JPH0364314B2 - - Google Patents

Description

[Detailed Description of the Invention] (1) Technical Field of the Invention The present invention is a serial dot printer that, when a power supply drop due to overload is detected while printing a line-by-row pattern, can print the remaining print pattern in multiple batches. The present invention relates to a load printing control method.

(2) Prior art and problems Conventionally, when a serial dot printer detects that the power supply voltage has dropped due to overload while printing a pattern for each line, it temporarily ends printing, returns to the beginning of the line, and prints the entire line. The pattern was reprinted two or three times. Therefore, already printed patterns are printed repeatedly, causing problems such as differences in shading and double printing, deterioration of printing quality, and time consuming due to the redundant printing.

(3) Purpose of the Invention The purpose of the present invention is to provide an overload printing control method that allows a serial printer to continue printing quickly and with good quality when a power drop due to an overload is detected during pattern printing for each row of a serial printer. It is to provide.

(4) Structure of the Invention The overload printing control method of the present invention moves a printing head having a plurality of dot printing elements arranged along the paper feeding direction in the space direction, and prints the dots at a timing synchronized with the movement. In a serial printer that forms dots by driving a printing element and prints a pattern line by line, voltage detection means detects when the voltage value for driving the dot printing element of the printing head has fallen below a predetermined value. When a drop in the voltage value is detected by the voltage detecting means during printing of a certain line, the printing head moves the unprinted area of that line several times by space, and each movement The present invention is characterized in that by driving and controlling different dot printing elements, only patterns excluding patterns that have already been printed are printed separately in the paper feeding direction, and printing of that line is completed.

(5) Examples of the invention FIGS. 1a and 1b are explanatory diagrams of the principle of the present invention.

Now, in a serial dot printer, if one character is printed with 24 x 24 dots, the pattern formed by dot pin rows #1 to #24 is sequentially fired, and as shown in pattern 1 in the left half of figure a, the pattern is fired in the space direction. At each timing, all dots corresponding to the pattern are fired.

As a result, when a drop in the power supply voltage is detected at time t ₀ (black ▼ mark) in the middle of a line, printing is not terminated and the remaining pattern 2 of the line is changed at each timing t ₁ ,
For t ₂ , t ₃ ...t _o, the dot pin rows #1 to #24 are divided into odd and even numbers, and in the first printing, the odd numbers #1, #3, ... as shown in a in the same figure. #twenty three
As shown in Figure b, in the second printing, there is no duplicate printing until t _{0 .}
For each subsequent timing t ₁ , t ₂ , t _{3 .}

This reduces the power supply load by half, which is useful for restoring the power supply voltage. However, since the power supply voltage is also related to other loads, it is necessary to constantly detect this voltage drop and take appropriate measures.

FIG. 2 is an explanatory diagram of the configuration of an embodiment of the present invention according to the above principle, and FIG. 3 is a flowchart showing its operation.

In FIG. 3, an information processing unit (CPU) 10
A power supply voltage detection circuit 11 is connected to the CPU 10, and when the power supply voltage drops below a predetermined threshold value due to overload or the like, the information is sent to the CPU 10. When the power supply voltage is normal, the print data from the CPU 10 is sent to the print control circuit 1 simultaneously.
2, all dot pin rows are printed at each timing as shown in pattern 1 in the left half of FIG. 1a. Here, if the power supply voltage falls below a predetermined threshold, the print data is sent to the odd number print control circuit 13, and controlled so that odd numbered dots are printed at each timing after time _t0 . After the final timing of this line, the printing is switched to the even-numbered dot, and the print data is then sent to the even-numbered print control circuit 14, and the even-numbered dot is printed at each timing after the same time point _t0 as described above. Furthermore, in this case, the control is such that duplicate printing at each timing from 0 to _t0 is cleared. Control signals from the CPU 10 to each of the control circuits 12, 13, and 14 drive the corresponding mechanical parts through the drive control circuit 15.

FIG. 3 shows the flow of operations in lines illustrating the above-mentioned operations. In other words, after the start, it is checked whether or not there are two strokes through the procedure. If the two strokes are not, a drop in the power supply voltage is checked. If the voltage is normal, simultaneous printing is performed as shown in Figure 2, and upon completion, the next The line is repeated.

In the case of being struck twice or in the case of a drop in the power supply voltage, the number of times N since the time t ₀ is checked, and N =
If it is 0, printing of odd numbers #1, #3..., #23 of the dot pin row is repeated after timing _t1 ,
When the last character is completed, the number of times N is increased by 1, and the process returns to the step 1. This time, the even number printing is repeated with N=1, and when the last character is completed, the number of times N is struck twice to clear the number of times N. Upon completion of this process, the process moves to the next line.

In the embodiment, when a power supply voltage drop is detected,
Although the dot row is divided into odd and even halves, for example, 24 dots may be divided into three corresponding to 1 byte of 8 bits, or may be divided into n according to the dot row (number of pins).

(6) Effects of the Invention As explained above, according to the present invention, when a power drop due to overload is detected while printing a line-by-row pattern in a serial dot printer, the remaining print pattern is printed in multiple batches. This is used to switch the pattern so that it continues to be printed. As a result, printing is not terminated when the power supply voltage drops, and control is performed to avoid duplicate printing, so there is no deterioration in print quality due to duplicate printing.
In addition, since there is no duplicate printing, printing time can be shortened.

[Brief explanation of drawings]

1A and 1B are diagrams explaining the principle of the present invention, FIG. 2 is a diagram explaining the configuration of an embodiment of the present invention, FIG. 3 is a flowchart showing the operation of the embodiment, and 10 is an information processing device (CPU). , 11 is a power supply voltage detection circuit, 12 is a simultaneous printing control circuit, 13 is an odd number printing control circuit, 14 is an even number printing control circuit, and 15 is a drive control circuit.

Claims (1)

[Claims] 1. A method for printing dots by moving a printing head having a plurality of dot printing elements arranged along the paper feeding direction in the space direction and driving the dot printing elements at a timing synchronized with the movement. A serial printer that prints a pattern on a line-by-line basis has a voltage detection means that detects when the voltage value for driving the dot printing element of the print head has fallen below a predetermined value, and when a certain line is being printed. When a drop in the voltage value is detected by the voltage detecting means, the printing head moves the unprinted area of the row in multiple spaces, and drives and controls different dot printing elements for each movement. An overload printing control method characterized in that by doing so, only patterns excluding patterns that have already been printed are dividedly printed in the paper feeding direction and printing of that line is completed.