JPS63199563A - Communication terminal equipment - Google Patents

Abstract

PURPOSE:To automatically connect a line, and to lighten the trouble of an operation by providing an opposite party designating means to designate the opposite party of a communication, a terminal designating means to designate the terminal of the opposite party, and a means to designate only the opposite party when an answer from the terminal designated by the terminal designating means in not returned. CONSTITUTION:An operator inputs the opposite party dial number attached with a subaddress. When the calling side terminal receives a CONN command, it decides which the command is an affirmation command or a negation command. When it judges that it has received the affirmation command, it transmits a connection complete CONN ACK command, shown by 45 in a figure, to the calling side terminal, and a communication state is established. When it receives the negation command, the calling side terminal automatically deletes the subaddress from the opposite party dial number, and transmits the opposite party dial number without the subaddress. Accordingly, even when the subaddress of a callee terminal has been changed, the line is connected to the opposite party side terminal without any judgement of the calling side operator, and a communication can be performed.

Description

Detailed Description of the Invention [Technical Field] The present invention relates to a communication terminal device used in a communication system to which more communication terminals than the number of communication lines are connected.

[Prior Art] Conventionally, as this type of communication system, for example, 15DN
(Integrated Ser-vices
Digital Network) system is known. This l5DN line has two data channels (B channel) and one control channel (
It has three communication channels: D channel). In the I5DN system, up to eight terminals are connected to this one line. In 15DN, there is a common address common to all destination terminals and subaddresses given to individual terminals. When calling the other party, if you specify only the common address, all terminals of the other party will be called and one of them will be connected, and if you specify a subaddress in addition to the common address, the specified subaddress will be called. The terminal's □ only is called.

[Problem to be solved by the invention] The above-mentioned l5D
In the N system, if you specify a terminal using a subaddress, only the specified terminal will be called, so if the terminal corresponding to that subaddress is busy (in use) or there is no corresponding terminal, the operator who connects the line will The drawback is that only the common address must be designated once again and the call must be made again.

[Means and effects for solving the problem] In the present invention, a destination specifying means for specifying a communication destination, an end unspecified means for specifying a communication partner terminal, and a terminal specified by the end unspecified means. By providing a means for only specifying the destination when there is no response from the terminal, the line can be automatically connected and the effort required for operation can be reduced.

[Embodiment] An embodiment of the present invention will be described in detail below with reference to the drawings. In the following embodiments, an ISDN system will be explained as an example.

1 to 5 are diagrams for explaining the present invention in detail, and FIG. 1 is a connection diagram in which the communication terminal device of this embodiment is connected to the 15DN network. Reference numeral 1 denotes a digital telephone according to this embodiment, 2 a bus line connecting the network termination device 3 and a plurality of terminals, 3 a network termination device serving as a network termination, 4 an ISDN exchange, and 5
6 is a digital facsimile machine connected to the other party's network terminating device, and 6 is a digital telephone connected to the other party's network terminating device. FIG. 2 is an external view of the digital telephone of this embodiment. 21 is a digital telephone body, 22 is a handset, and 23 is a key button for manually inputting a telephone number, etc. FIG. 3 is a block diagram showing this embodiment. In FIG. 3, 31 is a digital telephone body, 3.2 is a central processing unit, 33 is an EPROM, 34 is a RAM, 35 is an I10 controller, 36 is a codec, 37 is a communication chip, 38 is a key button, 39 is a handset, 40 is an l5DN line.

FIG. 4 is a diagram showing a signal sequence of a digital telephone in ISDN MIJ.

In the called terminal B of FIG. 4, 41 is a call request command (SET UP), and 42 is a call denial command (CON
N NEG), 43 is calling = 3 man I: (A
LERT), 44 is a response command (CONN), 45 is a connection completion command (C0NNACK), 46 is call data (B-CH signal), 47 is a disconnection instruction command (DIS)
C), 48 is a recovery request command (REL), and 49 is a recovery confirmation command (REL COM).

Next, the operation of the above embodiment will be explained.

FIG. 5 is a flowchart showing the operation of the above embodiment.

When making a call at 51 in FIG. 5, the operator inputs the dialed number of the other party with a subaddress into the terminal at S2.

Next, the terminal which received the dialed number of the other party in step 53 starts a call operation and sends the setup command shown in FIG.
Send to DN network.

In S4, the calling terminal is C0N of 44 and 42 in Fig. 4.
Wait for N command to be received. When a C0NN command is received, it is determined in S5 whether the command is an affirmative command or a negative command.

In S5, when it is determined that an affirmative command has been received, the calling terminal transmits the C0NN ACK command shown in FIG. 4, and enters the talking state in S6 (FIG. 4, 46). Next, the call ends at 57, and the calling terminal receives the DI as shown in Figure 4, 47.
When an SC command is received, a REL command is sent,
By receiving the REL C0M command, the disconnection of the rope can be confirmed and the communication ends.

Next, in step 35, if a negative command is received,
Since the terminal corresponding to the transmitted sub-address may not exist, in S8 the calling terminal automatically deletes the sub-address from the dialed number of the other party input in 52,
Send the other party's dialed number without subaddress. Next, the calling terminal waits to receive the C0NN command in S9. When a C0NN command is received, the SIO determines whether the command is an affirmative command or a negative command. If it is an affirmative command, a call is made in S6, and the network is disconnected in S7.

In SIO, if it is determined to be a negative command, S7
to disconnect the network and end communication.

In the above embodiment, a call is made using the destination dial number with a subaddress, and if there is no corresponding terminal on the other party's side, the subaddress is deleted and the call is made again. However, depending on the type of 15DN network, subaddress = 0 means that no subaddress is specified. There are some networks that interpret the call as 0, so in that case, it may be possible to re-call using the dialed number of the other party with subaddress = 0. Furthermore, in the above embodiment, when a negative C0NN command is received, a re-call is made in all cases. It is also possible to make a re-call only when the reason code allows connection.

As explained above, if the calling terminal cannot connect even if the calling terminal makes a call using a dialed number with a subaddress, the calling terminal automatically converts the number to the dialed number without specifying a subaddress and re-calls. By adding , even if the subaddress of the called terminal has been changed, it is now possible to connect to and communicate with the other party's terminal without any judgment from the calling operator.

[Effects] As described above, according to the present invention, lines can be automatically connected and operability can be improved.

[Brief explanation of the drawing]

FIG. 1 is a connection diagram in which the communication terminal device of this embodiment is connected to the 15DN network, and FIG. 2 is an external view of the digital telephone of this embodiment. FIG. 3 is a block diagram showing the configuration of this embodiment,
FIG. 4 is a diagram showing a signal sequence of a digital telephone in 15DNtA, and FIG. 5 is a flowchart for explaining the operation of this embodiment. 1 is a digital telephone, 2 is a bus line, 3 is a network termination device, 4 is an 15DN exchange, 5 is a digital facsimile device, and 6 is a digital telephone.

Claims (1)

[Scope of Claims] In a communication terminal device used in a communication system to which communication terminal devices are connected in a number equal to or greater than the number of communication lines, a destination specifying means for specifying a communication destination, and a communication specified by the destination specifying means. Terminal specifying means for specifying a desired communication terminal device of the other party; and means for only specifying the communication destination using the destination specifying means when there is no response from the communication terminal device specified by the terminal specifying means. A communication terminal device comprising: