JPH0211357A - Printing apparatus - Google Patents

Abstract

PURPOSE:To increase the speed of printing operation by replacing the control code of a block having no printing data with a paper feed control code by a control means when a blank data is detected. CONSTITUTION:The printing data stored in a page memory 7 is copied on a line buffer 11 at every one line by a drawing processor 10 and edited so as to be capable of being printed by a printer mechanism part 8. When a blank detection circuit 12 is reset, the copy of the printing data from the page memory 7 due to the drawing processor 10 is started and the drawing processor 10 repeats the reading from the page memory 7 and the writing to the line buffer 11. At this time, the write pulse signal from the drawing processor 10 becomes active and the flip-flop 14 of the blank detection circuit 12 latches an OR-signal. When the copy to the line buffer 11 by the drawing processor 10 is finished, the presence of blank data is judged and accumulated line feed quantity is set to a paper feed control code part.

Description

DETAILED DESCRIPTION OF THE INVENTION [Object of the Invention] (Field of Industrial Application) The present invention relates to a printing device that prints print data transferred from a host computer or other host device onto paper.

(Prior art) Generally, when outputting print data transferred from a host computer, a page printer organizes and prints print data for each page, and prints data for each line. Printing devices such as a line printer that organizes and prints data and a serial printer that organizes and prints print data character by character are used.

Recently, as memory chips have become more highly integrated and lower in price, printing devices equipped with page memories have become mainstream.

In a printing device equipped with such a page memory, print data such as enlarged characters or complex graph images transferred from the host computer is changed to character pattern data in the font memory for each page, and then the data is transferred to the font memory. By expanding the page memory into the page memory, output control from the page memory can be performed using relatively simple logic.

In other words, for example, in a page printer that uses a laser beam, a control circuit sequentially scans the page memory to access data, converts this data into serial data, and then transfers it to the printing mechanism via a mechanical interface at a constant clock. ing.

Thereafter, in the printing mechanism section, information is printed on the printing paper via a rotating drum that rotates at a constant speed.

On the other hand, similar data output control is possible with the above-mentioned line printers and serial printers.

However, since the interface of the printing mechanism is fundamentally different, the page memory data is divided into units of a fixed width (
scan block), store it in the line buffer,
After editing to add a control code, the data is generally transferred by a transfer circuit of the printer interface.

(Problem to be Solved by the Invention) By the way, when printing as shown in FIG. 7 is performed by the above-mentioned conventional printing device, partial margins in the line direction (portions a-c in the figure) are printed. ) occurs.

For this reason, the print head moves even in this margin based on blank data, which not only wastes data transfer but also hinders speeding up of printing operations.

The present invention was made in view of the above circumstances, and an object of the present invention is to provide a printing device that can speed up printing operations.

[Configuration of the Invention (Means for Solving the Problems) In order to achieve the above object, the printing device of the present invention includes a first storage means for storing print data transferred from a host device; A second storage unit that stores the print data stored in the storage means in each predetermined block and adds a control code to the print data in each block, and then transfers the print data to the print mechanism that performs printing based on the print data. and a blank for detecting blank data in each block stored in the second storage means when printing data stored in the first storage means is expanded block by block to the second storage means. The blank detection circuit includes a detection circuit and a control means for controlling the blocks in which there is no print data to replace the control code with a paper feed control code based on the detection result of the blank detection circuit.

(Function) In the printing device of the present invention, when the blank detection circuit detects blank data in each block stored in the second storage means, the control means controls the printing data based on the detection result of the blank detection circuit. Controls the control codes of missing blocks to be replaced with paper feed control codes.

(Example) Hereinafter, details of an example of the present invention will be described based on the drawings.

FIG. 1 shows an embodiment in which the present invention is applied to a line printer.

As shown in the figure, the line printer is equipped with a microprocessor bus 1.

This microprocessor bus 1 includes a host interface 3 that changes the format of print data from a host computer 2 that is a host device, a microprocessor 4 that controls the operation of each component on the line printer side, and a microprocessor 4 that controls the operation of each component on the line printer side. A program storage unit 5 that stores control orders and program logic is connected.

The line printer is also equipped with an image bus 6.

The image bus 6 includes a page memory 7 that stores print data for one page, a printer interface 9 that transfers the print data from the page memory 7 to the printer mechanism 8, and a A drawing processor 10 that transfers print data between the processor bus 1 and the image bus 6 and draws figures.
．． A line buffer 11 for editing one line of print data (adding a control code, etc.) and a blank detection circuit 12 for detecting blank data are connected.

The blank detection circuit 12 includes an OR circuit 13 and a flip-flop (r'/F) 14.

In the figure, 15 is a line for transferring the write pulse signal from the drawing processor 10 to the flip-flop (P/F) 14, and 16 is a line for transferring the output signal from the OR circuit 13 to the flip-flop (P/P) 14. , 17 is a line that transfers a signal that becomes active when print data exists during transfer from the page memory 7 to the line buffer 11 by the drawing processor 10, and 18 is a blank detection circuit 12 from the microprocessor 4. This is the line that transfers the signal to reset the .

FIG. 2 shows the page memory 7 and line buffer 11 described above.

As shown in the figure, the page memory 7 stores print data from the host computer 2, such as print data of a character m or a graph image g. These print data are formed into scan blocks numbered 1 to 11 with the width of one line buffer 11 (n dot width). However, since scan block No. 11 is a fraction, it has a width of m dots (m≦n).

The line buffer 11 is provided with dot image sections 11a, 11a, . n or 4n indicates the number of line feed dots, and FF indicates a page break code.

When the drawing processor 10 starts cutting out print data from the page memory 7, the print data is copied to the line buffer 11 in this order from 5LBI to 5LB7.

Next, the operation of the above-mentioned line printer will be explained using FIG. 3.

First, when print data for one page is transferred from the host computer 2, these print data are stored in the page memory 7 via the host interface 3.

Next, the print data stored in the page memory 7 is 1
The line buffer 1 is created by the drawing processor 10 for each line.
1, and here the print data is copied to the printer mechanism section 8.
is edited so that it is printable.

At this time, first, the line buffer (SLB) 11 (5LBI to 5L in Figure 2) used in (step 1)
B7) To obtain the accumulated line feed amount (Acmslw)
Initialize. Next, in (step 2), after performing initial settings for cutting out, the line buffer (CLB) 11 for copying (the dot image section 1 in FIG.
Obtain 1a). Next, when the cutting out of the print data from the page memory 7 is started, it is determined whether the cutting out has been completed (step 3).

If the extraction has not been completed, the address and number of bytes of the scan block of the page memory 7 to be extracted are counted (step 4).

At this time, in (step 5) the blank detection circuit 1
2 is reset, the drawing processor 10 starts copying print data from the page memory 7.

When the drawing processor 10 starts copying, the drawing processor 10 repeats reading from the page memory 7 and writing to the line buffer 11. At this time, when the drawing processor 10 writes to the line buffer 11, the write pulse signal from the drawing processor 10 becomes active, so that the flip-flop 14 of the blank detection circuit 12 latches the OR signal.

As a result, the OR signal is made up of each bit of the write data and a "non-blank signal" immediately before writing, so it indicates the presence or absence of blank data at the end of copying.

Next, the line buffer 11 by the drawing processor 10
When the copy to (step 6) is completed, (step 7
), the presence or absence of blank data is determined. That is, when scan block No. 1 is copied in FIG. 2, since there is no print data in this scan block No. 1, it is determined as "blank" as a result of blank detection.

If there is a blank, the vertical dot width V of the scan block is added to the accumulated line feed ff1 (Ac+aslv) (step 8).

If the blank detection result is "non-blank", the accumulated line feed amount (Acmslv)-n is set in the paper feed control code section 11b of SLB 1 in FIG. 2 (step 9).

At this time, since there is no print data in scan blocks N083 to N085 in FIG. 2, the result of blank detection is determined to be "non-blank". In this case, the accumulated line feed amount (AcIIslv) -
Set m 4n.

In addition, scan blocks No. 6 to 10 in FIG.
Since there is print data, the accumulated line feed i (Acm
sly)-n.

However, in the case of scan block No. 11, which is a fraction, the accumulated line feed ffi (Acmslv) -m is used, but since this scan block No. ll is the last to be cut out, each paper feed control code section 11b of 5LB7 A page break code (PP) is set to (Step 12)
~(Step 13).

Thereafter, in step 14, transfer to the printer 8 is activated.

When applied to a serial printer, it is necessary to detect blanks on the left and right sides of one line of print data, as shown in FIG. In this case, as shown in FIG. 5, the digit direction is first divided into pieces as large as the character width. Next, when copying from the page memory 7 to the line buffer 11, the blank detection circuit 12 detects blanks on the left and right sides of one line of print data.

At this time, for example, as shown in FIG.
o, 1.2, 5, and 8.9 are "blank".

Thereafter, digit direction division numbers 1 and 2 are replaced with write margin setting control codes and set in the line buffer 11, and digit direction division numbers 8 and 9 are omitted.

As a result, the data transfer based on the print data of the digit direction division number 8.9 and the accompanying movement of the print head can be omitted, so that it is possible to speed up the printing operation.

As described above, in this embodiment, based on the detection result of the blank detection circuit 12, the drawing processor 10 replaces scan blocks with no print data with paper feed control codes, and replaces scan blocks with print data with paper feed control codes. Line buffer 11 to omit trailing blank data
storage operations can be controlled.

As a result, it is possible to eliminate extra data transfer based on print data and the associated extra movement of the print head.

In this embodiment, the print data from the host computer 2 was explained as a character m and a graph image g.
However, if the print data is a text image, additional movement of the print head can be further eliminated.

That is, if the text image is ANK whose character size is smaller than that of Kanji, the scan block width can be made smaller.

[Effects of the Invention] As explained above, according to the printing device of the present invention, when the blank detection circuit detects blank data in each block stored in the second storage means, the detection result of the blank detection circuit is Based on this, the control means controls to replace the control code of a block with no print data with the paper feed control code, so that the speed of the printing operation can be increased.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing an embodiment of the present invention applied to a line printer, FIG. 2 is a diagram showing how print data is stored in the page memory and line buffer of FIG. 1, and FIG. FIG. 1 is a flowchart showing the operation of a line printer, FIGS. 4 to 6 are diagrams showing blanking control when the present invention is applied to a serial printer, and FIG. 7 is a diagram showing an example of printing by a conventional printing device. It is. DESCRIPTION OF SYMBOLS 1...Microprocessor bus, 2...Host computer, 3...Upper interface, 4...Microprocessor, 5...Program storage unit, 6...
Image bus, 7... Page memory, 8... Printer mechanism section, 9... Printer interface, 10...
・Drawing processor, 11...Line buffer, 12・
...Plan detection circuit, 3...OR circuit, ...flip float.

Claims (1)

[Claims] (1) A first storage unit that stores print data transferred from a host device, and stores the print data stored in the first storage unit in each predetermined block, and controls the print data in each block. After adding the code, a second storage means transfers the print data to a printing mechanism that performs printing based on the print data; and a second storage means that transfers the print data stored in the first storage means for each block. A blank detection circuit detects blank data in each block stored in the second storage means when the data is expanded to the storage means, and based on the detection result of this blank detection circuit, the blocks without the print data are 1. A printing device comprising: control means for controlling the control code to be replaced with a paper feed control code.