KR20010111936A - Modem apparatus of adsl system - Google Patents

Abstract

The present invention relates to a modem device of an ADSL system in which a memory for implementing an interleaving function is embedded in a UDI and a separate external interface memory can be reduced by jointly using a flash memory of a host controller in a DSP. Core DMT signal processor that supports / decoding, interleaved RAM for interleaving functions, UDI for ADSL framing, FEC, and interleaving functions, AFE for converting digital ADSL signals to analog signals, and management By performing the code overlay function by interfacing with the host controller through a register, the program code for implementing the ADSL function stored in the flash memory in the host controller is downloaded, and the DSP implements the ADSL function, and the operation of each component block is controlled. Code Over to DSP It is characterized by consisting of a host controller that supports the ray function.

Description

Modem device for asymmetric digital subscriber line system {MODEM APPARATUS OF ADSL SYSTEM}

The present invention relates to a modem device of an asymmetric digital subscriber line (hereinafter referred to as 'ADSL') system, and particularly includes a memory for implementing an interleaving function in a universal digital interface (UDI). The present invention relates to a modem device of an ADSL system that can reduce a separate external interface memory by jointly using a flash memory of a host controller in a DSP.

In general, ADSL system utilizes existing telephone line to provide high speed digital services such as data service, Internet service such as interactive service such as Video Of Demand (VOD) service without interfering with not only analog telephone service but also telephone service. It is a system that can provide services.

That is, the ADSL system is a technology that increases bandwidth to simultaneously transmit multimedia information such as voice, graphics, and video while using existing telephone lines, so that multimedia information can be delivered to subscribers without incurring network installation costs. It is attracting attention as a network.

1 is a block diagram of a conventional ADSL system modem apparatus, which includes a core discrete multi-tone (DMT) signal processor 1 that supports encoding / decoding in a transmission / reception path, an ADSL framing, FSL, interface and framer (2) that performs interleaving function, Analog Front End (AFE) (3) that converts digital ADSL signal into analog signal, and program code for ADSL function download A DSP 4 implementing the function, an interleaved RAM 5 storing data for implementing the interleaving function of the interface and the framer 2, and a program code required by the DSP 4; ADSL code memory 6 and a host controller 7 for controlling the operation of each of the building blocks.

The interleaved RAM 5 usually uses a static RAM (SRAM), and the flash memory is used as the ADSL code memory 6.

As described above, the conventional ADSL system modem apparatus has a large and expensive memory such as the interleaved RAM 5 and the ADSL code memory 6 to implement an interleaving function or an ADSL function.

That is, the interleaving function is implemented by directly writing / reading through the interleaved RAM 5 of the interface and the framer 2 at high speed, and the DSP 4 implements the interleaving function. Download the program code from) and implement the ADSL function.

However, since a separate external interface memory is used in the conventional ADSL system modem device as described above, it is difficult to lower the price of the ADSL system modem device any more. There was a problem affected.

SUMMARY OF THE INVENTION The present invention has been made to solve the above problems, and the object thereof is to embed the memory for implementing the interleaving function in the UDI, and to use the flash memory of the host controller in the DSP to reduce the extra external interface memory to reduce the ADSL. It is to provide a modem device of the ADSL system to lower the price of the system modem device.

1 is a block diagram of a conventional ADSL system modem apparatus,

2 is a block diagram of an ADSL system modem apparatus according to the present invention;

3 is a detailed configuration diagram of the DSP of FIG.

<Description of the symbols for the main parts of the drawings>

10 core DMT signal processor 20 UDI

30: AFE 40: DSP

41: host port interface 42: data memory

43: program memory 44: DSP core

50: host controller

The ADSL system modem apparatus of the present invention for achieving the above object, ADSL framing, FEC, interleaving functions while having a core DMT signal processor that supports encoding / decoding in the transmission and reception path, and interleaved RAM for implementing the interleaving function Download the program code to implement the ADSL function stored in the flash memory in the host controller by performing the code overlay function by interfacing with the host controller through the UDI to perform, the AFE which converts the digital ADSL signal into the analog signal, and the management register. And a host controller that controls an operation of each of the building blocks and supports a code overlay function with the DSP.

Hereinafter, with reference to the accompanying drawings will be described in detail the configuration and operation of the ADSL system modem apparatus according to the present invention.

2 is a block diagram of an ADSL system modem apparatus according to the present invention, which includes a core DMT signal processor 10 supporting encoding / decoding in a transmission / reception path and an interleaved RAM for implementing an interleaving function. Code Overlay function by interfacing with host controller through UEC 20 which performs FEC, interleaving function, AFE 30 which converts digital ADSL signal into analog signal, and Management Register. By executing the program code for implementing the ADSL function stored in the flash memory in the host controller to implement the ADSL function, and controls the operation of each of the configuration block, the DSP 40 to implement the code overlay function Supported host controller 50 is configured.

FIG. 3 is a detailed configuration diagram of the DSP 40 of FIG. 2, which illustrates a host port interface 41 performing a management interface with the host controller 50, and data generated through the implementation of an ADSL function in the DSP 40. A data memory 42 for storing, a program memory 43 for storing program code for implementing an ADSL function input through the host port interface unit 41, and a DSP core for implementing an actual ADSL function ( 44).

The operation of the ADSL system modem apparatus according to the present invention configured as described above is as follows.

The core DMT signal processor 10 supports trailing encoding / decoding in a transmission path and a reception path, and performs IFFT / FFT, filtering, and echo canceling functions, respectively.

The UDI 20 has an interleaved RAM for implementing an interleaving function and performs ADSL framing, FEC, and interleaving functions.

In addition, the AFE 30 converting the digital ADSL signal into an analog signal has both digital and analog of the ADSL chipset to perform a function of connecting digital and analog.

Between the core DMT signal processor 10, the UDI 20, the AFE 30, and the DSP 40, addresses and data signals between the ADSL chipsets are passed, and respective control signals, i.e., read, write, A reset or the like is connected and controlled by the DSP 40.

The DSP 40 may simply interface with the host controller 50 through a management register to reduce the amount of software drivers required on the host.

Since the DSP 40 is easily memory mapped to the host controller 50 as an external memory interface, the host controller 50 can easily read / write the management registers in the DSP 40.

That is, the DSP 40 has a structure that can be easily designed by eliminating real-time requirements and reducing driver software by using a management register composed of an interrupt interface or the like.

In addition, the DSP 40 performs a code overlay function to download the program code for implementing the ADSL function stored in the flash memory in the host controller 50 to implement the ADSL function.

That is, program code for implementing the ADSL function input through the host port interface unit 41 is stored in the program memory 43 in the DSP 40, and data generated through the implementation of the ADSL function in the DSP 40 is data. Stored in memory 42, the DSP core 44 implements the actual ADSL functionality.

At this time, the program code required by the DSP 40 is divided into three page codes, that is, core code, training code, and showtime code, and the core code must always exist. The training code is used to determine a link data rate by first checking a line state and then determining an appropriate noise margin and interleaving depth.

The showtime code is a code used only during a steady-state mode connection.

As described above, the DSP 40 code configuration can be sufficiently implemented by the internal memory only if the training code or the showtime code is always present together with the core code.

The function of the DSP 40 according to the interface between the DSP 40 and the host controller 50 is as follows.

As the first code downloading function, the DSP code must be downloaded to the DSP 40. The flash memory attached to the host controller 50 is jointly used without using a separate flash memory as in the related art. .

That is, the host controller 50 searches for a DSP image in the flash memory as a start-up process of the modem device and downloads the code to the DSP 40 through the management interface.

As a second Start Code Execution function, after downloading the DSP code, the host controller 50 interrupts the DSP 40 to execute the software to the DSP 40.

Third Beginning Mode Training (Begin Modem Training) function, when initializing the DSP 40, the connection with ATU-C is initiated without connecting, and the host controller 50 is simple. Only give orders.

As a fourth code overlay function, the host controller 50 should support the code overlay function with the DSP 40.

As described above, the modem apparatus may be applied to and implemented in any system having one broadband access link such as a subscriber modem apparatus of an xDSL system such as VDSL and HDSL in addition to the ADSL system.

In addition, as a modem device for connecting to the ADSL system of the DMT method, if the controller supports the code overlay function, it can be easily implemented in any circuit.

As described above, according to the present invention, the ADSL system modem apparatus reduces the external interface memory by embedding the memory for implementing the interleaving function in the UDI and jointly using the flash memory of the host controller through the management interface in the DSP. It is effective to lower the price of.

Claims (2)

A core DMT signal processor that supports encoding / decoding in the transmit and receive paths, UDI with interleaved RAM to implement interleaving functions and ADSL framing, FEC, and interleaving functions; AFE which converts digital ADSL signal into analog signal, DSP that implements ADSL function by downloading program code to implement ADSL function stored in flash memory in host controller by interfacing with host controller through management register. And a host controller which controls the operation of each of the building blocks and supports a code overlay function to the DSP. The apparatus of claim 1, wherein the DSP is input through a host port interface unit performing a management interface with a host controller, a data memory for storing data generated through the implementation of an ADSL function in the DSP, and the host port interface unit. A modem device for an asymmetric digital subscriber line system comprising a program memory for storing program code for implementing an ADSL function, and a DSP core for implementing an actual ADSL function.