Siemens SINAMICS G120 Operating Instructions Manual page 229

Rules for processing requests/responses
● A request or a response can only ever refer to one parameter.
● The master must repeat a request continuously until it has received the appropriate
● The master detects the response to a request it has sent by
● The complete request must be sent in one telegram. Request telegrams cannot be split.
● In the case of response telegrams which contain parameter values, the drive always
● If no information needs to be fetched from the PKW interface in cyclical operation (only
Control Units CU240S
Operating Instructions, 11/2006, A5E00766042B AA
response.
– evaluating the response identifier,
– evaluating the parameter number PNU,
– evaluating the parameter index IND if necessary, or
– evaluating the parameter value PWE if necessary.
The same applies to responses.
returns the momentary parameter value when repeating response telegrams.
PZD data are relevant), then the "No request" request telegram must be issued.
Functions
8.7 Communication via USS
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