JP2000347626A - Display device and method for preventing erroneous display - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a display device and method for preventing erroneous display capable of always preventing erroneous display. SOLUTION: A route indicator provided with a display part having many of LEDs checks all of the LEDs of the display part at time of starting and idling and stores an address of a troubled LED. In a step S11, the address of the LED to be used in a display pattern (to be light up) is checked at a time of display. In a step S12, whether the addresses checked in S12 includes the address of the troubled LED. When the address of the troubled LED is included, the process proceeds to a step S13. In the S13, it is determined whether the number of the addresses of the troubled LEDs or the number of troubled LEDs reaches the number that may cause garbage characters. When it is determined that the number reaches that number, an LED power is turned off in a step S14 and indication of trouble is provided to external. When the address of the troubled LED is not included in S12 or when the number of the troubled LEDs does not reach that number, display is provided.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a display device for displaying required codes (including characters and symbols) by a plurality of display elements, and more particularly to a display device suitable for a course display.

[0002]

2. Description of the Related Art Conventionally, a route indicator has a large number of LEDs.
(Light Emitting Diode)
Symbols such as 1, 2, etc. are displayed in a dot pattern. The display data supplied to the display unit having a large number of LEDs is collated and checked by the redundantly configured CPU.

[0003]

However, the lighting of each LED of the display unit is not checked, and whether the required code is displayed correctly depends on a visual check and is always checked. Can not
There was a risk of incorrect display.

[0004] The present invention has been made under such circumstances, and has as its object to provide a display device and an erroneous display prevention method capable of always preventing erroneous display.

[0005]

In order to achieve the above object, according to the present invention, a display device is configured as described in the following (1) to (8), and an erroneous display prevention method is described as the following (9). To be configured.

(1) a display section having a plurality of display elements;
A first failure display element detecting means for detecting a failed display element from among the plurality of display elements; and a display element necessary for displaying the pattern when the display section displays a required pattern. From among them, a second failure display element detection means for detecting a failure display element detected by the first failure display element detection means, and a failure display element detected by the second failure display element detection means. A display device comprising: an erroneous display determination unit that determines whether a required pattern is erroneously displayed; and a display stop unit that stops display by the display unit when the erroneous display determination unit determines that the display is erroneous.

(2) The display device according to (1), wherein the first failure display element detection means performs failure detection for a plurality of display elements arranged in close proximity.

(3) In the display device according to the above (1) or (2), the first failure display element detecting means detects a failure based on an abnormality in a current value flowing in each display element or each display element unit. Display device.

(4) In the display device according to any one of the above (1) to (3), the erroneous display judging means includes the number of fault display elements detected by the second fault display element detecting means, or A display device which determines that an erroneous display is made when the number of fault display element units exceeds a predetermined number.

(5) In the display device according to any one of the above (1) to (3), the erroneous display judging means includes the number of fault display elements detected by the second fault display element detecting means, or A display device which determines that an erroneous display is made when the number of fault display element units exceeds a predetermined number for each display pattern.

(6) The display device according to any one of (1) to (5), wherein the display element is an LED.

(7) In the display device according to any one of the above (1) to (5), the display stop means stops the display by shutting off a power supply of the display unit, and further stops the display. A display device provided with means for displaying a failure state to the outside when a failure occurs.

(8) A display device according to any one of (1) to (7), wherein the display device is a route indicator.

(9) A method for preventing an erroneous display of a display device provided with a display unit having a plurality of display elements, wherein a step A of detecting a failed display element from among the plurality of display elements of the display unit; When a required pattern is displayed on the display unit, a step B for detecting the fault display element detected in step A from among the display elements necessary for displaying the pattern, and a step B for detecting the fault display element detected in step A. A step C for determining whether or not the required pattern is erroneously displayed due to the presence of the fault display element, and a step D for stopping the display by the display unit when it is determined in step C that the erroneous display is performed. Display prevention method.

[0015]

The embodiments of the present invention will be described in detail below with reference to examples of a course indicator. The present invention is not limited to the form of a device such as a route indicator, but can be similarly implemented in the form of an erroneous display prevention method.

[0016]

FIG. 1 is a block diagram showing the configuration of a "route indicator" according to an embodiment. As shown in the drawing, the apparatus of this embodiment includes a control unit 100 and an LED display 200. As shown in FIG. 2, the LED display section 12 of the LED display 200 has two display units of 256 dots (256 LEDs) for displaying each code in a dot pattern. For each dot, that is, for each LED, the left end of the uppermost row of the left unit is numbered 1 (n = 1), and the same row is numbered 2 and 3 to the right, the right end is numbered 16 and the left end of the next row is number 17 ......, the right end of the bottom line of the unit is 25
No. 6 and the number (address) in the order of the arrangement of the LEDs are given. Similarly, for the right side unit, the left end of the top row is 2
The right end of the bottom row is numbered 512 and the LEDs are arranged in the order of arrangement. Note that the LED address is not limited to the order of arrangement, and each L, such as a row, a combination of row numbers, etc.
A code or the like corresponding to the ED on a one-to-one basis can be used.

First, the check of the display data will be described with reference to FIG. The control unit 100 is configured by a dual system of an A-system CPU 2 and a B-system CPU 5 as shown in the figure.

For example, 512 bits of a display pattern (dot pattern) for displaying the path opening direction are set to the A system CPU.
In response to the checking pulse from the CPU 2, the signals are input to the A-system CPU 2 and the B-system CPU 5 via the insulating buffer 1 and stored.

The 512 bits of display pattern data stored in the A-system CPU 2 are serially stored in the LED display 20.
0 is sequentially written to the shift register 9.

After the writing is completed, the data in the shift register 9 is latched by the latch 10 in accordance with the control signal from the A-system CPU 2.

The shift register 9 is shifted by a control signal from the A-system CPU 2, and the data in the shift register 9 is re-input to the A-system CPU 2 and the B-system CPU 5 via the buffer 6 and stored in each CPU as described above. The input data is compared with the input data.

The collation results of the A-system CPU 2 and the B-system CPU 5 are collated by the collation unit 3, and if one or both of the A-system CPU 2 and the B-system CPU 5 do not match the input data and the re-input data, a check is made. Relay C
The HR 4 is turned off, the power supply of the AC / DC conversion circuit 7 is cut off, and the display on the LED display 12 is stopped. A system CPU
In both the CPU 2 and the B-system CPU 5, if the input data matches the re-input data, the data 51 of the latch 10
LED display unit 1 via driver 11 with 2 bits
2 is driven, and the input display pattern is displayed.

Next, prevention of erroneous display due to LED failure will be described. First, the failure of each LED shown in FIG. 2 is detected by the flow shown in FIG. This operation is performed by both the A-system CPU 2 and the B-system CPU 5 at the time of starting the apparatus of the embodiment and at the time of idling without displaying. n = 0
The ED check flow starts. In s1, 1 is added to n to set n = 1, and the first LED is designated, and in S2, a dot check is performed. That is, in FIG. 1, the first LED ON (lighting) signal is latched by the latch 10, and the LED display unit 12 is driven by the driver 11. The current flowing through the first LED at this time is detected by the current sensor 8 and sent to the A-system CPU 2 and the B-system CPU 6. The current value sent in S3 is compared with a value in the normal range of the LED stored in each of the CPUs 2 and 5 in advance to determine whether or not there is a failure. If there is no failure in both the A-system CPU 2 and the B-system CPU 5, the process returns to S1, where n = 1 + 1 and the second LE
D is specified, and a dot check is performed in S2.

If one or both of the A-system CPU 2 and the B-system CPU 5 have a failure, the process proceeds to S4.
The number n, which is the address of the failed LED, is stored, and the process proceeds to S5. In S5, it is determined whether the 512th LED, which is the last LED, has been designated. If the 512th LED has not been checked, the process returns to S1, and the above operation is repeated. If n = 512 and the check of the 512th LED has been completed in S5, this flow ends.

The operation of determining garbled characters (erroneous display) will be described with reference to the flowchart shown in FIG. This operation is also performed by both the A-system CPU 2 and the B-system CPU 5. At S11, the address of the display pattern is checked. That is, in the number n of the LED to be used (turned on) in the display pattern, the dot check in FIG.
It is checked whether the LED number n stored in 2, 5 is included. If it is included in S12, it is determined that there is a failure, and the process proceeds to S13. If it is determined in S13 that the number of failed LEDs is equal to or larger than the number set in advance as a number that may cause garbled characters, the process proceeds to S14. If the failure LED number n is not included in S12, the process proceeds to S15. When the number does not reach the preset number in S13, the process also proceeds to S15.

The collating unit 3 determines the result of the determination by the A-system CPU 2 and
The judgment result of the B-system CPU 5 is collated. If the judgment result is S14 in one or both systems, the check relay 4 is turned off, the power supply of the AC / DC conversion circuit 7 is cut off, and the LED is turned off.
The power of the display unit 12 is turned off and the display is stopped. at the same time,
A fault is displayed outside the route indicator of the present embodiment. When the collation result in the collation unit 3 and the judgment result in both systems are S15, the display pattern is displayed.

As described above, according to this embodiment,
When a predetermined number of failed LEDs are included in the LEDs used for the display pattern, the display is stopped, and erroneous display can be prevented. Also, the LED is always checked,
False display is prevented. In addition, the display is not stopped only when a faulty LED is generated on the display unit, but is stopped only when a predetermined number of faulty LEDs are included in the LEDs used in the display pattern. Processing is performed to meet the needs of the site to reduce the size.

(Modification) In the above embodiment, the presence or absence of a failed LED is checked for each LED.
The present invention is not limited to this, and the present invention can be similarly implemented by checking a plurality of LEDs arranged in close proximity as a unit.

Further, in the embodiment, the determination of the possibility of garbled characters is uniformly determined by the number of failed LEDs used in the display pattern regardless of the type of display pattern. However, the present invention is not limited to this. Can be implemented by determining the number of failed LEDs when determining garbled characters in accordance with the above.

Further, although the embodiment uses an LED as a display element, the present invention is not limited to this, and the present invention can be implemented by using an appropriate display element such as an incandescent lamp or a discharge lamp.

In the embodiment, the control unit has a redundant configuration. However, the present invention is not limited to this, and the control unit can be implemented in a single processing form.

[0032]

As described above, according to the present invention,
The error display can be prevented at all times, and the processing is performed in accordance with the request of the site to reduce the number of device failures.

[Brief description of the drawings]

FIG. 1 is a block diagram showing a configuration of an embodiment.

FIG. 2 is an explanatory diagram of an LED display unit.

FIG. 3 is a flowchart illustrating an operation of a dot check.

FIG. 4 is a flowchart showing an operation of determining garbled characters;

[Explanation of symbols]

 2 A system CPU 3 Collation unit 4 Check relay 5 B system CPU 12 LED display unit

Claims (9)

[Claims] A display unit having a plurality of display elements; first failure display element detecting means for detecting a failed display element from the plurality of display elements; and a required pattern displayed by the display unit. In this case, a second fault display element detecting means for detecting a fault display element detected by the first fault display element detecting means from display elements necessary for displaying the pattern, An erroneous display determining means for determining whether the required pattern is erroneously displayed based on the presence of the fault display element detected by the fault display element detecting means; and A display device comprising a display canceling means for canceling the display of the display device. 2. The display device according to claim 1, wherein said first fault display element detecting means detects a fault in units of a plurality of display elements arranged close to each other. . 3. The display device according to claim 1, wherein the first failure display element detecting means detects a failure based on an abnormality in a current value flowing in each display element or each display element unit. A display device, comprising: 4. The display device according to claim 1, wherein the erroneous display determination unit is configured to detect the number of failure display elements detected by the second failure display element detection unit or to display a failure display. A display device for determining that an erroneous display is made when the number of element units exceeds a predetermined number. 5. The display device according to claim 1, wherein the erroneous display determination unit is configured to detect the number of failure display elements detected by the second failure display element detection unit or to display a failure display. A display device which determines that an erroneous display is performed when the number of element units exceeds a predetermined number for each display pattern. 6. The display device according to claim 1, wherein the display element is an LED. 7. The display device according to claim 1, wherein said display stop means stops the display by shutting off a power supply of said display unit. A display device comprising means for displaying a failure state to the outside. 8. A display device according to claim 1, wherein the display device is a route indicator. 9. A method for preventing an erroneous display of a display device including a display unit having a plurality of display elements, comprising: detecting a failed display element from among the plurality of display elements of the display unit; When a required pattern is displayed on the display unit, a step B for detecting the fault display element detected in step A from among the display elements necessary for displaying the pattern, and a fault detected in step B. A step C of determining whether the required pattern is erroneously displayed due to the presence of the display element, and a step D of stopping display by the display unit when it is determined in step C that the erroneous display is performed. Characteristic display error prevention method.