Starting up the device - Configuration
Leuze electronic
BCL 604i
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10
Starting up the device - Configuration
10.1 General information on the PROFIBUS implementation
10.1.1 Communication profile
The communication profile defines how participants serially transmit their data via the transmission
medium. The device supports the communication profile for automation systems and decentral periphery
-> PROFIBUS DP.
DP communication profile
The PROFIBUS DP communication profile is designed for efficient data exchange on the field level. Data
exchange with the decentral devices occurs primarily cyclically. The necessary communication functions
are defined in the DP base functions. The DP optionally offers acyclic communication services as well.
These are used for configuring, operating, observing and alarm handling.
In order to be able to perform data exchange, services are defined which PROFIBUS DP differentiates
between on the basis of the data access points transmitted in the telegram header.
The profile of the device is based on the PROFIBUS profile for identification systems.
10.1.2 Bus-access protocol
The PROFIBUS communication profiles (DP,FMS) use a uniform bus-access process. It is implemented
by layer 2 of the OSI model. The bus-access control (MAC) defines the process for specifying the point in
time at which a network device can transmit data. It must ensure that no more than one participant has
permission to transmit at any given time. The PROFIBUS bus-access process includes the token-passing
process and the master-slave process.
Table 10.1:
PROFIBUS bus-access processes
The two processes can also be mixed in order to create a multi-master system. The device functions both
in a mono-master system as well as in a multi-master system.
10.1.3 Device types
With the PROFIBUS DP, there are two types of master and one type of slave:
Table 10.2:
PROFIBUS DP master and slave types
ATTENTION, LASER RADIATION – LASERCLASS2
Follow the safety notices (see chapter 2.5.1)!
Process
Description
BCL 604i
Token-passing process
With this process, the bus-access permission is distributed by means of a token. The
participant obtains permission to transmit with the token. The token wanders between
the master devices in the ring in a permanently defined time frame. This type of bus
access is used for communication between the masters.
No
Master-slave process
Various slave devices are assigned to a master. The master can address the slaves
which are assigned to it and fetch messages from them. The master always has the
initiative.
Yes
In 2007, the PROFIBUS DP was extended by the DPV2 specification. The specification will then
also permit slave-slave communication. The device does not support this type of communication.
Device type
Description
BCL 604i
Class 1 master (DPM1)
Class 1 masters are defined for the user-data communication.
(e.g.PLC,PC)
Class 2 master (DPM2)
Class 2 masters are defined for commissioning purposes. Additional services facili
-
tate easier configuration as well as device diagnosis.
Slave
The slave is a peripheral device which makes available input data for the control and
receives output data from the control.
X
