JPS62146644A - Serial dot printer - Google Patents

Abstract

PURPOSE:To make the mounting of the printing head of a different dot pitch possible, by a method wherein the dot pitch of a printing head is detected and printing control parameters such as a printing data buffer size, a dot line number, a carrier travelling velocity, etc. are altered. CONSTITUTION:The printing data and the control code from a higher order apparatus 24 are received at an input processor 18 and the printing data is developed in a printing head drive pattern via a character generator 19 to be stored in a line buffer 4. When the control code becoming an initializer for printing is received, or otherwise the filling of an entire line buffer is detected, a motor control 22 and a printing head control 23 are started by adding the printing start position, an end position, and a line feed data for executing printing. Thereby, the printing head control 23 successively takes out the data of the line buffer 4 synchronizing with the rotation of a carrier motor 13 and outputs it to a printing head 12. A printing control 20 waits until the printing is accomplished and when completed, it starts the input processor 18 up again. By the repetition of above-mentioned operation, the printing is continued.

Description

[Detailed Description of the Invention] [Field of Application of the Invention] The present invention relates to a so-called serial dot printer (hereinafter simply referred to as a "printer") that performs line-by-line printing using a print head. It is related to printers.

[Background of the invention]

Conventionally, by using one print head and changing the carrier speed and print head drive timing,
A printer that changes the dot pitch in the horizontal direction (print head movement direction) to create an arbitrary dot pitch and prints enlarged or reduced printing is disclosed in, for example, Japanese Patent Laid-Open No. 58-6'206.
This is well known as disclosed in Publication No. 8 and the like.

However, there has been no known technique for creating an arbitrary dot pitch by changing the dot pitch in a direction perpendicular to this, that is, in the vertical direction (direction perpendicular to the print head movement direction). This is because the vertical dot pitch is essentially determined by the physical dimensions of the print head and cannot be controlled. There was a serious problem that it was not possible.

[Purpose of the invention]

An object of the present invention is to provide a printer that eliminates the above-mentioned problems with conventional printers, makes it possible to use a plurality of print heads with different dot pitches, and allows the aspect ratio to be freely selected. .

[Summary of the invention]

The above-mentioned object of the present invention is to provide a means for detecting the dot pitch of the print head in a printer that prints line by line using the print head, and to detect the print data buffer size, the number of dot rows constituting a character, and the carrier number based on a signal from the detection means. This is achieved by a printer characterized in that it is equipped with means for changing print control parameters such as running speed, and is capable of mounting print heads with different dot pitches.

Embodiments of the present invention will be described in detail below with reference to the drawings.

[Embodiments of the invention]

FIG. 1 is a block diagram of hardware showing an embodiment of the present invention. The printer shown in this embodiment is controlled by a microprocessor 1, and includes the following means connected via a path line 2: a ROM 3. RAM 4, ■/○ boat 5A that holds dot patterns corresponding to each wire of the print head 12;
■/○ port 5B for holding the phase advance data of the two pulse motors 13.1/l and inputting the status of switches, sensors, etc. 15, transmitting and receiving print data with the host device 24, and operating panel ■/○ port 5C, which controls the interface with 16, drivers 8 to 10 and receiver 11. It consists of a timer 17 for setting the phase advance timing of the pulse motor and the drive timing of the print head.

FIG. 2 shows a print head 12A with two different characteristics.
, 12B. Print head 12A, 12B
are respectively provided with plugs 12a and 12b such as those provided on a printed wiring board, and the connection state is taken out as a signal and sent via the receiver 11 to the I10.
Connected to port 5B.

The microprocessor 1 can know the type of print head by reading the contents of the I10 port 5B.

In FIG. 2, 12A corresponds to a dot pitch of 1/160 inch, and 12B corresponds to a dot pitch of 1/180 inch.
When the print head 12B is used, the signal level can be identified as Loty, and when the print head 12B is used, the signal level can be identified as High.

FIG. 3 is a diagram showing differences in control corresponding to differences in dot pitch between the two types of print heads.

By switching these controls using the aforementioned dot pitch signal, desired printing can be achieved.

A method for realizing each item shown in FIG. 3 will be described below.

First, please refer to FIG. 4 for the one-line buffer size. In the figure, 4 is a line buffer, 6 is a printing surface, C1, C2, . . . Cn are printed characters, CP is their pitch, DI, D2, . ...Dn indicates a dot row, and DP indicates its pitch.

In this embodiment, as shown in FIG. 4, the number of buffers is equal to the number of dot rows in the printing surface 6, that is, the number of buffers equal to the number of printing surface length divided by the dot pitch. For example, if the printing width is 13.2 inches, the dot pitch is 1
/160 inch, there will be 2112 dot rows, and if the dot pitch is 1/180 inch, there will be 2376 dot rows.

Therefore, as the dot pitch changes, the buffer size within the printer changes, and this is achieved by changing the number of data that can be received, that is, the data storage upper limit for determining whether the buffer is full.

The number of dot rows constituting the characters of the second item will be explained with reference to FIG. When the dot pitch changes, the number of dot rows that make up a character changes. This is because the size of the characters is fixed, and FIG. 5 shows this situation.

In the figure, (A) is 1/160 inch, CB) is 1/180 inch, and the constituent dots of alphanumeric (ANK) characters (1/10 inch) and Kanji (3720 inch) are shown. The numbers are shown; the vertical axis corresponds to the 24 wires of the print head, and the horizontal axis corresponds to the number of constituent dot rows. Note that the X mark indicates a space.

FIG. 6 shows a brochure of processing for creating the number of dot rows corresponding to the dot pitch in this manner. 6th
The process shown in the figure shows a commonly used method of changing the character amount margin.

Regarding the third item, the traveling speed of the carrier, it is possible to change it according to the change in dot pitch, as in the method described above, but from the viewpoint of the required performance of the printing dots, the smaller the dot pitch, the better. The number of strokes per unit time to obtain printing speed increases, and a high-performance print head is required.

Therefore, when it becomes necessary to change the traveling speed of the carrier so that the number of strokes per unit time remains the same even if the dot pitch changes, the traveling speed of the carrier is determined as shown in Figure 3. This can be achieved by rotating a motor at a certain speed.

The specific control associated with the above switching is performed by a program inside the printer. FIG. 7 shows a block diagram of the control program for the printer of this embodiment. Detailed information on the functions of each block will be explained below.

(1) Input processing (18): Receive print data from the host device 24 and store it in the line buffer. It also reports the status of the printer to the host device 24.

(2) Character generator (19): Has a character design (dot string data) table corresponding to the character coat.

(3) Print control (20): Starts motor control and print head control based on the print command received in input processing (18).

(4) Initializer (21): When the power is turned on, a reset instruction returns the printer state and program state to the initial state.

(5) Motor control (22): Controls the rotation of the carrier motor and line feed motor according to instructions from the print control (20).

(6) Print head control (23): Outputs the contents of the line buffer to the print head in synchronization with the rotation of the motor.

(7) Status control (25): Operation panel 16. It reads each signal from the switch, sensor 15, etc. and controls the state of the printer.

An overview of the operation of the printer of this embodiment will be described below with reference to FIG.

Print data and control codes from the host device 24 are received by the input processing 18, and the print data is developed into a print head drive pattern via the character generator 19 and stored in the line buffer (RAM) 4.

When receiving a control code that triggers printing or detecting that the line buffer is full, the print start position for printing,
Motor control with end position and line feed data added 22. Print head control 23 is activated.

Thereby, in synchronization with the rotation of the carrier motor 13, the print head control 23 sequentially takes out data from the row buffer 4 and supplies it to the print head 12.

The print control 20 waits until printing is completed, and when it is completed, starts the input processing 18 again.

Printing is continued by repeating the above operations.

In the printer shown in this embodiment, by using the configuration and control operations as described above, it is possible to realize a printer in which a plurality of print heads having different pitches can be mounted on one drive.

Furthermore, by configuring the printer to report the detection result of the type of print head to the host device, the host device can recognize the dot pitch of the printer, and the host device can control the printer accordingly. Become. This is 1,
For example, in a graphic printer, this is extremely important when editing data.

〔Effect of the invention〕

As described above, according to the present invention, it is possible to print at a desired dot pitch by allowing the operator to replace the print head, so even systems that require multiple dot pitches can be handled with one printer. Therefore, it is effective in simplifying the system and lowering the price of the system.

Furthermore, if a means for notifying the dot pitch to the higher-level device is provided, the higher-level device can check the dot pitch, allowing more detailed control, and improving performance can be expected. This is essential for graphic printers.

[Brief explanation of drawings]

Fig. 1 is a configuration diagram showing an embodiment of the present invention, Fig. 2 is an illustration for explaining a method of detecting a difference between two different print heads, and Fig. 3 is an illustration for explaining a difference in control for a difference in dot pitch. Figure 4 is a diagram showing the configuration of the line buffer, Figure 5 is a diagram to explain the difference in character configuration due to differences in dot pitch, and Figure 6 is a diagram to create the number of dot columns corresponding to the dot pitch. The flowchart of the process, FIG. 7, is a diagram showing an example of the configuration of the control program. l: Microprocessor, 3: ROM, 4: RAM, 5
A, 5B, 5C: I/○ boat, 8-10: Driver, 11: Receiver, 12: Print head, 18 Two-man processing, 19: Character generator, 20: Print control, 2
2: Motor control, 23: Print head control, No.
1 Figure 2 Figure 3 Figure Φ Figure 5 Figure 7

Claims (1)

[Claims] (1) In a serial dot printer that prints line by line using a print head, there is a means for detecting the dot pitch of the print head, and a signal from the detecting means to determine the print data buffer size, the number of dot rows constituting a character, and the carrier travel. A serial dot printer characterized in that it is provided with means for changing print control parameters such as speed, and is capable of mounting print heads with different dot pitches.