JPH06171153A - Method of printing dot matrix printer - Google Patents

Abstract

PURPOSE:To improve total throughput by a method wherein when dot density is detected to be below a constant value using a dot density detecting means, spacing speed is changed over to a speed higher than a spacing speed when the dot density is equal to or higher than a constant value. CONSTITUTION:When a CPU 1 writes one line for the next line in a printing data memory 4, the content thereof is transferred to a dot density detection circuit 5, following which when the CPU 1 instructs, for example, that a dot interval is 2 for the circuit 5, a start address and end address in an area of printing data memory wherein the dot interval is 2 or more are determined. Next, the distance required for accelerating a spacing motor 11 to a spacing speed 2v for the dot interval of 2 from the spacing speed v for the dot interval of 1 is instructed. Then the circuit 5 determines start and end addresses of the area of the memory 4 which satisfy the distance value. In this manner, total printing time is reduced.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a printing system in a dot matrix printer.

[0002]

2. Description of the Related Art In a dot matrix printer, in order to increase the printing speed, an area in which the printed result is blank is detected, and the spacing speed of the empty area is set to be faster than the printed area. Has been known for a long time.

FIG. 4 is a diagram showing an example of a conventional printing method in the relationship between the printing result and the spacing speed. As is apparent from FIG. 4, in the conventional printing method, the spacing speed is determined by detecting whether there is print data to be printed or blank in the print area of the print output waiting data. It was That is, in FIG. 4, an area a is an area where print data to be printed exists, and an area b is a blank area where there is no print data to be printed, and the spacing speed of the area b is different from the spacing speed of the area a. Is controlled to be about twice as fast.

[0004]

However, in the above-mentioned conventional printing method, the spacing is detected only by detecting whether there is print data to be printed or blank in the print area in the print output waiting data. The speed was decided.
Therefore, the spacing speed of the print area is the same as that of a portion having a high dot density, however low the dot density of that portion is.

Therefore, the conventional printing method has a drawback that the ability of the matrix constituent elements (maximum driving frequency) is not sufficiently exerted when printing a portion having a low dot density, and the total throughput cannot be increased.

The present invention has been made in view of the above problems, and an object of the present invention is to provide a printing method for a dot matrix printer which can provide a printing apparatus with excellent total throughput.

[0007]

In order to achieve the above object, the dot matrix printer printing method according to the present invention detects an area where a print result is blank and prints a spacing speed of the blank area. The detection means for detecting the dot density of the matrix constituent elements in the print area in the print output waiting data, and the control means for switching the spacing speed by the output of the dot density detection means. When the dot density detecting means detects that the dot densities of all the matrix constituent elements are below a certain value, the spacing is faster than the spacing speed when the dot density is above the certain value. It is designed to switch to speed.

[0008]

According to this structure, the dot density is detected for each matrix constituent element in the print area in the print output waiting data, and the spacing speed is changed according to the value of the dot density for each matrix constituent element. A dot matrix printer that can be expected to improve and has a high printing speed can be obtained.

[0009]

Embodiments of the present invention will be described in detail below with reference to the drawings. FIG. 1 is a control block diagram of a dot matrix printer shown as an embodiment of the present invention.

In FIG. 1, in this printer, the CPU
(Central processing unit) 1 and address bus 2 for this CPU 1
And a print data memory 4, a dot density detection circuit 5, a print head control circuit 6, a spacing motor control circuit 7, and a print head drive circuit connected to the print head control circuit 6 respectively. 8 and the print head 10, a spacing motor drive circuit 9 and a spacing motor 11 connected to the spacing motor control circuit 7.

In this control configuration, the CPU 1
Obtains the data to be printed in the next line, writes this data in the print data memory 4, and detects the dot density of the matrix constituent elements from this data. To simplify the explanation here, Print head 1 for print data
Assuming that the number of matrix constituent elements of 0 is 8, the print data here is FFH if data is printed by all matrix constituent elements, and is data if all matrix constituent elements are not printed. OOH, if the data for printing only the first matrix constituent elements is 80H, each bit of the print data is the print head 1
It corresponds to 0 matrix constituent elements.

The address of the print data memory 4 is
It corresponds to the minimum pitch (for example, 1/180 inch) in the spacing direction at the time of printing, and when paying attention to the bit corresponding to one matrix constituent element, the same bit of the adjacent address is "1". In this case, the dot density is the highest, and it can be said that the dot density is lower as the address interval between two adjacent "1" bits is larger.

FIG. 2 is a diagram showing an example of the data contents written in the print data memory 4 and the data broken down into the elements until the spacing speed is determined. In FIG. 2, (A) is each address (0-9, AF, 10-19, 1A, 1B, etc.) in the print data memory 4.
() Indicates the written data content, and in this data content, "1" is data that requires printing within the corresponding address, and "0" is data that does not require printing. Further, in FIG. 2, (B) is an area c in which all the matrix constituent elements have a dot spacing of 2 or more, (C) is an area d in which all the matrix constituent elements have a dot spacing of 5 or more, and (D) is all. Shows a region e in which the dot spacing is 4 or more, and (E) shows an example of the spacing speed determined in consideration of the above (B) to (D).

Therefore, the operation for determining the spacing speed in the control configuration shown in FIG. 1 will be described below by taking the data shown in FIG. 2 as an example. First, the CPU 1 obtains the data to be printed on the next line, and when the print data for one line is completely written in the print data memory 4 as shown in FIG. Direct memory access (commonly known as "D" to the dot density detection circuit 5)
Call it "MA".

After that, when the CPU 1 designates the detected dot density (for example, the dot interval is 2) to the dot density detection circuit 5, the dot density detection circuit 5 makes a matrix as shown in FIG. The component detects the area c of the print data memory in which the dot interval is 2 or more, and this area c
The start address (address number 2) and the end address (address number 18) are calculated.

Next, the CPU 1 uses the dot density detection circuit 5
In addition, it is necessary to accelerate the spacing motor 11 from the spacing speed v when printing the print data with the dot interval of 1 to the spacing speed 2v when printing the print data with the dot interval of 2. A value obtained by converting the distance into a dot interval (5 in the example of FIG. 2) is designated. Then, as shown in FIG. 2C, similarly to the above, the dot density detection circuit 5 detects the area d of the print data memory 4 that satisfies this value, and the start address (address number 4) of this area d. ) And the end address (address number 9).

Similarly, when the CPU 1 designates a value (4 in the example of FIG. 2) obtained by converting the distance required for decelerating the spacing motor 11 to the spacing speed v from the spacing speed 2v (4 in the example of FIG. 2). As shown in FIG. 2D, the dot density detection circuit 5 detects a region e of the print data memory 4 that satisfies this value, and the start address (address numbers 4 and 14) and end address of this region e are detected. (Address number 9, 18) is calculated.

That is, the CPU 1 has the above information (B).
From (D), where is the low dot density area in the print data of one line to be printed?
Knowing where is the acceleration area required to print this area at high speed, and where is the deceleration area for transitioning to the area with a high dot density again, one line is shown in Figure (E). Print the spacing speed.

Then, a region d and a region e are included in the region c.
However, only when at least one set is included in this order, the area between the area d and the area e is fast (speed 2
Print with v).

Therefore, for example, as shown in FIG. 3, assuming that the maximum driving period of the matrix constituent elements is the time T, the dot data as shown in FIG. 2 is changed by the spacing speed v in the conventional printing method. In the printing method of the present embodiment, what was printed was detected to have a dot interval of 2Tv in the maximum dot density portion, and this interval 2T
Spacing speed 2v so that v is printed at time T
Since it is (2 Tv / T), the overall printing time can be reduced. In particular, the method of the present embodiment is effective in the case of printing vertical ruled lines of a 1-dot row having a relatively long interval. In addition, since the dot density is detected for each matrix constituent element, it is possible to perform high-speed spacing for areas where the dot density value in the print area is below a certain value (rough density), and total throughput can be increased. Can be expected to improve.

[0021]

As described above, in the printing method of the dot matrix printer according to the present invention, the dot density is detected for each matrix constituent element in the print area in the print output waiting data, and the dot density for each matrix constituent element is detected. Since the spacing speed is changed depending on the value of, the total throughput can be expected to be improved and a dot matrix printer with high printing speed can be obtained.

[Brief description of drawings]

FIG. 1 is a control configuration block diagram of a dot matrix printer shown as an embodiment of the present invention.

FIG. 2 is a diagram showing a relationship between an example of data content written in a print data memory and a spacing speed.

FIG. 3 is a comparative explanatory diagram of a conventional printing method and a printing method of this embodiment.

FIG. 4 is a relationship diagram between a printing result and a spacing speed in a conventional printing method.

[Explanation of symbols]

 1 CPU (Central Processing Unit) 2 Address Bus 3 Data Bus 4 Print Data Memory 5 Dot Density Detection Circuit 6 Print Head Control Circuit 7 Spacing Motor Control Circuit 8 Print Head Drive Circuit 9 Spacing Motor Drive Circuit 10 Print Head 11 Spacing motor

Claims (1)

[Claims] 1. A printing method for a dot matrix printer, which detects an area where a print result is blank and makes a spacing speed of the blank area faster than an area to be printed, in a print area in print output waiting data. Detecting means for detecting the dot density of the matrix constituent elements and control means for switching the spacing speed by the output of the dot density detecting means are provided, and the dot density of all the matrix constituent elements is constant by the dot density detecting means. A printing method for a dot matrix printer characterized in that, when it is detected that the value is below a certain value, the spacing speed is switched to a faster spacing speed than when the dot density is above a certain value.