JPS6239939A - Line diagnosis device - Google Patents

Abstract

PURPOSE:To easily measure the delay time between frames or characters of a special pattern by duplexing a trigger detection function for the special pattern to detect from the transmission/reception data flowing through an interface. CONSTITUTION:The two kinds of trigger patterns set in reference data registers 9 and 10 by a main CPU 8 and that transmitted from a data fetching part 7 are compared by comparator logics 11 and 12, and in case they coincide with each other, a detection of trigger is informed to a sequence control logic 13. The main CPU 8 receives a first trigger interruption from the logic 13, and starts a timer, but stops it when receiving a second trigger interruption. And accordingly, the CPU 8 can measure the delay time between the frames or characters set by two trigger conditions.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a line diagnostic device used to perform protocol tests, communication failure tests, performance evaluations, etc. in data communication equipment.

(Prior art) Conventionally, a modem and communication control system that communicates using an independent synchronization method or a start-stop synchronization method is based on the "interface between a modem and a communication control device and a data terminal device" specified in C-6361 of the Japanese Industrial Standard. A line diagnostic device that connects each device by a signal flowing through the interface with the device or the interface between the modem and the data terminal device is a device that connects each device by a signal flowing through the interface between the data terminal device (hereinafter referred to as DTE) and the communication control device (hereinafter referred to as DCE). By connecting the signal, you can monitor the signal flowing through the interface without disturbing it in any way, display it on the screen of a cathode ray tube (hereinafter referred to as CRT), or trigger a specified bisonto column. You can stop the monitor or import data into memory.

Figure 4 shows the configuration of a conventional line diagnostic device.
Interface unit 1 inserted between E and DCE
The framing circuit 2 receives frames from the transmitted data and received data flowing in the frame, and
The data is stored in the data capture memory 3. Then, all the data of this frame is transferred to the CRT control circuit 4 which has a built-in video RAM, and the signal on the line is displayed on the screen of the CRT 5. Also, when a trigger is applied to the bit string specified by the key stroke, , the aforementioned monitor device iU is stopped, but if the signal flowing through the interface matches a pre-specified bit string, the trigger function is activated and a protocol test etc. can be performed.

(Problem to be solved by the invention) However, when a frame or character of a specific turn is detected from the signal flowing through the interface, the monitor function is simply stopped. If so, specify/
? There was a problem in that it was not possible to measure the frame of a turn or the delay time between characters.

The present invention was made to solve such problems, and an object of the present invention is to provide a line diagnostic device that can easily measure the delay time between frames or characters of a specific/F turn.

(Means for Solving the Problem) The present invention duplicates the trigger detection function of a specific turn for transmission data and reception data flowing through an interface, so that the delay time between both frames or characters can be measured. .

(Operation) Transmit data from the DTE and receive data from the DCE are passed through the trigger detection circuit, and when a pre-specified first bit string is detected, timing is started, and when a pre-specified second bit string is detected. By stopping the time measurement at , the time between specified frames or characters can be measured.

(Example) Fig. 1 shows the configuration of an embodiment of the present invention, Fig. 2 is a specific example for supplementary explanation of Fig. 1, and Fig. 3 (,)
shows the connection system of DTE and DCE, and Fig. 3(b) shows the connection system of DTE and DCE.
CP when a line diagnostic device is connected between TE and DCE
Execute the trigger function processing specified by U8. At that time, the trigger function itself can be processed by the μm CPU, but
Since high speed is required, this is achieved using discrete logic. Then, the two types of trigger patterns set in the reference data registers 9 and 10 by the main CPU 8 and the data transferred from the data acquisition unit 7 are compared by the comparator logics 11 and 12, and if they match, the sequence control is performed. Logic 13 is notified of trigger detection. Then, sequence control logic 1
3 manages the trigger detection signals notified from the comparator logics 11 and 12, and sequentially generates trigger detection interrupts to the main CPU 8. Further, the sequence logic 13 transfers the data transferred from the reception data stack 14 to the puncture control CPU 15, and stops data transfer to the puncture control CPU 15 when the second trigger is detected.

Furthermore, by stopping the timer using the sequence control logic, the main CPU 8 can measure the delay time between two trigger condition setting frames or characters. The concept of trigger interrupt processing by the main CPU 8 is as shown in FIG.

As described above, according to this embodiment, by using the two types of trigger patterns set by the main CPU 8, the delay time between both frames or characters can be instantaneously measured without using an external measuring device.

(Effects of the Invention) As explained above, according to the present invention, DTE and DEC
Since trigger detection can be performed for two specified frames or characters in the signal flowing through the interface between the two, it is possible to measure the delay time between the two specified frames or characters.

[Brief explanation of the drawing]

Figure 1 is a block diagram of one embodiment of the present invention, Figure 2 is a conceptual diagram of interrupt processing, and Figure 3 (a) is a diagram of DTE and DCE.
FIG. 3(b) is a diagram showing a connection system for connecting a line diagnostic device between a DTE and a DCE, and FIG. 4 is a block diagram of a conventional line diagnostic device. 7... Data import unit, 8... Main CPU, 12.
...Comparator logic.

Claims (1)

[Claims] A line diagnostic device that is connected to each device by a signal flowing through the interface between the modem and the communication control device or the interface between the modem and the data terminal device synchronizes with the data transmitted from the data terminal device and analyzes frames or means for receiving characters; means for receiving frames or characters in synchronization with data received from a communication control device; and means for detecting that a pre-specified bit string is present in a transmitted frame or received frame. Then, when a pre-specified first bit string is detected in the transmitting frame or the receiving frame, timing is started, and when a pre-specified second bit string is detected, timing is stopped, thereby controlling the signal flowing through the interface. 1. A line diagnostic device comprising: means for measuring a delay time between specified frames or characters in transmitted data or received data.