JPH0463786B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (a) Field of Industrial Application The present invention relates to a printing method that performs tab set control so that a printer can print with the heads aligned for each column.

(b) Prior art When tabulating data on a typewriter, a method called tabset is often used. A tab set is a tab (TAB) for each desired column (digit).
If you set a value and press the "Tab" key during tabulation, the carriage will automatically skip to the column you have set, so if you print at that set position, the printing will be aligned for each column and the printing will be done. A table is created. If such a tab set operation is not performed, it is very troublesome to have to press the space key as many times as necessary to move to the next column after printing in each column is completed.

Recently, it has been considered to introduce such a tab set method to printers, but it is possible to print by changing the character spacing (for example, 10 cpi and 12 cpi) or by changing the character spacing depending on the width of the character. In the case of proportional spacing printing, there is a problem in the conventional printing method in which tabs are set based on the number of characters, that the heads of each column are not aligned in a straight line, resulting in poor visibility of the tabulation.

(c) Object and structure of the invention The present invention has been made in view of the above points, and an object of the present invention is to ensure that the heads of each column are aligned when tab setting is performed in a printing method using a dot printer, and for this purpose, the tab set is The position is specified by the number of dots, and tab set control is performed based on the total number of printed dots and the number of dots specifying the tab set position.

(d) Examples The present invention will be explained below based on the drawings.

FIG. 1 is a functional block diagram of the main parts of a printer that implements the tab set control printing method according to the present invention, and the tab set control method will be explained using this diagram.

Coded (for example, hexadecimal) character information and control commands for printing are transmitted from the host device to the printer. This control command includes a tab set command. Character information and control commands are temporarily stored in the input buffer 1. The character information and control commands stored in the input buffer 1 are each decoded by a central processing unit (not shown) and stored in the page memory 2, but in this case, the character information has the MSB (most significant bit) as " 0”
As character data expressed in 1 byte,
Further, the control command is stored as control data represented by 1 byte with the MSB set to "1". Figure 2 A shows, for example, the letter “A” for Alphabetical16.
Character data with a hexadecimal character code "41" is shown as an example, and control data with a code "09" representing "HT (horizontal tab)" is shown in FIG. The code for each character etc. is determined in advance.

Tab set table 3 contains preset standard column tab set values (for example, 1, 180, 360, 540,
720), and when a tab set command is transmitted from the host device as described later, the standard tab set value is replaced with the tab set value specified by the tab set command.

The ROM of the horizontal dot table 4 contains the number of horizontal dots, which is one of the attribute information of each character (for example, the number of horizontal dots for alphabets "A", "B", and "C" are 26, 28, and 27, respectively). It is stored as a table.

The character data stored in the page memory 2 is converted by a data converter 5 into the start address data of the corresponding character memory so that the dot data output from the character generator 8 can be easily read out, and is stored column by column in the character line buffer 6. do. On the other hand, the number of horizontal dots of a character, which is one of the attribute data of each character stored in the character line buffer 6, is read out from the horizontal dot table 4 and written into the attribute line buffer 7. Other attribute line buffer 7 includes
Data that commands underlining, character reversal (black and white), and character size is written.

After one line of character data and attribute data are written in the character line buffer 6 and attribute line buffer 7 in this way, both line buffers 6 and 7 are data is read.
The character data in the first column read from the character line buffer 6 is the start address of the corresponding character generated from the character generator 8, so that the character generator 8 outputs the dot data of the corresponding character. It is sent to the parallel-to-serial conversion circuit 9. On the other hand, the number of horizontal dots of the character corresponding to the column of the character line buffer 6 is read out from the attribute line buffer 7 and counted by the dot counter 10.

The character dot data in the parallel-to-serial conversion circuit 9 is read out in synchronization with the dot clock CLK for printing in the printing section 13, and is sent to the printing section 13 as a video signal.
sent to. The dot clock CLK serves as a trigger clock for the parallel-to-serial conversion circuit 9, and is also input to the H counter 11 and counted.

The count value of the H counter 11 is compared with the count value of the dot counter 10 by the comparison circuit 12, and when the two match (this means that horizontal dots for one character have been read), the comparison circuit 12 compares the count value of the H counter 11 with the count value of the dot counter 10. A character end signal CE is outputted from and sent to the line buffer counter 14. When the character end signal CE is input to the line buffer counter 14 and the count value increases by 1, the address of the character and attribute line buffers 6 and 7 is advanced by one column, and the start address data of the character in the second column is read out. make it possible to do so.

In this way, a video signal is generated based on the character information and control commands transmitted from the host device.

Next, the tab set operation according to the present invention will be explained.

When the tabset values that define the columns at the time of tabulation differ from the predetermined standard tabset values, the tabset values to be set are transmitted from the host device to the printer side as a tabset command prior to the printing operation. For example, when the tab set value transmitted from the host device is specified as 240, 480, or 720, the standard tab set value preset in the tab set table 3 of the printer is replaced with the specified tab set value. After that, the printing operation starts, and the character data is “A”, “B”, etc.
“C”, “HT”, “D”, “E”, “HT”, “F”, “
C/
If "R (carriage return)" and "L/F (line feed)" are transmitted, the characters "A", "B", and "C" stored in the horizontal dot table 4 are
Since the number of horizontal dots is 26, 28, and 27, respectively,
The count value of the dot counter 10 when reading out "A", "B", and "C" is 81. Next, “HT”
When reading the first tab from tab set table 3,
The tab set value 240 is read out, and the content of the dot counter 10 (count value 81) is reset to 240. As a result, after the dot data of "A", "B", and "C" are read out from the video signal, the H counter 11 generates a character end signal CE from the comparison circuit 12 until the counted value reaches 240. Instead, the parallel-to-serial conversion circuit 9 outputs empty dot data as a video signal.

Thereafter, when the count value of the H counter 11 reaches 240, a character end signal is generated from the comparison circuit 12, the line buffer counter 14 is advanced by one column, and the first character "D" of the next column (second column) is generated. The start address of is read from the character line buffer 6.

When printing (“D”, “E”) in the second column is completed, empty dot data is output in the same way until the count value of the H counter 11 reaches the next tab set value of 480, and when it reaches 480. When the character end signal is generated, the line buffer counter 14 is further advanced by one column, and the start address of the first character "F" in the next column (third column) is read out from the character line buffer 6, and the character generator Sent to 8th.

Thereafter, each row is printed in exactly the same way, so that the beginning of each column, that is, the start of printing, is aligned in a straight line, resulting in a tabulation that looks good.

(e) Effects of the Invention As explained above, in the present invention, the tab set value is specified by the number of dots instead of the number of characters, so the heads of each column are aligned in a straight line, making it possible to print with good visibility. , tables etc. can be created neatly.

The present invention is particularly effective when performing proportional or spacing printing, but is also effective when printing with varying character spacing in normal printing.

[Brief explanation of drawings]

FIG. 1 is a functional block diagram of the main parts of a printer that performs printing using the tab set control method according to the present invention.
FIG. 2 shows an example of data for printing, where A is character data and B is tab set control data. 1...Input buffer, 2...Page memory, 3...
Tab set table, 4...Horizontal dot table,
6...Character line buffer, 7...Attribute line buffer, 8...Character generator, 9...Parallel/serial conversion circuit, 10...Dot counter, 11...H counter, 12...Comparison circuit, 13...Printing section , 14...
...Line buffer counter.

Claims (1)

[Claims] 1. In a printing method that prints with a different number of dots determined for each character, the tab set position is specified by the number of dots, the print data string containing the character code and tab code supplied from the host device is stored, and the stored print When sequentially reading and printing a data string, the number of dots in the printing direction is counted in the process of printing one line, and when the tab code is read, the number of dots in the printing direction is counted. A tab set control printing method characterized in that the next character is printed after outputting blank dot data until the value reaches the number of dots at the specified tab set position.