JP2876628B2 - Printing device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[Overview] Regarding a dot printer, the purpose of the present invention is to provide a dot printer in which a fraction of a line feed amount does not accumulate, and has a bitmap memory, a printing unit, and a control unit, and at least one of a graphic and an image is provided. A printing apparatus for superimposing and printing bitmap data including character data, wherein the bitmap memory includes a data development area for developing the bitmap data, and one line of character data to be printed. The character expansion line buffer for pattern expansion and the data to be transferred to the printing unit
A transfer line buffer for storing the number of lines, wherein the printing unit prints the data transferred from the transfer line buffer, and the control unit includes a transfer line buffer from the transfer line buffer. The printing unit prints the transferred data, wherein the printing unit expands the bitmap data in the data expansion area, and prints the character data in a case where print lines of the character data are equally distributed in the print scheduled area. With respect to the number of dots in the line feed direction per line, a value L of an integer part and a value l of a fraction part are obtained, and an integer m and a value of the k are calculated such that a product k of the l is an integer. Select k rows from m consecutive rows to be printed,
The k lines are composed of (L + 1) dot character data in the line feed direction, the character data is developed in a character development line buffer and edited, and the data in the character development line buffer is copied to the transfer line buffer. The content of the bitmap memory is cut out by the same number of dots in the line feed direction as the character data and is superimposed on the transfer line buffer, the data in the transfer line buffer is transferred to a printing unit, and a print instruction is issued.
The remaining (mk) lines to be printed are composed of character data of L dots in the line feed direction, the character data is developed in a character development line buffer and edited, and the data in the character development line buffer is transferred to the transfer line. In addition to copying to the buffer, the contents of the bitmap memory are cut out by the same number of dots in the line feed direction as the character data and superimposed on the transfer line buffer, and the data in the transfer line buffer is transferred to the printing unit and printed. Is configured to give the instruction of (1). [Industrial Application Field] The present invention relates to a dot printer for printing characters, figures, and images as a dot matrix. 2. Description of the Related Art In a dot printer such as a dot impact printer, the dot density and the minimum line feed amount that can be output are determined at the time of design, and cannot be freely changed during printing. On the other hand, when printing characters, the number of print lines or the line pitch per inch is specified, but the specified value may not correspond to the dot density and the line feed amount. For example, using a printer having a dot density of 160 dots / inch, the number of dots per character in the vertical direction is 24 dots, and the minimum line feed amount is 1/160 inch, the line pitch is set to 6 dots / inch.
It is assumed that printing is performed by specifying a line. In this case, the number of dots corresponding to the line feed amount, that is, the number of dots required per line is 160 ÷ 6 ≒ 26.6666 (dots), which is a value obtained by dividing the number of dots per inch by the number of lines, and is not an integer value. Since line feed cannot be performed with such a value, if a fractional part is rounded off and printed at 27 dots / line, errors per line are accumulated, and when a graphic or an image and a character are superimposed and output, the error occurs. Then, the relative positional relationship between the character and the figure or image is shifted. Further, when printing only characters, there is no problem in the relative positional relationship between the characters and the graphic or image, but if the above-described accumulated error is large, a situation may occur in which the print target area is protruded. [Problem to be Solved by the Invention] As described above, in the conventional dot printer, when the number of dots corresponding to the line feed amount has a fraction and the place is rounded, errors of the fraction accumulate and are displayed on the bit map. This is a problem particularly when the drawn contents and the characters are superimposed and output. In recent years, the need for a printing device has diversified, and characters and graphics and images are often superimposed, and there is a tendency to output printed contents more accurately. There is a strong demand for the emergence of printers. SUMMARY OF THE INVENTION It is an object of the present invention to provide a dot printer in which fractions of line feed are not accumulated. [Means for Solving the Problems] The present invention provides an initial setting means for setting various initial values based on control data included in received data to be printed, and one line based on the set initial values. A print control unit for controlling the number of dots per hit is provided. The operation of the present invention having the above configuration will be described with reference to the flowchart of FIG. First, the initial setting means receives (refers to) character data to be printed, specifies the number of lines per unit length included in the character data, n lines / inch, and the dot density j dots / dot of the printer.
From inches, calculate the number of dots per line by j / n,
The integer part L and the fraction part l are registered. Further, an integer value m where m × (L + 1) is an integer (that is, a product of l is an integer) and a product k of m and l at that time are obtained, and these are registered [see]. This m is the number of lines where the cumulative value of the fraction l is an integer when the number of dots in one line is printed as L + 1 dots, and the value of m × l is the cumulative value of the fraction at that time. Many sets of m and k satisfying the above relationship can be obtained, but it is practical to obtain the minimum value among them. Next, the above-mentioned m rows are used as a control unit, and
Select a row [reference]. At the time of actual printing, the print control unit determines (refer to) whether or not the line corresponds to one of the selected k lines for each line, and if so, sets the line to L + 1 dots. If this is not the case, the line is set to L dots [see], and the printing control of this line is performed according to the set number of dots [see]. Check whether the above process has been completed for m lines,
If the number of rows has not been reached, the above processing is repeated [see]. Although not shown, this process is repeated for each control unit, with m rows of control units as one cycle. [Operation] As described above, when m lines are printed with L + 1 dots per line and m + 1 becomes an integer value k, when one line is printed with L dots, k dots are insufficient. I do. Therefore, if L + 1 dots increased by one dot are assigned to k rows of m rows, the shortage k
The dots will be corrected within m rows. That is, when printing is performed as described above, the number of dots in the entire m rows is (m−k) L + k (L + 1) = mL + k = m (L + 1). Matches the number. Therefore, the error due to the occurrence of a fraction is absorbed in m rows and does not accumulate. In addition, the displacement within the m-th row is extremely small, and is negligible. Hereinafter, an embodiment of the present invention will be described with reference to the drawings. FIG. 2 is a block diagram showing the configuration of an embodiment of the dot printer according to the present invention. In the figure, reference numeral 11 denotes a control unit in the claims, but a specific example of a CPU (Central Processing Unit), 12 denotes a receiving unit for receiving a data stream from the host computer 2, 13
Is a storage device and often uses RAM. 14 is a bitmap memory for developing patterns to be printed, 15
Denotes a printing unit. The RAM 13 is provided with a program area 20 and a work area 40. As will be described later, the program area 20 includes processing means for executing various processes of the present embodiment.
Is provided with a storage area used by each of the processing means. The bitmap memory 14 has a data development area 50 for developing figures and images and one character to be printed.
A character development line buffer 51 for developing a line pattern and a transfer line buffer 52 for storing one line of data to be transferred to the printing unit 15 are provided. Next, the operation of the dot printer configured as described above will be described with reference to the detailed configuration diagram of FIG. 3 and the flowchart of FIG.

[See Step # 1] First, the receiving unit 12 receives graphic or image data from the host computer 2 and stores it in the drawing data area 41.

[See Step # 2] The bitmap drawing unit 21 develops the data stored in the drawing data area 41 on the data development area 50.

[See Step # 3] Next, the receiving unit 12 receives character data from the host computer 2 and stores it in the character data area 42.

[See Step # 4] Based on the control data received simultaneously with the character data,
The initial setting unit 22 performs initial settings for print control. That is, the number of dots per line is calculated from the specified number of lines n per inch and the print dot density j, and the integer part L and the fraction part l are obtained. Next, the minimum value of m and k at which the product k of the fraction l and the integer value m becomes an integer value is obtained. As described above, when m lines are printed with L + 1 dots per line, the number m of lines such that the number of dots in the entire m lines becomes an integer value and the cumulative value of the fraction per line are calculated. L, l, m, and k obtained as described above are stored in the cycle area 46. In the present embodiment, control is performed with the above-mentioned m rows as one cycle during actual printing, and L + 1 dots are allocated to k rows of the m rows, and L dots are allocated to the remaining mk rows.
Therefore, an arbitrary k row is selected from the m rows, and the number of the selected row is indicated by a relative number from the head in the m rows,
This is stored in the selected row recording area 44. P ₁ , P ₁ ,
P ₂ , P ₃ ,... Indicate the selected line numbers. Actually, a recording area is provided for each row, and whether or not it is selected is identified by writing 1 or 0 in the recording area.

[See Step # 5] The cycle count area 43 is cleared. Thus, the initial setting is completed, and thereafter, printing control is performed according to the set value. Hereinafter, the operation of the print control will be described.

[See Step # 6] The line checking unit 23 refers to the selected line recording area 44 and checks whether or not the character line to be printed is the selected line.

[See Steps # 7 and # 8] In the case of the selected line, the number-of-dots setting unit 24 sets the size of the character expansion buffer 51 to L + 1 dots, and in the case of not the selected line, to L dots. Then, the set dot number is written in the dot number area 45.

[Refer to step # 9] The character developing unit 25 develops and edits the character data in the character developing line buffer 51 having the above-mentioned size, and copies it to the transfer line buffer 52.

[See Step # 10] The superimposing unit 26 cuts out the contents of the bitmap memory by the same number of dots as the size of the character expansion line buffer, and superimposes this on the transfer line buffer 52.

[See Step # 11] The print data output unit 27 reads the contents of the transfer line buffer 52,
It cuts out according to the number of pins of the printing unit 15 and outputs it to the printing unit 15. The printing unit 15 performs printing according to the received content.

[See Step # 12] The counting unit 28 increases the contents of the cycle count area 43 by one.

[Refer to Step # 13] The cycle check unit 29 performs the above-described cycle count area 43.
It is determined whether the cycle has ended based on whether or not the value has arrived at m. If not, the process returns to step 6 and repeats the above processing.

[Refer to step # 14] If the cycle has been completed, the data check unit 30 checks whether or not all the data has been completed. If not, the process returns to step 5 and repeats the above-mentioned control from the beginning of the cycle. . If there is no more data, the printing operation ends. In the above description, for example, if the print dot density j is 160 dots / inch and the number of lines per inch n is 6 lines / inch, the number of dots per line is 26.666. l becomes 0.666 (= 2/3). In this case, since m = 3 and k = 2, in this embodiment, three rows are defined as one cycle, and then 2 (= k) rows are converted to 27 (= L
+1) dots and the remaining 1 (= m−k) lines are printed with 26 (= L) dots. By controlling in this way, the position error due to the fraction is absorbed every 3 (= m) rows, and the error is not accumulated. In the embodiment described above, the initial setting unit 22 includes the initial setting unit of the present invention, the row check unit 23, and the dot number setting unit 2.
4, the character developing unit 25, the superimposing unit 26, the print data output unit 27, the count unit 28, the cycle check unit 29, and the data check unit 30 constitute a print control unit. In the above-described embodiment, an example in which a character, a figure, and an image are superimposed has been described. However, in the case of printing only a character, the configuration of the initial setting unit and the printing control unit, and the processing unit may be appropriately changed. The invention can be used. [Effects of the Invention] As described above, according to the present invention, the accumulated error that has conventionally occurred can be eliminated, and the relative displacement between the character and the contents of the bitmap memory can be suppressed within a maximum of 1 dot. Therefore, it is not necessary to perform operations such as thinning out the contents of the bit map memory, so that the received data can be faithfully printed and the printing quality can be improved.

[Brief description of the drawings]

FIG. 1 is a diagram illustrating the configuration of the present invention, FIG. 2 is a diagram illustrating the configuration of one embodiment of the present invention, FIG. 3 is a detailed configuration diagram of one embodiment of the present invention, and FIG. It is a flowchart which shows. In the figure, 1 is a dot printer, 15 is a printing unit, 20 is a program area, 21 is a bitmap drawing unit, 22 is an initial setting unit, 22 is a line check unit, 24 is a dot number setting unit, 25 is a character development unit, 26 is a superimposition section, 27 is a print data output section, 28 is a count section, 29 is a cycle check section, 30 is a data check section, 40 is a work area, 41 is a drawing data area, 42 is a character data area, and 43 is a cycle count. An area, 44 is a selected line recording area, 45 is a dot number area, 46 is a cycle area, 50 is a data development area, 51 is a character development row buffer, and 52 is a transfer row buffer.

Continuation of the front page (56) References JP-A-61-22973 (JP, A) JP-A-62-119075 (JP, A) JP-A-62-216777 (JP, A) JP-A-63-64782 (JP) JP-A-62-181169 (JP, A) JP-A-62-116177 (JP, A) JP-A-1-209150 (JP, A) (58) Fields investigated (Int. Cl. ⁶ , DB Name) B41J 19/76 B41J 2/515 B41J 2/51

Claims (1)

(57) [Claims] 1. A printing apparatus, comprising: a bitmap memory, a printing unit, and a control unit, wherein printing is performed by superimposing bitmap data including at least one of a figure and an image and character data, and performing printing. The bitmap memory includes at least a data development area for developing the bitmap data, and a transfer line buffer for storing one line of data to be transferred to the printing unit. Prints the data transferred from the transfer line buffer, the printing unit expands the bitmap data in the data expansion area, and evenly distributes character data printing lines in a printing scheduled area. In this case, the value L of the integer part and the value l of the fraction part are determined for the number of dots in the line feed direction per line of the character data printed line. , An integer m such that the product k with l is an integer, and the value of k are calculated, and k rows are selected from m consecutive rows to be printed.
A line is composed of (L + 1) dot character data in the line feed direction, the character data is expanded in the transfer line buffer, and the contents of the bitmap memory are cut out by the same number of dots in the line feed direction as the character data. The data is superimposed on the transfer line buffer, the data in the transfer line buffer is transferred to the printing unit, and a print instruction is issued. The remaining (mk) lines to be printed are represented by L dot character data in the line feed direction. The character data is expanded in the transfer line buffer, and the contents of the bitmap memory are cut out by the same number of dots in the line feed direction as the character data, and are superimposed on the transfer line buffer. A printing device for transferring data in a buffer to a printing unit and instructing printing.