KR940007479B1 - How to delete adjacent dots in the printer - Google Patents

Abstract

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Description

How to delete adjacent dots in the printer

1 is a system diagram for carrying out the present invention.

2 is a flow chart of the present invention.

3 is a schematic diagram of a character generation buffer.

* Explanation of symbols for main parts of the drawings

10: input unit 20: CPU

30: program ROM 40: font ROM

50: ram 60: head drive unit

70: head

The present invention relates to a printing method of a printer, and more particularly, to a method of deleting adjacent dots when printing.

In general, a printer prints a character corresponding to a character code input using a font ROM. In this case, font fonts (FONT: LQ, DRAFT, letter gothic COURIER, etc.) are stored.

If the printer implements the character as described above, adjacent dots are generated. If the printing is performed in the presence of the adjacent dots, the printer head may be fatally damaged. Therefore, it is necessary to remove the adjacent dots as described above. In the conventional printer, when the character is implemented, the adjacent dots are deleted by comparing each bit. However, the conventional adjacent dot deletion method as described above has a problem in that the dot deletion time becomes long and the printing speed is lowered, thereby lowering the printing efficiency.

Accordingly, an object of the present invention is to provide a method for improving printing speed by deleting adjacent dots in bytes when deleting adjacent dots in a printer.

Hereinafter, the present invention will be described in detail with reference to the drawings.

1 is a system configuration diagram for carrying out the present invention, an input unit 10 for receiving various character codes, a CPU 20 for controlling the overall operation of a printer, and a program ROM 30 storing the control program. ), The font ROM 40 storing various general character fonts, the RAM 50 temporarily storing data generated during program execution, and the head 70 under the control of the CPU 20 The head drive unit 80 is composed of.

2 is a flowchart of deleting adjacent dots according to the present invention, a process of reading a character to be printed from a font-ROM and storing it in a character generation buffer; and checking whether there is an adjacent dot after performing the storing process; Analyzing a character type when there is a neighboring dot, and setting a counter variable for deleting the neighboring dot in units of bytes, and reducing the counter variable after performing the set process, and storing dot data of the current byte and dot data and the adjacent byte. In comparison, the process consists of deleting adjacent dots.

3 is a configuration diagram of a character generator buffer of the RAM 50, and FIG. 3 is a configuration diagram of font data of a character generation buffer in a draft general character of 24 × 16, and FIG. The starting address of each byte data in Fig. 3A is shown.

Based on the above-described configuration, the present invention will be described in detail with reference to FIGS.

Only the general text font is stored in the font ROM 40, and when the character font data stored in the font ROM 40 is to be printed out, the general text font of the font ROM 40 is specified in the RAM 50. After storing in the character generation buffer assigned to the area, the adjacent dot of the stored character font is deleted and converted into the character font for printing. Then, the CPU 20 outputs the converted character font data to the head driver 60, and the head driver 60 drives the head 70 to print the character font.

As described above, a process of deleting adjacent dots of a general character font will be described in detail.

First, the CPU 20 analyzes the character code received through the input unit 10 to determine the character to be printed, and then reads the font data of the font ROM 40 corresponding to the character code in step 201 (202). In the step S), the memory is stored in the character generation buffer allocated to the RAM 30 as shown in FIG. That is, the character generator buffer is an area for storing font data of general characters and is allocated to a specific area on RAM 30. When step 202, the font data of general characters to be printed is stored. Stored.

In step 203, the CPU 20 checks whether there is a dot adjacent to the font data. In this case, when there are adjacent dots in step 203, a counter variable for deleting the adjacent dots is set in step 204. Looking at the configuration of the general character font, the draft font is composed of 24 (V) × 12 (H), the LQ font is composed of 24 (V) × 36 (H). In the case of the draft font, " 12 " means printing 12 columns of a 24-pin printer, and one column is IX, IX + 1, IX + 2 consisting of 3 bytes (3 x 8 = 24 bits). It consists of data of an address.

In addition, in the case of the LQ font, "36" means to print 36 columns of the 24-pin printer, the rest is the same as the draft font. 3A shows an example of font data in the character generation buffer, which shows the letter "A" of the draft font, and illustrates that there are adjacent dots.

In this case, as shown in FIG. 3B, the start address of the character generation buffer shown in FIG. 3A is stored in the index register.

To delete the adjacent dots of the general character port data as described above, a counter variable is first set. At step 204, first, 33 is set as the counter variable. This is a variable for comparing adjacent dots in bytes, and multiplies the number of bytes by deleting the first column.

That is, in the case of the draft font, since one column is 3 bytes (24 bits) and 12 columns, it can be seen that (12-1) x 3 = 33. In the case of the LQ font, since one column has 3 bytes (24 bytes) and 36 columns, it can be seen that (36-1) x 3 = 105. Therefore, in the case of the draft font, 33 bytes of (IX + 0) to (IX + 32) data are compared with the dot data of the adjacent bytes in byte units to delete the adjacent dots.

Therefore, the CPU 20 first sets 33 as the counter variable in step 204, and then checks in step 205 whether the font data is a draft font or an LQ font. At this time, if the draft font is obtained, the counter variable 33 is taken as it is and the adjacent dots are deleted through the steps (206) to (210), and if the LQ font is set to the counter variable to 105 in step (211), then (206) to (210 Steps are performed to delete the adjacent dots.

Here, the deletion process of the adjacent dot will be described.

First, in step 206, the CPU 20 reads the 1-byte dot data at the position designated by the current index IX and stores it in the A register, and then designates the IX + 3 which is adjacent to the storage dot data of the A register. Reads one-byte dot data at the position and ORs the two dot data by byte unit. The byte data of the OR operation is stored in the A register. Thereafter, in step 207, the byte data of the A register stored as the logical sum is inverted, and the dot data and the dot data of IX + 3 positions, which are adjacent bytes, in the unit of bytes of the inverted A register are ANDed to perform A operation. Store in a register. At this time, the adjacent dot is erased and stored in the A register. Thereafter, in step 208, the dot data of the A register is stored at a location designated by (IX + 3), and the index IX is increased by one. After deleting the one-byte adjacent dot data, the CPU 20 decrements the counter variable by one in step 209 and then checks whether the counter variable is zero in step 200.

If the counter variable is " 0 " in step 210, the 33-byte dot data is deleted by comparing with the dot data of adjacent bytes. If the routine is not completed, the dot data in the byte unit to be deleted still remains. Steps 206 to 208 are repeated to delete the adjacent dots.

Therefore, when deleting adjacent dots in comparison with a byte unit, the method repeats 33 times in the case of the draft font and 105 times in the case of the LQ font through the processes (206) to (210).

As described above, when the adjacent dots are deleted in the printer, the deletion processing time can be shortened to improve the printer speed, and the lifetime of the print head can be extended by deleting the adjacent dots.

Claims (3)

A method of deleting adjacent dots in a printer, the method comprising: reading a character of an m-byte × n column printed by a font ROM in a character generation buffer; and checking whether there is an adjacent dot after performing the storing process; Analyzing a character type when there is a dot, and setting a counter value for deleting adjacent dots in byte units, and reducing the counter value after performing the set process, and comparing the dot data of the current byte and the dot data of the adjacent byte. The method of deleting adjacent dots of the printer, characterized in that the process of deleting the adjacent dots. The printer according to claim 1, wherein the counter variable set process is performed to set a counter value by multiplying {(n-1) x m} the number of bytes by the remaining columns from which the first column is deleted from the font configuration of the character font. How to delete adjacent dots. 3. The method of claim 2, wherein the deleting of the adjacent dots comprises performing a logical OR operation on the dot data at the current byte index position and the dot data at the adjacent byte index position, inverting the dot data in the logical byte unit unit, and Performing a logical AND operation on the inverted byte data of the dot data and the dot data of the adjacent byte index position, deleting the adjacent dot, storing the deleted byte data of the dot data in the adjacent byte index position, and The method of deleting adjacent dots of a printer, characterized in that the process of repeating the process after increasing the index value after performing the process.