JPS6134155B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a character display device capable of displaying images in addition to normal character display using a character generator.

In character display devices that use magnetic disks, cathode ray tubes (CRTs), etc., character codes are sent to a refresh memory, and the character codes read from the memory are converted into dot patterns of the corresponding characters by a character generator. of
A method of displaying in addition to a CRT has been adopted, and due to the capacity of the memory and character generator, the characters that can be displayed are limited to some characters such as katakana and alpha characters. However, recently, character generators have been generated on such display devices (hereinafter referred to as normal characters).
There has been a growing demand for displaying not only kanji, figures, tables, etc. in arbitrary shapes. Examples of this include displaying a sales trend table with annotations, as shown in Figure 1a, or displaying an address to check its accuracy when printing an address, as shown in Figure 1b. Or, as shown in Figure c, there may be cases where it is desired to display handwritten characters that were input because the OCR could not read them and rejected them. This is because a graph display is easier to understand at a glance in cases like Figure 1 a, and when shipping addresses use large label printers to print addresses, characters selected according to the input character code are printed. This is because the surest way to have the operator check whether the group or address is incorrect is to display the selected character group as an image on a CRT and have the operator visually check it, as shown in FIG. 1b. Furthermore, with OCR, which reads handwritten characters, it is inevitable that input characters will be unreadable due to clutter, etc., and in order to correct this, it is necessary to display the illegible characters as they are as images and replay them. It is appropriate to ask for input.

In response to such demands, character display devices have appeared that can display images of kanji, figures, etc. in addition to normal character display such as katakana characters.
However, this type of conventional device is equipped with a code memory that stores character codes and a memory that stores images such as kanji and figures in bit (dot) patterns, and outputs from both memories on a CRT. Text and images are displayed by overlaying the information provided.
Therefore, compared to conventional character display devices, the amount of memory is significantly increased and the price of the device is high.

The present invention has been made with the object of reducing the memory required in a character display device capable of displaying such an image pattern, thereby realizing a reduction in the price of the device. That is, in the present invention, one memory is divided into an image pattern storage area and a character code storage area as shown in the left half of FIG. 2, and image patterns such as kanji and figures are stored in the image pattern storage area, while character code information is stored in the image pattern storage area. Store it in the code storage area. Then, address information indicating the boundary between both areas is input to the image address register along with the image pattern and character code input to the memory. On the other hand, the memory is provided with a memory address register, and the address of the memory that is currently being read is stored in the memory address register.The contents of this memory address register and the contents of the image address register are compared by a detector. The detection section detects when the contents of the registers match. When the detection unit detects a match, the input to the CRT is switched from the image pattern read from memory to the character pattern generated by the character generator based on the character code, and the image and characters are displayed on one screen. This is what we are trying to do together.

The present invention will be explained in more detail below along with examples. FIG. 3 is a block diagram of an embodiment of the present invention, in which 1 is a receiving section of a character display device, 21 is a refresh memory, and 3 is address information (3) indicating an area in the memory where an image pattern is stored. 4 is a memory address register that indicates the address currently being read from memory 2; 5 is a match detection circuit that detects a match between both registers; 6 is a CRT horizontal scanning and detection unit. 7 is an AND circuit that takes timing with the detection signal generated from 5; 7 is a flip-flop circuit that controls switching of a switching circuit (multiplexer); 8 is a flip-flop circuit that controls switching of a switching circuit (multiplexer);
9 is a character generator that converts a character code into a corresponding character dot pattern; 9 is the switching circuit that switches between the image bit pattern read from the memory 2 and the character pattern generated from the character generator 8; and 10 is the switching circuit 9. A parallel-to-serial conversion circuit that converts a parallel bit pattern into a serial bit pattern, 1
Reference numeral 1 denotes a display device, in this example, a CRT, which receives the serial bit pattern information obtained in this manner and displays characters or images.

Next, to explain the operation of this apparatus, first, an image and character information to be displayed on a CRT screen, as well as the boundary address, are input to the receiving section 1 of the character display apparatus from an external device (not shown). Of these input information, image and character code information are written into the memory 2, and boundary address information is stored in the image address register 3. As shown in Figure 2, each address in memory 2 consists of 8 bits (1 byte), so input information is stored in units of 8 bits, and addresses 1 to N are image bit patterns. Character code information is written from the information address (N+1) to the final address. Note that a 1-bit modification code (a code that indicates information such as displaying the character brightly or darkly) is usually added to the code, so the character code written to this memory 2 of 8 bits per byte consists of 7 bits. .
Therefore, the image information using this memory 2 is also expressed in units of 7 bits, but in this case, it may be expressed in units of 8 bits by adding a bit for a modification code.

Information input to the memory 2 and register 3 is performed, for example, from the host computer, and when only image information is to be displayed, the boundary address N is the final address of the memory 2, and when only character patterns are to be displayed using the character generator 8, N=0. If you want to display both images and text, the area occupied by the image,
Specifically, the boundary address between the image and the text is an appropriate integer N.

After the characters, image information, and boundary addresses are transferred to the memory 2 and image address register 3 in this manner, display of the characters and images on the CRT screen is started. In response to the start command, the image bit pattern stored in the memory 2 is first read out one address at a time, inputted through the switching circuit 9 to the parallel-to-serial conversion circuit 10, and converted into serial bit information by the circuit. After that, CRT11
is added to display the image pattern on the screen. When displaying a simple image pattern on a CRT, the information at address 1 (8 bits) is displayed as 1
However, in the case of complex image pattern display, one horizontal scan may be used as shown in Figure 2.
One horizontal scanning line may be made up of successive bit information of two or more addresses. When the information in memory 2 is read out sequentially in this way,
The contents of the memory address register 4 indicating the address of the memory being read are sequentially added (+1), and eventually match the boundary address N written in the image address register 3. At this time, the detection circuit 5 outputs a coincidence detection signal and sends it to the AND circuit 6. AND circuit 6 is the horizontal synchronization signal HS of CRT11
and the coincidence detection signal from the detection unit 5,
At the time when both signals are output, that is, when the horizontal scan corresponding to the boundary address N begins, an output is generated and the flip-flop circuit 7 is inverted. This flip-flop circuit 7 is triggered by the vertical synchronizing signal VS and
The output is set to "1" and the switching circuit 9 is switched to the memory 2 side, but when the output from the AND circuit 6 is reversed, the switching circuit 9 is switched to the character generator 8 side. Therefore, the character dot pattern from the character generator 8 is input to the CRT, but since it takes some time to convert the character generator, the input is delayed by the conversion circuit 10 having a buffer function. No video signal is added to the horizontal scan corresponding to this Nth address until the retrace point. During this time, preparations are made, and from the next scanning line onward, a character pattern is displayed on the CRT screen in which the character codes from the Nth address onwards are converted into a 7×9 character dot pattern by the character generator 8. In this way, characters are displayed following the image, and when the scanning of one screen is completed, the vertical synchronizing signal VS is generated, inverting the flip-flop circuit 7 again, and reading the image information from the memory 2,
The display on the CRT, the reading of the character code from the Nth address onwards, the conversion by the character generator 8 and the display on the CRT of the character pattern are repeated, and still images and characters are displayed on the CRT screen.

In the above explanation, the case where the boundary address sent to the image address register 3 is an appropriate number N has been described, but of course, if N is 0, the coincidence detection circuit 3
detects a match from the beginning, so the switching circuit 9 will start displaying the normal character pattern from the beginning, and if N is the final address of the memory 2, the switching circuit will not switch and display the image pattern. will be displayed only.

In addition, when reading an image pattern from memory 2 and displaying it on CRT 11, and when reading a character code from memory 2 and displaying it on character generator 8.
Converts to the corresponding bit pattern and transmits it to the CRT.
11, as mentioned above, the time required for display differs only by the time it takes to go through the character generator 8.
The timing of the display on the CRT 11 is a problem, but the memory readout should always be one or more lines earlier than the CRT display, and the buffer function of the parallel-to-serial conversion circuit 10 can be used to read the final image pattern data. is CRT11
As soon as it is sent to character generator 8
The output from the parallel-to-serial converter circuit
If a method is in place to send data to the CRT, switching will be done smoothly.

In this way, the character display device of the present invention uses the conventional refresh character code memory as the image pattern bit pattern memory, so the memory capacity is significantly reduced compared to the conventional character display device capable of displaying image patterns. It is possible,
Cost reduction can be achieved. Of course, the number of character patterns (depending on the character code) that can be displayed on a CRT is reduced, but as mentioned above, code memory 2 also has cells that store modification codes, so if you use this, the decrease in the number of character patterns can be reduced. This device can be expected to have a wide range of uses, such as displaying unreadable characters on CRTs, displaying address confirmation for address printing, and displaying text data on tables or glasses.

[Brief explanation of the drawing]

1A to 1C are explanatory diagrams of a display screen that displays an image pattern and a normal character display; FIG. 2 is an explanatory diagram that explains the relationship between the memory and the display screen in the character display device of the present invention; and FIG. The figure is a block diagram showing an embodiment of the present invention. In the figure, 2 is a memory, 3 is an image address register, 4 is a memory address register, 5 is a detection circuit, 9 is a switching circuit, and 11 is a display.

Claims (1)

[Claims] 1. A character comprising a memory that stores a character code, a character generator that outputs a character pattern corresponding to the character code read from the memory, and a display that receives the output of the character generator and displays the character pattern. The display device includes an image address register, a circuit for detecting a match between the contents of the address register of the memory and the contents of the image address register, and a circuit for switching the input of the display device to the memory side or to the character generator side. and transmits image information to the memory to store it, and sends address information indicating an image information storage area of the memory to the image address register, so that the contents of the memory address register and the contents of the image address register are A character display device capable of displaying an image, characterized in that when a match occurs and the match detection circuit produces an output, the switching circuit is operated to switch between an image display and a character pattern display on a display. .