5.4 Acyclic Read/Write Request Sequence
A read or write service on a frequency converter parameter takes place as shown in
Illustration 5.2 Acyclic Read/Write Request Sequence
Initiate a read or write on a frequency converter parameter by an acyclic write service on slot 0, index 47. If this write
request is valid, a positive write response without data is returned from the frequency converter immediately. If not, a
negative write response is returned from the frequency converter.
The frequency converter now interprets the PROFIdrive parameter channel part of the data unit and starts to perform this
command internally in the frequency converter.
As the next step, the master sends a read request. If the frequency converter is still busy performing the internal parameter
request, a negative response without data is returned from the frequency converter. This request is repeated by the master,
until the frequency converter has the response data ready for the frequency converter parameter request.
The following example shows the details of the telegrams needed for the read/write service.
Acyclic Communication (DP-V...
Programming Guide
MG06G102
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Summary of Contents for VLT AutomationDrive FC 360
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