JP4385739B2 - Waveform measuring instrument - Google Patents

Description

The present invention relates to a waveform measuring apparatus that performs waveform observation by connecting modules each having one input channel, and more particularly to an improvement for enabling measurement of multi-channel data with one input module.
This input module is detachably connected to the waveform measuring instrument main body, and appropriately has various functions such as signal amplification, insulation, and filtering required according to the input signal, and the processed signal is transmitted to the waveform measuring instrument. It is comprised so that it can give to the main body side.

The Controller Area Network (CAN) protocol is a serial communication protocol standardized by ISO. Node [Electronic Control Equipment (ECU:
This is a serial communication protocol for communication between the Electronic Control Unit) and the sensors of each part. Conventionally, the CAN protocol has been used in connection with vehicles such as automobiles, but is now used not only in the automobile field but also in the medical and FA industries.

  The CAN protocol is a message-based protocol, where CAN frames are placed on a common CAN bus. The CAN bus may be a single wire or a pair of wires that are driven separately. A node on the common CAN bus receives each frame on the bus and filters out frames that are not necessary for the execution of the task of the node (see, for example, Patent Document 1).

  A system for observing data on a CAN bus using such a CAN protocol is known (for example, see Non-Patent Document 1). FIG. 3 is a configuration diagram of a system for observing data on a CAN bus by a waveform measuring device described in Non-Patent Document 1. In this system, a signal from each sensor 2 connected to the network 1, that is, a CAN data signal (for example, data such as throttle opening, rotation speed, speed, water temperature, etc.) is sent to the waveform measuring instrument 5 via the CAN bus 3. In the case of measuring by the above, an external CAN adapter 4 is necessary.

  The CAN adapter 4 appropriately selects sensor data and control signals of each part flowing on the CAN bus 3 and transfers them to the waveform measuring instrument 5 as observation data. The observation data is transferred from the CAN adapter 4 to the waveform measuring instrument 5 in a one-to-one relationship in which the waveform measuring instrument 5 has one input with respect to one output of the CAN adapter 4.

JP 2001-069179 A (second page) "CAN (Control Area Network) analysis system 8910 CAN adapter", [online], [October 24, 2003 search], Internet <URL: http://www.hioki.co.jp/jp/product/rec /8910.html>

However, the conventional system described in Non-Patent Document 1 has the following problems.
(1) An external CAN adapter is required for observing sensor data and control signals flowing on the CAN bus, and the CAN bus data must be converted to analog signals externally. In order to display the observation data on the measuring instrument, the analog signal must be input to the measuring instrument.
(2) Although this function can be put in the input module, the input of the input module is two, and only data on two CAN buses can be measured for one module. For this reason, if data of a large number of channels is to be observed, a plurality of modules are required, and at the same time, the CAN bus must be connected to the plurality of modules. In addition, wiring becomes complicated, and transmission and connection problems increase.

  SUMMARY OF THE INVENTION An object of the present invention is to solve such a problem. One input module monitors data from a line in which data is transferred serially such as CAN bus data, and uses a plurality of data as a plurality of channels. It is to provide a waveform measuring instrument that can be observed at the same time.

The present invention for achieving such a problem is as follows.
A waveform measuring instrument that reads a plurality of observation data flowing through a serial bus and displays a waveform, and stores the plurality of observation data in a buffer, and then sequentially stores the plurality of observation data and predetermined marker data on the waveform measuring instrument main body side. With input module to transfer to
On the waveform measuring instrument main body side, the marker data is detected from the data transferred from the input module, the plurality of observation data is extracted based on the marker data, and sequentially stored in the memory, and thereafter, the plurality of data is appropriately stored from the memory. Configured to be able to read out the observation data and display the waveform on the screen ,
The input module is
A plurality of buffers for storing the observation data;
A controller for analyzing the protocol of the serial bus and storing observation data of a preset ID number in a preset buffer among the plurality of buffers;
A selector for selecting marker data to be a unique code before observation data in a predetermined buffer when selecting observation data in order from each of the buffers and transferring the observation data to the waveform measuring device main body in a time-sharing manner;
Have
The waveform measuring instrument body is
It has a marker detection / selector unit that detects the marker data from the transferred data and stores them in a predetermined position in the memory in order from the observation data next to the marker data .

In this case, the serial bus is, for example, a CAN bus as described in claim 2.
The input module includes a CAN controller that analyzes a CAN bus protocol and stores observation data of a preset ID number in a preset buffer.
The transfer is serial transfer or parallel data transfer as in claim 4.

  As is clear from the above description, according to the present invention, a plurality of observation data is captured by the input module, and each observation data including marker data is transferred to the waveform measuring instrument main body side in a time-sharing manner. As a result, a plurality of data can be taken into the waveform measuring instrument by one input module and observed, and the effect is great for practical use.

Hereinafter, the present invention will be described in detail with reference to the drawings. In the embodiment, a case where six pieces of data on the CAN bus are observed simultaneously will be described as an example of the CAN observation data flow. FIG. 1 is a block diagram showing the principal part of an embodiment of a waveform measuring instrument according to the present invention.
In FIG. 1, 3 is a CAN bus, 10 is a CAN controller, 11a to 11f are buffers, 12 is marker data, 13 is a selector, 14 is a serial transmitter, 15 is a timing generator, and 16 is a marker detection and selector function. The marker detection / selector unit 17a-17f has a buffer, 18 is a memory controller, 19 is a memory, 20 is a graphic controller, and 21 is a display. The components from the CAN controller 10 to the serial transmitter 14 are components of the input module, and the components from the timing generator 15 to the display unit 21 are components on the waveform measuring instrument main body side.

The CAN controller 10 connected to the CAN bus 3 analyzes the CAN bus protocol, and stores observation data of a preset ID number in preset buffers 11a to 11f, respectively. For example, the observation data d1 with ID number 1 on the CAN bus is stored in the buffer 11a, and the observation data d2 with ID number 2 is stored in the buffer 11b.
This observation data is stored in the buffer asynchronously only when it matches six preset ID numbers.

  The observation data d1 to d2 stored in the six buffers are sequentially selected by the selector 13 in synchronization with the sampling signal from the timing generator 15 and sent to the serial transmitter 14. The serial transmitter 14 serially transfers the data to the marker detection / selector unit 16 on the apparatus main body side.

  FIG. 2 shows the sampling timing of the timing generator 15 (period T is, for example, 100 ksamples / second) and the timing of the observation data in the buffers 11 a to 11 f selected by the selector 13. The selector 13 sequentially transfers the observation data from each buffer to the serial transmitter 14 using the sampling timing. At this time, marker data (marker data) m is inserted between the transfer of data in the buffer 11f and the transfer of data in the buffer 11a.

  For example, the marker data is set to 8000h (h is a symbol indicating hexadecimal notation), and the observation data d1 to d6 stored in the buffer by the CAN controller 10 is set in advance to a value from 8001h to 7FFFh. Clip on the CAN controller 10 side. With this setting, the marker data 8000h becomes a unique code and can be distinguished from the observation data.

  The marker detection / selector unit 16 analyzes the transferred data in synchronization with the sampling timing of the timing generator 15. When marker data is detected, the observation data d1 next to the marker data is stored in the buffer 17a, the next observation data d2 is stored in the buffer 17b, and the observation data is sequentially stored in each buffer.

  The observation data d1 to d6 in the buffers 17a to 17f are stored in the memory 19 via the memory controller 18 at every sampling timing. For example, the observation data d1 is stored in the CH1 area, the observation data d2 is sequentially stored in the CH2 area, and the observation data from all the buffers is stored in all the channel areas from the CH1 area to the CH6 area of the memory 19.

  The observation data of all the channels stored in the memory 19 are displayed as waveforms of CH1 to CH6 on the screen of the display unit 21 under the control of the graphic controller 20.

  In this way, a plurality of data is fetched as a plurality of channels from one line such as CAN bus data, which is transferred serially, and is input from the input module to the waveform measuring instrument main body side by time division. Forward to. Thereby, a plurality of data can be observed with one input module.

In addition, this invention is not limited to the said Example, It includes many more changes and modifications.
For example, if a signal having a certain protocol can be analyzed and converted into data, it can be applied to the present invention even if it is not CAN data.
Further, the number of channels per input module is not limited to six.

  Furthermore, a CPU or DSP may be used for marker detection. The data transfer between the input module and the waveform measuring instrument main body may be parallel data transfer instead of serial transfer.

It is a principal part block diagram which shows one Example of the waveform measuring device which concerns on this invention. It is a timing chart for operation explanation. It is a block diagram of the system which observes the data on a CAN bus with a waveform measuring device.

Explanation of symbols

3 CAN bus 10 CAN controller 11a to 11f buffer 12 marker data 13 selector 14 serial transmitter 15 timing generator 16 marker detection / selector unit 17a to 17f buffer 18 memory controller 19 memory 20 graphic controller 21 display unit

Claims (4)

A waveform measuring instrument that reads a plurality of observation data flowing through a serial bus and displays a waveform, and stores the plurality of observation data in a buffer, and then sequentially stores the plurality of observation data and predetermined marker data on the waveform measuring instrument main body side. With input module to transfer to
On the waveform measuring instrument main body side, the marker data is detected from the data transferred from the input module, the plurality of observation data is extracted based on the marker data, and sequentially stored in the memory, and thereafter, the plurality of data is appropriately stored from the memory. Configured to be able to read out the observation data and display the waveform on the screen ,
The input module is
A plurality of buffers for storing the observation data;
A controller for analyzing the protocol of the serial bus and storing observation data of a preset ID number in a preset buffer among the plurality of buffers;
A selector for selecting marker data to be a unique code before observation data in a predetermined buffer when selecting observation data in order from each of the buffers and transferring the observation data to the waveform measuring device main body in a time-sharing manner;
Have
The waveform measuring instrument body is
A waveform measuring instrument comprising: a marker detection / selector unit that detects the marker data from the transferred data and stores the marker data in a predetermined position in the memory in order from observation data next to the marker data .   The waveform measuring instrument according to claim 1, wherein the serial bus is a CAN bus.   3. The waveform measuring apparatus according to claim 2, wherein the input module includes a CAN controller that analyzes a CAN bus protocol and stores observation data of a preset ID number in a preset buffer. .   4. The waveform measuring instrument according to claim 1, wherein the transfer is serial transfer or parallel data transfer.

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