JPH0457510B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field] The present invention relates to a high-quality printing method for a dot printer that prints characters, symbols, etc. using a collection of dots.

[Prior art]

Below, the high-quality printing method of a conventional dot printer will be explained based on the dot pattern shown in the figure, and its drawbacks will also be discussed.

1A shows a conventional basic dot pattern, FIGS. 1B and 2C show a high print quality pattern, FIGS. 2A and 2B show two different printing patterns, and FIG. 2C shows a high print quality pattern. The number 4 is used as one column.

The first method is to increase the number of wires in the print head and arrange them in a staggered pattern to create a high-density dot configuration, but this method provides high print quality but has the disadvantage that the device configuration and control are complicated. This also has the disadvantage of making the device expensive.

The second method is to print the basic pattern shown in Figure 1a by slightly shifting it in the horizontal direction as shown in Figure 1b, and to print the basic pattern slightly in the vertical direction as shown in Figure 1c. There is a method in which printing is performed by shifting the image, but this method is simple and the device is inexpensive, but it has the disadvantage of poor printing quality.

The third method is to slightly shift two different patterns in the vertical direction, such as the pattern shown in Figure 2a and the pattern shown in Figure 2B, to obtain high-quality printing as shown in Figure 2C. However, this method has the disadvantage that the character pattern is stored separately, which increases the memory capacity and makes it expensive.

[Purpose of the invention]

SUMMARY OF THE INVENTION Accordingly, the present invention aims to solve the conventional drawbacks by providing a high-quality printing method using an inexpensive dot printer with a small memory capacity for character pattern generation.

[Structure of the invention]

The present invention generates a first dot matrix pattern by interpolating the horizontal direction of the basic dot matrix pattern from the basic dot matrix pattern using an algorithm, and synthesizes and edits the first dot matrix pattern and the basic dot matrix pattern. The dot matrix pattern is printed in the first pass of the print head, and the print head and printing paper are 1/2 of the basic dot matrix pattern.
After relatively moving in the vertical direction by the dot printing interval, a second dot matrix pattern is generated from the basic dot matrix pattern by interpolating the vertical and diagonal directions of the basic dot matrix pattern, and this second dot matrix pattern is In a dot printer printing method in which a matrix pattern is printed in the second pass of the print head, the second dot matrix pattern is printed on the mth row (n-1) and column (n+1) of the basic dot matrix pattern. There is each dot (m, n are integers),
And if there is a dot in the n column of the (m+1)th row,
A dot is interpolated at the n-th column position between rows m and (m+1), and if there is a dot at the n-th column of the m-th row of the basic dot matrix pattern and there is a dot at the (m+1)-th row ( If there are dots in columns n-1) and (n1), high-quality printing is possible, including a dot pattern that interpolates the dots at the n-th position between rows m and (m+1). can be obtained.

〔Example〕

An embodiment of the present invention will be described below based on the drawings, and its effects will be described.

FIG. 3 is a block diagram showing a schematic configuration of an apparatus according to an embodiment of the present invention, in which 1 is a microprocessor (hereinafter referred to as CPU) that controls the printer;
3 is a read-only memory (hereinafter referred to as ROMa) that stores programs, 3 is a read-only memory (hereinafter referred to as ROMb) that stores dot patterns such as characters and symbols, and 4 is a read-only memory (hereinafter referred to as ROMb) that stores programs. A driving I/O driver 5 is a print head 5 connected to the I/O driver 4,
Driver 4 also includes a printer for printing paper line breaks (not shown).
The LF motor is connected to the SP motor for spacing that moves the print head in the printing direction, and the interface unit that takes in print data from the outside. 6 is a bus line connecting each component.

In printing by a device having such a circuit configuration, the CPU 1 first receives control data and print data (character code) from the interface according to the program stored in the ROMa 2. When the print data is received, use it as an address.
Read the character dot pattern from ROMb3. Here, if the control data specifies high-quality printing, the character dot pattern read from ROMb3 is edited by a conversion algorithm, and printing is performed based on the edited data.

Next, a conversion algorithm for achieving high print quality will be described based on FIG. 4.

Figure 4 a to h show the conversion of various basic patterns by the algorithm.
The dot data read from ROMb3 indicates that there is no dot data read from ROMb3 on that grid, and the dot data to be interpolated.

Next, an example of printing by the above conversion algorithm using the number 4 as an example is shown in FIGS. 5 and 6.

Figure 5 shows the basic pattern, and the pattern is
Read from ROMb3. Here, the character pattern is composed of seven vertical rows (r ¹ to r ⁷ ) and nine horizontal columns (c ¹ to ^{c 9} ).

Figure 6 shows the basic pattern shown in Figure 5 and the 4th pattern above.
This is a print pattern obtained by printing a second pattern edited using the conversion algorithm shown in the figure. As shown in the figure, a ¹ to a ⁴ are interpolated dots obtained by the conversion shown in FIG. 4 a, b ¹ to b ⁴ are interpolated dots obtained by the conversion shown in FIG. 4 b,
e ¹ to ^{e 3} are interpolated dots obtained by the conversion shown in FIG. 4e, and h ¹ is an interpolated dot obtained by the conversion shown in FIG. 4 h.

This number 4 is printed on head 5 in Figure 3 above.
will do it. The head 5 consists of seven wires,
First, in the first spacing (1 pass), after printing the dots on rows ^r1 to ^r7 shown in Figure 6, either line feed the printing paper by 1/2 dot upwards or move the print head 5 downwards. The dots are lowered by 1/2 dot and the dots on r ¹ ' to ^{r 6} ' shown in FIG. 6 are printed in the second spacing to achieve high quality printing as shown in the same figure.
Printing that fills in the gaps in this basic pattern is performed based on interpolated data by a conversion algorithm.

Next, generation of this interpolation data and printing operation will be explained based on FIGS. 7 and 8.

FIG. 7 is a flowchart of conversion processing for integer columns, and FIG. 8 is a flowchart of conversion processing for cases other than integer columns.

In the figure, c ¹ to ^{c 9} shown in Figure 6 above are integer columns, and Rn, Rn ^-1 , and Rn ₊₁ are the print data of the column to be printed respectively when they are integer columns, and the print data of the previous column. , is a register that stores print data for the next column. However, for columns other than integer columns (columns ^C1 ' to ^C8 ' shown in Figure 6), the print data of the column 1/4 dot after the column to be printed, the print data of the column 1/4 dot before the column to be printed,
Stores the print data of the column after 3/4 dots. Ra~Rd and Rx~Rz are general-purpose registers, respectively.
Rx is a register that stores print data 1/4 dot before, and A is an accumulator. Indicating each operation, / indicates logical product, + indicates logical sum, ×2 indicates 1-bit shift up, ×1/2 indicates 1-bit shift down, -
represents complement. ~ is the number of each step.

Here, we will begin to explain the printing operation, as shown in Figures 3 and 4.
The explanation will be continued with reference to FIGS. 5, 5, and 6 as necessary.

Its operation is driven by the SP motor shown in Figure 3.
The print head 5 moves to a predetermined position, and the character code to be printed is given to the CPU 1 from the interface via the I/O driver 4.

CPU1 reads the print data of the column to be printed and the next column from ROMb3 using the above character code and column number as an address and registers it.
Store in Rn, Rn ₊₁ . At this time, 0 is stored in register Rn _-1 .

After this storage, the conversion process shown in FIG. 7 begins. First, it is determined whether the step is the first pass.
If it is the first pass, step processing is performed and the interpolation shown in FIG. 4b is performed.

In this step, the next print data is read from ROMb3 and stored in register Rn ₊₁ .

Printing is performed from this state. This is done by supplying the data from the accumulator A to the print head 5, and when the printing of one integer column is completed, the process moves to the next integer column, and so on, repeating the process of step 3 to finish one character. , which is the row r ¹ illustrated in Figure 6 above.
~r ⁷ will be printed above. In this manner, when printing of one character is completed, the CPU 1 receives the next code and performs the same process as described above, thereby printing one line. This is a state in which all rows r ¹ to ^{r 7} illustrated in FIG. 6 have been printed over one line.

After printing one line of rows r ¹ to ^{r 7} in this way, move the printing paper upwards with a 1/2 dot line feed or move the print head 5 downwards with a 1/2 dot line feed, and then 5 is returned to the first character printing position in that line and printing begins for the second pass.

First, as above, print data is stored in registers Rn, Rn _-1 , and Rn ₊₁ , and conversion processing begins.

Since this is the second pass in the step, we will proceed to the step here. The step determines whether it is an integer column or a non-integer column, and if it is an integer column, the step is entered.

The step is to create the interpolated data shown in Figure 4 a, the step is to create the interpolated data shown in Figures 4 c and d, and the step is executed only when there is no data in the bits shown in Figure 4 c and d. Effectively process interpolated data, steps are shown in Figure 4g.
Processing to interpolate and h (processing to interpolate a dot at the midpoint when three dots form a triangle), the step is editing processing, and the row printed 1/4 dot before is I'm trying not to print it. A step is a preparation process for the next column.

Note that the interpolation process in the above steps is performed when there are dots in the m-th row (n-1) column and (n+1) column of the basic dot matrix pattern (m and n are integers), and the (m+1)-th row If there is a dot in column n, interpolate the dot at the position between rows m and (m+1) and in the nth column (interpolation shown in Figure 4g),
In addition, if there is a dot in the mth row and n column of the basic dot matrix pattern, and there are dots in the (m+1)th row, the (n-1) column and the (n+1) column, then the mth row and (m+1) Interpolate a dot in the middle of the row and at the nth column position (interpolation shown in Figure 4h)
It is something.

The above process not only interpolates between dots in the vertical, horizontal, and diagonal directions, but also interpolates dots at intermediate positions between the three dots located on the vertices of such triangles, thereby creating line segments in different directions. The outline of the printed characters at the intersection can be made to appear to have an appropriate thickness without being thin or thick.

For example, using the example in Figure 6, a pattern with dots at the intersection of row r ⁴ and column c ² , and at the two intersections of row r ⁵ and columns c ¹ and c ³ is the conversion example shown in Figure 4 h. ^{Corresponding to}
By simply interpolating h ¹ , the outline of the print in this area can be made to appear appropriately thick. If the above dot
If h ¹ were not interpolated, the outline of the print in this area would appear thin, whereas if two dots were interpolated at the intersection of row r ⁴ ′ and columns c ¹ ′ and c ³ ′, The outline of the printed character on the cigarette will appear thicker or crushed than the surrounding area, and in either case, variations in the thickness of the line segments that make up the printed character will occur, reducing the quality of the printed character. I will let you do it.

The above is the processing for the integer column shown in FIG. 7, and the conversion processing for cases other than the integer column shown in FIG. 8 is added to this.

The step in Fig. 8 is a process for creating interpolated data in e and f in Fig. 4, and the step makes the interpolated data in the step valid only when there is no data in the bits shown in Fig. 4 e and f. The processing and steps are editing processing similar to the steps shown in FIG. 7 above, and the steps are also preparation processing similar to the steps shown in FIG.

This second pass printing is performed by applying the data of the accumulator A obtained in the editing process and step described above to the print head 5.

Based on this, when the printing of one column is completed, the process moves to the next column and repeats the process from the step onwards, and the printing of one character is completed. This is the 6th above
The rows r ¹ ′ to r ⁶ ′ illustrated in the figure are printed. In this manner, when the printing of one character is completed, the CPU 1 receives a new character code of the next character and repeats the above-described process, thus completing the printing of one line. This is the result of the row r ¹ ′~ shown in Figure 6.
The entire line for r ⁶ ′ is printed,
The printing of the algorithm conversion process for that line, that is, the high-quality printing ends.

Thereafter, a line feed for one line is performed, and the print head 5 is returned to the printing start position, and printing of the next line begins.

Incidentally, in the above embodiment, the conversion process is performed at a slow printing speed of the printer, but if the printing speed of the printer is fast, a buffer memory is connected to the bus line 6 in FIG. 3 and editing processing is performed before the printing operation. If print data is stored in the buffer memory and the print data is read out from the buffer memory and printed at the time of printing, high-speed printing with the same effect can be achieved.

The conversion process in this case is to distinguish between the editing results of the step in FIG. 7 and the editing results of the steps and steps in FIGS. 7 and 8, and to store them in the buffer memory. Sometimes, it is sufficient to read the first pass print data and the second pass print data from distinct areas of the buffer memory.

In addition, although the present embodiment has been described using a dot matrix of 7 vertical by 9 horizontal, the present invention is not limited to this, and the present invention can be implemented on a basic dot matrix of any dot matrix configuration.
A dot pattern with high print quality can be obtained with a small memory capacity.

For example, the number of characters used in normal printers is approximately 256 alphabets, numbers, symbols, and kana characters, and if the printer has a dot pattern for high print quality, each character is There are 2 patterns, and if it is configured with 9 columns, 256 x 2 x 9 =
4608 bytes of memory is required. According to the present invention, this can be made into a conversion program of about 200 bytes.

It goes without saying that the present invention can be used not only for printers but also for display devices and the like. Furthermore, the present invention can be applied to printers that have a function of registering character dot patterns from an external device into the printer's random access memory (RAM) from the registered basic patterns, and can print character patterns with high print quality. be able to.

〔Effect of the invention〕

According to the present invention described in detail above, an algorithm is used to interpolate dots not only in the vertical, horizontal, and diagonal directions but also at the midpoint position when dots are arranged at each vertex of a triangle using an algorithm based on the basic dot matrix pattern. Since a custom dot pattern is generated and printed, there is an effect that high quality and highly clear printing can be obtained, and the dot printer to which the present invention is applied can also exhibit the following effects.

Compared to the conventional method of increasing the number of wires in the head, this has a simpler device configuration and has the effect of providing an inexpensive device.

Moreover, compared to the conventional method of printing the same pattern twice with a slight shift, high print quality is ensured and there is an effect of improving high print quality.

Moreover, compared to the conventional method of printing different patterns slightly shifted from each other, this method has the effect of drastically reducing memory capacity.

As described above, the present invention, which can provide a simple and inexpensive dot printer with high print quality, can be used not only for dot printers but also for printers that perform high print quality from registered basic patterns, and can also be used for display devices.

[Brief explanation of the drawing]

Figure 1a is a conventional basic dot pattern, Figures b and c are conventional high print quality patterns, Figure 2a,
b shows two different conventional printing patterns, and c shows the same figure.
3 is a block diagram showing a schematic configuration of a device according to an embodiment of the present invention, FIGS. 4 a to h are conversion processing diagrams using algorithms for various basic patterns, and FIG. 5 is a basic pattern. Pattern diagram, Figure 6 is an algorithm conversion process diagram, Figure 7 is a flowchart of conversion process for integer columns,
FIG. 8 is a flowchart of conversion processing for cases other than integer columns. 1...CPU, 2...ROMa, 3...ROMb, 4...
I/O driver, 5...print head, 6...bus line.

Claims (1)

[Claims] 1. Generate a first dot matrix pattern that interpolates the basic dot matrix pattern in the horizontal direction using an algorithm from the basic dot matrix pattern, and combine the first dot matrix pattern with the basic dot matrix pattern. The synthesized and edited dot matrix pattern is printed in the first pass of the print head, and the print head and printing paper are moved relative to each other in the vertical direction by 1/2 dot printing interval of the basic dot matrix pattern, and then the basic dot matrix pattern is printed. A dot printer printing method in which a second dot matrix pattern is generated from the matrix pattern by interpolating the basic dot matrix pattern in the vertical and diagonal directions using an algorithm, and this second dot matrix pattern is printed in the second pass of the print head. In the above, the second dot matrix pattern is the mth row (n-) of the basic dot matrix pattern.
1) There are dots in columns (m, n) and (n+1).
is an integer), and if there is a dot in the (m+1)th row and the n column, then the dot is between the m and (m+1) rows and the n
Interpolate dots at the column positions, and then add m of the basic dot matrix pattern.
If there is a dot in the nth column of the row, and there are dots in the (n-1)th column and the (n+1)th column of the (m+1)th row, 1. A dot printer printing method comprising a dot pattern for interpolating dots at positions.