JPS63236443A - Data communication system - Google Patents

Abstract

PURPOSE:To make the exchanging work of a large amount of ROM chips unnecessary, by storing a various kinds of application programs required for line connection in a storage device used in common by each interface vice. CONSTITUTION:In an application storage device 6, plural kinds of line connection procedure programs required for the procedure of the line connection and a various kinds of application programs required for the line connection are stored in advance. A muCPU63, in the case of receiving an application load request from the CPU5 of an exchange system via an interface 62, selects a necessary application from APPs 65-1-65-n, and reads out the program stored in the APPSs and transfers it to data terminal interface devices 2a and 2b connected through a time divisional switch 4 via a communication circuit 64 and an interface 61. In such a way, it is possible to make the exchange of the ROM chip of each data terminal interface equipment unnecessary at the time of changing the procedure of the line connection.

Description

DETAILED DESCRIPTION OF THE INVENTION Technical Field The present invention relates to data communication systems, and more particularly to application operations of data terminal interface devices. 8.

Prior Art Conventionally, data terminal interface devices that function as an interface to data terminal equipment and process line connection procedures have all been implemented using RO as internal firmware.
M (read-only memory). A plurality of line connection procedures are stored in advance in individual ROM chips, and the ROM chips are replaced as necessary.

The conventional data terminal interface device described above has an application program such as a line connection procedure fixedly in the form of a ROM chip.
When attempting to use a procedure different from the line connection procedure in the OM chip, there is the inconvenience of having to replace the already mounted ROM chip with another one. Furthermore, when updating the version of the program, there is also the inconvenience of having to replace all the ROM chips of all the data terminal interface devices connected to the entire system.

As described above, there is a drawback in terms of system operation and maintenance that the work of replacing the ceiling-mounted ROM chip occurs.

OBJECTS OF THE INVENTION An object of the present invention is to provide a data communication system that does not require extensive ROM chip replacement work both in terms of system operation and maintenance.

Structure of the Invention According to the present invention, a plurality of data terminal devices, a time division switch, and a line provided for the data terminal device to form an interface between each of the data terminal devices and the time division switch. A data communication system that has a plurality of data terminal interface devices that perform various controls necessary for connection procedures and line connections, and includes multiple types of line connection procedure programs necessary for line connection procedures and various applications necessary for line connections. A program storage device in which a program is stored in advance is provided in common to the plurality of data terminal interface devices, and necessary line connection procedure programs and application programs are read from the program storage device when initializing the system or changing connection procedures. There is obtained a data communication system characterized in that the data is transferred to each of the data terminal interface devices via the time division switch.

1 凰1 Next, the present invention will be explained with reference to the drawings.

FIG. 1 is a block diagram showing an embodiment of a relay system in a data communication system according to the present invention. Data terminal interface equipment (DCE) 2a is directly connected to a plurality of data terminal equipment (DTE) 1a and 1b, respectively, and interfaces with data terminal equipment 1a and 1b using various line connection procedures.
, 2b are provided. These data terminal interface devices 2a and 2b are connected to an application storage device (APLE) 6 through a time division switch (TDSW) 4 via data line circuits (DLC) 3a and 3b, which are interface devices of the exchange main body, respectively. be done.

The application storage device 6 contains various line connection procedures, such as procedures unique to each company, procedures used by the most popular intelligent modem in North America, and operations such as V and 25bis procedures recommended by CCITT. It stores multiple types of application programs that can be used. The application program may be stored in a ROM, or may be stored in a floppy disk device, hard disk device, etc. as an external storage device.

Note that the central processing unit (CPLJ) 5 is a CPU for controlling the exchange system.

As shown in FIG. 1, each data terminal ink face device 2a, 2b is connected to an application storage device 6 via a time division switch 4, because the application load of each data terminal ink face device 2a, 2b is connected to the application storage device 6 via a time division switch 4. This is when the request occurs. The load request is generated when the operator of the data terminal-like device requests a change in the line connection procedure.

iron, data terminal interface equipment ffff2a, 2
It is necessary to back up the memory with a battery so that the loaded application program does not disappear even when the power of B is turned off. However, even if the backup is not performed, an application load request may be made every time the power is turned on, although it may take some time.

FIG. 2 shows a data terminal interface device 2a.

2b shows a block diagram of an embodiment of 2b. In Figure 2,
The INTF 26 is an interface circuit for interfacing with the exchange system, and processes such as data speed and format exchange are performed in this circuit 26. The microcontroller (μCPtJ) 21 is basically a ROM.
It operates with the program in 22 and communicates with the exchange system side.
The transmission and reception of control signals is controlled by a fixed program in this ROM 22.

The RAM 23 stores a data terminal to be connected or a program that is application software to be run on the device and controls necessary line connection procedures. This program is received in the communication circuit (COMM>25) through the time division switch 4 from the application storage table @6 commonly provided in each data terminal inch face device 2a, 2b within the exchange system. .This program uses battery (B
AT) 24, so that programs loaded from the application storage table N6 do not disappear even when the power is turned off.

Figure 3 shows the data terminal interface @2a.

Each memory area of ROM22 and RAM23 in 2b is shown. The ROM part is IPL (Initial P
This area serves as a program area for programs and control on the exchange system side, and the application area stores loaded programs, and this area serves as a RAM.

FIG. 4 is a block diagram of the application storage device 6. This block diagram shows a case where a ROM chip is used as a method for storing applications. μCPLI63
When it receives an application load request from the CPIJ 5 (Fig. 1) of the exchange system via the interface (INTF) 62, it selects the necessary application from the APs 65-1 to 65-n in the ROM and stores it there. Communication circuit for reading a certain program (COMM)
64. It will operate to transfer the data via the interface 61 to the data terminal interface device connected through the time division switch 4.

In this way, since the various application programs necessary for data line connection of data terminal equipment are stored in advance in the storage table @6 common to each data terminal interface device, the relevant storage device can be stored at the time of system start-up. Necessary application programs can be read out from the computer and transferred and supplied to individual data terminal interface devices. Therefore, when changing the line connection procedure, there is no need to replace the ROM chip of each data terminal interface device. Furthermore, when upgrading a program, it is only necessary to change the application program in the storage device.

As described above, according to the present invention, a line connection procedure program necessary for controlling the operation of a data terminal interface device and various application programs necessary for line connection are stored in advance in a common storage device. Because I am doing this,
When necessary, the necessary programs can be transferred and loaded through the time division switch and operated. Therefore, instead of changing the programs via the data terminal interface 61, the necessary programs can be selected from among the commonly provided programs. This has the effect that all you have to do is read and transfer. Additionally, program version upgrades can be done by simply changing only the commonly provided programs, which can be done with less work.

[Brief explanation of the drawing]

Fig. 1 is a system block diagram of an embodiment of the present invention, Fig. 2 is a block diagram of a data terminal interface device, Fig. 3 is a diagram showing an example of a memory map in the data terminal interface device, and Fig. 4 is an application storage device. FIG. Explanation of main parts No. 2 1a, 1b... Data terminal equipment 2a, 2b...
...Data terminal interface device 4 ...Time division switch

Claims (1)

[Claims] A plurality of data terminal devices, a time division switch, and a line connection procedure and various types necessary for line connection provided for the data terminal device to form an interface between each of the data terminal devices and the time division switch. A data communication system having a plurality of data terminal interface devices for controlling a program storage device that stores in advance multiple types of line connection procedure programs necessary for line connection procedures and various application programs necessary for line connection. The data terminal interface device is provided in common to the plurality of data terminal interface devices, and at the time of system initialization, connection procedure change, etc., the necessary line connection procedure program and application program are read out from the program storage device and transmitted through the time division switch. A data communication system configured to transmit data to each of data terminal interface devices.