SEW-Eurodrive INTERBUS UFI11A, Руководство пользователя

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Manual – Fieldbus Interface INTERBUS UFI11A
INTERBUS Interface
Establishing the
communications
link with "Initiate" The "Initiate" PCP service establishes a communication link for exchanging parameters
between an INTERBUS master and the UFI11A fieldbus interface. The connection is al-
ways established from the INTERBUS master. Various arrangements relating to the
communication link are checked during establishment of the connection, such as sup-
ported PCP services, user data length, etc. The fieldbus interface responds with a posi-
tive initiate response if the connection is established successfully. If the connection can
not be established, then the arrangements for the communications link on the INTER-
BUS master do not match those on the fieldbus interface. The fieldbus interface re-
sponds with an initiate error response. In this case, compare the configured communi-
cations relationship list in the INTERBUS master with that in the fieldbus interface.
As a rule, an attempt to re-establish an existing communication link leads to an abort.
The communication link is then dropped, which means the "Initiate" PCP service must
be run a third time in order to re-establish the communication connection.
Canceling the
communications
link with "Abort" The "Abort" PCP service cancels an existing communications link between the INTER-
BUS master and the fieldbus interface. Abort is an unconfirmed PCP service and can be
triggered either from the INTERBUS master or from the fieldbus interface.
Reading parame-
ter values with
"Read" The "Read" PCP service gives the INTERBUS master read access to all communication
objects (drive parameters) of the fieldbus interface. All drive parameters and their coding
are presented in detail in the Fieldbus Unit Profile documentation and the list of MOVID-
RIVE
®
parameters.
Writing parameter
values with "Write" The "Write" PCP service gives the INTERBUS master write access to all parameters of
the fieldbus interface. The fieldbus interface generates a write error response if incorrect
access is made to a parameter (e.g. the value written is too large). Precise information
is given relating to the cause of the error.
Parameters in the
object list The "Read" and "Write" PCP services give the INTERBUS master access to all parame-
ters defined in the object list of the UFI11A. All the parameters of the fieldbus interface
which can be accessed via the bus system are described as communication objects in
the static object list of the UFI11A. All objects in the static object list are addressed using
indices. The following table shows the structure of the object list of the UFI11A.