Bus repeater for coupling a first and second bus

• US 6,839,789 B2
• Filed: 10/15/2001
• Issued: 01/04/2005
• Est. Priority Date: 10/18/2000
• Status: Expired due to Fees

• Current Assignee: Festo AG & Co.
• Original Assignee: Festo AG & Co.
• Inventors: Krämer, Joachim, Aichele, Alexander
• Primary Examiner(s): Ray, Gopal C.
• Application Number:
  US09/977,466
• Publication Number:
  US 20030074511A1
• Time in Patent Office: 1,177 Days
• Field of Search: 710/305, 710/31, 710/306, 710/313, 710/314, 710/105, 710/200, 370/351, 370/287, 370/492, 370/501, 709/239, 709/253, 375/211, 326/104, 340/825.5
• US Class Current: 710/305
• CPC Class Codes: H04L 5/1461 Suppression of signals in the return path, i.e. bidirectional control circuits

Abstract

A bus-repeater for coupling at least one first bus with a second bus, by way of which data may be transmitted in the form of serial digital signal pulse sequences and including at least one first and a second transmit-receive device, with which the first and, respectively, the second bus may be coupled and by way of which the bus-repeater may transmit signal pulse sequences, received via the first bus on the second bus, and vice versa. In accordance with the invention the bus-repeater includes locking device, which during transmission of a signal pulse received from the first bus to the second bus lock transmission by the bus-repeater of signal pulses, received from the second bus, via the first bus for a transmission locking time and vice versa.

Claims

1. A bus-repeater for coupling at least one first bus to a second bus, by way of which data are transmitted as serial digital signal pulse sequences, comprising at least one first and a second transmit-receive means, to which the first and, respectively, the second bus are coupled and by way of which the bus-repeater transmits signal pulse sequences received from the first bus to the second bus and vice versa, and locking means, which during the transmission of a signal pulse received by the first bus via the second bus lock transmission by the bus-repeater of signal pulses, received from the second bus, via the first bus for a lock time and vice versa.

2. The bus-repeater as set forth in claim 1, wherein the locking means are so designed that same prolong the locking time for a predetermined overrun time.

3. The bus-repeater as set forth in claim 1, comprising unloading means for unloading the first and/or the second bus after performance of transmission of a signal pulse to the first bus or, respectively, the second bus.

4. The bus-repeater as set forth in claim 3, wherein the unloading means include a clocked short circuit switch.

5. The bus-repeater as set forth in claim 3, wherein the unloading means are adapted to be controlled by a voltage level, which is still present after the transmission of a signal pulse by the bus-repeater to the respective first or second bus.

6. The bus-repeater as set forth in claim 3, wherein the unloading means are activated at least during a part of an overrun time and preferably during the entire overrun time.

7. The bus-repeater as set forth in claim 6, comprises a common timer for activating the unloading means and for the formation of an overrun pulse for the locking means.

8. The bus-repeater as set forth in claim 1 adapted to transmit signal pulses received by the first bus without intermediate storage in the second bus and vice versa.

9. The bus-repeater as set forth in claim 1 adapted to re-receive signal pulses, respectively transmitted by it, in the first and the second bus.

10. The bus-repeater as set forth in claim 1, wherein the first and the second buses are CAN buses.

11. The bus-repeater as set forth in claim 10, wherein during the transmission of a dominant signal pulse received from the first bus via the second bus the locking means are activated and vice versa.

12. The bus-repeater as set forth in claim 10, wherein unloading means are activated on transition from a dominant signal level to a recessive signal level.

13. The bus-repeater as set forth in claim 1, wherein the locking means comprise at least one first and one second OR gate for mutual latching, a first input of the first OR gate is connected with a receive output of the first transmit-receive means and a first input of the second OR gate is connected with a receive output of the second transmit-receive means and the output of the second OR gate is at least indirectly connected with a second input of the first OR gate and the output of the first OR gate is at least indirectly connected with a second input of the second OR gate.

14. The bus-repeater as set forth in claim 1, said bus-repeater is designed in the form of an integrated circuit package.

15. A bus connection plug including a bus-repeater as set forth in claim 1.