JPS61273040A - Line trace system - Google Patents

Abstract

PURPOSE:To facilitate the arrangement and the edition of the result of a trace by selecting whether all data on a communication line are traced and stored in a memory or only the frame having the set address is traced and stored in the memory so as to prevent a memory capacity from being increased and the memory from being expensive. CONSTITUTION:When an address collated by an address coincidence detection circuit 23 is a sender address, a data transfer control circuit 20 moves the destination address of a buffer 19 to a buffer 21, stores the sender address in the buffer 19, and the result is collated by the circuit 23. When not coincident, the contents of the buffers 19, 21 are cleared, and the operation restores to the detecting operation of a flag F or a preamble PA. When the said collation is coincident, the data transfer control circuit 20 sends the content of the buffer 21 to the memory 24 of a main control section 13, moves the content of the buffer 19 to the buffer 21 so as to store sequentially the data in the memory 24.

Description

[Detailed Description of the Invention] (Summary) In a device that traces data on a communication line, by making it possible to extract and trace only frames having a specified address, transmission of a certain terminal device or terminal control device To enable tracing of only data, received data, or transmitted/received data.

[Industrial application field]

The present invention relates to a device for tracing data on a communication line, and more particularly to a line tracing method that makes it possible to select data to be traced by determining an address in the data, or to trace all data.

With the spread of data processing systems, a plurality of terminal control devices are connected to a computer system via a communication line, and a plurality of terminal devices are connected to this terminal control device via a communication line. ) procedure to transfer data or build a LAN (Local Area Network) to connect multiple terminal devices on an equal level.
For example, data is increasingly being transferred using the CSMA/CD (carrier sense multiple access/collision monitoring) method.

In such data processing systems, if a certain terminal device or terminal control device malfunctions, a line tracing device is connected to the communication line to trace the data being transmitted in order to isolate the fault. , the obtained data is analyzed.

In this case, not only can all data be traced,
It is desirable to be able to select and trace only the data of the necessary terminal device or terminal control device.

[Conventional technology]

FIG. 3 is a diagram showing an example of a data transmission line based on the HDLC procedure.

A terminal control device 2 is connected to the computer system 1 via a communication line a, and terminal devices 3 to 5 are connected to the terminal control device 2 via communication lines a.

When checking the status of the terminal control device 2, the line tracing device 6 is connected to the communication line a and traces data.

For example, when checking the status of the terminal device 3, it is connected to a communication line as shown by the dotted line, and data is traced.

FIG. 4 is a diagram illustrating the frame structure of the HD LC procedure.

Data is transmitted over the communication line a or b in the form of frames as shown in FIG. That is, F is a flag for establishing synchronization,
A is the address of each terminal device, C is a control signal for various controls, the information part is data sent and received by the terminal device, and the FC code is a frame check sequence for error detection.

The line tracing device 6 traces all the data on the communication line a or b that is transmitted in these frame configurations,
Store in memory.

FIG. 5 is a diagram illustrating an example of a LAN.

Terminal devices 7 to 10 are connected to the communication line d, and each terminal device equally obtains communication rights and transmits data to a desired partner terminal device. The line tracing device 6 is connected to the communication line d and traces data.

FIG. 6 is a diagram illustrating the frame structure of the C3MA/CD system.

PA is a preamble for establishing synchronization, DA is a destination address indicating the destination, SA is a source address indicating the source, L
is a length indicating the length of the information section, the information section is data transmitted and received by the terminal device, and Fe2 is a frame check sequence for error detection.

The line tracing device 6 traces all the data transmitted on the communication line d in these frame configurations and stores it in the memory.

[Problem that the invention seeks to solve]

As mentioned above, since the conventional line tracing device 6 traces all the data transmitted over the communication line and stores it in the memory, the necessary data may overflow from the memory and disappear. .

■It takes time to organize and edit trace results.

■The device becomes expensive because the memory capacity needs to be increased.

(2) The configuration of the line tracing device changes depending on the size of the system connected to the communication line to be traced, that is, the number of terminal devices, etc.

There are other problems.

In view of these problems, the present invention aims to provide a line tracing method that can not only trace all data but also select and trace only the data of the necessary terminal device or terminal control device. The purpose is

[Means for solving problems]

FIG. 1 is a block diagram of the principle of the present invention.

Reference numeral 11 indicates a trace control unit for tracing data input through a communication line; 12 indicates an operation unit through which an operator inputs commands to the line tracing device; 13 indicates a main control unit that controls the entire line tracing device; and 14 indicates traced data. A display control unit 15 is a display unit that displays data, 16 is a printer control unit that prints traced data, and 17 is a printer that prints data.

The trace control unit 11 selects the address of the required terminal device or terminal control device according to the address instructed by the operator from the operation unit 12 via the main control unit 13 and the trace mode, and only data at the specified address is selected. The traced data is either traced and stored in the memory of the main control unit 13, or all data is traced and stored in the memory of the main control unit 13, and the main control unit 13 displays this traced data on the display unit 15.
The configuration is such that the information is displayed on the screen and printed on the printer 17.

[Effect]

By configuring as described above, it is possible to trace all data as in the past, or to extract and trace only the data of a desired terminal device or terminal control device.

That is, the frame structure of the HDLC procedure shown in FIG. 4 includes the address A of each terminal device, and the address C3 shown in FIG.
Since the frame structure of the MA/CD method includes the destination address DA and the source address SA, it is possible to trace only the transmission data of a certain terminal device or terminal control device, or to trace the transmission data of a certain terminal device or terminal control device. It becomes possible to trace only received data, or it becomes possible to trace only transmitted and received data of a certain terminal device or terminal control device.

〔Example〕

FIG. 2 is a block diagram of a circuit showing one embodiment of the present invention.

FIG. 2 is a detailed block diagram of the trace control unit 11 shown in FIG. 1. The main control unit 13 shown in FIG. Based on this, the trace control unit 11 is controlled, and an address is set in the address-number configuration circuit 23.
By setting the trace mode, you can instruct whether to trace all data or only the data at the set address.

Data input from the communication line is converted from a serial signal into a parallel signal by the S/P conversion circuit 18 and sent to the flag detection circuit 22 . When the flag detection circuit 22 detects the flag F or preamble PA, the data transfer control circuit 2o stores the flag F or preamble PA in the buffer 19.

If the next data is also flag F or preamble PA,
The flag F or preamble PA of the buffer 19 is sent to the buffer 21 and stored therein, and r? The operation of storing the first flag F or preamble PA in the buffer 19 is repeated.

If the next data is address A or destination address DA, it is stored in the buffer 19 and then the address match detection circuit 23
Verify with . If they do not match, the contents of buffers 19 and 21 are cleared and the process returns to flag F or preamble PA detection operation.

If the address checked by the address-number configuration circuit 23 is the source address SA, the data transfer control circuit 20 moves the destination address DA from the buffer 19 to the buffer 21,
The source address SA is stored in the buffer 19 and is checked by the address-number construction circuit 23. If they do not match, the contents of buffers 19 and 21 are cleared and the process returns to flag F or preamble PA detection operation.

If the above matching matches, the data transfer control circuit 20 sends the contents of the buffer 21 to the memory 24 of the main control section 13, transfers the contents of the buffer 19 to the buffer 21, and sequentially stores the data in the memory 24.

Under the control of the main control section 13, the data stored in the memory 24 is displayed on the display section 15 via the display control section 14 shown in FIG. 1, and is also sent to the printer 17 via the printer control section 16 and printed. .

When tracing all data, the data transfer control circuit 20 transfers all data input from the S/P conversion circuit 18 to the buffer 19 according to instructions from the address/number configuration circuit 23.
．． 21 and then stored in the memory 24.

〔Effect of the invention〕

As explained above, since the present invention can trace data by selecting only the necessary terminal device or terminal control device, there is no need to change the configuration of the line tracing device regardless of the scale of the system. It is possible to prevent data from overflowing and disappearing or from increasing the memory capacity and making it expensive, and it is possible to easily organize and edit trace results.

[Brief explanation of the drawing]

Fig. 1 is a block diagram of the principle of the present invention. Fig. 2 is a block diagram of a circuit showing an embodiment of the invention. Fig. 3 is a diagram showing an example of a data transmission line using the HDLC procedure. Fig. 4 is a diagram showing the HDLC procedure. 5 is a diagram illustrating an example of a LAN. FIG. 6 is a diagram illustrating a frame configuration of the C3MA/CD system. In the figure, 1 is a computer system, 2 is a terminal control device, 3 to 5.7
10 is a terminal device, 6 is a line tracing device, 11 is a trace control section, 12 is an operation section, 13 is a main control section, 14 is a display control section, 15 is a display section, 16 is a printer control section, 17
18 is a printer, 18 is an S/P conversion circuit, 19.21 is a buffer, 20 is a data transfer control circuit, 22 is a flag detection circuit, 23 is an address/number configuration circuit, and 24 is a memory. The principle of the sun and moon (soft diagram) 2 Rero 3 and HDL 04 + q- frame structure and 3 and 3 and 3 and 3 and 4 prisoners

Claims (1)

[Claims] A device for tracing data on a communication line, comprising: a collation means (11) for collating an address included in a frame constituting the data; and a memory storage based on the collation result of the collation means (11). a control means (11) for storing data, and a control means (11) for storing data;
By setting the trace mode and address in 11), you can select whether all data on the communication line is traced and stored in memory, or only frames with the set address are traced and stored in memory. A line tracing method featuring: