JPH09184856A - Digital display measuring instrument - Google Patents

Abstract

PROBLEM TO BE SOLVED: To make it possible to use a digital panel for multiple applications by providing multiplexer for switching between a code signal from a coding circuit and coded message data from a data input buffer. SOLUTION: A data input buffer 14 receives coded message data coded from characters and numeric characters which can be displayed on a display unit 11 supplied from the exterior. A multiplexer 15 switches data supplied to a character display circuit 16 between a code signal output from a coding circuit and a coded message data output from the buffer 14. The multiplexer 14 is switched by a switching signal supplied from the exterior. Thus, the unit 11 can display the simple message from the exterior in addition to the digital display of the conventional measured value with the simple constitution of only adding the buffer 14 and the multiplexer 15 to the conventional digital panel meter.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a digital display measuring device for digitally displaying an analog electric signal,
In particular, the present invention relates to a digital display measuring device generally called a digital panel meter having the simplest structure as such a display device.

[0002]

2. Description of the Related Art When measuring a physical quantity to be measured, it is common to convert the physical quantity into an electric signal and then measure and display the strength of the electric signal with an electric measuring instrument. There are an analog measuring instrument which performs an analog display for displaying a quantity and the like, and a digital display measuring device such as a digital panel meter which converts a measured value into a digital value and displays it in decimal. In recent years, digital panel meters are often used. The present invention is also applicable to a digital display measuring device such as a digital panel meter.

FIG. 3 is a diagram showing the structure of a digital panel meter and an example of its use. As shown in (1) of FIG. 3, the digital panel meter 10 has a strength (usually a voltage value) of an analog electric signal output from the measurement target 100.
Is displayed as a digital value. After the analog electric signal is amplified by the preamplifier 18, it is converted into a digital signal by the analog / digital (A / D) converter 12 and further displayed by the encoding circuit 13 in decimal. The code is changed, and the character display circuit 16 drives the display 11 so that the measured value is displayed in decimal according to the code signal. The display unit 11 has a display unit for displaying a one-digit number in seven segments for the number of display digits, and each segment is LE
D, a fluorescent display tube, a liquid crystal or the like is used. There are several methods by which the character display circuit 16 drives the display device 11, but a static drive method and a multiplex drive method are common. Although the numbers are displayed, some display a simple alphabet such as "over" in association with the display of the measured value.

FIG. 3 (2) is a diagram showing a configuration of a control system for controlling the controlled object 101, in which a plurality of measured values are displayed on the digital panel meter. Reference numeral 102 indicates a control unit, which is usually composed of a computer. In order to detect the state of the controlled object 101, the control unit 102 receives a detection signal output from a sensor provided in the controlled object 101, generates a control signal based on the detection signal, and sends the control signal to the controlled object 101. Here, it may be required to display a physical quantity (current, voltage, power, temperature, etc.) indicating the state of the controlled object 101. In such a case, a sensor or an output circuit that generates an electric signal indicating such a physical quantity is provided in the controlled object 101, and the output signal is supplied to the digital panel meters 10A-10N and displayed.
Since such a physical quantity is often required by the control unit 102, it is also sent to the control unit 102. The signal sent from the digital panel meters 10A-10N to the control unit 102 may be both the analog signal amplified by the preamplifier 18 and the converted digital signal.

In the system as shown in (2) of FIG. 3, it is often necessary to display a numerical value such as a calculated value or a message to the operator according to the processing of the control unit 102. Since the control unit 102 is usually a computer and has a display and the like, it is general to perform the necessary display for these. However, the position where the display is required is the control unit 10.
2 is separated from the display device 103a, 10
3b etc. were provided and it displayed. There are various types of display devices that can display numbers and characters by a fixed number of digits and can display graphics.

[0006]

In the system as shown in FIG. 3 (2), when a display is required, it is necessary to provide a separate display device even when performing simple display of numbers and alphabets. . However, if a separate display device is provided, the cost increases and there is a problem that it is necessary to secure a space therefor.

The present invention has been made in order to solve such a problem, and paying attention to the fact that a display of a digital panel meter can also perform a simple display, a display that can arbitrarily display the digital panel meter. The purpose of the device is to enable more versatile use.

[0008]

In order to achieve the above object, the digital display / measuring device of the present invention supplies data to be supplied to a character display circuit from the outside in a form suitable for character display of the digital display / measuring device. A multiplexer is provided to allow selection between coded message data and coded data representing measurement results.

That is, the digital display measuring device of the present invention comprises a display unit having a plurality of display units of 7 segments,
An analog / digital converter that converts an input analog electrical signal into a digital signal, a coding circuit that converts the output value of the analog / digital converter into a code signal for displaying on a display, and a code signal on the display In a digital display measuring device provided with a character display circuit for controlling so that a display corresponding to the above is performed and a timing control circuit for controlling the operation timing of each part, encoding of characters and numbers that can be displayed on a display device is coded. A data input buffer to which message data is externally supplied, and a multiplexer for switching the data to be supplied to the character display circuit between a code signal output from the coding circuit and coded message data output from the data input buffer. It is characterized by being provided.

In the digital display measuring device of the present invention, it is possible to display a simple message from the outside in addition to the conventional digital display of the measured value by simply adding a simple circuit. The message data supplied from the outside needs to be data showing a simple message that can be displayed on the display, and its format must be such that it can be supplied to the character display circuit as it is and displayed. .

[0011]

1 is a diagram showing the configuration of a digital display measuring apparatus according to an embodiment of the present invention. In FIG. 1, reference numeral 11 is a display having a plurality of 7-segment display units, 17 is a preamplifier for amplifying an input analog electric signal, and 12 is an analog / digital conversion for converting the output of the preamplifier 18 into a digital signal. A vessel
Reference numeral 13 is a coding circuit for converting the output value of the analog / digital converter 12 into a code signal for decimal display on the display 11, and 16 is controlled so that the display corresponding to the code signal is displayed on the display 11. 17 is a character display circuit, 17 is a timing control circuit for controlling the operation timing of each part, and 14 is a data input buffer for receiving coded message data in which characters and numbers which can be displayed on the display 11 are coded. 15 is the data to be supplied to the character display circuit 16,
3 and the code signal output from the data input buffer 14
3 shows a multiplexer for switching between coded message data output from the. The switching in the multiplexer 15 is performed by a switching signal supplied from the outside.

As is clear from comparison with (1) in FIG.
The digital display measuring device according to the present embodiment has a configuration in which a data input buffer 14 and a multiplexer 15 are provided in a conventional digital panel meter. With a simple configuration in which such a part is added, it becomes possible to display a simple message from the outside in addition to the conventional digital display of measured values.

Message data supplied from the outside is
It is necessary that the data is a data indicating a simple message that can be displayed on the display unit 11, and that the format is such that it can be directly supplied to the character display circuit 16 for display. If it is not supplied in such a format, it is necessary to separately provide a coding circuit, which causes a problem of cost increase.

FIG. 2 is a diagram showing a display example of message data in this embodiment. Since the display unit is only provided with a plurality of display units of 7 segments and complicated display cannot be performed, since it is such a simple display, the message data is displayed in a coded format that can be displayed as it is from the outside. It is possible.

[0015]

According to the present invention, a message can be displayed though it is simple by adding a simple circuit to the existing digital panel meter. As a result, if it is a simple message, without providing a separate display,
Since the necessary display can be performed, the system can be configured at low cost.

[Brief description of the drawings]

FIG. 1 is a diagram showing a configuration of a digital display measuring device according to an embodiment of the present invention.

FIG. 2 is a diagram showing a display example of a message in the embodiment.

FIG. 3 is a diagram showing a conventional example of a digital panel meter and a configuration example of a system using the same.

[Explanation of symbols]

 11 ... Display device 12 ... Analog / digital converter 13 ... Encoding circuit 14 ... Data input buffer 15 ... Multiplexer 16 ... Character display circuit 17 ... Timing control circuit 18 ... Preamplifier

Claims (1)

[Claims] 1. A display (11) having a plurality of display units of 7 segments, an analog / digital converter (12) for converting an input analog electric signal into a digital signal, and the analog / digital converter (12). And an encoding circuit (13) for converting the output value of (1) into a code signal for display on the display (11), and controlling so that the display corresponding to the code signal is performed on the display (11). Character display circuit (16)
And a timing control circuit (17) for controlling the operation timing of each part, wherein a coded message data obtained by coding characters and numbers which can be displayed on the display (11) is supplied from the outside. Data input buffer (14) and data to be supplied to the character display circuit (16),
Digital display measurement comprising a multiplexer (15) for switching between the code signal output from the encoding circuit (13) and the coded message data output from the data input buffer (14). apparatus.