JP2613665B2 - Display device - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a display device having a display panel in which screen units are arranged in a matrix.

[Prior Art] Conventionally, this type of display device, as shown in FIG. 4, the display panel 3 and the screen unit 3 _{11-3 34} comprising a plurality of pixels connected to one another by a transmission cable arranged in a matrix A main controller 1 that stores display data to be displayed on the display panel 3 and sends the display data to the transmission line 2 according to a predetermined display procedure; and a transmission line (for example, RS422) 2.
It is composed of a signal receiving unit 4 made of repeater 5a for transmitting and receiving an input signal input to each screen unit 3 _{11-3 34} of the display panel 3 via a signal receiving unit 4 from the main control unit 1
Data read start signal PEin and clock signal SCK
Together with the display data signals D ₀ to D ₇ to the serial transmission clock SC self display data in each screen unit 3 _{11-3 34}
Data reading start signal PEin then taken on the basis of the shifted data reading start signal PEin at K through the transmission cable was something which is adapted to transmit to the next screen unit 3 _{11-3 34.} Here, screen units 3 _{11 to} 3
_{Reference numeral 34} denotes a plurality of pixels (8 × 4) 30, and 8-bit parallel data is serially transmitted as display data. The arrows in the display panel 3 shows a flashing sequence of the pixels 30, each screen unit 3 _11-3
Transmission between ₃₄ occurs in series.

Now, the display data signal, the data reading start signal PEin, and the clock signal SCK sent from the main control unit 1 are:
Is as shown in Figure 5, is received by the repeater 5 through the transmission line 2, pixel control circuit in a screen unit 3 _{11-3 34} is converted to CMOS level signals handled. Received signal transformed by the repeater 5 is transmitted to the screen unit 3 _{11-3 34} in series via a transmission cable to connect to each other in each screen unit 3 _{11-3 34.} Here, the first screen unit 3 _11, the pixel 30 takes in its display data based on the data read start signal PEin and clock SCK
Performs blinking, and transmits the signal to the next screen unit 3 _12. Similarly, sequentially, capture and display of the display data to the last screen unit 3 ₃₄ is performed.

In this case, the timing of fetching the display data is triggered by the data reading start signal PEin, and this signal is shifted by the clock signal SCK and sent to the next pixel and the next screen unit. Here, the data read start signal PEin to first screen unit 3 ₁₁ is generated at 60Hz or 120 Hz, and is adapted to refresh the display screen.

[Problems to be Solved by the Invention] However, in the above-described conventional example, the pixel data is serially transmitted through one transmission line, and a large number of data capture start signals PEin are generated based on the clock SCK. Since the display data of each pixel 30 is fetched by shifting the number of times (number of pixels), the display reliability when the number of pixels is increased is deteriorated. In other words, if the number of pixels is 8000, to transmit 8000 display data at a synchronous speed of 60 Hz or 120 Hz, it takes 8 msec with the clock SCK at 1 MHz, and to capture 8000 display data, the data reading start signal PEin
Need to be shifted 8000 times by the shift register in synchronization with the clock. This shift operation is a screen unit
3 ₁₁ correctness of operation to be done in ~ 3 ₃₄ is required.
Here, the display data D ₀ to D ₇ and the clock SCK are parallel transmission via a transmission cable to each screen unit 3 _{11-3 34,} the data read start signal PEin are transmitted serially, When noise is mixed, the shift operation of the data read start signal PEin is disturbed and increases or decreases, so that incorrect display data is read and displayed, and there is a problem that display reliability is reduced. This phenomenon is caused by screen unit 3
More incidence _{11-3 34} is increased higher, especially in the case of increasing the screen, considerable costs for noise suppression, such as site adjustment there is a problem that it takes.

Therefore, as shown in FIG. 5, (in the illustrated example, divided in each column) dividing the screen unit 3 _{11-3 34} constituting the display panel 3 in a row or column, and transmission of a plurality of systems corresponding to respective columns It is considered that lines 2a, 2b, and 2c are provided, and display data is transmitted from the main control unit 1 via transmission lines 2a, 2b, and 2c of each system. However, when a plurality of transmission lines 2a, 2b, 2c are provided in this manner, the transmission lines 2a, 2b, 2c
There is a problem that the wiring of b and 2c is costly, and the signal processing of the main control unit 1 is burdened, so that the configuration becomes complicated and the cost increases. That is, the main control unit 1 requires a display data memory, a readout circuit, and a transmission circuit corresponding to each of the transmission lines 2a, 2b, and 2c of each system, so that there is a problem that the cost is increased.

SUMMARY OF THE INVENTION The present invention has been made in view of the above points, and has as its object to simplify the noise countermeasure and reduce the load of signal processing on the main control unit. An object of the present invention is to provide a display device that can be simplified and reduced in cost.

[Means for Solving the Problems] A display device according to the present invention includes a display panel in which screen units each including a plurality of pixels are arranged in a matrix, display data to be displayed on the display panel, and display according to a predetermined display procedure. A main control unit for transmitting data to the transmission line; and a signal receiving unit for receiving an input signal input via the transmission line and transmitting the input signal to each screen unit of the display panel. The display data signal is transmitted serially together with the data read start signal and clock signal, and each screen unit captures its own display data based on the data read start signal shifted by the clock, and then transmits the data read start signal to the transmission cable. In a display device configured to transmit to the next screen unit via the Is connected via a transmission cable to the screen units in the columns, and is provided in correspondence with the screen units in the connected rows or columns. And a distributor for distributing the input signal received to each repeater to form a signal receiving unit, and delay reading in which the data reading start signal transmitted from the main control unit is appropriately delayed corresponding to each row or column. A delay unit for forming a start signal is provided in the repeater, and the delayed read start signal is used as a trigger signal for skipping display data displayed before the row or column displayed by each repeater.

[Operation] The present invention is configured as described above, and connects the row or column screen units constituting the display panel with a transmission cable, and provides each row or column screen unit corresponding to the connected row or column screen unit. A signal receiving unit is formed by a repeater that relays and transmits display data to be displayed on a column screen unit, and a distributor that distributes an input signal received via a transmission line to each of the repeaters, and is transmitted from the main control unit. The repeater is provided with delay means for forming a delayed read start signal obtained by appropriately delaying the read data read start signal corresponding to each row or column. This is a trigger signal for skipping the display data displayed before the column, which makes it easy to take countermeasures against noise. The burden can be reduced, the configuration can be simplified, and the cost can be reduced.

[Example] FIGS. 1 and 2 is shows one embodiment the present invention, a display panel 3 disposed screen unit 3 _{11-3 34} comprising a plurality of pixels in a matrix, the display panel 3 A main controller 1 for storing display data to be displayed and transmitting the display data to a transmission line 2 in accordance with a predetermined display procedure; and a screen unit of a display panel 3 receiving an input signal input through the transmission line 2 3 ₁₁ is composed of a signal receiving unit 4 to be transmitted to to 3 _34, a display data signal D ₀ to D ₇ and serially transmitted from the main control unit 1 to the signal receiving unit 4 together with the data read start signal PEin and the clock signal SCK, each screen unit 3 _{11-3 34} data reading start signal after taken based on the own display data shifted data read start signal at the clock via the transmission cable at the next screen unit 3 In the display device so as to transmit to _{11-3 34,} connected row or column of the screen unit 3 _{11-3 14} constituting the display panel 3, 3 _{21-3 24,} 3 _{31-3 34} with the transmission cable, screen unit of the connected column 3 _{11-3 14,} 3 _21-3
24, 3 _{31-3 34} columns provided corresponding to the screen unit 3
₁₁ ~ 3 _14, 3 _{21-3 24,} 3 _{31-3 34} repeater for relaying transmit display data to be displayed on the 5 _1, 5 _2, 5 _3, an input signal received through the transmission line 2 each repeater 5 _1, 5 _2, 5 ₃ in the distributor 6 which distributes forms the signal receiver 4, suitably delayed to correspond to each column of the transmitted data read start signal PEin from the main control unit 1 Delayed read start signal PEin ₁ , PEi
a delay means for forming the n _2, PEIN ₃ but on the repeater 5 _1, 5 _2, 5 _3. Here, the repeaters 5 ₁ , 5 ₂ , 5 ₃ are balanced RS
422 level signal a is the display data signals D ₀ to D _7, consists of a level converter 10 for converting the data read start signal PEin to nonequilibrium CMOS level signal, a delay unit consisting of counter 11 for counting the clock of a predetermined number The delay time (the number of clock counts) is set by a setting unit such as a dip switch.

Further, it is needless to say that the signal receiving unit 4 is desirably disposed near the display panel 3 from the viewpoint of wiring (in order to reduce the cost as a single transmission line 2 for the most part).

Hereinafter, the operation of the embodiment will be described. Now, the signal transmitted through the transmission line (RS422) 2 from the control unit _{1 (PEin, SCK, D 0} ~D 7) , each relay being distributed by the distributor 6 into three systems device 5 _1, 5 ₂ , is input to the 5 _3. Each repeater
5 ₁ , 5 ₂ , 5 ₃ are a level conversion function for converting an RS422 level signal into a CMOS level signal, and a data reading start signal PEin.
, And delay reading start signals PEin ₁ , PEi
It has a timing generation function to create n _2, PEin _3. Here, the delayed read start signals PEin ₁ , PEin ₂ , PEin
Reference numeral ₃ denotes a trigger signal for skipping display data displayed before the current column, and the counter 11 counts a predetermined number of clocks SCK from the data read start signal PEin to the first display data in the current column. Formed.

For example, if the number of pixels in one column is “500” and the clock frequency is 1 MHz, the delayed read start signal PEin in the second column
₂ may be generated when 500 clocks SCK are counted after the data read start signal PEin is obtained,
In addition, the delayed read start signal PEin ₃ in the third column may be generated at the time when 1,000 signals are counted. Note that the delayed read start signal PEin ₁ in the first column is the data read start signal PEi.
This is the same signal as n. The counter 11 stops the counting operation after the count value matches the preloaded data, and FIG. 3 shows the operation.

[Effects of the Invention] The present invention is configured as described above, and connects the row or column screen units constituting the display panel with a transmission cable, and is provided corresponding to the connected row or column screen units. A main control unit that forms a signal receiving unit by a relay that relays and transmits display data to be displayed on a screen unit in each row or column, and a distributor that distributes an input signal received via a transmission line to each relay; The repeater is provided with delay means for forming a delayed read start signal obtained by appropriately delaying the data read start signal transmitted from the corresponding to each row or column, and each relay displays the delayed read start signal by itself. This is a trigger signal for skipping the display data displayed before the row or column, which can facilitate noise countermeasures, and furthermore, the signal processing of the main control unit. This has the effect of reducing the burden on the processing, simplifying the configuration, and reducing the cost.

[Brief description of the drawings]

FIG. 1 is a schematic configuration diagram of one embodiment of the present invention, FIG. 2 is a main part circuit diagram of the same, FIG. 3 is an operation explanatory diagram of the same, FIG. 4 is a schematic configuration diagram of a conventional example, and FIG. FIG. 6 is a schematic diagram of another conventional example. 1 is a main control unit, 2 is a transmission line, 3 is a display panel, 3 ₁₁
To 3 ₃₄ screen unit, 4 denotes a signal receiving unit, 5 _1, 5 _2, 5 ₃ repeaters, and 6 a distributor.

Claims (1)

(57) [Claims] 1. A display panel in which screen units each including a plurality of pixels are arranged in a matrix, and a main control unit that stores display data to be displayed on the display panel and sends the display data to a transmission line according to a predetermined display procedure. A signal receiving unit that receives an input signal input through a transmission line and transmits the received signal to each screen unit of the display panel. The main control unit sends the display data together with a data reading start signal and a clock signal to the signal receiving unit. Signals are transmitted serially, each display unit captures its own display data based on the data read start signal shifted by the clock, and then transmits the data read start signal to the next screen unit via the transmission cable. In the display device described above, the screen units in rows or columns constituting the display panel are connected by a transmission cable. A repeater that is provided corresponding to the connected screen unit of the row or column and relays and transmits display data to be displayed on the screen unit of each row or column; And a distributor for distributing the data into a signal receiving section, and a relay means for forming a delayed reading start signal obtained by appropriately delaying the data reading start signal transmitted from the main control section in accordance with each row or column. Wherein the delayed read start signal is used as a trigger signal for skipping display data displayed before a row or a column displayed by each repeater by itself.