Method and apparatus for interfacing between a twisted pair and an intelligent cell

• US 5,548,614 A
• Filed: 04/19/1995
• Issued: 08/20/1996
• Est. Priority Date: 04/20/1993
• Status: Expired due to Term

• Current Assignee: Echelon Corporation (Renesas Electronics Corporation)
• Original Assignee: Echelon Corporation (Renesas Electronics Corporation)
• Inventors: Osterlund, Karl F., Stoll, Kurt A.
• Primary Examiner(s): Chin, Stephen
• Assistant Examiner(s): VO, DON NGUYEN
• Application Number:
  US08/425,715
• Time in Patent Office: 489 Days
• Field of Search: 375/211, 375/220, 375/222, 375/257, 375/377, 370/35, 370/85.3, 370/85.14, 455/7, 455/15, 455/73, 455/88
• US Class Current: 375/211
• CPC Class Codes: H04L 25/02 Details ; arrangements for supplying electrical power along data transmission lines systems for transmitting signals via power distribution lines H04B3/54
• CPC Class Codes: H04L 25/0264 Arrangements for coupling to transmission lines duplexing arrangements H04L5/14; line equalisers, line build-out devices H04L25/03878
• CPC Class Codes: H04L 25/0266 Arrangements for providing Galvanic isolation, e.g. by means of magnetic or capacitive coupling
• 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 25/20 Repeater circuits; Relay circuits
• CPC Class Codes: H04L 5/1461 Suppression of signals in the return path, i.e. bidirectional control circuits

Abstract

A transceiver module for coupling between cells in a distributed intelligence network and a twisted pair line. The module receives power from the line and provides power to its respective cell. At the end of transmitting a packet, the transceiver transmits a code violation, then an anti-code violation to dissipate energy in the line. This is followed by clamping the line for the dead time between packets. N transceivers may be connected (without a cell) to form a repeater. The transceiver module may be used in a network having free topology; that is, an ideal transmission line, with terminators is not needed.

Claims

1. A repeater comprising:

n transceivers for connecting to n lines, each transceiver having a receive data terminal on which data from one of the n lines is coupled, a transmit data terminal for receiving data that is to be transmitted onto the one of the n lines, a transmit enable terminal for receiving a signal that enables transmission onto the one of the n lines, and a carrier detection terminal that provides a signal when a transmission is detected on the one of the n lines;

a first logic means interconnecting the receive data terminals of the n transceivers to the transmit data terminals of the n transceivers; and

,

a second logic means interconnecting the carrier detection terminals of the n transceivers to the transmit enable terminals of the n transceivers.

2. The repeater defined by claim 1 wherein the first and second logic means are OR gates.

3. The repeater defined in claim 1 wherein each of the transceivers disables its data transmission when the signal at its carrier detection terminal is active.

4. A repeater comprising:

a first transceiver for coupling to a first line, said transceiver having a first receive data terminal on which data from the first line is coupled, a first transmit data terminal for receiving data that is to be transmitted onto the first line, a first transmit enable terminal for receiving a signal that enables transmission onto the first line and a first carrier detection terminal that provides a signal when a transmission is detected on the first line;

a second transceiver for coupling to a second line, said second transceiver having a second receive data terminal on which data from the second line is coupled, a second transmit data terminal for receiving data that is to be transmitted onto the second line, a second transmit enable terminal for receiving a signal that enables transmission onto the second line and a second carrier detection terminal that provides a signal when a transmission is detected on the second line;

a first connection between said first receive data terminal of the first transceiver and said second transmit data terminal of said second transceiver;

a second connection between said first transmit data terminal of said first transceiver and said second receive data terminal of said second transceiver;

a third connection between said first transmit enable terminal of said first transceiver and said second carrier detection terminal of said second transceiver, and;

a fourth connection between said first carrier detection terminal of said first transceiver and said second transmit enable terminal of said second transceiver.

5. The repeater defined by claim 4 including an oscillator for providing a clock signal, said oscillator being coupled to said first and said second transceivers.

6. The repeater defined by claim 4 including isolation means for providing isolation within said connections.