JPH03192938A - Data terminal equipment - Google Patents

Abstract

PURPOSE:To attain communication between data terminal equipments through direct coupling of a cable by providing a means selecting either an equipment connection system at the time through a telephone circuit network or an equipment connection system at the time through a cable direct connection prior to the communication. CONSTITUTION:Let left end data terminal equipment 1a be a caller and let a right end data terminal equipment 1b be a called party, then the caller data terminal equipment 1a connects either a protocol section 5 at via a telephone circuit network or a protocol section 6 at via cable direct connection to an application section 2 of a communication control section 3 via a protocol selection section 4 depending whether the equipment connection system is a telephone circuit network 13 or cable C3 direct connection prior to the communication with personal computer communication equipment communication system (JUST PC) communication equipments 8a, 8b in compliance with the Notification No.971 of the Ministry of Posts and Telecommunications being opposite communication equipments or a called party data terminal equipment 1b. Thus, inter data terminal equipment communication in a same floor of cable direct connection is implemented.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a data terminal device such as a personal computer.

[Conventional technology]

Conventionally, the recommended communication method for personal computer communication equipment (hereinafter referred to as JUST PC) of the Ministry of Posts and Telecommunications Notification No. 971 has been widely used as a communication method between data terminal devices such as personal computers using a telephone line network.

[Problem to be solved by the invention]

The above-described JUST PC requires a JIIST PC communication device and a telephone line network for communication between data terminal devices, and therefore has the disadvantage that the data terminal devices cannot be directly connected by cable.

An object of the present invention is to provide a data terminal device that solves the above problems.

[Means to solve the problem]

In order to achieve the above object, the data terminal device according to the present invention is a data terminal device having a function of communicating via a communication device and a telephone line network, and a communication function by direct cable connection. , when communicating with a data terminal device on the called side via the communication device and the telephone line network, a means for realizing communication by a control functional element on the data terminal device side, and a means for realizing communication with a control function element on the data terminal device side, and a means for realizing the communication with a data terminal device on the called side through a direct cable connection; The communication device has means for realizing communication by a control functional element on the side of the communication device when communicating with a terminal device, and means for selecting one of the two means before communication.

〔Example〕

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

FIG. 1 is a device connection system diagram when the data terminal device according to the present invention is connected via a telephone line network, and FIG. 2 is a device connection system diagram when the data terminal device according to the present invention is directly connected by cable.

In FIG. 1, la and lb are data terminal devices, 8a,
8b is the recommended communication method for personal computer communication equipment according to Ministry of Posts and Telecommunications Notification No. 971 (hereinafter referred to as JUSTPC)
The data terminal devices 1a, 1b and JUST PC communication devices 8a, 8b are connected via straight cables CI, C2, and both JUST PC communication devices 8a , 8b are connected via a telephone line network 13. Further, in FIG. 2, the data terminal devices la and 1brrf1 are directly connected via a cross cable C3.

FIG. 3 is a functional block diagram of a data terminal device on the calling side in the present invention.

In FIGS. 1 and 2, the leftmost data terminal device 1a is assumed to be the calling side, and the rightmost data terminal device 1b is assumed to be the called side. The data terminal device 1a on the calling side is a JIIST PC communication device 8a which is a communication partner device.

8b or the called data terminal device 1b, whether the device connection system is the telephone line network shown in FIG.
Or, depending on whether it is a direct cable connection as shown in Figure 2,
Either the protocol section 5 when connected via a telephone line network or the protocol section 6 when connected directly to a cable is connected to the abrigation section 2 of the communication control section 3 via the protocol selection section 4.

The protocol section 5 when going through the telephone line network is the JUS in Fig. 4.
By implementing the functional control elements on the data terminal device side specified by the TPC, the connection connection communication sequence shown in Fig. 6,
The data transfer communication sequence shown in FIG. 8 and the connection disconnection communication sequence shown in FIG. 10 are performed to realize communication via the telephone line network.

When the cable is directly connected, the protocol section 6 is Jt in Fig. 5.
It realizes the functional control elements on the JUST PC communication device side that are not specified by lST PC, and performs the connection connection communication sequence in Figure 7, the data transfer communication sequence in Figure 9, and the first
Perform the connection disconnection communication sequence shown in Figure 1 to realize communication during direct cable connection.

The protocol section 5 or 6 communicates with J via the communication drive section 7.
UST PC communication device 8a, 8b or data terminal device 1
Transmits and receives electrical signals to and from b.

The data terminal device 1b on the called side implements only the function control elements on the data terminal device side defined by JUST PC in FIG. 4 when via the telephone line network or when connected directly by cable.

〔Effect of the invention〕

As explained above, the data terminal device on the calling side of the present invention uses the control functional elements on the data terminal device side specified by JIIST PC to communicate with the data terminal on the called side via the JUST PC communication device and the telephone line network. It is possible to perform communication with the device specified by JUSTPC, and also
The control function elements on the JUST PC communication device side specified in C. make it possible to communicate with the data terminal device on the called side on the same floor that is directly connected to the JUST PC communication device by cable, without going through the telephone line network. There is an effect that can be achieved.

[Brief explanation of drawings]

FIG. 1 is a device connection system diagram when the data terminal device according to the present invention is connected via a telephone line network, FIG. 2 is a device connection system diagram when the data terminal device according to the present invention is directly connected by cable, and FIG. FIG. 4 is a functional block diagram of the data terminal device on the calling side in the invention; FIG. 4 is a diagram showing functional control elements when via a telephone line network; FIG. 5 is a diagram showing functional control elements when connected directly to a cable; FIG. is a connection connection communication sequence diagram when going through a telephone line network, Figure 7 is a connection connection communication sequence diagram when a cable is directly connected, Figure 8 is a data transfer communication sequence diagram when going through a telephone line 1I4, and Figure 9 is a cable direct connection diagram. Data transfer communication sequence diagram during connection,
FIG. 10 is a connection disconnection communication sequence diagram when going through a telephone line network, and FIG. 11 is a connection disconnection communication sequence diagram when a cable is directly connected. la, lb...Data terminal device 2...Application section 3...Communication control section 4...Protocol selection section 5...Protocol section 6 when via telephone line network...When connected directly to cable Protocol section 7...communication drive section

Claims (1)

[Claims] (1) A data terminal device having a function of communicating via a communication device and a telephone line network, and a communication function with a direct cable connection, which is a data terminal device having a function of communicating via a communication device and a telephone line network, and a receiving side via the communication device and a telephone line network. A means for realizing communication with a control function element on the data terminal device side when communicating with a data terminal device on the called side; A data terminal device comprising: means for realizing communication using functional elements; and means for selecting one of the two means prior to communication.