JP3075489B2 - Analog data transmission device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a distributed control system in which a man-machine interface and a process controller are combined, in which numerical data is transmitted from the man-machine interface to the process controller while continuously increasing and decreasing. The present invention relates to an analog data transmission device used for the device.

[0002]

2. Description of the Related Art Conventionally, when control data is exchanged between a man-machine interface and a process controller via a data way, an input value is continuously increased from the man-machine interface to the process controller while pressing a key. Or, numerical data may be transmitted while decreasing. In this case, in the man-machine interface, the input value is increased / decreased in proportion to the key pressing time on the display device, and the displayed input value is converted into a numerical code at regular intervals as transmission data,
Send to the process controller via the data way. The process controller that has received the transmission data stores the numerical value therein, and sends the reply data containing the numerical data to the man-machine interface again as a response to the reception of the transmission data.

[0003] Upon receiving the return data, the man-machine interface takes in the numerical value therein and displays it as a display data value while comparing it with the input value. That is, in the man-machine interface, the numerical value input inside the process controller is displayed as the return data value.
The user can input a numerical value while constantly checking the value. By the way, in the case of a system in which the transmission speed of the data way is particularly low, the time from when the numerical value is increased / decreased by the key operation to when the transmission data is transmitted and the response data is further received becomes longer. Therefore, the response data value follows the input value displayed on the man-machine interface significantly behind. Therefore, in such a case, when the transmission data is sent, the display data value is changed to follow the transmission data as expected without waiting for the return data to arrive.

[0004]

However, in such a system in which the transmission speed of the data way is particularly slow, a numerical value displayed as a return data value regardless of the timing at which the transmission data is actually input to the process controller. If the key press operation is stopped while watching the display, the difference between the numerical value finally input into the process controller and the final value There is an inconvenience that the operation becomes confused when it becomes large. The present invention has been made in order to solve the above-mentioned problems, and an object of the present invention is to provide a system in which the transmission speed of a data way is particularly low, in which a key-input numerical value and a numerical value input into a process controller are input. It is an object of the present invention to provide an analog data transmission device capable of reducing a difference from a numerical value, eliminating confusion in input operation, and continuously inputting a numerical value while increasing / decreasing a numerical value with confidence.

[0005]

In order to achieve the above object, the present invention provides an input key comprising an up key and a down key, wherein the input value is increased or decreased in an analog manner by keeping the key pressed. Means for transmitting a numerical value obtained by increasing or decreasing the numerical value of the previous transmission data to the communication line at regular intervals as transmission data in accordance with an instruction to increase or decrease the numerical value input from the key; Means for displaying a numerical value on a display unit, and, in response to the transmitted data, when the reply data indicating that the numerical data has been received and the content of the received numerical value is transmitted from the transmission destination via the communication line, the reply data is displayed. In the analog data transmission device equipped with means for displaying the numerical value included in the display on the display device, set the period for converting the input numerical value into transmission data and transmitting it to the communication line Means for setting an increase / decrease value between a numerical value transmitted as transmission data and a numerical value to be transmitted next time, and a maximum value of a difference between the newly transmitted transmission data and the numerical value included in the reply data. Checks the means for setting the allowable value and whether or not the input key is pressed at every preset cycle, and if the up key is pressed, adds the value of the increase / decrease range to the previously transmitted numerical value Means to create transmission data, and if the down key is pressed, means to create transmission data by subtracting the value of increase / decrease from the previously transmitted value, and the numerical value and reply data in the created transmission data Means for calculating a difference from the numerical value in the table and transmitting the transmission data to the communication line when the difference is within the maximum allowable value.

[0006]

According to the present invention, a cycle for converting an input numerical value into transmission data and transmitting it to a communication line, a value of an increase / decrease value between a numerical value transmitted as transmission data and a numerical value transmitted next time as transmission data, The maximum allowable difference between the transmission data to be transmitted and the numerical value included in the reply data is set in advance. As a result, at each set cycle, it is checked whether the input key is pressed or not, and if the up key is pressed, the value of the increase / decrease range is added to the previously transmitted value to create the transmission data When the down key is pressed, transmission data is created by subtracting the value of the increase / decrease range from the previously transmitted numerical value. Further, the difference between the numerical value in the created transmission data and the numerical value in the reply data is calculated,
When the obtained difference is within the allowable maximum value, the transmission data is transmitted to the communication line.

[0007]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is a block diagram showing a configuration of a distributed control system combining a man-machine interface and a process controller to which the present invention is applied. In FIG. 1, reference numeral 1 denotes a man-machine interface, which is connected to process controllers 3 and 4, which are destinations of data, via a data way 2 which is a communication line. The figure shows that transmission data and return data are exchanged between the man-machine interface 1 and the process controller 3. The man-machine interface 1 includes a display such as a CRT (not shown) and a keyboard serving as an input key.

FIG. 2 shows a constant table formed in a memory built in the man-machine interface 1. An address m is a maximum allowable value of a difference between newly transmitted transmission data and a numerical value included in return data. A constant area for storing a certain limiter LT is secured, and a constant area for storing a value n of an increase / decrease range between a numerical value transmitted as transmission data and a numerical value transmitted as transmission data next time is allocated at an address m + 1, and an address m + 2 is stored at an address m + 2. Is provided with a constant area for storing a cycle t for converting an input numerical value into transmission data and transmitting the data to a communication line. In the constant table, when a system is constructed or a system configuration is changed, set values which are considered optimal for the system are stored in advance. If the value set in the constant table in advance becomes inappropriate, it can be changed as appropriate.

FIG. 3 shows an up key 5 and a down key 6 provided on a part of the keyboard of the man-machine interface 1. By depressing any of these keys 5 and 6, the numerical value input to the man-machine interface 1 can be continuously increased or decreased, and the input numerical value is displayed as a pattern expansion / contraction display on the display. By displaying, it is possible to increase or decrease the input numerical value with an analog feeling.

FIG. 4 is a time chart showing changes in numerical values exchanged between the man-machine interface 1 and the process controller 3 via the data way 2. In the man-machine interface 1, when the up key 5 is kept depressed, transmission data transmission processing is performed in accordance with a clock pulse having a cycle t stored in advance in the constant table of FIG. It rises by n%. Following the change in the numerical value of the transmission data, the value of the display data also increases in n% units with a delay time. The value of the display data indicates a change in a numerical value sent as return data from the process controller 3 that has received the transmission data.

When the process controller 3 receives the transmission data, the process controller 3 updates the internally stored numerical value based on the received data, and then returns the updated numerical value as reply data.
That is, the same numerical value as the transmission data is used as the reply data,
Send to man-machine interface 1. Therefore, in the man-machine interface 1, a delay time corresponding to the sum of the processing time of the process controller 3 and the transmission time of the data way 2 occurs after sending the transmission data and receiving the reply data.

The delay time is determined by the process controller 3
In addition, the timing of the change of the transmission data value does not always correspond to that of the display data value as shown in FIG. However, the difference between the transmission data value and the display data value does not exceed the value of the preset limiter LT. In the figure, the maximum difference is 2n%, which is a value not exceeding the limiter LT. As a result, in the figure, transmission processing of transmission data is performed at the rising timing of each clock pulse.

FIG. 5 is a diagram showing a display example of the display.
The figure shows a change in which the transmission data value and the display data value (reply data value) increase when the up key 5 is kept depressed. The transmission data value always increases first, and thereafter the display data value increases. The value follows. Further, the difference between the transmission data value and the display data value does not always exceed the limiter LT. That is, even if the transmission data value increases while the state where the up key 5 is kept depressed, the follow-up of the increase in the display data value is delayed due to the state of the process controller 3 and the data way 2, and the difference exceeds the limiter LT. After that, transmission processing of transmission data is not performed. After that, the return data is sent from the process controller 3 and the display data value increases, and when the difference becomes within the limiter LT, the transmission data transmission process is restarted.

FIG. 6 is a flowchart systematically showing the above processing. In the figure, first, a time t is waited (S1), and when the time is up, transmission data is created as a transmission data value by adding n% to the previously transmitted transmission data value (S2). Next, the numerical value of the currently received reply data is subtracted from the numerical value of the created transmission data, and it is determined whether or not the difference is equal to or smaller than the limiter LT (S3).

If the value is equal to or less than the limiter LT (S3Ye
s) A transmission process for transmitting the created transmission data to the process controller 3 is performed (S4). When the transmission processing of the transmission data is completed and when the transmission data is not equal to or less than the limiter LT (S3 No), the latest transmission data value transmitted so far and the latest response data value received are displayed on the display (S5). ). Next, it is determined whether or not the up key 5 is continuously being pressed, and if it is being pressed (S6Y
es), return to the beginning and continue the processing. If the button is not being pressed (S6 No), the process ends.

By performing such processing, in the embodiment, when the input value is increased in an analog manner by continuously pressing the up key 5, only the transmission data value is increased far apart from the display data value. Disappears, and the display always displays the value input to the process controller 3, so that even if the operator performs a key operation by focusing only on the transmission data value of the display,
The value actually input to the process controller 3 and the value input by the key operation are not extremely separated. That is, the inconsistency of the input numerical values between the man-machine interface 1 and the process controller 3 is resolved, and confusion in operation is eliminated.

When the down key 6 is pressed, a process for continuously reducing the transmission data value is performed. Also, as a special process, when it is desired to set the analog operation from the man-machine interface 1 to change from 0% to 100% at once in an emergency, both the value n of the increase / decrease width and the value of the limiter LT are required. 10
This can be realized by setting it to 0%.

[0018]

As described above, according to the present invention, when the up key or the down key is depressed, the value of the previously increased / decreased width is added to or subtracted from the previously transmitted value and transmitted. Creates data, calculates the difference between the numerical value in the transmission data and the numerical value in the reply data, and sends the transmission data to the communication line if the obtained difference is within a preset allowable maximum value. With such a configuration, the following effects can be obtained.

(1) The increment or decrement of the numerical value sequentially transmitted to the communication line as the transmission data becomes constant, and the change of the numerical value to be transmitted can be made substantially continuous. (2) Even if the processing time of the communication line and the transmission destination is slow, a numerical value that is farther than the numerical value indicated in the reply data from the transmission destination is not transmitted as transmission data, and the displayed key operation is input. The difference between the value and the value captured at the destination is reduced, thereby eliminating operational confusion. (3) The set value of the data transmission process can be arbitrarily set in advance in accordance with the application, the processing time of the communication line, and the like, so that the usability of the user is improved.

[Brief description of the drawings]

FIG. 1 is a block diagram showing a configuration of a distributed control system to which the present invention is applied.

FIG. 2 is a diagram showing a constant table formed in a memory.

FIG. 3 is a diagram showing an up key and a down key provided on a keyboard.

FIG. 4 is a time chart showing changes in data values.

FIG. 5 is a diagram showing an example of a change in a data value displayed on a display.

FIG. 6 is a flowchart showing a part of the operation of the embodiment.

[Explanation of symbols]

 1 Man-machine interface 2 Data way 3, 4 Process controller 5 Up key 6 Down key

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int.Cl. ⁷ , DB name) G06F 3/02 360-390 G06F 3/023 G05B 15/02

Claims (1)

(57) [Claims] An input key consisting of an up key and a down key for continuously increasing / decreasing an input numerical value by continuously depressing the key, and an instruction for increasing / decreasing a numerical value input from the input key in response to an instruction to increase / decrease the value of the previous transmission data. Means for transmitting a numerical value obtained by increasing or decreasing the numerical value as transmission data to a communication line at regular intervals, means for displaying a numerical value in the transmitted transmission data on a display, Means for displaying, on a display, a numerical value included in the reply data when reply data indicating that the numerical data has been received and content of the received numerical value are transmitted from the transmission destination via a communication line. Means for setting a period for converting an input numerical value into transmission data and transmitting it to a communication line, and a method for transmitting the numerical value transmitted as transmission data and A means for setting a value of an increase / decrease range with respect to a numerical value to be transmitted as transmission data; a means for setting a maximum allowable value of a difference between a newly transmitted transmission data and a numerical value included in reply data; Each time, check whether the input key is pressed or not, and if the up key is pressed, add the value of the increase / decrease range to the previously transmitted value to create the transmission data, and press the down key If so, means to create transmission data by subtracting the value of the increase or decrease from the previously transmitted value, and calculate the difference between the value in the created transmission data and the value in the reply data, and calculate the difference. Means for transmitting transmission data to a communication line when the transmission data is within the maximum allowable value.