JPS63294037A - Data communication equipment - Google Patents

Abstract

PURPOSE:To receive data without paying attention to the communication time and cache at the time of inverting session on the calling side by providing a calling-side data communication equipment with a reception data limit value and a reception data counter. CONSTITUTION:In a calling-side data communication equipment 1-a, the reception limit value is inputted from an external key depressing part 2-4 and is stored in a RAM 2-3 before inversion of session. The reception data counter is counted up at every page by the equipment 1-a when picture and character data are received from a data communication part 2-8, and it is monitored by a CPU 2-1 that the counter value does not exceed the reception limit value. If it exceeds the reception limit value, the call is disconnected by abnormal termination. Thus, data is received without paying sttention to the cache or the like at the time of inverting session on the calling side.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field] The present invention relates to a data communication device having a function of alternating transmission and reception.

[Prior art]

Conventionally, some devices of this type, such as facsimile devices, have a so-called transmission/reception switching function in which the device that made the call gives the transmission right to the other party.

[Problem that the invention is trying to solve] However,
When switching between sending and receiving calls, the communication fee will be charged to the device that originally made the call, even though the other party is transmitting. In this case, there is a problem in that the communication cannot be terminated from the device that originally made the call, and it is not possible to know how much of the total communication it took to receive from the other party, such as fees or time.

[Means for solving problems]

In the present invention, the determining means determines the communication time or the amount of communication data when switching between transmission and reception.

〔Example〕

A practical example of the present invention will be described in detail below with reference to the drawings.

FIG. 1 is a schematic diagram showing an embodiment of a data communication device to which the present invention is applied. In FIG. 1, 1-a is a calling side communication device, 1-b is an exchange, lc is a called side communication device, 1
-d is a line through which data flows.

In Figure 1,! When the device -a makes a call to 1-c, it is sent to 1-c through the exchange 1-b and the line 1-d.
Receive a call. After that, when the call reaches the 5th layer, 1-
a can pass the right to send data to the called party. This is the inversion of the session specified in Recommendation T.62. When 1-c is given the transmission right, it can continue to send data to 1-a. All charges in this case are imposed on the communication device on the 1-a side. Here, according to the present invention, a reception limit value at the time of session reversal is set in advance in the communication device 1-a, and when the amount of data exceeding that amount is received, the call is terminated abnormally and the call is disconnected.

FIG. 2 is a control configuration diagram of the communication device of this embodiment.

2-1 is a CPU that controls the entire communication device, 2-2
is the ROM where the program is stored, 2-3 is the CPU
RAM is a temporary storage device for data used in

2-4 is a key press part from the outside, 2-5 is an image input unit that encodes images, etc., 2-6 is a memory that stores transmitted or received data, and 2-7 is data for printers, displays, etc. An output section, 2-8 is a data communication section that performs communication through a line, and 2-9 indicates data flowing through the line.

The calling communication device in 1-a enters the reception limit value from 2-4 before reversing the session, and the value reaches 2-3.
is stored in Further, the reception limit value does not need to be entered manually (it may be stored in the RAM in advance).When image and character data are received from 2-8, the device 1-a uses a counter according to the present invention. is increased for each page, and 2-1 monitors that the counter value does not become larger than the future limit value.If it exceeds the limit value, it terminates abnormally and disconnects the call from the 1-a device. .

Figure 3 is an example of command response exchange over a line based on the CCITT T.62 recommendation.

In the case of normal communication, the calling party is in charge of billing, and the same can be said for the sequence shown in FIG. 3-1 is a session start command from the transmitting side, which is sent after the call is set up to layer 4. 3-2
is a response command to the start command. At the end of step 3-2, the session becomes open and communication at a higher level than the session becomes possible. 3-3 is a command for the calling party to grant transmission rights to the called party;
4 will be the response. When step 3-4 is completed, the transmission right is transferred to the called side, and the calling side becomes ready to receive data from the called side. The called device that has obtained the right to send data starts transmitting data, and when it completes sending one page, it sends CDPB commands 3-5 to the calling device. 3-6 is a reply to 3-5. Similarly, 3-7 is a command indicating the end of transmission of the second page, and 3-8 is a response to the command for the second page. Here, if the receiving limit value on the calling side is set to 2, the called side device will send the third page of data following the reception of 3-8, but the receiving limit value will not be set on the calling terminal. The call is disconnected when the page counter is compared.

That command is 3-9. 3-10 is a response to 3-9. 3-IO is completed and the fifth layer is disconnected. The communication then enters the procedure for terminating it.

FIG. 4 is a flowchart showing an example of the data communication device in this embodiment. An embodiment will be described below with reference to FIG.

Sl is a step in which the calling terminal device manually sets the reception limit value. This value may be unique to the device.

In S2, the calling side communication device 1-a is the called side communication device l-C.
This is the step in which the call is made to the session layer. 3-2 has been completed. S3
is the step of reversing the session, and 3-3.3
-4 is supported. Through this process, the transmission right is transferred to the called party. S4 is a step in which the calling terminal 1-a receives one page of data from the calling terminal 1-c. S5
is the step of incrementing the counter by one according to the present invention. S6 is a step in which the counter incremented by 1 is compared with the reception limit value set in step 81, and it is monitored whether the counter exceeds the reception limit value. If the limit value is exceeded, C is sent to the called party as shown in 3-9.
Send 3A. That is 87. Thereafter, the process proceeds to step S10 to end the communication. If the counter does not exceed the limit value in S6, the process proceeds to step S8 to determine whether the data has ended. This determination can be easily realized depending on whether the received command is CDPB or CDE. If the data is not completed, the process advances to S4 and starts from data reception. S9 is a step in which the called side hands over the transmission right to the calling side after all data has been received. This is a normal path.

Thereafter, communication ends with SIO.

In the above embodiment, the amount of received data is counted, but counting the reception time is similar to the flowchart in FIG. 4.

Further, if display means for displaying communication time or communication data amount is provided, the operator can easily check the communication time or communication data amount.

Alternatively, communication charges may be displayed.

As explained above, by providing a receive data limit value and a receive data counter on the calling side's data communication device, when the calling side reverses the session, there is no need to worry about communication time and billing (if the calling side is able to receive data) effective.

〔effect〕

As described above, according to the present invention, communication management after transmission/reception switching can be performed.

[Brief explanation of drawings]

Fig. 1 is a schematic diagram of data communication; Fig. 2 is a diagram showing the configuration of the control system within the data communication terminal device; Fig. 3 is a diagram showing the flow of command/response in data communication; Fig. 4 is a flowchart diagram showing the flow of control. 2-1 is a CPU, 2-2 is a ROM, and 2-3 is a RAM. 2-4 is a key press portion, 2-5 is a data input portion, 2-6 is a memory, 2-7 is a data output portion, and 2-8 is a data communication portion.

Claims (2)

[Claims] (1) A data communication device characterized by having a transmitting means for transmitting data, a receiving means for receiving data, and a means for determining communication time or amount of communication data after switching between transmitting and receiving. . (2) The data communication device according to claim 1, wherein the data communication is terminated when the determining means determines that a predetermined time has elapsed or that a predetermined communication data amount has been reached.