JPH0486937A - Data communication control system - Google Patents

Abstract

PURPOSE:To process all the inputted data by prohibiting the input of the data from a second host device when receiving the data form a first host device by terminal equipment, and releasing prohibition at a time when the processing is completed. CONSTITUTION:When the data AD1 from a host device A is received by an emulator 3, an affirmative response signal AR1 is transmitted to the device A, and simultaneously, interruption prohibition is applied for the processing period TA of the data AD1. The data BD1 transmitted from the host device B is stopped in a state where it is fetched in a buffer 5. When the processing of a terminal application 1 is completed, the interruption prohibition is released, and the data BD1 is fetched in a buffer 2b. Simultaneously with the transmission of an affirmative response signal BR1 to the device B, the interruption prohibition for the processing period TB of the data BD1 is applied. The data BD2 from the device B remains being kept with the buffer 5. When the processing of the data BD1 is completed, the interruption prohibition is released, and the data BD2 is fetched in the buffer 2b.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a data communication control method for controlling data communication between a plurality of host devices and a common terminal device.

[Conventional technology]

Conventionally, in this type of data communication control system, applications on the host device and the terminal device are synchronized when a certain data transfer from the host device to the terminal device is completed. Then, a response request signal is output to the host device, and an acknowledgment signal is output from the host device.

That is, when a certain transfer unit of data, for example, one screen worth of data, is output from the host device, a response request signal is output to the terminal device when the data transfer is completed. When the terminal device receives this response request signal, if the data has been correctly received, an acknowledgment signal is sent to the host device. At this time, the host device stops transmitting the next data until it receives the acknowledgment signal.

Here, a case will be described in which communication between the host device side and the terminal device side is performed in the above-described acknowledgment method, for example, in the sequence shown in FIG. 3. In the sequence shown in FIG. 2, first, data AD is sent from the first host device A.
I is not sent to the terminal device, and the above-mentioned acknowledgment signal ARI is sent from the terminal device. Next, the second host device B
The data BDI is sent to the terminal device while the terminal device sends an acknowledgment signal BRI. Next, data BD2 is also sent from the second host device B, and an acknowledgment signal BR2 is sent to this second host device B.

FIG. 4 is a time chart showing control operations when data communication is performed in the above sequence. The data ADI output from the above-mentioned host A is sent to the communication control device (CC).
U) and input to the emulator. Then, an acknowledgment signal ARI is transmitted from the emulator to the host A, and the data ADI is processed by the application (terminal APP) of the terminal device. Similarly, data BDI, BD2 from host device B
Also, acknowledgment signals BRI and BR2 are transmitted, and the data BDI and BD2 are processed.

TA and TB indicate processing periods for each of the above data.

[Invention or problem to be solved]

Since the conventional data communication control system is configured as described above, for example, as shown in FIG. When trying to start processing
If the next data BD2 from host device B has already been received, the previous data B from host device B
There was a problem in that the DI was not processed and the next data BD2 was processed, leaving the data BDI unprocessed.

The present invention was made to solve these problems, and an object of the present invention is to provide a data communication control system that can process all data from each host device.

[Means to solve the problem]

A data communication control method according to the present invention is a data communication control method that controls data communication between a plurality of host devices and a common terminal device, and when data is transmitted from a first host device to a terminal device, outputting a response request signal to the first host device, prohibiting manual input of data transmitted from the second host device to the terminal device, outputting a response signal from the first host device to the terminal device, and When the terminal device finishes processing the data transmitted from the first host device, the prohibition is canceled and the data from the second host device is input to the terminal device.

[Effect]

In the data communication control method of the present invention, when the terminal device receives data from the first host device, manual input of data from the second host device is prohibited, and when the processing of the data is completed, the above prohibition is prohibited. Since it is controlled to release the data and input data from the second host device, all manually entered data is processed.

(Embodiment) FIG. 1 is a block diagram of a data communication control system according to an embodiment of the present invention. In the figure, 1 is a terminal application of a terminal device, and data AD is sent to the first host device and from the second host device B.

BD processing is performed here. 2a and 2b are buffers that temporarily hold those data AD and BD, and 3 is data AD in these buffers 2a and 2b.

4 is the communication control device (CCt+) that controls the whole, 5 is the CCU buffer, and line 6 is the emulator that imports the BD.
The data AD and BD of the host devices A and B transmitted through the CCU buffer 5 are taken into the CCU buffer 5. 7
is an interrupt control section that controls the input/output of each data and each signal mentioned above.

In the data communication control system configured as described above, control is performed that combines the conventional acknowledgment control described above and interrupt control for inhibiting and canceling interrupts from the communication control device 4. That is, data AD is transmitted from the first host device A to the terminal device, and when the transmission is completed, an acknowledgment request signal AS is output to the first host device A, and at the same time, the data AD is transmitted from the second host device B. Data B
D's human power is the interrupt disable signal DI from emulator 3.
prohibited by. Then, when the first host device A outputs the acknowledgment signal AR to the terminal device and the terminal application 1 of the terminal device finishes processing the data AD, the interrupt prohibition release signal El from the terminal application 1 causes the above-mentioned The prohibition is lifted, and data BD from the second host device MB is input to the terminal device. Similarly, data BD, acknowledgment request signal BS, and acknowledgment signal BR are transmitted between the second host device B and the terminal device.
is sent and received.

Next, the control operation when data communication is performed in the sequence shown in FIG. 3 mentioned above will be explained with reference to the time chart of FIG. 2.

First, data for one screen, that is, data ADI for a processing unit of terminal application 1, is transmitted from the host device A, and when the terminal device receives this data ADI,
An acknowledgment signal ARI is sent to the host device A. Also, for host device B, data BDI, BD
2 and each signal is transmitted and received.

Here, conventionally, as shown in FIG. 4, when data BDI is transmitted from host device B during processing period TA of data ADI of host device A, emulator 3 sends data to buffer 2.
The data BDI is taken into b, and the acknowledgment signal BRI is sent to
is sent to host B. Furthermore, when the next data BD2 is transmitted from the host B during the processing period TA, the emulator 3 takes that data BD2 into the buffer 2b, and
Send an acknowledgment signal BR2 to host B. For this reason,
The processing of data ADI from host device A is completed in terminal application 1, and the first data BDI of host B is
When attempting to start processing, the buffer 2b for host B has already been overwritten with the next data BD2, so data BDI is not processed, but data BD2 is processed.

However, in this embodiment, as shown in FIG. 2, when the reception of the data ADI from the host device A is completed, the acknowledgment signal ARI is transmitted, and at the same time, interrupts for the next data input are disabled. Then, when the above data ADI processing is completed, the above prohibition is lifted and the next host B
Data BDI from is input.

That is, when data ADI from the host device HA is received by the emulator 3 via the communication control device 4, an acknowledgment signal ARI is sent to the host device A, and at the same time, the processing period TA of the data ADI is Interrupts can be disabled for a while.

Therefore, the data BDI transmitted from the host device B during the same processing period TA remains in the buffer 5 of the communication control device 4 as shown in FIG. Thereafter, when the processing of the terminal application 1 is completed, the above-mentioned interrupt prohibition is canceled, and the data BDI of the host device B, which has been fetched into the buffer 5, is fetched into the buffer 2b.

Then, at the same time that the acknowledgment signal BRI is transmitted to the host device B, interrupts are disabled during the processing period TB of the data BDI. Therefore, the data BD2 sent from the host device B during this period TB remains held in the ccU buffer 5 as described above. Thereafter, when the processing of the data BDI by the terminal application 1 is completed, the interrupt prohibition is canceled and the data BD2 sent during the processing period TB is taken into the buffer 2b of the emulator 3. Then, an acknowledgment signal BR2 is transmitted to the host device B, and interrupts are disabled in the same manner as above, and the terminal application 1 processes the data BD2 during this period.

In this way, each data ADI, BDI, and BD2 of host device A and host device B will not end up unprocessed.
Everything will be processed correctly and reliably. At that time, in the communication between two host devices A and B that support the same communication procedure and the terminal device, each host device A and B can communicate with the terminal device independently, and each host application It is possible to send data to. All data of each host application and terminal application is guaranteed.

〔Effect of the invention〕

As described above, according to the present invention, it is possible to reliably process all data from each host device.

[Brief explanation of drawings]

FIG. 1 is a block diagram showing an embodiment of the present invention, FIG. 2 is a time chart showing the control operation of the device in FIG. 1, and FIG. 3 is a sequence of communication data between a host device and a terminal device. The explanatory diagram, FIG. 4, is a time chart showing a conventional control operation. 1------One terminal application 2a, 2b==・Buffer 3------Emulator 4---Communication control device 5...CCU buffer 6---Line The same reference numerals in the middle indicate the same or corresponding parts.

Claims (1)

[Claims] In a data communication control method that controls data communication between a plurality of host devices and a common terminal device, when data is transmitted from a first host device to a common terminal device, the first
outputs a response request signal to the first host device, prohibits input of data transmitted from the second host device to the terminal device, outputs a response signal from the first host device to the terminal device, and outputs a response request signal to the terminal device. A data communication control method characterized in that when processing of data transmitted from the first host device is completed, the prohibition is canceled and data from the second host device is input to the terminal device.