Bridge module

Details Bridge module Bridge module

1998-07-28

2001-09-18

Dharia, Rupal (Department: 2181)

Electrical computers and digital data processing systems: input/

Intrasystem connection

Bus access regulation

C710S005000, C710S020000, C710S110000, C710S120000, C710S120000, C710S266000, C710S269000, C709S213000, C370S412000, C375S347000

Reexamination Certificate

active

06292862

ABSTRACT:

BACKGROUND OF THE INVENTION
Field of the Invention
The invention relates to a bridge module which is connected between at least two bus systems and is suitable for serial data transfer of binary data from one of the bus systems to at least one other of the bus systems.
Such bus systems may be, for example, local computer networks. In such bus systems or local computer networks, which are increasingly used in motor vehicle electronics, a subscriber station communicates via a data bus with at least one other subscriber station which is connected to the same data bus. See, for instance, German publication DE 35 06 118, which discloses a so-called Controller Area Network (CAN network). The CAN network is an example of such a bus system.
With the increasing requirement for electronic components in motor vehicles, it is advantageous to use more than two local bus systems, for example at different data transmission rates. This also, of course, results in an increased requirement for subscriber stations of different bus systems to be able to communicate with one another. A so-called bridge module may be provided, for example, for the purpose of data transfer between different bus systems.
A bridge module of the above type and which is suitable for data transfer between different bus systems has been described in Jens Eltze, “Double CAN Controller as Bridge for Different CAN Networks,” 4th Int'l Conference, Berlin, 10/1997, pages 15-17 to 15-19. There, particularly in
FIG. 1
, a technical implementation is presented of a programmable bridge module which, for the purpose of data transfer and for data filtering, is arranged between the subscriber stations of two CAN bus systems.
The programmable bridge module described there has a similar characteristic to a central processing unit (CPU) and thus allows data to be processed and handled. A separate micro-processor is required there, to provide an additional CPU for the data transfer and for data filtering. An additional microprocessor, which is used exclusively for the data transfer between different bus systems, is, however, extremely costly.
SUMMARY OF THE INVENTION
It is accordingly an object of the invention to provide a bridge module, which overcomes the above-mentioned disadvantages of the heretofore-known devices and methods of this general type and which allows data to be transferred in a simple manner between at least two bus systems.
With the foregoing and other objects in view there is provided, in accordance with the invention, a bridge module connected in a data transmission system between at least two bus systems for serial data transfer of binary data from one of the bus systems to the other one of the bus systems. The bridge module comprises:
a single memory device for buffer storage of data during a data transfer from one bus system to another bus system, the data transfer in the memory device being carried out under data control without a control device interposed.
In other words, the object of the invention is satisfied by a bridge module that has a single memory device for buffer storage of the data during a data transfer, whereby the data transfer in the memory device is carried out under data control without the interposition of a control device.
The particular advantage of the present invention is thus the provision of a bridge module which is arranged between at least two different bus systems. A single memory device is provided in this case for the data transfer, and is used for buffer storage of the data between the different bus systems. The data transfer, which is controlled by the data to be transmitted, thus takes place completely automatically, that is to say without the interposition of a central processing unit. In this way, it is possible very easily to specify a module which is suitable for data transfer between different bus systems.
In accordance with an added feature of the invention, each of the at least two bus systems has a data bus and a subscriber station connected to the data bus for the purpose of data communication with one another, and wherein the bridge module is integrated in one of the subscriber stations. The memory device which is integrated in the bridge module is specified to have a fixed memory size. It is thus particularly advantageous for the bridge module also to be integrated as part of a subscriber station which is connected to one of the bus systems. In this case, the internal memory of this subscriber station can advantageously also be used as a memory device of the bridge module. In a further advantageous refinement, the memory size of the memory device can be expanded or reduced as desired, depending on the application. In other words, the memory device has a freely configurable memory size.
In accordance with another feature of the invention, the bridge module is connected between no more than the two bus systems.
In accordance with again another feature of the invention, data on a first data bus of a first bus system are driven at a higher data transmission rate than on a second data bus of a second bus system and the bridge module is adapted to transmit the data between the first and second bus systems. In the so-called CAN bus systems with high data transmission rates of up to 1 Mbit/s, the line length of the bus system is limited to 40 m while in CAN bus systems with a relatively low data transmission rate, the line length may be increased up to 1000 m, although in this case a data transmission rate of only about 40 kbit/s is possible. The “fast” bus system and the “slow” bus system can then be coupled to one another using the bridge module.
In accordance with yet another feature of the invention, at least a part of the memory device is configurable as a FIFO buffer memory. Such first-in, first-out memories are suitable in particular for data buffering for a data transfer between the bus systems of different speed.
In accordance with a concomitant feature of the invention, the bridge module according to the invention is arranged between two CAN bus systems in a motor vehicle power supply system.
Other features which are considered as characteristic for the invention are set forth in the appended claims.
Although the invention is illustrated and described herein as embodied in a bridge module, it is nevertheless not intended to be limited to the details shown, since various modifications and structural changes may be made therein without departing from the spirit of the invention and within the scope and range of equivalents of the claims.
The construction and method of operation of the invention, however, together with additional objects and advantages thereof will be best understood from the following description of specific embodiments when read in connection with the accompanying drawings.


REFERENCES:
patent: 5633865 (1997-05-01), Short
patent: 5842038 (1998-11-01), Williams et al.
patent: 6024035 (2000-02-01), Flamme
patent: 35 06 118 C2 (1991-01-01), None
Double-CAN Controller as Bridge for Different CAN Networks, (Jens Eltze), 4th Internaltional Conference, 1997, pp. 15-17 thur 15-19.*
“Double-CAN Controller as Bridge for Different CAN Networks” (Jens Eltze), 4thInternational Conference, 1997, pp. 15-17—15-19.

Affiliated with

Also associated with

Rating

Bridge module does not yet have a rating. At this time, there are no reviews or comments for this patent.

If you have personal experience with Bridge module, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Bridge module will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFUS-PAI-O-2524105