JP2971869B1 - Information display device and driving method thereof - Google Patents

Abstract

In a conventional information display device, a display unit has only a circuit that bypasses a shift register, so that it takes time to detect a faulty unit and the display speed is impaired. Was occurring. According to the present invention, a function of connecting display data in a shift register to a monitoring data bus for an arbitrary display unit, a function of disconnecting a clock signal for an arbitrary display unit, and a bypass of a similar shift register are provided. The information display device provided with the function and the function of turning off the display element array 2 simplifies the inspection process for confirming that no failure has occurred in the display unit 1 and the display procedure when a failure has occurred. Thus, the burden on the control unit 30 can be reduced, and simplification and speeding can be achieved, thereby solving the problem.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a series of display units in which display elements such as light-emitting diodes are arranged in a matrix, and a plurality of display units are connected in series. The present invention relates to an information display device that displays characters, figures, and the like.

[0002]

2. Description of the Related Art Conventional information display devices of this type include:
For example, there is one disclosed in JP-A-6-308906, the contents of which are shown in a block diagram of FIG.
The information display device includes a display unit 1 in which a plurality of display units 10 are connected in series, a control circuit 41 that sends display data D _{1 and the} like to each display unit 10, and a display unit 10 that is returned from the display units 10 connected in series. that excluding a monitoring circuit 42 which monitors the data D ₃ input from the monitoring data D ₂ and the control circuit 41, thereby matching the display data D ₁ and the monitoring data D ₂ and the monitoring data D _3, the failed display unit 10 The control unit 4 includes a CPU 43 for creating data.

FIG. 6 is a block diagram showing details of the configuration of the display unit 10. A display element array 101 in which display elements such as LEDs are arranged in a matrix, and a display element for controlling lighting of the display element array 101 are shown. Drive circuit 3
In addition, the display element driving circuit 3 includes
The two-way shift function of a 256-stage (16 × 16) configuration for taking in the display data D ₁ sent from the control circuit 41 via the signal line S-IN in synchronization with the clock signal from the signal line CLK shown in FIG. Is provided.

The display element driving circuit 3 has a latch circuit 32 for storing the display data D ₁ taken into the shift register 31 by a latch signal from a signal line LATCH.
A driver 33 for controlling the lighting of the display element array 101 in accordance with the latched display data D ₁ , analog switches 34 and 34 ′ for disconnecting the shift register 31 from the signal line S-IN, and an AND circuit 35, , An inverter 36 are provided.

Next, the operation of the information display device having the above configuration will be described. First, the display data D ₁ is transmitted from the control circuit 41 to the display unit 10 via the signal line S-IN and the analog switch 34. The data is transferred to the element driving circuit 3 twice. Therefore, the shift register 31 of the display element drive circuit 3 to display data D ₁ is sent, the ones returned to the monitoring circuit 42 display data D ₁ sent for the first time as monitoring data D _2.

Here, the monitoring circuit 42 converts the monitoring data D ₂ to C
The CPU 43 checks whether or not the display data D ₁ and the monitoring data D ₂ match. If it is determined that they match, the control circuit 41 sends a latch signal to the shift register 31. the display data D ₁ to the being captured by latching together to hold, to perform display by sending an enable signal.

When the CPU 43 determines that they do not match, it sends out an output for switching the switch SW (see FIG. 5), and the lowermost one of the display unit 10 and the monitoring circuit 42
In this state, the CPU 43 inverts the shift direction of the shift register 31 via the signal line SHIFT and outputs a clock signal. Then, the second display data D ₁ fetched by the shift register 31 becomes the monitoring circuit 42 from the reverse direction when the sending is performed as the monitoring data D _3.
Is taken in.

The CPU 43 detects the display unit 10 at the head of the mismatch between the monitoring data D ₃ output from the monitoring circuit 42 and the first display data D _1, and sends an individual signal to the display unit 10 to send an analog switch. 34
And the analog switch 34 'is closed to shift the shift register 31 of the failed display unit 10.
From the signal line S-IN.

Next, the CPU 43 creates display data excluding the failed display unit 10 and restores the switch SW to connect the display unit 10 excluding the failed display unit 10 to the control circuit 41, and the control circuit 41
Stores the display data created above in the display unit 10
Forward twice.

The first display data of the display data transferred twice is input to the monitoring circuit 42 as monitoring data.
Then, a comparison with the display data is performed for the second time, and thereafter, the same procedure as the above procedure is repeated, and the above procedure is repeated until a collation match between the two data is obtained.

[0011]

However, in the above-mentioned conventional information display device, the shift register 31 of the failed display unit 10 is bypassed. It is necessary to delete the portion corresponding to the failed display unit 10, causing a problem that the load on the control unit 4 increases.

[0012]

According to the present invention, as a specific means for solving the above-mentioned conventional problems, a display element array in which display elements are arranged in a matrix of digits and rows to perform lighting display is provided. A display driving circuit including a shift register for accumulating display data, a switch for connecting an output of the shift register to a monitoring data bus by a predetermined signal, and passing or bypassing the display data via the shift register by a predetermined signal A display unit provided with a switch for switching whether to pass, a switch for separating a clock signal to the shift register by a predetermined signal, and a switch for turning off the display element array by the display driving circuit by a predetermined signal. A plurality of display units connected in series, and display data sent to the display unit; An information display device, comprising: a control unit that checks monitoring data returned by a monitoring data bus with the display data and detects a defective display unit; and When a failure is detected, the display unit passes an instruction to pass display data to lower display units including the display unit in which the failure is detected, and disconnects the clock signal, and the control unit displays a higher display than the display unit in which the failure is detected. Output a signal to accumulate the display data corresponding to the shift register of the display unit higher than the display unit in which the failure is detected, and thereafter, display the lower display unit including the display unit in which the failure is detected. Releases the separation between the passage instruction and the clock signal, and sets the clock signal on the upper side of the display unit where the failure was detected. And driving the information display device in this state to output lower-order display data including the display unit in which the failure is detected from the control unit and accumulate the display data corresponding to the shift register. The problem is solved by providing a method.

[0013]

Next, the present invention will be described in detail based on an embodiment shown in the drawings. 1 is a display unit 1 of the information display device according to the present invention,
As shown in FIG. 2 described later, a plurality of display units 1 are connected in series, and are driven and controlled by various signals from the control unit 30.

The display unit 1 has a signal line D-IN.
A 256-stage shift register 5 for taking in the display data sent via the same in synchronization with the clock signal sent on the signal line CLK; a latch circuit 4 for storing the display signal taken in the shift register 5; A driver circuit 3 for controlling lighting of the display element array 2 based on the latched display data is provided similarly to the conventional example.

According to the present invention, the output of the shift register 5 is supplied to the display unit 1 by the monitoring data bus CHKDO.
, A switch 7 for disconnecting the upper display unit 1 from the monitoring data bus CHKDO, a flip-flop 8 for specifying the switches 6 and 7 by a signal on the signal line CHKEN, and a switch for the shift register 5. A switch 9 for separating the clock signal CLK, flip-flops 10 and 11 for designating and storing the designation of the switch 9 for each unit, and display data passing through the shift register 5 by a signal on a signal line PASEN. And a flip-flop 13 for designating and storing the switch 12.
4 and a signal line OFFE passing through flip-flops 15 and 16 to the other input while the lighting signal ENABLE is input to one input.
And an OR circuit 17 whose output is connected to the driver circuit 3 when a turn-off signal from N is input.

Next, the operation of the display unit 1 of the present invention having the above configuration will be described. In the description, it is assumed that an arbitrary plurality of the display units 1 are connected in series. First, when the display data in the shift register 5 of an arbitrary display unit 1 is taken out on the monitoring data bus CHKDO, the signal line CHKEN is set to "H" and the signal line SELCK is set to "L" → " A signal of "H" is input in the lower part of the display unit 1 from which display data is to be extracted, that is, the number of connection stages from the control unit 30.

In this way, the "H" signal set on the signal line CHKEN moves to the flip-flop 8 of the display unit 1 intended for reading, so that the switch 6 of the display unit 1 is closed. In addition, the output of the shift register 5 is connected to the monitor data bus CHKDO, and the switch 7 is opened to disconnect the monitor data bus CHKDO higher than the target display unit 1.

When disconnecting the shift register 5 of any display unit 1 from the clock signal CLK, a signal line
SELEN is set to “H”, and a signal that changes from “L” to “H” is input to the signal line SELCK in the same manner as described above by the number of connection stages from the lower level (control unit 30) of the display unit 1 from which display data is to be taken out. .

In this manner, the "H" signal set on the signal line SELEN moves to the flip-flop 10 of the display unit 1 for the purpose of disconnecting the clock signal CLK. By sending a signal that changes from “L” to “H”, the flip-flop 11 opens the switch 9 and holds this state.

Further, when the display data on the signal line D-IN is to bypass the shift register 5 of an arbitrary display unit 1, the signal line PASEN is set to "H", and the signal line SELCK is similarly set to "L". The signals from “→” to “H” are input by the number of connection stages from the lower level (control unit 30) of the display unit 1 for which a detour is desired.

In this way, the "H" signal set on the signal line PASEN is not applied to the display unit 1 intended for bypass.
In this state, a signal that changes from “L” to “H” is sent to the signal line SET in this state, whereby the flip-flop 14 switches the switch 12 to the detour side and holds this.

Similarly, when it is desired to turn off the display element array 2 of an arbitrary display unit 1, the signal line OFFEN is set to "H", and the signal line SELCK is turned off from "L" to "H". By inputting the number of connection stages of the display unit 1 and further transmitting a signal that changes from “L” to “H” to the signal line SET, the display element array 2 of the target display unit 1 is obtained.
Turns off.

By doing so, the information display device of the present invention can appropriately combine the above functions to change the contents of the shift register 5 of any display unit 1 to the signal line CHKDO.
, The control unit 30 can individually inspect the contents of the shift register 5 of each display unit 1, and can perform the shift of the failure without disconnecting the shift register 5 as in the conventional example. The register 5 can be specified.

At this time, in the information display device according to the present invention, since each of the shift registers 5 is individually inspected, if a plurality of shift registers 5 fail simultaneously, In addition, each fault location can be detected, thereby simplifying and speeding up the fault detection procedure.

FIGS. 2A and 2B show a method of driving the information display device after the failed display unit 1 is detected as described above. FIG. 2 shows a specific description for easy understanding. In the following description, it is assumed that eight display units 1 (A to H) are connected, and a failure is detected in the fifth display unit 1E from the bottom. The number is not limited.

In this case, as shown in FIG. 2A, the control unit 30 first instructs the display units 1A to 1E to separate the clock signal and to instruct the display unit 1A to bypass the shift register 5. As a result, only the upper three display units 1F to 1H have the clock signals valid, and the shift register 5
Are ready to input display data from the signal line D-IN. The control unit 30 controls the display units 1F to 1F.
The display data of H is output to the signal line D-IN.

Accordingly, the display data required by each of the shift registers 5 of the display units 1F to 1H is stored, and the control unit 30 subsequently proceeds to FIG.
As shown in (1), the separation of the clock signals from the display units 1A to 1E and the detour of the shift register 5 are released, and the clock signals of the display units 1F to 1H are separated.

Then, the control unit 30 controls the display unit 1
The display data of A to 1E is output to the signal line D-IN. At this time, the shift register 5 of each of the display units 1F to 1H in which the display data has been stored earlier has its clock signal disconnected, so that the display data stored therein does not shift. , Is held as it is.

With the above-described driving method, the shift register 5 of the failed display unit 1E becomes the highest order when the display data is output from the control unit 30 for the second time. Thus, there is no higher-order shift register 5 in which the display data is stored.

Therefore, the display data is not destroyed by passing through the failed shift register 5. If the display unit 1E is instructed to turn off the light by the means described above, the contents of the failed shift register 5 will not be displayed.

As is clear from the above description, according to the present invention, even when a display unit that has failed is generated, the control unit 3 can be used.
In the case of 0, it is not necessary to newly create display data in which the failed part is compressed, and it is possible to deal with it simply by dividing the display data. Therefore, the burden on the control unit 30 is significantly reduced.

FIGS. 3A to 3C show an example of a driving method when two display units 1C and 1E have a failure, which is the same as the driving method when the one display unit 1F has a failure. In the procedure, as shown in FIG.
The display data is sent to the display units 1F to 1H which are higher than E.

Subsequently, as shown in FIG. 3B, the clocks of the display units 1D and 1E, which are higher than the display unit 1C, and the detour of the data are released, and the clocks of the display units 1F to 1H are separated. 1D,
The display data is transmitted to 1E.

Finally, as shown in FIG. 3C, the display data may be sent to the display units 1A to 1C according to the same procedure as described above. Need only be divided so that is the highest order, and there is no need to create new display data such as deleting or compressing the display data of the failed display unit.

Further, by employing the above-described structure of the display unit 1, the information display device of the present invention enables the following driving method. In the case where only a part of the display unit 1 is to be scroll-displayed in the plurality of display units 1 connected in series, the display data of the scrolling display unit 1 is changed in the conventional example. Must be created for each step of the scroll display, and the display must be performed while changing the scroll display one after another, and the load on the control unit 30 must be very heavy.

On the other hand, in the information display apparatus of the present invention, as shown in FIG. 4, for example, only three display units 1D to 1F out of six display units 1A to 1F connected in series perform scroll display. When the display units 1A to 1C are to be separated from each other, the clock signals of the display units 1A to 1C are cut off.
If 16 clock signals are given to the display, the display scrolls one line at a time, and the control unit 30 performs scroll display only by sending the clock signal without creating display data. Become.

Furthermore, if the function of separating the clock signal for any display unit 1 according to the present invention, the similar bypass function of the shift register 5, and the function of turning off the display element array 2 are combined, the load on the control unit 30 will be conventionally increased. However, a novel display, which is heavy and difficult to implement, can be easily performed without imposing a load on the control unit 30.

[0038]

As described above, according to the present invention, the function of connecting the display data in the shift register to the monitoring data bus for any display unit, the function of disconnecting the clock signal for any display unit, and the same shift The information display device provided with a register bypass function and a display element array 2 turn-off function simplifies the inspection process that is performed every time display is performed to confirm that no failure has occurred in the display unit. The lightening of the load on the control unit, the simplification of the control unit, and the quick inspection can be achieved, and this type of information display device has an excellent effect in reducing the cost and improving the performance. It is.

Further, conventionally, after a failed display unit is detected, display data excluding the failed display unit has to be processed by the control unit, which places a heavy burden on the control unit. The drive method uses a clock signal separation switch and a data detour switch, thereby enabling display excluding display units that have failed without processing to display data, simplifying the mechanism and speeding up operation. And the use of a clock signal separation switch and a data detour switch to provide a novel display method that was previously impossible. Become.

[Brief description of the drawings]

FIG. 1 is a block diagram illustrating a configuration of a display unit that is a main part of an information display device according to the present invention.

FIG. 2 is an explanatory diagram showing a driving method of the information display device according to the present invention in a case where there is only one failure display unit.

FIG. 3 is an explanatory view showing a method of driving the information display device according to the present invention in a case where there are two failure display units.

FIG. 4 is an explanatory view showing another driving method of the information display device according to the present invention.

FIG. 5 is a block diagram showing a conventional information display device.

FIG. 6 is a block diagram showing a display unit of a conventional information display device.

[Explanation of symbols]

1 (A to H) Display unit 2 Display element array 3 Driver circuit 4 Latch circuit 5 Shift register 6, 7, 9, 12 Switch 8, 10, 11, 13, 14 , 15, 16 ... flip-flop 17 ... OR circuit

Continued on the front page (72) Inventor Kunihiko Tamai 5-10-27 Minamiazabu, Minato-ku, Tokyo Inside Anritsu Corporation (58) Field surveyed (Int.Cl. ⁶ , DB name) G09G 3/20 G09G 3 / 32

Claims (4)

(57) [Claims] A display driving circuit including a shift register for accumulating display data for causing a display element array in which display elements are arranged in a matrix of digits and rows to perform lighting display;
A switch for connecting an output of the shift register to a monitoring data bus by a predetermined signal, a switch for switching display data to pass through the shift register or to pass by a bypass by a predetermined signal; A display unit in which a plurality of display units, each of which is provided with a switch for separating a clock signal to the display device and a switch for turning off the display element array by performing the display driving circuit by a predetermined signal, are provided. An information display device, comprising: a control unit for transmitting display data and comparing the monitor data returned by the monitor data bus with the display data to detect a defective display unit. 2. When a failure is detected in any of the display units, an instruction to pass display data is issued to a lower display unit including the display unit in which the failure is detected, and a clock signal is cut off. To output a display signal higher than the display unit in which the failure was detected, and accumulate display data corresponding to the shift register of the display unit higher than the display unit in which the failure was detected. In addition to canceling the separation of the clock signal and the passage instruction of the lower display unit including the display unit where the failure is detected, the clock signal on the higher side than the display unit where the failure is detected is separated, and in this state, The display data on the lower side including the display unit in which the failure is detected is output, and the display data corresponding to the shift register is output. 2. The method according to claim 1, wherein the information is stored. 3. The method according to claim 2, wherein the display unit in which the failure is detected or the display unit at an arbitrary position is turned off by a switch for turning off the display element array. . 4. The clock signal is separated except for an arbitrary number of display units at an arbitrary position of the display unit. In this state, the clock signal of the display element array is separated from an arbitrary number of display units at the arbitrary position. The method according to claim 2 or 3, wherein the display unit performs scroll display by intermittently supplying a clock signal corresponding to the number of rows.