JP2005167872A - Can bus measuring instrument - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a CAN bus measuring instrument in which a temporal relationship of a data frame flowing on a CAN bus and an error frame on a time base can be visually grasped from the same display screen. <P>SOLUTION: The CAN bus measuring instrument for measuring CAN frames flowing on the CAN bus and for displaying results of the measurements is comprised of a means for also collecting error frames together with the data frames; a means for converting these data frames and error frames into time-sequential data; and a means for displaying these time-sequential data on the same screen. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a CAN bus measuring apparatus, and more particularly to display processing of a data frame and an error frame.

  Patent Document 1 relates to a CAN (Controller Area Network), and there is a technique for preventing a bus from being occupied by an abnormal node and performing communication from another node when an abnormality occurs in a communication line. is described.

  Patent Document 2 also relates to a CAN bus, and describes a technology that enables the CAN bus to be used in the field of avionics (avionics).

JP 2002-359625 A JP 2003-198572 A

  The present invention measures CAN frames flowing through such a CAN bus and displays the measurement results. In any of these patent documents, a signal frame transmitted through the CAN bus is measured. There is no description about displaying the measurement results.

  The CAN bus is a serial bus that connects sensors and actuators in a lower layer of the network system, and is being adopted as a standard for in-vehicle LANs in various countries around the world. In addition to the control of automobile equipment, it also meets very high safety standards in fields such as industrial equipment such as FA (Factory Automation) and medical equipment that requires safety and reliability. Adoption is progressing.

  FIG. 5 is a block diagram showing an example of a measurement apparatus that collects frame data on a conventional CAN bus. The CAN frame data receiving device 1 receives a CAN frame flowing on the CAN bus 2 and sends it to the data frame resampling device 3 if the received CAN frame is a data frame, and sends it to the error processing device 4 if it is an error frame. Here, the CAN frame flows on the CAN bus in a bit rate range of 10 KHz to 1 MHz, for example. Whether a CAN frame is a data frame or an error frame is determined by whether each received CAN frame satisfies a predetermined standard.

  The resampling device 3 performs resampling processing on the sent data frame to create time-series data of CAN data. Then, the created time-series data of the CAN data is displayed on, for example, the waveform display 5, stored in the data storage device 6, and analyzed by the data analysis device 7. The resampling device 3 performs resampling with a period of, for example, 1 ms to 1H.

  The error processing device 4 interprets the content of the error frame and leaves the result in the error log 8 as a history. Further, the error processing device 4 increases the count value of the error counter 9 by one count every time an error frame is received.

  FIG. 6 is an example in which time-series data of 2-channel CAN data collected by the apparatus of FIG. 5 is represented in a tabular form. FIG. 7 shows the time-series data shown in FIG. It is a display example of a waveform. FIG. 8 is a display example of a dialog that displays a list of logs of errors that have occurred on the CAN bus 2 while collecting the time series data of FIG.

  According to these display screens of FIG. 7, the waveform of the CAN data of the two channels CH1 and CH2 flowing through the CAN bus 2 and the mutual time relationship can be grasped. According to the display screen of FIG. 8, the CAN data displayed in FIG. You can know the number, type, and order of errors that occurred during collection.

  However, with such a conventional configuration, the temporal relationship on the time axis between the data frame flowing through the CAN bus 2 and the error frame cannot be recognized simultaneously on the same screen.

  The present invention solves such a conventional problem. The purpose of the present invention is to visualize the temporal relationship between both frames on the time axis for the data frame and error frame flowing through the CAN bus from the same display screen. It is to provide a display device that can be easily grasped.

In order to achieve such a problem, the invention according to claim 1 of the present invention is:
In a CAN bus measurement device that measures CAN frames flowing through a CAN bus and displays the measurement results,
Means for collecting error frames along with data frames;
Means for converting these data frames and error frames into time-series data;
Means for displaying these time-series data on the same screen,
It is characterized by comprising.

The invention according to claim 2 is the CAN bus measuring device according to claim 1,
The error frame is displayed at each error occurrence position with a pulse waveform having a different height for each type of error.

The invention described in claim 3 is the CAN bus measuring device according to claim 1,
The error frame is displayed at each error occurrence position with a pulse waveform of a different color for each type of error.

According to a fourth aspect of the present invention, in the CAN bus measuring device according to the first aspect,
The error frame is displayed at each error occurrence position with a character symbol indicating the type of error.

The invention according to claim 5 is the CAN bus measuring device according to claim 4,
The display form of the character symbol indicating the type of error is varied depending on the type of error.

A sixth aspect of the present invention is the CAN bus measuring device according to the fifth aspect,
The display form of the character symbol indicating the type of error is at least one of color and shape.

  According to these aspects of the present invention, it is possible to visually grasp the temporal relationship between both frames on the time axis for the data frame and the error frame flowing through the CAN bus from the same display screen, and efficiently analyze the cause of the error. be able to.

  Hereinafter, the present invention will be described in detail with reference to the drawings. FIG. 1 is a block diagram showing an embodiment of the present invention, and the same reference numerals are given to portions common to FIG. The difference between FIG. 1 and FIG. 5 is that the CAN frame data receiving apparatus 1 receives a CAN frame flowing on the CAN bus 2 and the data frame regardless of whether the received CAN frame is a data frame or an error frame. It is output to the resampling device 3.

  The resampling device 3 performs resampling processing on the data frame transmitted from the CAN frame data receiving device 1 to create time-series data of CAN data.

  Further, the resampling device 3 also performs resampling processing on the error frame sent from the CAN frame data receiving device 1, and creates an error channel as an element constituting time-series data of CAN data.

  Here, the type of error is determined for each error frame, and a display form capable of identifying the type is set for each error frame. Specifically, the height of the pulse, the display color of the pulse waveform, the number of the character symbol, or the display form number of the character symbol display color and shape are changed. Make them different.

  The time-series data of CAN data including the error channel created in this way is displayed on, for example, the waveform display 5, stored in the data storage device 6, and analyzed by the data analysis device 7. The resampling device 3 performs resampling with a period of, for example, 1 ms to 1H, as in the prior art.

  FIG. 2 shows time-series data in which the 2-channel CAN data CH1 and CH2 collected by the apparatus of FIG. 1 and an error number indicating the type and content of the error frame generated in association with them are arranged as the third channel CH3. It is an example expressed in a format. The value “0” of the third channel CH3 indicates that no error has occurred, and the other values indicate that an error frame of the type assigned with each error number has occurred.

  FIG. 3 is a waveform display example in which the time series data shown in FIG. In the display screen of FIG. 3, the bottom pulse train represents the generation of an error frame as the third channel CH3. The position of each pulse on the horizontal axis (time axis) indicates the time when the error occurred, and the height of each pulse corresponds to an error number indicating the type and content of the error frame. If the lowest pulse is error number 1, the middle height pulse is error number 2, and the highest pulse is error number 3, the error frame err1, err2, and err5 had error number 3 error. Thus, the error frame err3 indicates that the error number 3 error has occurred, and the error frames err4 and err6 indicate that the error number 1 error occurs.

  According to the display screen of FIG. 3, the temporal relationship between both frames on the time axis can be visually grasped from the same display screen for the data frame and the error frame flowing through the CAN bus. Note that the type and content of the error frame can be more intuitively identified by changing the display color of each pulse for each pulse height.

  FIG. 4 is also a waveform display example in which the time series data shown in FIG. In the display screen of FIG. 4, a small arrow is displayed at the position where each error frame is generated at the bottom of the waveform display area, and an error number indicating the type and content of the error frame is displayed below each arrow. According to the display form of FIG. 4, the type and content of the error frame can be directly known from the error number without reading the error number from the level of the pulse as shown in FIG. It should be noted that the error frame type and contents can be more intuitively identified by changing the color and shape of the arrow representing the error frame occurrence position in FIG. 4 and the display form of the error number according to the type of error. Become.

  As described above, according to the present invention, regarding the data frame and error frame flowing through the CAN bus, the temporal relationship between both frames on the time axis can be visually grasped from the same display screen, and the cause of error occurrence can be analyzed. Can be performed efficiently.

It is a block diagram which shows one Example of this invention. It is the example which represented the time-sequential data based on this invention in the tabular form. It is an example of a display screen based on this invention. It is another example of a display screen based on this invention. It is a block diagram which shows an example of the conventional CAN bus measuring apparatus. . It is an example of a tabular display of time series data in a conventional CAN bus measuring device. It is an example figure of the conventional display screen. It is a display example of a conventional error log list display dialog.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 CAN frame data receiver 2 CAN bus 3 Resampling device 5 Waveform display 6 Data storage device 7 Data analysis device

Claims (6)

In a CAN bus measurement device that measures CAN frames flowing through a CAN bus and displays the measurement results,
Means for collecting error frames along with data frames;
Means for converting these data frames and error frames into time-series data;
Means for displaying these time-series data on the same screen,
A CAN bus measuring device comprising:   2. The CAN bus measuring apparatus according to claim 1, wherein the error frame is displayed at each error occurrence position with a pulse waveform having a different height for each type of error.   2. The CAN bus measuring apparatus according to claim 1, wherein the error frame is displayed at each error occurrence position with a pulse waveform of a different color for each type of error.   2. The CAN bus measuring apparatus according to claim 1, wherein the error frame is displayed at each error occurrence position with a character symbol representing an error type.   5. The CAN bus measuring device according to claim 4, wherein a display form of the character symbol indicating the type of error is varied according to the type of error.   6. The CAN bus measuring device according to claim 5, wherein a display form of the character symbol indicating the type of error is at least one of color and shape.

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