JPS60260993A - Character display - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a character display, and particularly to a 1C panel type character display.

(Prior art) It is common practice to equip portable devices with a display to display numbers and alphabets, but unlike stationary and Tojo-type devices, in the case of portable devices, the operator The argument is that the viewing angle from which the display is viewed is not constant.

FIG. 1 is a block diagram showing an example of a character display using a seven-segment light emitting diode type display board according to the prior art. In Figure 1 Kk, 11 is a column drive circuit, 12 counters, and 13 a display board.

14 is a row driving circuit, 15 is a character generator, 1
6 is a RAM. Four-digit numerical information is stored in the RAM 16 in BOD format. counter 12 to binary 2
A digit address signal is output, and numerical information is sequentially read out from the RAM 16 by the output of the counter 12.
The column 1 drive circuit 11 is sequentially scanned from the left. RAM16
The numeric information in Bol) format read out from the character generator 15 as shown in FIG.

As a result, a normal display as shown in Fig. 3 (al) is obtained, but when the display is viewed from the opposite position, it is shown in Fig. 3 (b).
The display becomes overturned as shown in the figure, and the reading becomes extremely φW.

As explained above, according to the prior art, characters may be inverted, so for example, when a display is provided on the head of a pager, it depends on which side it is placed in the pocket, front or back. There was a problem in that the displayed characters could be upside down.

(Object of the Invention) An object of the present invention is to add a logic inversion circuit to the output of the counter and add an upright/inverted instruction signal to perform column drive scanning according to the instruction, and also to input the input of the character generator to the upright/inverted direction. /An object of the present invention is to provide a character display device which eliminates the above-mentioned drawbacks by adding an inverted instruction signal to change the displayed characters from upright to inverted, and which is configured so that upright/inverted can be instructed by switch operation.

(Structure of the Invention) A character display according to the present invention includes a display board, a row drive circuit, a column drive circuit, a counter, a character generator,
It is equipped with a RAM and a logic inversion circuit, and is configured so that the order of column scanning can be reversed and the top and bottom of display characters output from a character generator can be reversed.

The display board has a matrix structure and is used to display characters.

The row drive circuit is for driving the rows of the display panel.

The column drive circuit is for driving the columns of the display board.1.・
It is an enemy.

The counter is used to generate a digital signal for selecting one column in the column drive circuit.

The character generator is for providing glyph signals of display characters to each row of the row drive circuit.

The RAM is for providing addresses corresponding to display characters to the character generator.

The logic inversion circuit is used to switch the output logic of the counter from positive logic to negative logic and provide it to the column drive circuit.

(Example) Next, the present invention will be explained in detail with reference to the drawings.

FIG. 4 is a block diagram showing one embodiment of a character display device according to the present invention. In FIG. 4, a 21-digit column drive circuit,
22 is a counter, 23 is a display board, 24 rows are 51 drive circuits, 25 is a jd character generator, and 26 is a 1 (, AM
, 27 is a logic inverting circuit, and 281-inch scale. The difference between FIG. 4 and FIG. 1 is that a logic inversion circuit 27 is added to the output of the counter 22, and a new A for instructing the character generator 25 to stand upright/inverted.
This is due to the addition of four manpower.

The operation of the character display device according to the present invention will be explained below with reference to FIG.

When the switch 28 is in the "o" position, the K counter 2
Since the output of 2 is positive logic, the scanning order of R1AM26 and the scanning order of column drive circuit 21 are different from 1'1'
It is exactly the same as in the case of '. Switch 28 is "0"
When the character generator 25 is at the position A4=0, the output of the character generator 25 is exactly the same as that shown in FIG. As a result, the order and direction of the characters displayed on the display board 23 are as shown in FIG.
The output of 2 becomes negative logic. That is, as shown in FIG. 5, this depends on the scanning order of the RAM 26 and the column drive circuit 21.
This is nothing more than reversing the relationship with the scanning order of . Therefore, the characters displayed at the left end when the switch 28 is in the "0" position will be moved to the right end. The output of the character generator 25 is A as shown in FIG.
If 4=1, the top and bottom will be reversed and you will stand upside down.

As a result, the contents of the display are reversed vertically and horizontally, resulting in the display shown in FIG. 3(b), which can be read correctly when viewed from the opposite direction.

The present invention has been described above in the case of a display board consisting of 7 segment type 4 characters and - lines, but as long as the - lines are present, the same applies to cases where the number of characters is expressed by a power of 2, such as 8 characters or 16 characters. There is no doubt that it can be applied. This is a great feature, and can be applied not only to 7-segment type display boards but also to dot matrix display boards.

(Effects of the Invention) As explained above, in the present invention, a logic inversion circuit is added to the output of the counter to add an instruction of upright/inverted, and column drive scanning is performed according to the instruction, and the input of the character generator is By adding an instruction signal for erecting/inverting the displayed characters to make the displayed characters erect or inverted, it is possible to instruct erecting/inverted by operating a switch, which has the effect of improving the operability of character display.

[Brief explanation of drawings]

FIG. 1 is a block diagram showing an example of a character display device according to the prior art. FIG. 2 is a diagram showing an example of the output of the character generator shown in FIG. 1. FIG. 3 is a diagram showing the orientation of character display. FIG. 4 is a block diagram showing one embodiment of a character display device according to the present invention. FIG. 5 is a diagram illustrating the operation of the logic inversion circuit shown in FIG. 4. FIG. 6 is a diagram showing an example of the output of the character generator shown in FIG. 4. 11, 21... Column drive circuit 12, 22... Counter 13, 23... Display board 14, 24... Row drive circuit 1 15, 25... Character generator 16, 2
6...RAM 27...Logic inverting circuit 28...Switch agent Patent attorney I Noro Repeated piece 1 diagram FλF2 F-15] θθθl 0 l l θθρθ 01) 10 /10 1101 θθ 11 / ///ρ θ l θl θθ 01110/1 ρ 1/f f/71 If ρl lρ 1011/71 ρ 7'/7 /ITρ θlθ /IIρ,'//,'/11! θθ+ rtrt pH Figure 3 (a) (l:l)

Claims (1)

[Claims] a display board for displaying characters having a matrix structure; a row drive circuit for driving the rows of the display board; a column 5 drive circuit for driving the columns of the display board; and a column drive circuit for driving the columns of the display board. a binary counter for generating a digital signal for selecting a column in the circuit; a character generator for providing glyph signals of display characters for each row of the row driving circuit; and @ for the character generator. A RAM for giving an address corresponding to the displayed characters,
and a logic inversion circuit for switching the output logic of the counter to positive logic or negative logic and applying it to the column drive circuit, which is capable of reversing the order of column scanning and the display output from the character generator. A character display device characterized by being configured so that the top and bottom of the characters can be reversed.