JPH05183602A - Basic data transmission/control system - Google Patents

Abstract

PURPOSE:To attain the quick transmission of an information message by discriminating that its own station is a priority station so as to set a priority flag given to a message. CONSTITUTION:A text generated by a data processing section 27 of an electronic computer main body is sent to a line equipment 21 via a message management section 26 controlled by an input output control section 24, a message transmission section 25 and a communication control section 22. The reception is similarly implemented through the sections above. When a block number (BSC) added to the message is the same, the control section 24 discriminates it as collision and also whether or not its own station has the highest priority. When the priority is highest, a priority flag is set, the text is processed with priority even at collision and the information message is sent quickly and the information transmission to an opposite station and information exchange with the opposite station are surely implemented.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a basic data transmission control system, and more particularly, in data transmission between a data terminal device or a data processing device using a data transmission line, the mutual devices promote each other. Not spontaneously,
The present invention also relates to a basic data transmission control method that improves the reliability of transmission control when information is quickly and accurately transmitted to a partner device.

[0002]

2. Description of the Related Art In the conventional data transmission control system,
After establishing the relationship between the master station and the slave station by the forward monitoring sequence that sends out the ENQ transmission control character, the master station sends an information message, and confirmation of the transmission is performed by the response of the backward monitoring sequence. That is, the station that can first send the information message could send the information message for the first time after being specified by the mutually determined procedure.

[0003]

In the above-described conventional type of data transmission control procedure, the master station, especially the slave station, cannot send an information message instantly each time a send request is made, and the relationship between the master station and the slave station is lost. There is always a time delay to establish.

[0004]

The basic type data transmission control system of the present invention is a data transmission control procedure of a point-to-point system which is performed between data terminal devices or data processing devices connected by a transmission line. It is assumed that the message or the monitoring sequence has a priority flag area, and the ON or OFF state is set in the priority flag area, and the block number (circulation number or order) attached to the message or the monitoring sequence. (Number system such as number), a step of determining the same collision, a step of determining whether or not the own station is a priority station, and a step of setting the priority flag to ON or OFF in a message to be transmitted or a message to be retransmitted. .

[0005]

Embodiments of the present invention will now be described with reference to the drawings.

FIG. 1 is a flow chart showing an example of the operation in one embodiment of the basic data transmission control system of the present invention,
FIG. 2 is a block diagram of an apparatus according to this embodiment, and FIG. 3 is a diagram showing a configuration of a message and a monitoring sequence used in the basic data transmission control method according to this embodiment. In FIG. 3, reference numerals 31, 41, 51 denote partner station addresses, 32, 4
2, 52 are priority flag areas, 33, 43, 53 and 45 are block numbers, while 33 and 45 are block numbers assigned by a station that creates and transmits text, and
3 and 53 are block numbers added to the text sent from the other station and received by us, 34 and 46
Is a transmission control character indicating the start of text, 35 and 47 is transmission text, 36 and 48 are transmission control characters indicating the end of text, 37 and 49 are block check codes or block check sequences, and 44 and 54 are from other stations. An acknowledgment or negative response to an information message sent and received by us.

In FIG. 2, the text created by the data processing unit 27 of the computer body is passed to the message management unit 26. The message management unit 26 classifies the created text for each destination of the terminal device, controls the sending order, and instructs the message sending unit 25 to send the text. It also controls the session. The message transmission unit 25 divides the text into transmission units (blocks) that can be transmitted at one time, and adds a block number (BSC) to each block. This block is arranged in the form of a message and is passed to the communication control unit 22. The communication control unit 22 assigns a block check code (BC
C) or a block check sequence (BCS) is added to transmit a code to the line equipment 21, or a code that arrives from the line equipment 21 is assembled into a block that can be processed by an electronic computer. The blocks assembled by the communication controller 22 are passed to the message receiver 23. The message receiving unit 23 assembles the blocks received from the communication control unit 22 into text units that can be data processed by the computer body, and passes the blocks to the message management unit 26.

The input / output control unit 25 controls the message receiving unit 22 and the message transmitting unit 23 to communicate with the partner station according to the basic data transmission control method, controls the detected error, and recovers the result of the recovery process. Is notified to the message management unit or the OS, the command is operated by the OS, and the notification is returned.

Next, the operation of the embodiment of priority control positioned in the input / output control unit 24 according to the present invention will be described with reference to FIG. First, in step 11 shown in FIG. 1, a failure notification from the input / output control unit 24 is waited for. If there is a failure notification, it is checked in step 12 whether or not it is the same as the BSC added to the text sent from the own station, and if they are the same, it is determined that there is a BSC collision. If it is not a collision, control is passed to the error controller as a failure notification not related to the present invention. What is determined to be a BSC collision in step 12 is passed to step 13. At step 13, it is judged whether the own station is a priority station or a non-priority station. If the own station is a non-priority station, in step 16, the error control unit sets a command to control the start of the no-response timer, and passes control to the error control unit. That is, the non-priority station expects the priority station to retransmit the text and performs timer monitoring. If it is retransmitted within the specified time, it will be received and processed. If it is not retransmitted within the specified time, the non-priority station retransmits the transmission. In step 13, if the own station is the priority station,
In step 14, the priority flag is set to ON (or OFF). In step 15, a command is set to perform retransmission control by error control, and control is passed to the error control unit. A message with a priority flag set must be processed with priority even when the same BSC collides.

[0010]

As described above, according to the basic type data transmission control method of the present invention, it becomes possible to promptly send the information message by judging whether the own station is the priority station, and the information to the other station is sent. You can surely communicate and exchange information with the other station.

[Brief description of drawings]

FIG. 1 is a flowchart showing an example of an operation in a basic data transmission control system of the present invention.

FIG. 2 is a block diagram showing an embodiment of a basic data transmission control system of the present invention.

FIG. 3 is a diagram showing an example of the configuration of a message and a monitoring sequence used in the basic data transmission control method of the present invention.

[Explanation of symbols]

 21 line equipment 22 communication control unit 23 message receiving unit 24 input / output control unit 25 message transmitting unit 26 message managing unit 27 data processing unit

Claims (1)

[Claims] 1. In a data transmission control procedure of a point-to-point system performed between data terminal devices or data processing devices connected by a transmission line, a priority flag area is held in a transmitted message or a monitoring sequence. An ON or OFF state is set in the area of the priority flag, and a step of judging the same collision of the block numbers (numbering system such as cyclic number or sequence number) attached to the message or the monitoring sequence. A basic type data transmission control method comprising: a step of judging whether the own station is a priority station; and a step of setting the priority flag to ON or OFF in a message to be transmitted or a message to be retransmitted.