BECKHOFF BK4000 - Manual (Page 21)

InterBus coupler BK4000 in InterBus S
BK4000 21
InterBus coupler BK4000 in InterBus S
Presentation of the system
The InterBus system is structured as a data ring based on a central mas-
ter/slave access method. It has the structure of a spacially distributed shift
register. With its registers of differing length, each unit is part of this shift
register ring, through which the master shifts the data serially.
Use of the ring structure offers the possibility of synchronous sending and
receiving of data. The two data directions of the ring are accommodated in
one cable.
Each station in the InterBus system has an ID register (identification regis-
ter). This register contains information about the module type, the number
of input and output registers and status and error states.
The InterBus system basically has two operating modes:
- The ID cycle, which is run through to initialise the InterBus system and
whenever requested. In the ID cycle, the interface module reads the ID
registers out of all devices on the bus system and builds up the pro-
cess image on the basis of this information.
- The data cycle, the actual work cycle, which handles data transfer. In
the data cycle, the input data from all devices is transferred out of the
registers into the interface module and output data is transferred from
the interface module to the devices.
System ccnfigurations and
device types The InterBus Club carries a large number of different ID codes. Except for
6 ID codes, these ID codes are used up for couplers of digital and analog
peripherals from Phoenix Contact. Therefore, manufacturer identification
via the ID code is not possible. (Refer to the chapter entitled „ID code and
ID length“ for detailed explanations). Handling of the InterBus BK4000
does not differ from the units from other manufacturers.
The medium: connector and cable
Remote bus connection The InterBus distinguishes between the remote bus, the peripheral bus and
the installation remote bus. The InterBus coupler is equipped with the re-
mote bus interface. The Interbus coupler has an incoming and outgoing
interface on the basis of a D-SUB connector and coupling.
Assignments on the
connector and coupling of
the remote bus cable Outgoing remote bus,
9-pole D-SUB connector Cable Incoming remote bus,
9-pole D-SUB coupling
/DO 6 green 6 /DO
DO 1 yellow 1 DO
/DI 7 pink 7 /DI
DI 2 grey 2 DI
COM 3 brown 3 COM
5 Jumper
9 Jumper