Physical medium dependent sub-system with shared resources for multiport xDSL system

• US 7,200,138 B2
• Filed: 03/01/2001
• Issued: 04/03/2007
• Est. Priority Date: 03/01/2000
• Status: Active Grant

• Current Assignee: Realtek Semiconductor Corp.
• Original Assignee: Realtek Semiconductor Corp.
• Inventors: Liu, Ming-Kang
• Primary Examiner(s): Vu; Huy D.
• Assistant Examiner(s): Ng; Christine
• Application Number:
  US09/798,113
• Publication Number:
  US 20020049581A1
• Time in Patent Office: 2,224 Days
• Field of Search: 370/352, 370/384, 370/387, 370/394, 710/305, 710/310, 710/311, 710/316, 712/34, 712/35, 712/38, 712/225
• US Class Current: 370/352
• CPC Class Codes: G06F 9/3867 using instruction pipelines
• CPC Class Codes: H04L 1/0043 Realisations of complexity reduction techniques, e.g. use of look-up tables
• CPC Class Codes: H04L 1/0052 Realisations of complexity reduction techniques, e.g. pipelining or use of look-up tables
• CPC Class Codes: H04L 12/2856 Access arrangements, e.g. Internet access asynchronous transfer mode networks H04L12/5601; broadband local area networks H04L12/2801; optical access or distribution networks H04Q11/0067; access to open networks H04L12/5691; digital subscriber line end-user equipment and bit-level processing of data on a PSTN-based network H04M11/00; home network gateways H04L12/2834; wireless access networks H04W
• CPC Class Codes: H04L 12/289 Single service
• CPC Class Codes: H04L 2012/5665 Interaction of ATM with other protocols
• CPC Class Codes: H04L 2012/6478 Digital subscriber line, e.g. DSL, ADSL, HDSL, XDSL, VDSL
• CPC Class Codes: H04L 27/2601 Multicarrier modulation systems
• CPC Class Codes: H04L 27/2626 Arrangements specific to the transmitter only
• CPC Class Codes: H04L 27/2647 Arrangements specific to the receiver only equalisation H04L27/01
• CPC Class Codes: H04M 11/062 using different frequency bands for speech and other data
• CPC Class Codes: Y02D 30/50 in wire-line communication networks, e.g. low power modes or reduced link rate

Abstract

A physical medium dependent (PMD) transport subsystem is disclosed which is used in an xDSL communication system. The PMD subsystem coordinates movement of data from an analog front end to a logical pipeline based TC layer, and exchanges common data objects with the latter to increase flexibility of the system. The PMD subsystem includes a number of ASIC blocks for performing signal processing operations, and these ASIC blocks are also shared between ports and are multi-tasking to reduce hardware costs.

Claims

1. A physical medium dependent (PMD) transport subsystem for use in connection with the movement of data objects within a communications system processing a stream of communications data in connection with a remote communications system, the PMD transport subsystem comprising:

transport control means coordinating a first transfer of receive data from the stream of communications data;

wherein said receive data is transferred from a bus interface means coupled to the transport control means for reception by a software-based processing device also coupled to the transport control means;

said transport control means further coordinating a second transfer of an input machine readable data object from said bus interface means to PMD processing circuitry within the PMD transport subsystem;

said input machine readable data object consisting of a structure incorporating a parameter portion and a structured data portion, said input machine readable data object being based in part on said receive data;

wherein the PMD transport subsystem performs a hardware-based computation in connection with a stream of communications data; and

wherein said receive data is received from a communications port by way of a DSL link bus (DSL Link), said DSL Link comprising a plurality of data lines, a word clock line, and a bit clock line, said DSL Link enabling embedded operations control information transfers between one or more analog front ends and the PMD transport subsystem.

2. The PMD transport subsystem of claim 1 further comprising:

a memory means configured for storing said receive data and any output machine readable data objects from the PMD subsystem;

a register means configured to contain data associated with the number of data objects stored in said memory means.

3. The PMD transport subsystem of claim 1 wherein said transport control means provides an output machine readable data object to a transport convergence system associated with a logical pipeline processor, said output machine readable data object being based in part on said input machine readable data object.

4. The PMD transport subsystem of claim 3 wherein said output machine readable data object contains timing data in machine readable form.

5. The PMD transport subsystem of claim 4 wherein said transport subsystem is configured for scheduling the sequenced movement of said output machine readable data object, said sequenced movement being performed in connection with said timing data.

6. The PMD transport subsystem of claim 1 wherein said stream of communications data contains discrete multi-tone (DMT) symbols.

7. The PMD transport subsystem of claim 1 wherein said stream of communications data contains asynchronous transfer mode (ATM) packets.

8. The PMD transport subsystem of claim 1 wherein said parameter portion contains port information associated with the identification of one of a plurality of communications ports.

9. The PMD transport subsystem of claim 1 wherein said PMD and software-based processing device can perform calculations simultaneously.

10. A method of operating a physical medium dependent (PMD) transport subsystem within a communications system that processes a stream of communications data in connection with a remote communications system, the method comprising the steps of:

coordinating a first transfer of receive data from the stream of communications data;

said receive data being transferred for reception by a software-based processing device in the form of an output data object;

wherein said output data object consists of a structure incorporating a parameter portion and a structured data portion, said data object being based in part on said receive data;

coordinating a second transfer of an input data object from said software based processing device for processing by hardware based PMD processing circuitry within the PMD transport subsystem;

performing computations in connection with a stream of communications data using both said hardware-based PMD processing circuitry and said software-based processing device; and

providing a DSL link bus (DSL Link) comprising a plurality of data lines, a word clock line, and a bit clock line for transferring said receive data, said DSL Link enabling embedded operations control information transfers between one or more analog front ends and said PMD processing circuitry.

11. The method of claim 10 further comprising:

providing a memory configured for storing said receive data and said input data object;

providing a register configured to contain data associated with the number of data objects stored in said memory.

12. The method of claim 10 wherein said stream of communications data contains discrete multi-tone (DMT) symbols.

13. The method of claim 10 wherein said stream of communications data contains asynchronous transfer mode (ATM) packets.

14. The method of claim 10 wherein said parameter portion contains stream information associated with a transmit or receive directionality of said stream of communications data.

15. The method of claim 10 wherein said parameter portion contains port information associated with the identification of one of a plurality of communications ports.

16. The method of claim 10 wherein said hardware based PMD processing circuitry and software-based processing device can perform calculations simultaneously for a plurality of communications ports.