station.
The FETCH order defines data source and destination and the data source
is transmitted to the partner station.
The CPU from VIPA realizes the definition of source and destination via a
pointer parameter.
The partner station provides the Source data and transmits them via
SEND_ALL back to the requesting station. Via RECEIVE_ALL the data is
received and is stored in
Destination .
The update of the indicator word takes place via FETCH res. CONTROL.
Please regard that a fetch command is only executed when the following
conditions are met:
•
the FETCH has received a VKE "1"
•
the Bit "order in process" in the indicator word has been reset
The purpose of the CONTROL block is the following:
•
Update of the indicator word
•
Query if a certain order of the CP is currently active, e.g. request for a
receipt telegram
•
Query the CP which order is recently in commission.
The block is independent from the VKE and should be called from the
cyclic part of the application.
SFC 232 - FETCH
Parameter
SFC 233 - CONTROL
Parameter