JPH03230973A - serial printer - 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 The present invention relates to a serial printer, and more particularly, to a serial printer that performs a printing operation by correcting data for a serial printer having different printing densities in the paper feeding direction.

[Prior Art] When controlling a serial printer,
It is well known that a plurality of different control code systems exist, but the print density in the paper feeding direction, which is the basis of control, that is, the spacing between the rows of print elements that make up the print head, may also differ. Therefore, in a serial printer designed to achieve print density in a specific paper feed direction, if you want a single serial printer to perform printing operations using multiple control code systems, it is necessary to adjust the print density in different paper feed directions. It is necessary to perform corresponding printing.

[Problem and purpose to be solved by the invention] Figure 2 (a)
n printing elements 200 are placed at intervals of m in the paper feeding direction shown in
A serial printer equipped with a print head (hereinafter abbreviated as print head A) arranged at a distance from the print head can perform printing with a width of n*m by one scan of the carriage. In addition, a print head (hereinafter abbreviated as print head B) in which n printing elements are arranged at intervals of ml (however, m'>m) in the paper feeding direction shown in FIG. 2(b) is used. In the serial printer equipped with the above-mentioned printer, printing with a width of n*m' can be performed by scanning the carriage once.

Therefore, if print data created for a serial printer having print head B is printed by a serial printer having print head A, the width (nm'
−nm) blank area will be generated. For example, when printing image data using all n printing elements, if the line feed amount is the same and the printing operation is performed,
In a serial printer having print head B, the printer shown in Fig. 3 (
While the printing result shown in a) is obtained, the serial printer having print head A produces the printing result shown in FIG. 3(b), resulting in a blank area. Conventionally, in order to solve this problem, in the case of a serial printer having print head A, the line feed amount is set to m/m' of the line feed amount of a serial printer having print head B, as shown in FIG. 3(c). I was able to get a print result with no blank areas as shown in the image below.

However, in conventional serial printers, the line feed amount is corrected to the original m/m' when printing, so the print result is 1-m/ml shorter in the paper feed direction than the required print result. It has the problem of becoming. For example, when printing on a print medium with a fixed format, it may be printed on a different - format, or when outputting graphics, it may shrink in the paper feeding direction, causing distortion and resulting in inaccurate printing results. The problem is that it cannot be obtained.

Therefore, it is an object of the present invention to solve the problems of the prior art described above, and to reduce the line feed amount in the paper feeding direction to m /
An object of the present invention is to provide a serial printer that can obtain accurate printing results by performing printing operations without correcting m'.

[Means for solving the problem] Having n printing elements at m intervals in the vertical direction,
In a serial printer that has a print head that prints a width nm in the vertical direction with one carriage scan, the print head prints a width nm' in the vertical direction with one carriage scan transferred from the host device (where m<m')
A print data determining means determines whether or not the print data to be printed is corrected and printed, and each of the print data determined by the print data determining means is stored separately. dot adding means for adding print data in the vertical direction to the print data to be corrected and printed in the vertical direction stored in the one storage means; The present invention is characterized by comprising a print control means that prints print data by dividing it into a plurality of lines.

[Operation] The input print data is checked by the print data discrimination means.
The dots are classified according to whether or not it is necessary to correct and print the dots, and if it is necessary to correct the dots, additional dots are generated by the dot correction means and the printing operation is performed.

[Embodiment] FIG. 4 shows the configuration of a serial printer of the present invention. Data input from a host device (not shown) through the interface section 20 is stored in the input buffer 21 - first. The control unit 23 sequentially reads out the data stored in the input buffer 21, and if it is character data, converts it into a character pattern to be stored in the character generator 22, and then stores it in the line buffer 2 as print data. If it is a print command, the carriage drive unit 8 and paper feed drive unit 9
Further, the print data stored in the line buffer 1 is sent to the print Δ and RAD drive section 11, and printing is performed on a sheet (not shown) through the print head 25.

Here, the print data discriminating section and dot adding section in the present invention belong to the control section 23, and will be explained in detail below.

FIG. 5 is a diagram showing the operation of the print data discrimination section,
It determines whether data input from the host device should be printed by adding dots in the paper feeding direction.

Specifically, it is determined whether the input data is a character code or image data (FIG. 5 41), and if it is image data, the data is stored in the row buffer 2 (FIG. 5).
Figure 44). Furthermore, if it is a character code, it is determined whether it is a ruled line code or not, and if it is a ruled line code, it is stored in the line buffer 2 in the same way as image data. In other words, the ruled line code is treated in the same way as image data. Codes determined to be normal character codes rather than ruled line codes are stored in the line buffer 2 (FIG. 5, 43), and the process returns to the next input data processing. Also, after storing the data in row buffer 2,
FLAG indicating that data has been stored in row buffer 2
=1 (Fig. 5, 45).

FIG. 5 is a diagram showing the operation when a print command is input;
FIG. 1 is a diagram showing the flow of data.

When a print command is input from the host device, the print control unit 7
enters the FLAG state and determines whether there is data stored in row buffer 2 (FIG. 6, 51).
. When FLAG=O, there is no data to be printed in the line buffer 2, that is, only the print data stored in the line buffer 2 is transferred to the head drive unit 11 without dot correction. The carriage is driven by the carriage drive unit 8 to print the - line (Fig. 6-5).
2). After printing is completed, the paper feed drive unit 9 feeds the paper by the amount of line feed specified by the host device.

Next, a case where FLAG=1 and print data exists in the line buffer 2 will be described. The print control unit 7 generates print data obtained by adding correction dots to the print data stored in the line buffer 2 by the dot adding unit 6, and print data that is the sum of the print data stored in the line buffer 1. It is sent to the head drive unit 11 and performs the first printing operation (FIG. 6, 45).

Here, the detailed operation of the dot adding section 6 will be explained using FIG. The serial printer of the present invention has a print head in which n printing elements are arranged at intervals of m in the paper feeding direction, and print data input from a host device is transmitted through the n printing elements. Assume that the data is for a serial printer having print heads arranged at intervals m'. For ease of explanation here, n-24
, m/m'=8/9. In order to print 24 dots of print data in the paper feed direction input from the host device using the serial printer of the present invention, the number n' of dots in the paper feed direction is set to n'=n/(m/m'), that is, n'
It is necessary to print it as =27 dots l-. The dot adding section 8 adds 3 dots to the print data of 24 dots in the paper feed direction.
Dot correction dots will be added. That is, an operation is performed in which dots are added at a rate of 1 dot for every 8 dots of print data. The dots to be added are: - As an example, as shown in Figure 7, the product of the 4th and 5th dot data from the top of the print head is placed between them, and the 12th dot is placed in the middle. and 13th, 200th 2
It operates to add a total of three dots at the first intermediate position.

Therefore, the print control unit 7 selects the upper n = 24 dot data of the print data of n' = 27 dots in the paper feed direction generated by the dot adding unit 8, and selects the data of the first n = 24 dots along with the normal character data. Perform printing. After printing is finished,
Prior to the second printing operation, paper is fed in three steps in units of m (FIG. 6, 55). Thereafter, the print control section 7 selects the lower three dots of the 27-dot print data generated by the dot addition section 8, transfers them to the head drive section 11 for printing (Fig. 6, 56), and then selects them from the host device. The paper is fed by 3 steps less than the specified line feed amount (Fig. 6, 57), and the printing operation for this line is completed.

FIG. 8 shows the correspondence between the printing results obtained by the operations of each section described above and the printing data stored in each line buffer. FIGS. 8(a), 8(b), and 8(c) are diagrams showing the correspondence between print data 301, 302 stored in each line buffer and a print result 303 when dots in a print line are not corrected. FIGS. 8(d) and 8(e) show print data stored in each line buffer when there is data to correct and print dots in a print line, and FIG.
f) (g) are the first and second printing results 3 respectively
04,305.

[Effects of the Invention] As explained above, in the present invention, the dot adding means prints print data created for a serial printer having a different print head while adding dots and correcting the print data, thereby improving paper feed. In addition to being able to obtain similar printing results in terms of direction, it is also equipped with a means to determine whether or not the printing data should be added with dots.
Good printing results can be obtained without unnecessarily increasing the number of printings.

[Brief explanation of drawings]

FIG. 1 is a diagram showing the configuration of the present invention, and FIGS. 2(a) and (b) show printing elements m and m', respectively.
FIG. 3(a) is a diagram showing print heads arranged at intervals of
(b) and (c) are diagrams showing printing examples in the prior art; FIG. 4 is a diagram showing the configuration of the serial printer of the present invention; FIG. 5 is a diagram showing the operation of the print data discrimination means; FIG. 6 is a diagram showing the operation when a printing command is input, FIG. 7 is a diagram showing the operation of the dot adding means, and FIGS. 8(a), (b),
(c), (d), (e), (f), and (g) are diagrams showing printing examples in the present invention. ” ni

Claims (1)

[Claims] having n printing elements spaced apart by m in the vertical direction;
In a serial printer that has a print head that prints a width of nm in the vertical direction with one carriage scan, a print with a width of nm'(m<m') in the vertical direction is performed by one carriage scan transferred from the host device. Two data storage means for correcting print data to be printed and determining whether or not the print data is to be printed by a print data determining means, and separately storing each print data determined by the print data determining means. dot adding means for adding print data in the vertical direction to the print data to be corrected and printed in the vertical direction stored in one of the storage means, and one line of printing transferred from the host device. 1. A serial printer comprising: printing control means for printing data by dividing it into a plurality of lines.