JPH04354459A - Computer integrated modem - Google Patents

Abstract

PURPOSE:To prevent design change from being effected on an NCU section even when a version of an MNP function of, e. g., a MODEM section is revised and the design change is required, to reduce the man-hour for re-design and to increase the degree of freedom in the layout design when the MODEM is integrated in the inside of a communication. CONSTITUTION:A MODEM controlling a communication protocol between computers and modulating/demodulating a signal and an NCU section interfacing a public line are separately formed onto two boards being a MODEM board 1 and an NCU board 2 respectively. The computer integrated MODEM is obtained, in which a modular jack 3 and a connector 4 are provided and the degree of freedom is improved.

Description

[Detailed description of the invention]

0001

[Purpose of the invention]

0002

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a computer built-in modem for data communication with a small computer such as a personal computer.

0003

[Prior Art] All of the modems built into personal computers that have been provided so far are composed of a single board, and a modem section equipped with an MNP (microcomputer network protocol) function is mounted on the board. NCU
(network control unit), in other words, it had a mix of digital and analog circuits.

0004

[Problems to be Solved by the Invention] As mentioned above, in conventional PC built-in modems, the modem part and NCU part are mixed on one board, making it difficult to separate analog and digital circuits. At the same time, if a design change occurs due to, for example, a version upgrade of the MNP function of the modem section, the design of the entire board must be changed, so the pattern of the NCU section, which originally does not need to be changed, must also be adjusted and designed. There was a problem that it was necessary to correct the problem, and it took time and effort to change the design.

The present invention has been made to eliminate such conventional drawbacks. For example, even if the MNP function of the modem section is upgraded and the design is changed, the NC
To provide a computer-embedded modem that does not spread changes to the U section side, reduces man-hours for redesign, and increases the degree of freedom in layout design when incorporated into a computer.

[Configuration of the invention]

[0007]

[Means for Solving the Problems] In order to achieve the above object, the computer built-in modem of the present invention has a modem section that controls communication protocols between computers and modulates and demodulates signals, and an interface between a public line and a public line. The NCU section that performs

[0008]

[Operation] According to the present invention, when the version of the MNP function of the modem section is changed, for example, only the design of the modem board side is changed. Therefore, it is no longer necessary to make design changes to the NCU section as in the past, and the number of man-hours required for design changes can be reduced.

[0009]

Embodiments Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. FIG. 1 is a circuit board diagram of a computer built-in modem according to an embodiment of the present invention.

[0010] This computer built-in modem is an MNP
It is a so-called intelligent modem that is equipped with functions and can control communication protocols, and has a structure that can be incorporated into small computers such as personal computers.

As shown in the figure, this computer built-in modem has an MNP function, controls communication protocols between computers, modulates and demodulates signals, and interfaces with public lines such as telephone dialing. The modem board 1 and the NC part are separated from each other.
It is configured by being mounted on a U board 2. Modem board 1 and N
The CU boards 2 are electrically and mechanically connected to each other via connectors 4, and can be separated as necessary. The modem board 1 is connected to a small computer such as a personal computer via a DTE interface, and the NCU board 2
is connected to a public line 5 via a modular jack 3.

FIG. 2 is a block diagram showing the circuit configuration of the computer built-in modem. Here, the modem section on the modem board 1 side includes a DTE interface 10 that connects to the address bus 31 and data bus 32 on the small computer side, a command interpreter 11 that exchanges commands with the small computer side, and a signal modulation and demodulation system. It is comprised of a modulation/demodulation section 12 that performs the following, and a controller 13 that performs overall control. The command interpreter 11 also includes a command recognition unit 14 that recognizes commands from the small computer side, a command decoding unit 15 that decodes the commands, a memory 16 that temporarily stores commands, and a memory 16 that executes the decoded commands. It is composed of a command execution section 17 and a response code generation section 18 that generates a response code to be sent to the small computer side.

The NCU section on the NCU board 2 side also includes a surge protection circuit 20 that protects the circuit from surges caused by various noises from the public line 5, and a CI detection circuit 21 that detects a calling signal from the public line 5. , an LP detection circuit 22 that detects a DC loop in the public line 5, a DM relay 23 that switches between a modem and a telephone 33 and connects it to the public line 5, and a DP relay 24 that serves as a hook switch and dial pulse sending. , a tone dialer 25 used when dialing in the case of a touch-tone line, and a pulse dialer 2 that sends dial pulses in the case of a dial line.
6, an amplifier 27 consisting of a programmable gain amplifier that adjusts the transmission level and a summing amplifier that matches the DTMF signal and the carrier of the modem, a filter/equalizer 28 that corrects the quality of the transmission and reception carriers, and a modem section. The hybrid circuit 29 mixes/distributes the transmitted and received carriers.

As described above, the modem of this embodiment is constructed by mounting the modem section and the NCU section on two separate modem boards 1 and NCU boards 2, respectively, so that, for example, changes in the version of the MNP function may occur. If the modem board 1
It is only necessary to change the design of the side, there is no need to change the design of the NCU board 2, and the number of man-hours required for the design change can be reduced.

[0015] In the above embodiment, a modem having an MNP function has been described, but it goes without saying that the present invention is not limited to the embodiment and can be applied to all types of modems built into computers.

[0016]

As explained above, according to the computer-embedded modem of the present invention, the modem section and the NCU section are each configured with two separate modem boards and two separate NCU boards, so that the design of one circuit can be changed. Even if the need arises,
Since it is only necessary to change the design of one of the boards, the number of man-hours required for the change can be reduced. Furthermore, by separating the circuit board into two boards, the degree of freedom in layout design is improved when incorporating it into a computer. Analog circuits and digital circuits can be completely separated.

[Brief explanation of drawings]

FIG. 1 is a circuit board diagram of a computer-embedded modem according to an embodiment of the present invention.

FIG. 2 is a block diagram showing the circuit configuration of a computer-embedded modem according to an embodiment of the present invention.

[Explanation of symbols]

1...Modem board 2……NCU board 3……Modular jack ４……Connector 5……Public line

Claims (1)

[Claims] [Claim 1] The modem section that controls communication protocols between computers and modulates and demodulates signals, and the NCU section that interfaces with public telephone lines are separated into two boards, a modem board and an NCU board. A computer built-in modem characterized in that it is configured with a