KR910003245B1 - Method for processing escape sequence in packet assembler/disassembler system - Google Patents

Abstract

The method detects the escape sequences while the esacpe character is received, and stops the transmission of echo mask and data temperarily unit the reception of the escape sequences is completed then the character array data of the escape sequences is transmitted in one packet and the echo service is maked. The method includes steps: (A) checking the escape character when the letter data is received; (B) storing the present pad variable in first and resetting it in second; (c) releasing the data trasmission restrictions and driving an escape timer for receiving the escape sequence; and (D) stopping the echo service to the escape sequences which are received during the driving period of the escape timer and assembling the sequences in one packet.

Description

How to handle escape sequences in pad systems

1 is a conventional data processing flow diagram.

2 is a hardware diagram of a pad system for carrying out the present invention.

3 is a software configuration diagram of a pad system for carrying out the present invention.

4 is an escape sequence processing flowchart according to the present invention.

* Explanation of symbols for main parts of the drawings

10: clock generator 20: central processing unit

30: decoder driving unit 40: decoder

50: timer 60: switch and LED

70: linear input / output unit 80: speed control unit

90: ROM 100: Backup RAM

110: RAM 120: Backup unit

The present invention relates to an escape sequence processing method in a pad system, and more particularly, to a method of processing character string data of an escape sequence by a driving clock.

In general, a PAD (Packet Assembler / Disassembler) system is a system that performs a packet network function for accommodating general terminals (non-packet terminals) that cannot transmit or receive data in the form of packets. It combines the data into a packet network, or conversely, it decomposes the packet received from the packet network, converts it into a string, and outputs it to the general terminal. In addition, an escape character refers to a string for performing a specific function by successive one or two or more characters represented by different codes from their own codes. In this case, the escape sequence refers to an escape character generated by the terminal to indicate special control information and one or more strings following the escape character. When the escape sequence character strings are detected, the pad system should collect them in the same packet and transmit them without echoing each of the character strings.

1 is a flowchart of a data processing in a conventional pad system, the operation of which is as follows.

First, the pad system receives data from the non-packet terminal in step A1, and then checks the state of variable 2 in step A2. The variable 2 is a variable for determining whether or not to echo the input data. The variable 2 does not echo when the pad variable "2" is in the reset state, and echoes only when the pad variable "2" is in the set state. Here, the echo service refers to a function of retransmitting the received data back to the non-packet terminal when receiving data from the non-packet terminal connected to the pad system. The non-packet terminal connected to the pad system includes a host terminal for transmitting a program and the like and a data terminal for transmitting data by an operator. At this time, if the non-packet terminal is a host terminal, the pad system does not perform an echo service on the received data, but in the case of a data terminal, the operator echoes the generated data back to the terminal and displays it on the monitor of the terminal. In this case, the pad variable "2" is a variable for determining whether or not there is an echo service, and sets the state of the pad variable 2 in advance according to the type of the non-packet terminal to perform a service operation.

Therefore, when the pad variable 2 is set in step (A2), the reception data is transmitted to the non-packet terminal again in step (A3) to perform an echo service, and when the pad variable "2" is in the reset state, the reception data is performed. Does not provide eco-services. After that, the pad system determines the presence or absence of the pad data transfer condition in step (A4), and proceeds to step (A5) to execute the data transfer service at the transfer condition and enters the step (A6) when it is not a transfer condition. Temporarily save the data. Here, the transmission condition of the pad system is when a certain time has elapsed since the reception of the last character data (if an idle timer has elapsed), when a data transmission character such as a carriage return key is received, or when a break signal is received. This is the case when a transition is made to a pad command state. In addition, the pad system limits the packet size to a certain size (standard 128 bytes). Even if the separate data transfer condition does not occur, the pad system transmits data when the pad size exceeds the packet size.

However, in the conventional pad system as described above, the escape sequence cannot be detected by processing the escape sequence in the same manner as the normal data. Therefore, if the packet size is exceeded in the middle of the multiple character strings coming into the escape sequence, it may be impossible to transmit the escape string by including the escape character string in the same packet. Acknowledgment could occur. In addition, when the pad variable "2" is set, the escape character inputted to perform a specific function also performs an echo service to the corresponding non-packet terminal, thereby causing confusion by echo service unnecessary data for packet assembly. .

Accordingly, an object of the present invention is to provide a method for detecting an escape sequence in a pad system and assembling the escape sequence into the same packet.

It is another object of the present invention to provide a method in which an escape sequence may not be echo serviced to a corresponding non-packet terminal upon detection of an escape sequence.

Hereinafter, the present invention will be described in detail with reference to the drawings.

2 is a system diagram for carrying out the present invention, which includes a clock generator 10 for generating a clock signal, a central processing unit 20 for controlling a call and a system, and the central processing unit 20. A decoder driver 30 for controlling the signal from the decoder to de-live the decoder 40 to be described later, a decoder 40 for controlling various chips and I / Os by decoding logic, and the central processing unit 20. A timer 50 for generating an interrupt by a counting timer, a dip (DIP) switch for selecting a function of the system, a switch and an LED (60) indicating an error and whether the user is used, and the central processing unit (20) A serial input / output unit 70 for asynchronous and synchronous transmission of the non-packet terminal and character string data under control, a speed adjusting unit 80 for adjusting the transmission speed of the non-packet terminal under the control of the central processing unit 20, Save various programs of pad system The ROM 90 is used as a backup RAM 100 for storing data even when the system is powered off by storing the ROM 90, and a buffer for storing various flags and data generated during program execution. RAM 110 and a backup unit 120 for storing data of the backup RAM 110 even when the power off (power off). The configuration of the pad system as described above performs a function of assembling text data received from a non-packet terminal into a packet, transmitting the packet data to a packet network, and decomposing the packet received from the packet network to a packet terminal.

3 is a software configuration diagram of the pad system. The transmission and reception data processing modules (1, 2) and X.28 processing for performing data transmission / reception interface processing with an asynchronous terminal TERM1-TERM8 connected to the pad. Module 3, X.29 processing module 4, packet level processing module 5 for packet level processing, link level processing module 5 for link level processing, and terminal for processing packet level data Or a link transmission and reception processing module (7, 8) for performing data transmission / reception interface processing with the packet network.

In the above configuration, the transmission data processing module 1 processes data to be transmitted to the non-packet terminal, the reception data processing module 2 processes data received by the non-packet terminal, and the X.28 processing module 3 It handles the X.28 PAD Command and Service signals, and the X.29 Processing Module 4 processes the X.29 Pad messages from the other party during the call. The packet level processing module 5, which is a module implementing level 3, is a module implementing the X.25 level and is in charge of generation decomposition and flow control of packets. In addition, the link level processing module 6 is a module that implements X.25 level 2 and is responsible for link level data transmission and error control, and the link reception module 7 has a configuration of packet data through a packet terminal or a packet network. Receive processing of data frames, and the link transmission module 8 is responsible for the transmission of the data frames. In the above software configuration, the module for performing the process of the present invention is a reception data processing module (2).

4 is a flowchart illustrating an escape sequence process according to the present invention, which shows the first steps (B1, B2) of checking whether an escape character is received when receiving character data from the non-packet terminal, and the state of an escape character temporary echo service in the first step. A second process (B3) of resetting the pad variable after storing the current pad variable, and a third process (B4) of releasing the data transfer condition and driving an escape timer for receiving an escape sequence after performing the second process (B4). ), And stops the echo service for the escape sequence received within the escape timer driving period after the third process, and assembles it into a single packet, and when the completion of the escape timer is completed, the pad variable and the transmission are completed. A fourth process (B5) for restoring and returning a condition; A fifth process (B5, B6) which performs a set state temporary echo service according to the state of the pad variable at tile time and does not perform a reset state temporary echo service, and according to the state of data transmission condition after performing the fifth process A sixth process (B8-B10) is performed to assemble received text data into packets or to transmit and return packet data assembled into a packet network.

Based on the above configuration, the present invention will be described in detail with reference to FIGS.

First, when any terminal among the non-packet terminals TERM1-TERM8 generates text data, the CPU 20 reads the corresponding text data through the serial input / output unit 70 in step (B1), and then (B2). Check if the character data entered in Escape is an escape character.

In this case, when the received character data is an escape character, the process proceeds to step 33 to receive an escape sequence that is continuous string data in order to perform a specific function. The escape sequence is a string of bits used in a code determination procedure, and refers to a sequence of two or more sets of code combinations starting with an escape character to perform a specific function in a pad system. Therefore, after the escape character, a string of escape sequences is received in sequence, in which case no echo service is performed. Therefore, in step (B2), the received character data proceeds to step (B3), and temporarily stores the current pad variable 2 value indicating whether an echo service is present in RAM 110, and then character string data of the escape sequence. The echo pad is reset by resetting the pad variable 2 so that the echo service is not received.

Here, the pad variable 2 is a variable for determining whether there is an echo service for retransmitting the received text data to the corresponding non-packet terminal according to the type of the non-packet terminal. Therefore, if the pad variable 2 is set, the CPU 20 echoes data received through the serial input / output unit 70 back to the corresponding non-packet terminal. Then, the character data generated by the non-packet terminal monitor is displayed. However, since the escape sequence for performing a specific function is independent of the packet data, the operation of the echo service becomes unnecessary.

After resetting the pad variable 2 as described above, the CPU 20 releases the data transfer condition so that the CPU 20 cannot transmit the string data of the escape sequence until the string data of the escape sequence is completely received in step 84. ) To start the Escape Timer. As described above, in the pad system, assembling of text data is completed in the packet system, or a certain time has elapsed since the last text data is input, a data transmission character is received, a brake signal is received, a pad command is received. Occurs when transitions to. When the escape character is received, an escape sequence is received as a plurality of strings. In this case, if the above transmission condition occurs at the time of receiving the escape character, an error occurs because the packet is configured regardless of the escape sequence. Therefore, in step (B4), when the escape character is received, the transmission condition is released until all the string data is received so that the escape sequence can be collected and transmitted in one packet.

In addition, in step (B4), the escape timer is operated to set the reception time of the escape sequence. In this case, the escape timer operates as a driving clock for recognizing an escape sequence string character, and the character string input while the escape timer is running is regarded as an escape sequence to perform an escape sequence service. If no data is input until the escape timer has timed out, all escape sequence string characters are assumed to have been entered. For example, the driving time value of the escape timer may be set in units of 200 ms, that is, 200 ms × n (n = 1… 27).

Therefore, in the step (B5), it is checked whether the column character inputs to the escape timer driver's drive (within 200 ms). If the data is input within the escape timer driver's driving time, the character string data of the escape sequence is transferred to the RAM 110. The packet is collected and stored, and after restarting the escape timer to receive the next character data, the process returns to step (B1). If the data is not input within the driving time, the RAM sequence 110 is regarded as the end of the input of the escape sequence string character. The stored pad variable "2" is returned to its original position, and the released transfer data condition is restored. That is, in step (B5), the escape timer is driven, and while the escape timer is driven, the central processing unit 20 masks the echo service and collects the character data received in the escape sequence into one packet. If the character data is not received until the escape timer expires, it is determined that the reception of the escape sequence has been terminated, and the value of the pad variable 2 reset in the step (B3) is restored to the original state. At the same time, the transfer condition canceled in step 1 is controlled, and the timer 50 is controlled to stop driving the escape timer.

However, since the normal character data is not the escape character in the step (B2), the central processing unit 20 checks the state of the pad variable "2" value in the step (B6). At this time, when the pad variable 2 value is set in step (B6), the echo service is performed to the corresponding non-packet terminal in step (B7). In this case, the CPU 20 retransmits the received data through the serial input / output unit 70 to the corresponding non-packet terminal side, and thus the non-packet terminal and the monitor display the transmitted character data. However, when the pad variable 2 value is reset, no echo service is performed. Thereafter, the central processing unit 20 checks whether the data transfer condition is performed in step (B8). If the data transfer condition is not described above, the CPU 20 proceeds to step (B9) and stores the received text data in the RAM 110 in the form of a packet. . However, if it is determined in step (B8) that the data transmission condition (B10) in step (B10) and the character data assembled so far in the form of a packet through the serial input and output unit 70 to output the data transmission service.

As described above, the pad system detects an escape sequence upon receiving an escape character and pauses echo mask and data transmission until the escape sequence is completed, thereby collecting string data of an escape sequence in one packet. Echo service can be masked to the transmitting terminal at the same time, which can transmit and guarantee the escape sequence function of the transmitting and receiving side using the pad.

Claims (1)

A data processing method of a pad system for assembling text data generated from a non-packet terminal into a packet form, the method comprising: first steps (B1 and B2) of checking whether an escape character is received when receiving text data from the non-packet terminal; In the process, after storing the current pad variable indicating the state of the escape character temporary echo service, the second process (B3) of resetting the pad variable, and after performing the second process, cancels the data transmission condition and receives the escape sequence. The third process (B4) for driving the escape timer for the step, and the escape sequence received within the escape timer driving period after performing the third process, assembling into a single packet at the same time to stop the echo service, escaping when the escape timer is completed Restoring the pad variable and the transfer condition by ending reception of the sequence A fourth process (85), and a fifth process (B6, B7) which performs the set state temporary echo service according to the state of the pad variable at the time of the general character data and does not perform the reset state temporary echo service in the first process. And a sixth process (B8-B10) for assembling the received text data into packets or transmitting and returning the assembled packet data to the packet network according to the state of the data transmission condition after performing the fifth process. How to handle escape sequences in your system.

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