JPH087752Y2 - Pulse data transmission indicator - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial application] The present invention relates to a transmission indicator for transmitting pulse data in a serial transmission format and displaying the pulse data. In particular, the present invention relates to a data transmission indicator suitably used to transmit and display pulse data to a diagnostic device for diagnosing the operation of a microcomputer system for inputting and controlling pulse data.

[Prior Art] When transmitting pulse data in a serial transmission format, accurate pulse data can be transmitted if the transmission cycle can be made smaller than the minimum value of the cycle in which the pulse data changes. However, it often happens that the transmission cycle cannot be made smaller than the minimum value of the change cycle. In particular, this often occurs when the microcomputer system is performing control based on pulse data and the pulse data is transmitted to another system, for example, a diagnostic unit of a microcomputer, within a range not hindering the control.

If pulse data is simply transmitted under such conditions, the data will not be sent correctly. FIG. 6 is a diagram for explaining this. When the serial transmission type pulse data shown in FIG. 6 (a) is transmitted at the transmission timing shown in FIG. 6 (b), the pulse data at the transmission timing is shown. Is transmitted as it is, different data will be transmitted as shown in FIG. 6 (c). This occurs because the minimum period T1 in which the pulse data changes is shorter than the transmission period T2.

To solve this problem, a circuit described in Japanese Utility Model Laid-Open No. 57-141450 has been proposed. This employs a method in which the rising and falling edges of pulse data are stored and sent in synchronization with the transmission timing. According to this technique, when the rising edge and the falling edge of the pulse data do not coincide with the transmission timing, the pulse data is not transmitted until the transmission timing is reached, and the pulse width (time) of the transmitted pulse data becomes longer and is transmitted as the original pulse data. There will be a time difference with the pulse data. That is, pulse data cannot be transmitted in real time. Further, as the transmission time becomes longer, the number of data to be temporarily stored increases, and a large storage capacity is required to store the rising and falling of the pulse data, which is not economically preferable.

[Problems to be Solved by the Invention] Therefore, the present invention can transmit and display pulse data accurately and without a time delay, even though the transmission period is longer than the minimum period in which pulse data changes. The purpose is to realize a data transmission display.

[Means for Solving the Problems] The present invention uses the following means in order to solve the above problems.

A means for detecting pulse data that changes with time in a cycle shorter than the minimum change cycle and monitoring the occurrence of the change; a pulse for the pulse in the transmission cycle longer than the minimum change cycle. Means for discriminating whether or not a change in data is detected, Means for outputting the detected pulse data and the discrimination result by the discrimination means for each of the transmission cycles, and Output data by the output means Display means for inputting and displaying based on the input data.

[Operation] When each of the above means is used, whether or not there is a change in the pulse data is monitored in a short cycle, and it is further determined whether or not a data change has occurred within the transmission cycle. Change of times (high → low → high or low →
High-to-low) occurs, and it is possible to detect and transmit a pulse with a short time width that is overlooked by simply detecting the level of pulse data for each transmission cycle, and it is displayed. That is, the pulses P1, P2, P3, etc. having a short period shown in FIG. 6 (a) are transmitted and displayed without being overlooked. Moreover, there is no time delay in the transmitted data.

[Advantage of Invention] Therefore, although the data is transmitted in a cycle longer than the cycle in which the serial-format pulse data changes,
Accurate data can be transmitted and displayed in real time, and accurate data can be transmitted to a person who monitors the transmitted data.

[Embodiment] FIG. 1 is a block diagram showing an example in which the pulse data transmission indicator of the present invention is used for diagnosis of an electronic control unit mounted on a vehicle.

Data from various sensors 4a, 4b and the like are input to the electronic control unit 2 and used for control. The input data is stored in the RAM in the electronic control unit 2 and processed based on the program stored in the ROM, and the drive signal is output to the various actuators 6a, 6b etc. based on the processing result. . To diagnose the electronic control unit 2, a diagnostic tester 10 is connected to the electronic control unit 2 via the diagnosis connector 8. In order to diagnose the electronic control unit 2 using the diagnostic tester 10, it is necessary to transmit the pulse data in the electronic control unit 2 to the diagnostic tester 10.
In the case of the present embodiment, the data transmission cycle is longer than the pulse data change cycle in the electronic control unit 2. Diagnostic tester 10 to receive accurate pulse data under this condition
Is programmed to do the following:

FIG. 2 shows a process executed by the diagnostic tester 10 in an interrupted manner at a predetermined cycle. The execution cycle is shorter than the minimum change cycle T1 of the pulse data in the electronic control unit 2 illustrated in FIG. 5 (a).

In step S2, it is determined whether the pulse voltage detected at that time is high level or low level. If it is high level, step S4 is executed and it is judged whether or not the previously detected pulse voltage was also high level. If NO here, that is, if the pulse data has changed within this period, 1 is added to the counter in step S6. Here, this counter is zero-cleared in step S26 described later. Since this step S26 is executed immediately after the output or transmission of the data shown in step S24, the counter counts the number of changes of the pulse data after the pulse data transmission.

If it is determined in step S2 that the pulse voltage detected this time is at a low level, it is determined in step S8 whether or not the data has changed between the previous detection and the current detection, and if it has changed, The counter is incremented by 1 in step S10. That is, the number of counts is increased each time the data changes from the high level to the low level or vice versa in steps S6 and S10.

After the above processing is executed, steps S12 to S14 are executed and the current detection value is substituted as the previous pulse voltage detection value for the next processing.

In the above processing, steps S4 to S8 are repeatedly executed at a cycle shorter than the minimum pulse data change cycle T1 to monitor the occurrence of pulse data change.
Also, after the counter is cleared to zero in step S26,
Whether steps S6 to S10 are executed and the counter is added, or steps S6 to S10 are skipped and not added, it is determined whether or not a data change has occurred within the transmission cycle. If the data has not changed, the count value is zero, and if the data has changed, the count value is 1 or more. In the present embodiment, it is programmed to count not only the occurrence or non-occurrence but also the number of changes.

The process shown in FIG. 3 is a process executed at each data transmission timing, and this cycle is the execution cycle of the process shown in FIG. 2 or the minimum of the pulse data shown in T1 of FIG. 5 (a). It is longer than the change cycle, and is executed at the timing shown in FIG. 5 (b), for example.

In step S20, the pulse voltage at the time of execution is read, and then in S22, the count value at that time is read. Next, the process proceeds to step S24, and the data read in step S20 and step S22 is output or transmitted. The count value transmitted here indicates the result of determining whether or not the pulse data has changed. That is, if it is zero, there is no change, and if it is 1 or more, there is a change. Each data is sent in a serial transmission format. The counter after data transmission is cleared to zero in step S26.

The above processing is executed by controlling the CPU in the electronic control unit 2 based on the instruction code sent from the diagnostic tester 10.

The data thus transmitted to the diagnostic tester 10 is input or received and displayed by the processing of FIG.

In step S30, it is determined whether the input pulse voltage is high level or low level. If it is high level, step S32 is executed and a point is plotted on the display of the diagnostic tester 10 at a position indicating high level. Here, the horizontal position on the display corresponds to the transmission timing,
Each time the processing shown in the figure is repeated, the display is shifted rightward by a unit length. When the low level signal is received, points are blotted at the position indicating the low level in step S34. Next, step S36 is executed, and a horizontal line having a unit length is displayed from the plot position. This state is shown in FIG. 5 (d). Then, the process proceeds to step S38, and the number of changes in the transmission cycle is compared with the predetermined value "1". If the count value is 1 or more, it corresponds to the change of the pulse data within the transmission cycle. In that case, the step
Display a vertical line connecting the high level and the low level as shown in S40. As a result, a display corresponding to the change is made.

FIG. 5 (f) shows the vertical line displayed in step S40, and FIG. 5 (g) shows the display after execution of step S40. That is, in FIG. 5 (g), the display of (f) is superimposed on the display of (d). As shown in FIG. 5 (g), it can be understood that the transmitted and displayed data closely approximates the original pulse data shown in FIG. 5 (a), and there is no time delay.

In addition, when FIG. 5 is examined in detail, it is understood that the vertical line in the portion corresponding to the count value of 1 shown in the (e) column indicates the data change that occurred once before the transmission cycle. To be done. It is understood that the vertical line in the portion corresponding to the count value 2 represents the data change that has occurred twice in the transmission cycle prior to that, as one vertical line. When displaying two data changes with one vertical line, one of the vertical lines is not connected and it is easy to intuitively understand that there was one round-trip (two times) data change. it can. The count value 3
It is recognized that the portion corresponding to is displayed in the same manner as when there was only one change, although there were actually three data changes. That is, it is understood that when the count value is 3 or more, the change in the pulse data is omitted on the display.

Therefore, it is understood that the present transmission display method can transmit and display data without error if the transmission period of the data is less than 3 times the minimum change period of the pulse data.

In the present embodiment, the number of changes in the transmission cycle is counted, and it is determined whether it is zero or more than 1, and the vertical line in FIG. 5 (f) is displayed by this. It is also possible to use a flag. That is, the same display can be obtained even if the flag is set to be set instead of being added in steps S6 and S10 and the flag is set to be reset in step S38. In this case, step S26 is changed to reset the flag.

[Brief description of drawings]

FIG. 1 is a system diagram when the transmission indicator of the present invention is applied to a diagnostic device for an electronic control unit for an automobile, and FIG. 2 is a graph showing changes in pulse data by monitoring changes in pulse data. FIG. 3 is a diagram showing a processing procedure for determining whether or not it is, FIG. 3 is a diagram showing a processing procedure for data transmission, FIG. 4 is a diagram showing a processing procedure for receiving and displaying data, and FIG. Of the timing chart and display results of No. 6,
The figure is a diagram showing a display result when transmitted by the conventional method. 2 ... Electronic control device 10 ... Diagnostic tester S4, S8 ... Pulse data change monitoring processing step S6, S10, S26, S38 ... Pulse data change determination processing step S24 ... Data transmission processing step S32, S34, S40 ... Data display processing Step

Claims (1)

[Scope of utility model registration request] 1. A means for detecting time-varying pulse data at a cycle shorter than its minimum change cycle to monitor the occurrence of the change, and the monitoring means within a transmission cycle longer than the minimum change cycle. Means for determining whether or not a change in the pulse data is detected, means for outputting the detected pulse data for each transmission cycle, and a determination result by the determining means, and output data by the output means And a display means for displaying based on the input data.