JPS63249677A - Printing method for printer - Google Patents

Abstract

PURPOSE:To enhance the accuracy of positioning for printing, by printing in the same direction as that in the preceding printing when a line feed (LF) code is present in continuation to a carriage return (CR) code. CONSTITUTION:When a CR code appears in printing data, it is checked whether an LF code is present precedingly or in continuation to the CR code. When the LF code is present, line feeding by a one-line amount is carried out under predetermined conditions, and rightward or leftward printing in one line is performed. When the LF code is not present precedingly or in continuation to the CR code, printing data for the next one line is printed in the same line and in the same direction as that in the preceding printing operation. Therefore, the accuracy of positioning between the preceding printing and the subsequent printing is made extremely favorable.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Use] The present invention relates to a printing method for a printer used as a printing device for a computer or the like.

[Prior Art] A printer used as a printing device for a computer, etc. receives print data output from a computer, etc., and performs a printing operation according to the data, but this data includes a character code representing the character to be printed. In addition, it also includes control codes that control the printing operations of the printer. These control codes include a carriage return (CR) code and a line feed (LF) code, and when the printer receives these codes, it executes a printing operation to print the character data received so far on one line. Among these, in the case of a CR code, after performing the above printing operation, move the printing position to a predetermined left margin position without performing line feed, and print character data starting from that CR code on the same line to the left. Enable printing from the margin position. Also, in the case of LP code,
The vertical printing position is moved by one line without changing the horizontal position.

Normally, computers send pairs of CR code and LF code to the printer at the point where a line break is to be made in a document.
Although a line feed operation is executed, when overprinting characters such as emphasized printing or underlining, a method of sending only the CR code to the printer may be used.

On the other hand, on the printer side, in order to improve the printing speed, printers that print in both left and right directions have been devised (for example,
U.S. Patent Publication No. 3.764.994).

After printing a certain line, the next line's printing start position is determined from the printing end position (in this case, the printing start position of the line is not necessarily at the left end, but if the right end is closer, printing starts from the right end). The carriage carrying the print head is moved in the direction that minimizes the distance to the print head (the space at the end of the line is ignored). In such a printer, line printing may be performed from either the left or right direction.

[Problems to be Solved by the Invention] When using a printer that uses a bidirectional printing method to overprint characters at the same line position using a CR code, the print end position of the previous print line and the print of the next print line are In relation to the start position, the printing directions of both print lines printed at the same print line position may be reversed. In such cases, due to backlash in the carriage positioning mechanism and differences in vibration modes when the carriage stops, even if you try to print the same character over and over, the print position will change slightly for each character, resulting in printing problems. The disadvantage is that the quality deteriorates.

[Means for solving the problem] The present invention, which was made to solve the above problem, has a carriage return code in print data, as shown in Figure 1. When it appears (Sl) under predetermined conditions (S3) Printing one line in either the left or right direction (S4.95) The printer prints a line feed continuously to the carriage return code immediately after the previously printed data. If the code does not exist (S2), the printer performs a printing operation in the same direction as the previous printing operation (S6).

[Operation] When print data is sent from a cocomputer or the like, the printer sequentially stores the print data in its own internal buffer (memory).

Then, there is a carriage return (CR) in the print data.
When the code is found (Sl), one line is printed on paper or the like based on the print data stored in the buffer up to that point. In addition to character data, these print data also include print control codes for special printing such as superscripts and subscripts.

In this way, this printer prints one line at a time, but when a CR code appears, in order to improve the printing speed, predetermined conditions, such as the horizontal position of the last printed line and the next Printing of the next print line is started under conditions that minimize the carriage movement distance in relation to the print start horizontal position of the print line to be printed (S3).
. Therefore, line printing may be performed both to the right and to the left (S4, S5).

In the present invention, when a CR code appears in print data (
Line feed (LF) continuously before and after SL)
It is checked whether the code exists (S2). LF
If the code exists, one line of print data to the right or to the left is printed according to the predetermined conditions as described above for the print data after the print data printed last time (S4
, S5).

In this case, since there is an LF code, the next line is printed after a predetermined one-line feed from the previous print line.

On the other hand, if there are no LF codes consecutively before and after the CR code, line feed from the previous printed line is not performed,
The next line of print data is printed on the same line.

At this time, the printing direction is made the same as the previous printing line without making the above-mentioned conditional judgment regarding the printing direction (S3).
S6).

Therefore, backlash in the carriage moving mechanism can be eliminated, and the vibration mode when the carriage stops is also the same as the previous one, resulting in extremely high positioning accuracy between the previous printing and the next printing.

[Example] Embodiments of the present invention will be described below with reference to the drawings.

In this embodiment, a daisy-wheel printer that performs bidirectional printing is provided with a printing program that incorporates the printing method according to the present invention.

FIG. 2 is a diagram showing the configuration of the printer 1 of this embodiment. The printer 1 is roughly divided into a mechanism section 10 and an electronic control section 100. The mechanism part 10 is
It is constructed mainly of a platen 20 fixed to a frame 12 and a carriage 52 that is movable left and right on a guide shaft 50 fixed to the frame 12 parallel to the platen 20.

A printing paper 22 is wound around the platen 20, and a line feed stepping motor 24 and a gear mechanism 26 for rotating the platen 20 are provided to feed the printing paper in the vertical direction.

The carriage 52 includes a print head 58 consisting of a daisy wheel 54 and a print hammer 56, and a print ribbon 6.
A ribbon cassette 62 for storing 0 inside, a lifting mechanism for lifting the printing ribbon 60 to a printing position during a printing operation, a mechanism for winding the printing ribbon 60, and the like are installed. The carriage 52 itself is connected to the guide shaft 50 by a carriage stepping motor 64, left and right pulleys 66, 68, and a belt 70.
move above.

The electronic control unit 100 includes CPUIO1ROM120, RA
M130, and in addition to these, a print control circuit 140 connected to the print head and ribbon lifting/winding mechanism, a line feed stepping motor 24, and a carriage stepping motor 6.
4, an input/output circuit 160 for connecting to an external computer 200, etc., and a pass line 180 for connecting each of these elements and circuits. The CPU 110 receives print data from an external computer 200, etc. according to various programs stored in advance in the ROM 120 for controlling the printer 1, and prints data from the print head 56, carriage 52, and platen 20.
etc. are controlled via control circuits 140, 150, etc. to print characters. In addition to the control program described above, the ROM 120 stores constants for initializing the printer 1, tables referenced during control, and the like. RAM130 has 1
A line buffer (L) that stores print data for a line
B) area, print head 5 The printer 1 includes an area for temporarily storing data during control of the printer 1, such as a printing direction storage area for storing the printing direction of the 5th day.

The printing operation of this printer 1 will be explained below based on the flowchart shown in FIG. In the following description, it is assumed for simplicity that each character data consists of one byte.

When the routine shown in the flowchart of FIG. 3 is started, first, in step 301, the external computer 200
From there, one byte of print data is manually input via the input/output circuit 160. In step 302, it is determined whether this manual data is a carriage return (CR) code. In ASCII code, the CR code is O
DH (H represents hexadecimal notation). If the manual data is not a CR code, the data is sequentially stored in the line buffer (LB) in the RAM 130 in step 303, and the process returns to step 301 to perform the next 1-byte manual data.

If it is determined in step 302 that the input data is a CR code, the process moves to step 304 and the next 1 byte is input. Then, in step 305, it is determined whether the data is a line feed (LF) code. In ASCII code, the LF code is OAH. If it is determined that this additionally inputted data is an LF code, the process proceeds to step 306, and the previous position P1 and final position P2 of character data that is not a space code in the data stored in the line buffer are detected. do. Then, in step 307, the current print head position PO is read from the RAM 130, and in step 308, this position PO is
It is determined which of the two is closer. If it is determined that PO is closer to Pl, then in step 309 the print data in the line buffer is printed in the right direction, that is, one line is printed from left to right. If the determination result in step 308 is the opposite, leftward printing is executed in step 310.

In addition to character codes, the print data in the line buffer also includes control codes for superscripts and subscripts. perform an action. In addition, if the control code includes a special code for emphasized printing, for example, an ASCII code defined as IBH/21H, the CPU 110 controls the carriage 52 according to the emphasized printing control program stored in the ROM 120.
A special positioning control is performed, and the character data between them is typed twice until an emphasis printing cancellation code, for example, IBH/22H, etc. appears. Note that in the printer 1 of the present invention, such a function is not necessarily necessary.

After one line of printing is executed in step 309 or 310, in step 311, the printing direction D (right or left) is
is stored in the RAM 130.

Finally, in step 312, a predetermined value is set to the line feed stepping motor 24 via the print position control circuit 150.
A drive signal is output to advance the line by a line. As a result, the platen 20 rotates by a predetermined amount, and the printing paper 22 is fed by one line. After clearing the data in the line buffer, the process returns to step 301 and the next byte is manually written.

If it is determined in step 305 that the additional input data is not an LF code, the process moves to step 313, where the additional input data is stored at the beginning of the next line buffer (NLB) prepared in RAM 130 for the next print line. The contents of this NLB are 1 of the line buffer as described later.
After a line has been printed, it is transferred to the line buffer.

Next, in step 314, the data immediately before the first manually generated CR code is read from the line bar sofa, and in step 315, it is determined whether the data is an LF code. If this data is an LF code, the process moves to steps 306 to 312 and prints one line of print data in the line buffer on the next line in either the left or right direction. do.

If it is determined in step 315 that the data immediately before the CR code is not an LF code, the process advances to step 316 and the RA
The previous printing direction stored in M130 is read, and in step 317, the line bar is printed in the same direction as the D direction.
Executes printing of the print data inside the sofa. Note that at this time, since the line feed corresponding to step 306 is not performed, printing is performed on the same line as the previous print line. After printing is completed, the data in the line buffer is cleared, and in step 318 the NLB data is transferred to the line buffer as described above, and the process returns to step 301.

In this embodiment, as described above, when an LF code exists before and after a CR code, normal bidirectional printing is performed.
If no LF code exists before or after the R code, the printing operation is performed in the same direction as the previous printing direction. Therefore, when printing special characters by overprinting the same character or overprinting different types of characters, by including a CR code without an LF code in the print data sent to the printer 1, it is possible to Accurate and beautiful overprint printing can be performed without requiring carriage positioning accuracy.

The present invention is not limited to this, but includes various embodiments without departing from the gist thereof.

1 for 5 sides As detailed above, in the present invention, even in a printer that performs bidirectional printing, if a line feed (LF) code exists consecutively to a carriage return (CR) code, the code is the same as the previous one. Since printing is performed in the printing direction, for example, even when emphasizing printing by overprinting the same character by interposing only the CR code, the positioning accuracy of the character printing position is extremely good. Furthermore, another feature of the present invention is that such effects can be obtained using the conventional mechanism without increasing the rigidity of the mechanical system in order to improve the carriage positioning accuracy.

[Brief explanation of the drawing]

FIG. 1 is a flowchart illustrating the outline of the present invention;
The figure is a schematic configuration diagram of a printer that is an embodiment of the present invention.
The figure is a flowchart showing the flow of processing performed by the electronic control section of the printer of this embodiment. 1... Printer, 10... Mechanism part 12... Frame, 20...
Platen, 24... Stepping motor for line feed 52... Carriage, 58.
... Print head, 64 ... Carriage stepping motor 100 ... Electronic control section

Claims (1)

[Claims] 1 When a carriage return code appears in the print data, in a printer that prints one line in either the left or right direction under certain conditions, a line feed code will appear immediately after the carriage return code immediately after the previously printed data. A printing method for a printer characterized in that, if the printer does not exist, the printing operation is performed in the same direction as the previous printing operation.