JPH0554153B2 - - Google Patents

Description

[Detailed Description of the Invention] [Technical Field of the Invention] The present invention provides an impact dot type serial
The present invention relates to an improved bar code printing method that allows a printer to print bar codes with high dot density.

[Prior art and problems]

In impact dot type serial printers, when the current flowing through the print head exceeds a certain level due to power supply constraints, the print head hammer
The voltage that drives the pins drops, causing blurred printing or missing dots. In order to prevent such blurred printing and missing dots, conventional impact dot type serial printers stop printing after a voltage drop is detected or when the total number of dots counted before printing exceeds a certain value. A method was adopted in which the process was divided into three or four times. However, in this case, a decrease in throughput and a decrease in print quality due to divided printing were unavoidable. In particular, when printing bar codes, depending on the type of bar code, the black bar area may be considerably larger than the white space. There is a possibility that many harmful effects may occur.

Figure 1 shows that the printer's printing duty is MAX50.
% capacity and a bar code with a duty of 60% is printed using the conventional method. The print head is a 24-pin type, usually
All 24 pins are used for printing, but when the hammer pin drive voltage drops, only 8 of the 24 pins are used for printing. Therefore, if you use 24 pins, you can print a bar/printer in one go.
The code will be printed three times in one direction.

[Purpose of the invention]

The present invention is based on the above considerations, and includes:
Impact printing that does not allow continuous printing with high dot density
It is an object of the present invention to provide a bar code printing method that enables a dot-type serial printer to print bar codes with high dot density while minimizing throughput and deterioration in print quality.

[Structure of the invention]

Therefore, the bar code printing method of the present invention is applicable to a system that includes a computer as a main body, a driver and mechanism section of an impact dot type serial printer, and a printer control circuit that controls the driver and mechanism section. In the bar code printing method, the printer control circuit calculates the bar code dot density in the horizontal direction of the bar code to be printed when printing the bar code according to instructions from the computer; When the obtained bar code dot density is not greater than a predetermined value and the number of remaining dots in the vertical portion of the bar code to be printed that remains unprinted is greater than the total number of pins of the print head. performs processing to print a bar code using all pins of the printing hand, and if the bar code dot density determined above is greater than the predetermined value and the number of remaining dots is {total number of pins x (predetermined (printable dot density/bar code dot density to be printed)} If larger than a, process to print the bar code using a number of pins on the print head. It is characterized in that it is configured to perform.

[Embodiments of the invention]

Hereinafter, the present invention will be explained with reference to examples.

To summarize, the embodiment of the present invention focuses on the uniformity of the density of bar codes in the vertical direction, and when printing a bar code, calculates the bar code dot density and determines whether the bar code dot density is as specified. If it is not larger than the value, print all pins of the pin number N, if it is larger, print the a pin (a < N),
By feeding the paper by the number of printed pins and repeating this a required number of times, a bar code of the specified vertical width is completed.

Figure 2 shows that the printer's printing duty is MAX50.
% capacity, a bar code with a duty of 60% is printed using the bar code printing method of the present invention. This bar code is 4
Printing is performed by performing unidirectional printing twice, but the first three printings are performed using 20 pins out of 24 pins (24 pins x 50% ÷ 60% = 20 pins), and the last One printing is performed using 12 pins out of 24 pins.

FIG. 3 shows an example of a bar code order format. The bar code order consists of a code indicating that it is a bar code order, a byte count, the type of bar code, the number of vertical dots, and bar code data. The types of bar codes are:
JAM, NW-7 (2of7), Industrial 2of5,
Examples include Matrix 2of5 and Interleaved 2of5. This bar code order is sent from the main computer to the printer.

FIG. 4 is a diagram showing an example of the hardware configuration of a printer used in the present invention. In Figure 4, 1 is a microprocessor, 2 is a RAM, 3 is a control memory, 4 is an output port, 5 is an input port, and 6
is the console panel, 7 is the driver and mechanical part of the impact dot type serial printer, 8 is the interface control circuit, 9 is the address decoder, 10 to 12 are the bidirectional driver/receiver, and CNT is the printer control circuit. are shown respectively. The microprocessor 1 executes programs stored in the control memory 3.
The RAM 2 has various buffers such as a communication buffer and a print buffer, and a work area. The control memory 3 stores programs and tables. The output port 4 is for outputting data to the console 6 or the driver and mechanism section 7, and the input port 5 is for inputting data from the console 6 or the driver and mechanism section 7. The interface control circuit 8 controls writing data sent from the computer main body to the RAM 2 and reading data stored in the RAM 2 and sending it to the computer main body. The address decoder 9 instructs the output port 4 where to output data, and instructs the input port where to read data. The part surrounded by the one-dot chain line constitutes the printer control circuit CNT.

FIG. 5 is a diagram showing an example of the configuration of a print buffer. 1st byte, 4th byte of print buffer,...
The 3n-2nd byte corresponds to the 1st to 8th pins of the print head, and the 2nd byte of the print buffer,
The 5th byte, ...3n-1 byte corresponds to the 9th to 16th pins of the print head, and the 3rd byte, 6th byte, ...3n byte of the print buffer correspond to the 17th to 24th pins of the print head. It corresponds to Note that n indicates the dot position in the horizontal direction.

FIG. 6 shows an example of an Industrial2of5 bar code table. Address 0 (first address) of this table stores the code "110" representing the start character, and address 1 stores the code "101" representing the stop character.
"00110" representing character 0 is stored in address 2, and a code "10001" representing character 1 is stored in address 3. The following is as shown in the figure. In the Industrial2of5 bar code, the "1" part is 6 dots black,
The "0" part is printed in the form of two black dots, and the space between the blacks is two white dots (space between elements).

FIG. 7 is a flowchart illustrating bar code processing performed by printer control circuit CNT. This step is performed by executing a bar code printing program stored in the control memory 3.

When the power is turned on, normal processing is performed.

Check to see if a bar code order has been sent. If Yes, perform the process, No
When , return to processing.

Clear the print buffer.

Determine bar code type.

A start mark is created on the printing buffer while referring to the bar code table corresponding to the specified bar code type.

A bar code printing pattern for the specified number of characters is created on the printing buffer while referring to the corresponding bar code table.

Create an end mark (stop mark) on the print buffer while referring to the corresponding bar code table.

The total number of dot rows from the start mark to the end mark of the print buffer is calculated and stored in the K register.

The number of dot strings of "1" in the print buffer is calculated and stored in the L register.

Count the number of dots in the vertical direction and store this in the P register.

Store the printable dot density (%) of the printer in the N register.

Contents of L register ÷ Contents of K register x 100
is greater than the contents of the N register. If Yes, perform the process; if No, perform the process.

24 x Contents of L register ÷ Contents of L register x
Calculate the contents of the K register divided by 100, store the result in the a register, and perform the following processing.

Store the number “24” in register a.

Check whether the contents of the P register are greater than the contents of the a register. If Yes, perform the process; if No, perform the process. What,
Yes means it's not final yet.

Clear 24-a dots from the print buffer.

The contents of the a register are subtracted from the contents of the P register, and the result of this subtraction is stored in the P register.

Print the print buffer data.

The paper is fed by a dot and returns to the process.

Clear 24-P dots from the bottom of the print buffer.

Print the print buffer data.

Feed the paper by P dots and return to .

Furthermore, once the bar code type is decided,
There are some bar codes (such as Industrial 2of5) where the dot density is determined automatically, but there are some bar codes (such as Industrial 2of5) that have a considerable difference in dot density depending on the content of the bar code.
In Matrix2of5 etc., 4 and 5 have high dot density,
9), which is characterized by a low dot density, also exists, so the present invention is generally effective. Also,
Depending on the characteristics of the printer, Y% up to X dot row
In some cases, the printable dot density value varies depending on the printing width, such as printing with a dot density of It is sufficient to vary Y (the value of N in the flowchart). Furthermore, there are cases where the value of From the left end of the printing buffer, print the bar code every 1 dot row by X dot width.
Y' may be calculated while changing the calculation range of dot density Y', and the maximum Y' up to the right end of the calculation range may be adopted as the bar code dot density.

〔Effect of the invention〕

As is clear from the above description, the bar code printing method of the present invention has the remarkable effect of minimizing the reduction in throughput and print quality.

[Brief explanation of drawings]

FIG. 1 is a diagram showing an example of a bar code printed using the conventional bar code printing method, and FIG. 2 is a diagram showing an example of a bar code printed using the bar code printing method of the present invention. , FIG. 3 is a diagram showing an example of a bar code order format, FIG. 4 is a diagram showing an example of a hardware configuration of a printer used in the present invention, and FIG. 5 is a diagram showing an example of a print buffer configuration. Figure 6 is a diagram showing an example of an Industrial2of5 bar code table, Figure 7 is a flowchart explaining the bar code printing process performed in the printer control circuit, and Figure 8 is a diagram showing printable dots. FIG. 6 is a diagram for explaining a method for determining bar code dot density when the density is defined only in a shorter range than the bar code width. 1...Microprocessor, 2...RAM, 3
...Control memory, 4...Output port, 5...Input port, 6...Console panel, 7...Impact dot type serial printer driver &
Mechanism section, 8...Interface control circuit, 9...
Address decoder, 10 to 12...bidirectional driver/receiver, CNT...printer control circuit.

Claims (1)

[Claims] 1 A bar code printing method in a system comprising a main body computer, a driver and mechanism section of an impact dot type serial printer, and a printer control circuit that controls the driver and mechanism section, which When printing a bar code according to the instructions of the above-mentioned computer, the circuit calculates the bar code dot density in the horizontal direction of the bar code to be printed, and sets the obtained bar code dot density to a predetermined value. If the number of remaining dots in the vertical portion of the bar code to be printed is larger than the total number of pins of the print head, all pins of the print head are used to print the bar code. The bar code dot density determined above is greater than the predetermined value, and the remaining number of dots is {total number of pins x
(Predetermined printable dot density/bars to be printed)
code dot density)}a
, the bar code printing method is configured to perform processing for printing the bar code using a number of pins of a print head when the number of pins is larger than .