KR100261028B1 - Structure of protocol between tcu and terminal - Google Patents

Abstract

PURPOSE: A structure of a protocol between a TCU(Terminal Control Unit) and a terminal and its method are provided so that complete data transmission can be achieved by performing data transmission between the TCU and the terminal in an asynchronous transmission mode using RS-232C connection, and by cross-checking a data message and an ACK message. CONSTITUTION: A data is transmitted/received between a TCU and a terminal according to an asynchronous transmission mode using RS-232C connection. Here, the TCU controls the terminal between the terminal and a host computer. A data message for transmitting the data and an ACK message for transmitting the data message without an error are cross-checked. The data message includes control bytes and data bytes. The data bytes compose a data field and the control bytes compose a header. The ACK message includes a message type field, a sequence field, an oxFF field, a brake field and an error code field. In order to distinguish consecutively-transmitted or received message units, a brake signal is added. Due to the complete data transmission, the user can perform a telephone access to the host computer through a telephone line by using a modem. In addition, the user can use his/her terminal regardless of distance. When the user moves to a different place, if the user needs to use the host computer, he/she can access to the host computer through a modem of a general computer. As a result, the user can conveniently use the protocol structure in any place.

Description

Protocol structure between TC and terminal and its processing method

The present invention relates to a protocol structure between a UE and a terminal and a processing method thereof, and more particularly, data transmission and reception between a terminal control unit and a terminal serving as a controller for controlling the terminal between the terminal and the host computer. Is performed asynchronously by RS-232C connection, but cross-checks data message to transmit data and ACK message to enable data message transmission without error. The present invention relates to a protocol structure between a TCU and a terminal which can be accessed through a terminal and can use a terminal without a distance limitation, and a processing method thereof.

When the data is stored in a large computer such as IBM and FACOM, and the data is retrieved and input from a large computer using a terminal from a remote location, the place where the terminal is to be installed is widely distributed. In order to connect and use a large number of terminals 14, a controller called a TCU (12, Terminal Control Unit) is used to control a plurality of terminals 14 between the terminal 14 and the host computer 10. use.

Conventionally, the TCU 12 and the terminal 14 are connected by using a coaxial cable.

In this case, data transmission is accurate, but there is a limit of distance.

In particular, since the modem cannot be connected, the TCU 12 must be installed remotely in order to use the host computer 10 remotely. However, since the TCU 12 equipment is expensive, every remote site regardless of the number of terminals 14 It was impossible to install.

With this in mind, when using the host computer 10 at a remote location, the connection between the TCU 12 and the terminal 14 is generally used for communication, and MODEM usage is generally used so that only the terminal 14 can be used at a remote location. Asynchronous RS-232C is now available.

In case of using coaxial cable, there is no loss in data transmission, which provides high reliability.However, RS-232C asynchronous communication method is less reliable, especially when connected via telephone line using MODEM. There was a problem.

In order to solve the above problems, a communication protocol between the TCU and the terminal is devised. The present invention provides an asynchronous method for transmitting and receiving data between a terminal control unit (TCU) and the terminal through an RS-232C connection. Cross-check the data message to transmit the data and the ACK message to transmit the data message without error. The perfect data transmission is possible. You can use the modem to connect through the telephone line. The purpose of the present invention is to provide a protocol structure between the TCU and a terminal and a processing method thereof.

In order to achieve the above object, the present invention is composed of an asynchronous RS-232C connection between the TCU and a plurality of terminals, a data message for data transmission and an ACK message for enabling data transmission without errors;

The data message;

In the 1-byte message type field that determines how to process input data, a 1-byte device field that indicates the port number of the terminal connected to the TCU, a 1-byte sequence field that indicates the frame order to be transmitted and received, and a message type field. A one-byte check thumb field used to determine whether there is an abnormality in the transmission / reception data by XORing the code to the data field, and a one-byte flag and session field indicating the connection status and transmission / reception status of the host computer and the terminal. A 1-byte lance field indicating the number of bytes from the message type field to the data field, a 1-byte RH0 field with a header number of 0 for the request / response unit, and 1 byte for a header number of 1 for the request / response unit. Terminal to distinguish the RH1 field, the n-byte data field, and the message unit to be transmitted and received A break field used when sending data from the TCU to a TCU or an oxFF field of 1 byte used when sending data from the TCU to the terminal;

The ACK message is

1 byte message type field for determining input data processing method, 1 byte error code field indicating whether there is an error for data to be transmitted and received, 1 byte sequence field indicating frame order to be transmitted and received, and message type field A break used to send data from the terminal to the TCU in order to distinguish between a check byte field of 1 byte used to determine whether there is an abnormality in the transmission / reception data by XORing a code from the checksum to the check thumb. It is intended to provide a protocol structure between a TCU and a terminal, which is configured in the order of a 1-byte oxFF field used when sending data from a field or a TCU to a terminal.

In order to achieve the above object, the present invention performs a data transmission and reception between the TCU and the terminal in an asynchronous manner by the RS-232C connection, the data message for transmitting the data and the ACK message that enables the transmission of the data message without errors The present invention provides a protocol processing method between a TCU and a terminal, which includes sending a break signal at the end of a message in order to cross check each other and distinguish message units continuously transmitted and received.

1 is a network configuration to which the present invention is applied,

2A and 2B are structural diagrams of messages of a protocol according to the present invention;

3 is a protocol flow diagram of FIGS. 2A and 2B;

4A and 4B are structural diagrams of messages of a protocol according to another embodiment of the present invention;

5 is a protocol flow diagram of FIGS. 4A and 4B.

<Description of the symbols for the main parts of the drawings>

10: host computer, 12: TCU, 14: terminal, 20: data message, 21, 41: message type, 22: device, 23, 43: sequence, 24, 44: check thumb, 25: flag and session, 26: Lance, 27: RH0, 28: RH1, 29: Data, 30, 45: Brake, 31: Lance High, 32: Lance Low, 34,46: oxFF, 35, 47: Header, 40: ACK Message, 42: Error code.

Hereinafter, the present invention will be described with reference to the accompanying drawings, FIGS. 2 to 5.

2A and 2B are message-specific structure diagrams of a protocol according to the present invention, FIG. 3 is a protocol flow chart of FIGS. 2A and 2B, and FIGS. 4A and 4B are message-specific structure diagrams of a protocol according to another embodiment of the present invention. 5 is a protocol flow diagram of FIGS. 4A and 4B.

First, referring to the structure of the protocol, which is a basic configuration of the present invention, the TCU 12 and the plurality of terminals 14 are connected by an asynchronous RS-232C, and the data message 20 for data transmission and data without errors. An ACK message 40 to enable transmission;

(I) the data message 20;

(Iii) a one-byte message type field 21 for determining a method of processing data to be input, (ii) a one-byte device field 22 indicating a port number of a terminal 14 connected to the TCU 12; (I) XOR of the code of the 1-byte sequence field 23 indicating the frame order to be transmitted / received and (i) the message from the message type field 21 to the data field 29 determines whether there is an abnormality in the transmitted / received data. A check byte field 24 of one byte to be used in case of use, (i) a one byte flag and session field 25 indicating a connection state and a transmission / reception state of the host computer 10 and the terminal 12, (Iii) a one-byte lance field 26 representing the number of bytes from the message type field 21 to the data field 29, and (iii) a one-byte RH0 field with a header number of zero for the request / response unit. 27) and (iii) one-byte RH1 header with a header number of 1 for the request / response unit. A break field 30 is used to send data from the terminal 14 to the TCU 12 in order to distinguish between the code 28 and the (i) n-byte data field 29 and (i) the message unit to be transmitted and received. Or a 1-byte oxFF field 34 used when sending data from the TCU 12 to the terminal 14;

(II) the ACK message 40;

(Iii) a one-byte message type field 41 for determining a method of processing data to be input, and (ii) a one-byte error code field 42 as a value representing the presence or absence of an error for data to be transmitted and received, In the case where abnormality of transmission / reception data is judged by XORing the code of the 1 byte sequence field 43 indicating the frame order to be transmitted / received and the code from the message type field 41 to the check thumb field 44 The break field 45 or the TCU 12 used to transmit data from the terminal 14 to the TCU 12 in order to distinguish between a check byte field 44 of one byte and a message unit to be transmitted and received. In the order of one byte of the oxFF field 46 which is used when sending data to the terminal 14;

It features.

Hereinafter, the present invention will be described in more detail. The TCU 12 and the plurality of terminals 14 are connected by asynchronous RS-232C and enable data transmission without error with the data message 20 for data transmission. The protocol consists of an ACK message 40.

The data message 20 consists of a control (control) byte and data bytes, the data byte making up the data field 29 and the control byte making up the remaining field, a header.

The message type field 21 is a command for determining a method of processing data to be input. The size is 1 byte (8 bits), and the device field 22 is a port number of the terminal 14 connected to the TCU 12. It is also 1 byte.

The Sequence field 23 is 1 byte indicating the frame order of the protocol to be transmitted and received, and the Check Sum field 24 is obtained by XORing the code from the message type field 21 to the data field 29. The value is used to determine whether there is an abnormality in transmission / reception data and is 1 byte.

The flag and session fields 25 indicate a session indicating a connection state between the host computer 10 and the terminal 14 in use, and send / receive between the host computer 10 and the terminal 14 in use. It is composed of a flag indicating a status and is one byte. The length field 26 is one byte indicating the total number of bytes from the message type field 21 to the data field 29.

The RH0 field 27 is 1 byte in which the header number of the request / response unit is 0, and the RH1 field 28 is 1 byte in which the header number of the request / response unit is 1.

The data field 29 is n bytes having data such as a screen, a print, a status, and the like.

The break field 30 is used to transmit data from the terminal 14 to the TCU 12 in order to distinguish the transmitted and received message units, and the oxFF field 34 is used to transmit data from the TCU 12 to the terminal 14. One byte is used.

In the case of the oxFF field 34, the first ox represents a hexadecimal number and the second FF represents a number.

Among the following ACK messages 40, the message type field 41, sequence field 43, oxFF field 46 and break field 45 are weak as described above in the data message 20, and the error code field 42 is transmitted and received. 1 byte indicating the presence or absence of data error.

The check thumb field 44 is a value obtained by XORing a code from the message type field 41 to the check thumb field 44, and is one byte used to determine whether there is an abnormality in transmission / reception data.

In the protocol processing method configured as described above, data transmission and reception between the TCU 12 and the terminal 14 is performed asynchronously by an RS-232C connection, but the data message 20 for transmitting data and the data message without error ( Figure 3 is a flow chart as seen from the terminal characterized in that the cross-check the ACK message 40 to enable the transmission of 20) and to add a break signal at the end of the message to distinguish the message unit that is continuously transmitted and received.

When the message transmission of one frame is completed, processing starts and a check thumb is performed first.

If an error occurs in the check thumb, the number of transmitted / received bytes is larger than the standard number of bytes (XByte), so if it is a data message 20, the data message 20 is sent to be retransmitted. .

If it is smaller than or equal to ACK message 40, the ACK message 40 is transmitted to be retransmitted, and then the break signal is transmitted and then terminated.

If there is no error in the check thumb, check whether it is a restart message (the first message connected and sent) that is one of the message types, and if it is Yes, send an ACK restart, which is one of the message types, send the break signal, and then exit. In other words, if it is not a restart message, it is checked whether it is an ACK message 40.

If the ACK message 40 checks the lance, which is the number of bytes, and if there is an error, the control byte has an error. Therefore, a header error is transmitted, and then a break signal is transmitted and then terminated.

If there is no error in the lens, check the sequence that is the frame order and the error code to determine whether there is an error.If there is no error, process the ACK message and terminate.If there is an error, send the message that the ACK message is bad. Sends the brake signal and ends.

If the message type is not the ACK message 40, that is, the data message 20 is checked, and if the message type is wrong, the message type is an error. If the message types are the same, the device which is the port number of the terminal 14 and the sequence value which are the frame order are stored, and when the error code is not transmitted, the break signal is transmitted and the data message is processed to finish.

When finished, a message is transmitted one frame again, and the above-described flow is repeated to process the protocol.

As described above, cross-checking is performed between the data message 20 and the ACK message 40 so that data transmission can be performed without error, and a break signal is transmitted at the end of the message to distinguish a message unit that is continuously transmitted and received.

As another method for distinguishing message units that are continuously transmitted and received, message lengths 31 and 32 may be transmitted in the data message 20 so that the receiving side may divide the message in units of message lengths.

Referring to the structure of the protocol for realizing the above-described processing method, the header fields 35 and 47 of the data message 20 and the ACK message 40 in FIG. 4A and FIG. 4B are the data message 20 or the ACK message 40. It is 1 byte for determining whether or not, the lance high field 31 of the data message 20 is the value obtained by ORing a constant hexadecimal number from the high byte among the number of bytes from the lance high field 31 to the data field 29, The lance low field 32 is one byte in the low byte value in the number of bytes from the lance high field 31 to the data field 29.

Also, the oxFF fields 34 and 46 are 1 byte used only when data is sent from the terminal 14 to the TCU 12.

Other message type fields (21, 41), device fields (22), sequence fields (23, 43), check thumb fields (24, 44), flag and session fields (25), data fields (29), error codes The field 42 is weak as described above, except that the check thumb field 24 is a value obtained by XORing a code from the lance high field 31 to the data field 29.

FIG. 5 is a flowchart, which is different from FIG. 3 in that the start code is executed before the checksum, and whether the data message 20 or the ACK message 40 is distinguished.

In addition, it can be seen that a break signal is not transmitted to distinguish between message units continuously transmitted and received before termination.

Such a protocol processing method has an advantage that there is no problem due to the overlapping use of brake signals.

As described above, the present invention performs data transmission and reception between the TCU and the terminal in an asynchronous manner by an RS-232C connection, but cross-checks the data message for transmitting data and the ACK message for enabling data message transmission without error. This enables perfect data transmission, which can be accessed via a telephone line using a modem, and the terminal can be used without any distance limitation. It is a useful invention that can be conveniently used for mobile work such as local branches, agency management, telecommuting, insurance recruitment, etc. can be dialed.

Claims (4)

The TCU 12 and the plurality of terminals 14 are connected by an asynchronous RS-232C, and include a data message 20 for data transmission and an ACK message 40 for enabling data transmission without error; (I) the data message 20; (Iii) a one-byte message type field 21 for determining a method of processing data to be input, (ii) a one-byte device field 22 indicating a port number of a terminal 14 connected to the TCU 12; (I) XOR of the code of the 1-byte sequence field 23 indicating the frame order to be transmitted / received and (i) the message from the message type field 21 to the data field 29 determines whether there is an abnormality in the transmitted / received data. A check byte field 24 of one byte to be used in case of use, (i) a one byte flag and session field 25 indicating a connection state and a transmission / reception state of the host computer 10 and the terminal 12, (Iii) a one-byte lance field 26 representing the number of bytes from the message type field 21 to the data field 29, and (iii) a one-byte RH0 field with a header number of zero for the request / response unit. 27) and (iii) one-byte RH1 header with a header number of 1 for the request / response unit. A break field 30 is used to send data from the terminal 14 to the TCU 12 in order to distinguish between the code 28 and the (i) n-byte data field 29 and (i) the message unit to be transmitted and received. Or a 1-byte oxFF field 34 used when sending data from the TCU 12 to the terminal 14; (II) the ACK message 40; (Iii) a one-byte message type field 41 for determining a method of processing data to be input, and (ii) a one-byte error code field 42 as a value representing the presence or absence of an error for data to be transmitted and received, In the case where abnormality of transmission / reception data is judged by XORing the code of the 1 byte sequence field 43 indicating the frame order to be transmitted / received and the code from the message type field 41 to the check thumb field 44 The break field 45 or the TCU 12 used to transmit data from the terminal 14 to the TCU 12 in order to distinguish between a check byte field 44 of one byte and a message unit to be transmitted and received. In the order of one byte of the oxFF field 46 which is used when sending data to the terminal 14; Characterized in that the protocol structure between the TCU and the terminal. The method of claim 1, wherein the data message (20) is; (Iii) the header field 35, which is one byte for determining whether the data message 20 or the ACK message 40, and (ii) the high byte in the number of bytes from the lance high field 31 to the data field 29; A lance high field 31 having a value of OR of a fixed hexadecimal number, and a (1) lance low field having 1 byte as a low byte value from the number of bytes from the lance high field 31 to the data field 29. 32), (i) the message type field 21, (i) the device field 22, (i) the sequence field 23, and (i) the data field in the lance high field 31. The check thumb field 24, (i) the flag and session field (25), and (i) the data, which are used to determine whether there is an abnormality in transmission / reception data at a value obtained by XORing the code up to (29). Field 29 and (i) the oxFF field 34 used only when sending data from the terminal 14 to the TCU 12; The ACK message (40); (Iii) a header field 47 which is one byte for determining whether a data message 20 or an ACK message 40, (ii) the message type field 41, and (iii) the error code field 42; (Iii) the sequence field 43, (iii) the check thumb field 44, and (iii) the oxFF field 46 which is used only when sending data from the terminal 14 to the TCU 12. Consisting of the order of; Characterized in that the protocol structure between the TCU and the terminal. Data transmission and reception between the TCU 12 and the terminal 14 in an asynchronous manner by an RS-232C connection, but the data message 20 for transmitting data and the ACK message for enabling the transmission of the data message 20 without errors. A protocol processing method between the TCU (12) and the terminal (14), characterized in that cross-checking (40) with each other and adding a break signal at the end of the message in order to distinguish message units that are continuously transmitted and received. The method according to claim 3, wherein the message length is transmitted in a data message (20) to distinguish message units continuously transmitted and received instead of the break signal.