Bus system and method for exchanging data

• US 20040199701A1
• Filed: 03/08/2004
• Published: 10/07/2004
• Est. Priority Date: 07/17/2001
• Status: Abandoned Application

• Current Assignee: Siemens AG
• Original Assignee: Siemens AG
• Inventors: Eckmuller, Robert
• Application Number:
  US10/484,141
• Publication Number:
  US 20040199701A1
• Time in Patent Office: Days
• US Class Current: 710/305
• CPC Class Codes: H04L 12/40032 Details regarding a bus interface enhancer
• CPC Class Codes: H04L 12/407 with decentralised control
• CPC Class Codes: H04L 2012/40215 Controller Area Network CAN
• CPC Class Codes: H04L 25/0272 Arrangements for coupling to multiple lines, e.g. for differential transmission
• CPC Class Codes: H04L 25/028 Arrangements specific to the transmitter end
• CPC Class Codes: H04L 25/0292 Arrangements specific to the receiver end
• CPC Class Codes: H04L 5/16 Half-duplex systems; Simplex/duplex switching; Transmission of break signals non-automatically inverting the direction of transmission

Abstract

The invention relates to a bus system comprising at least two bus lines (11; 12) whereon a differential level is applied, said level being dominant or recessive. The bus system also comprises at least two transceivers (22) for bidirectional communication in semi-duplex operation which are connected to the bus lines (11; 12) and which transform the differential levels of the bus lines into a digital level, in addition to at least one hardware-interface (231) which is connected to one of the two transceivers (22) for asynchronous, bidirectional communication in full-duplex operation. A CAN bus can be used for storing data or for carrying out a diagnosis without the need for recalling the CAN-protocol.

Claims

1-13. -13. (canceled)

14. A bus system, comprising:

two bus lines for conducting a differential level, wherein said differential level selectively assumes one of a dominant state and a recessive state;

at least two transceivers connected to said two bus lines for bi-directional communication with said two bus lines in half duplex mode, each of said at least two transceivers converting the differential level on said two buses into a digital level; and

a hardware interface connected to one of said at least two transceivers, said hardware interface being capable of asynchronous, bi-directional communication in full duplex mode.

15. The bus system of claim 14, further comprising one of a plug connector and a wireless device connected to said two bus lines, wherein said hardware interface is connected to said one of a plug connector and a wireless device by said one of said at least two transceivers.

16. The bus system of claim 14, further comprising a display device having a plug connector connected to said two bus lines and a controller in a motor vehicle connected said two bus lines, wherein said bus system connects said display device to said controller, and hardware interface is connected to said plug connector by said one of said at least two transceivers.

17. The bus system of claim 14, wherein each of said at least two transceivers comprises a CAN transceiver.

18. The bus system of claim 17, wherein said hardware interface comprises a UART interface.

19. The bus system of claim 14, wherein said hardware interface comprises a UART interface.

20. The bus system of claim 14, further comprising a microcontroller having two hardware interfaces, said two hardware interfaces being connected to the same one of said at least two transceivers.

21. The bus system of claim 20, wherein one of said at least two hardware interfaces comprises a CAN controller.

22. The bus system of claim 21, wherein said CAN controller and the other of said two hardware interfaces are integrated in said microcontroller.

23. A method for interchanging data on a bus system, wherein the bus system includes two bus lines for conducting a differential level, wherein the differential level selectively assumes one of a dominant state and a recessive state, at least two transceivers connected to the two bus lines for bi-directional communication in half duplex mode, each of the at least two transceivers converting the differential level on the two buses into a digital level, and a microcontroller having first and second hardware interfaces, the first and second hardware interfaces being connected to the same one of the at least two transceivers, the first hardware interface being capable of asynchronous, bi-directional communication in full duplex mode, said method comprising the steps of:

activating one of the first and second hardware interfaces and disabling the other of the first and second hardware interfaces when the bus system is first started; and

disabling the one of the first and second hardware interfaces and activating the other of the first and second hardware interfaces if no signals from the one of the first and second hardware interfaces are recognized within a period of time.

24. The method of claim 23, wherein the first hardware interface communicates at different data transmission speed than said second hardware interface.

25. The method of claim 23, further comprising the step of distinguishing between the signals from the first and second hardware interfaces based on at least one of different data transmission speeds, parity errors, data patterns from different communication protocols used by the first and second hardware interfaces.

26. The method of claim 23, wherein the one of the first and second hardware interfaces is a UART interface and the other of the first and second hardware interfaces is a CAN controller.

27. The method of claim 26, further comprising the step of distinguishing between the signals from the first and second hardware interfaces based on different data patterns.