Festo Контроллеры двигателя SFC-LAC - Manual (Page 240)

B. Parametrizing via field bus
B−20
Festo GDCP−SFC−LACI−DN−EN en 0812NH
B.2.3 Rules for job reply processing
Rules Description
1 If the master sends the identifier for No Task", the SFC−LACI replies with the response
identifier for No Reply"
2 A job or reply telegram always refers to a single parameter
3 The master must continue to send a task until it receives the appropriate reply from the
SFC−LACI
4 The master recognises the reply to the job placed:
Ĉ by evaluating the response identifier
Ĉ by evaluating the parameter number (PNU)
Ĉ if applicable, by evaluating the subindex (IND)
Ĉ If applicable, by evaluating the parameter value
5 The SFC−LACI provides the reply until the master sends a new task
6 a) A write task, even with cyclic repetition of the same task, will only be carried out once
by the SFC−LACI.
b) Between two consecutive jobs with the same Job identifier (AK), parameter number
(PNU) and subindex (IND), the Job identifier 0 (no job) must be sent and the Response
identifier 0 (no reply) must be awaited. This ensures that an old" reply is not interĆ
preted as a new" reply.
Tab. B/8: Rules for job reply processing