JPH0234790B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to a control device for a dot printing device in which a plurality of printing hammers having dot elements are arranged horizontally and these printing hammers are reciprocated in the digit direction to print. Such a dot printing device reciprocates a group of printing hammers across a printing paper, and in the process of this reciprocating movement, drives the printing hammers to print.
That is, one line of dots is printed in the horizontal direction in one direction of the reciprocating motion, and then the printing paper is advanced to the next vertical dot printing position, and then one line of dots is printed in one direction of the reciprocating motion. This operation is repeated a predetermined number of times to form and print characters consisting of a predetermined number of dots in a matrix in the horizontal and vertical directions. When printing alpha characters, numbers, symbols, katakana, etc., a print data code is transferred from a host device such as a CPU, and this print data is temporarily stored in a print data buffer (hereinafter referred to as PLB).
When the transfer of print data for one line is completed, a data transfer end command is transferred, and the printing device starts printing. To print the specified characters in each digit, use the character generator (hereinafter referred to as
CG), the required dot pattern information is read out by comparing the horizontal and vertical positions.
This is done by driving the printing hammer according to the information. There are various numbers of dots that make up a character, but a matrix configuration of 5 dots in the horizontal direction and 7 dots in the vertical direction will be explained. An example of printing with this character structure is shown in FIG. 1, and pattern information in the CG for characters 1 and 2 is shown in Tables 1 and 2, respectively. In this character structure, the dot matrix is 5 horizontally and 7 vertically.
It consists of 35 dots.

【table】

[Table] When printing the above-mentioned alphanumeric characters, numbers, katakana, etc., it is not necessary to print all 35 dots; on average, about 40% of the dots, and at most about 60%, can be used to form characters. Therefore, the performance of the printing hammer and its drive circuit, etc.
It is sufficient to withstand approximately 60% of the continuous operation of 35 dots. On the other hand, the dot printing device not only prints characters using dots as described above, but also can print dots at any position on printing paper. (also large characters) can be printed. When printing these figures and large characters, a dot print pattern of one dot line in the horizontal direction is transferred from the host device, and this method will be explained below. It was mentioned earlier that characters such as alphabets, numbers, and katakana are composed of five dots in the horizontal direction, but in order to maintain space between each character, an interval of one dot is provided. Therefore, the number of horizontal dots in one digit is six. The code transferred from the host device is normally 7 or 8 bits. By making 6 bits of these bits correspond to the 6 horizontal bits of each digit, it becomes possible to print dots at arbitrary dot positions as follows. A case in which a part of the figure shown in FIG. 2 is drawn will be described. Print dots at the positions indicated by circles in the 1st, 2nd, and 3rd digits of vertical position 1. The PLB consists of 8 bits for each digit, of which 6 bits, bits 1 to 6 are used (all 8 bits are used for alphanumeric characters, symbols, and katakana codes). Bit 1 corresponds to horizontal position 1 of each digit,
Bit 2 is horizontal position 2, and so on, bit 6 is
corresponds to horizontal position 6. Bits 7 and 8 are ignored. Further, before the PLB starts printing at vertical positions 1 to 4, print data at each vertical position is transferred, and examples thereof are shown in Tables 3 to 6 in correspondence with FIG. Note that the position where dots are printed is set to a logical value of 1, and the position where no dots are printed is set to a logical value of 0 (x indicates that either a logical value of 1 or 0 may be used).

【table】

【table】

【table】

【table】

[Table] When transferring such a dot print pattern of 1 dot line in the horizontal direction, and before starting printing with the 1 dot line transfer end command, check that the transferred data is a dot print pattern rather than a code indicating a character. A command indicating that the code is currently being transferred is transferred, or another signal is used to indicate that the code currently being transferred is a dot printing pattern, or a switch or the like is used to make the printing device recognize it. When the printing device recognizes that the printing pattern is a dot print pattern, without reading the dot pattern information from the CG, it collates the horizontal position from the dot print pattern on the PLB, reads the necessary bit information, and drives the printing hammer. to print figures, large characters, etc. In this case, since it is possible to print at any dot position, at most 60% of the 35 dots can be printed, as in the case of letters.
It cannot be said that only one dot is printed, and furthermore, the number of dots increases by one dot for each digit in the horizontal direction, so strict performance is required of the printing hammer and its drive circuit. Configuring the printing hammer, its driving circuit, etc. to withstand this worst case inevitably increases the price of the printing device. In addition, the cooling device as a countermeasure against the heat generation of the coil of the printing hammer is also enlarged, resulting in various disadvantages such as an increase in the weight of the printing device and an increase in power consumption when a blower or the like is used. An object of the present invention is to eliminate the above-described drawbacks of the prior art, to enable a printing device to be manufactured at low cost without reducing the actual printing speed, and to reduce weight and power consumption. The present invention monitors the code transferred from the host device, adds the information to be printed by one dot line, and if the number is larger than a predetermined number, prints that one dot line one round trip (twice each way). The present invention is characterized in that the printing is completed at the point where the printing is completed, so that the performance of the printing hammer and its drive circuit, etc., is not set more strictly than necessary. The present invention will be explained below with reference to the drawings. Before explaining the control device of the present invention, a case will be explained in which characters such as alphabets, numbers, symbols, and katakana are printed. In FIG. 3, when the printing device becomes capable of receiving print data from the host device 1, the data transfer start signal i becomes a logical value 1, and the flip-flop 9 is reset. The data transfer start signal i is also sent to the host device 1, and the print data a is transferred from the host device 1. Print data a consists of 8 bits and is a code corresponding to a character. This print data a
is determined by a synchronization signal (not shown) from the host device 1.
Written to PLB2. When the host device 1 finishes transferring one line of print data a in this way, the host device 1 sets the one-line data transfer end signal g to a logical value of 1 to notify the printer of the end of data transfer. When the printing device receives this signal, it ends the data reception cycle and shifts to the printing cycle. Since the print data a transferred at this time is a code specifying a character, the plot mode signal h from the host device 1 is a logical 0.
It is. Therefore, flip-flop 9 remains reset, and since the 0 output of flip-flop 9 is at logic 1, hammer drive enable signal l maintains logic 1 during printing of one line. Since the plot mode signal h has a logical value of 0,
AND gate 22 keeps its gate closed. The AND gate 21 to which the output of the inverter 20 is connected opens the gate when the output O of the data select 18 has a logic value of 1, and outputs the logic value of 1.
Then, the print information signal p is sent via the ORGADE 23.
Then, it enters the AND gate 15, the hammer drive signal q becomes logical 1, and the printing hammer is driven.
Dots are printed on the paper. Next, a method for printing dots forming each print at predetermined printing positions will be explained. Print data a to be printed on a certain digit is stored in PLB 2, and when that digit is specified with PLB address C, which is the output of PLB address counter 5,
PLB data d is output. Print data a and
PLB data d is the same. PLB data d
is input to the CG 17 and specifies the block in which the character dot pattern corresponding to the PLB data d is stored. This block consists of 8 bits horizontally and 8 bits vertically. A dot pattern n in the horizontal direction of a certain character is selected based on horizontal position information e consisting of 3 bits from the horizontal position control circuit 7. Horizontal position control circuit 7
The horizontal position information e corresponds to the position of the printing hammer group, and for example, a signal from an encoder connected to an electric motor that drives the printing hammer group is input. This dot pattern consists of 8 bits in the vertical direction. Selecting dot information at a necessary vertical position from the vertical 8-bit dot pattern at a certain horizontal position output in this manner is realized as follows. Upon entering the print cycle, the vertical position control circuit 19 is set to vertical position 1. Then horizontal direction 1
Each time printing of a dot line is completed, it advances to the next dot line. At this time, the vertical position control circuit 19
is incremented by 1, and specified sequentially starting from vertical position 2. Using the vertical position information r from the vertical position control circuit 19, necessary dot information can be selected from among the dot patterns at vertical positions 1 to 8 inputted to the data selector 18. Specifically, the case where the first character 2 is printed will be explained. When a printing cycle begins, the vertical position control circuit 19 is initialized, and the vertical position information r specifies vertical position 1. PLB data d from PLB2 specifies the block in which the dot pattern of character 2 of CG17 is stored. The CG 17 outputs an 8-bit dot pattern n at horizontal position 1 of the dot pattern of character 2 based on the horizontal position information e output from the horizontal position control circuit 7. The data selector 18 outputs the bit at vertical position 1 based on the vertical position information r. Since the output at this time is a logical 0, the print information O has a logical value of 0, and the hammer drive signal also has a logical value of 0. Therefore, in this position, the printing hammer is not energized and no dots are printed. Next, depending on the position of the printing hammer, the horizontal position control circuit 7 sets the horizontal position information e to 2, 3, 4, 5, or 6, and outputs the dot pattern n of the character 2 at each horizontal position from the CG 17. The data selector 18 selects the bit at vertical position 1 from these dot patterns n. When the print information O, which is the output of the data selector 18, has a logical value of 1, the hammer drive signal q has a logical value of 1, and the printing hammer is energized to print a dot. In this case, since the bits at horizontal positions 2, 3, and 4 have a logical value of 1, three dots at vertical position 1 of character 2 in the printing example of FIG. 1 will be printed. When the horizontal dot line at vertical position 1 is finished printing,
The printing paper is advanced to the horizontal dot row at vertical position 2. At this time, the vertical position control circuit 19 is incremented by 1, and the vertical position information r specifies vertical position 2. This horizontal dot row is printed in one direction during the return of the reciprocating motion of the printing hammer group. Therefore, the horizontal position information e of the horizontal position control circuit 7 is designated in the order of horizontal positions 6, 5, 4, 3, 2, and 1 according to the positions of the printing hammer group. From the dot pattern n selected in this way, the bit at vertical position 2 is selected by the data selector 18. When this output has a logical value of 1, the hammer drive signal q also has a logical value of 1, and printing is performed, as described above. At this time, the bits from horizontal positions 5 and 1 have a logical value of 1, so character 2 in the printing example in Figure 1
Two dots at vertical position 2 will be printed. Thereafter, in the same manner, vertical positions 3 to 7 are printed, and one line of printing is completed. After printing one line, the printing paper is fed to the vertical position 1 of the next line. In this way, characters such as letters, alphabets, numbers, symbols, and katakana can be printed. Next, the control device of the present invention used when printing figures and large characters will be explained with reference to FIGS. 3 and 4. When the printing device becomes able to receive print data from the host device 1, the data transfer start signal i becomes logical 1, and the flip-flop 9 is reset.
The data transfer start signal i is also sent to the host device 1, and the transfer of print data a from the host device 1 is the same as when printing characters. The print data a is 8 as shown in Tables 3 to 6.
A printed dot pattern consisting of bits. Print data a is written to PLB2 by the synchronization signal. Further, the adder 3 is cleared to zero before transferring one dot line of print data a, and sequentially adds and stores the print data a transferred thereafter. What is added is 6 bits from bit 1 to bit 6 in print data a. Print data a in FIG. 4 indicates a number whose logical value is 1, and the addition result is indicated as b. When the host device 1 finishes transferring the print data a for one dot line in this way, the host device 1 sets the one dot line data transfer end signal g to a logical value of 1, and
Notify the printer of the end of data transfer. When the printing device receives this signal, it ends the data reception cycle and shifts to the printing cycle. This signal is also input to the NAND gate 11 in the printing device. Also input to the NAND gate 11 is the result of comparison by the comparator 4 to determine whether the addition result b of the print data a for one dot line is greater than a predetermined value N. When the addition result b is larger than N, the over Nf becomes a logical value 1, and when it is smaller, it becomes a logical value 0.
It is. Furthermore, a plot mode signal h from the host device 1 indicating that the program is in the plot mode is also input with a logic value of 1. When the plot mode signal h has a logical value of 1 and the 1-dot row data transfer end signal g has a logical value,
If over Nf is logic 1, flip-flops 8 and 9 are set;
1 output terminal becomes logical value 1. When one output terminal of the flip-flop 9 has a logic value of 1, it means that the total number of printed dots of the received one-dot line of print data a is greater than N, and instructs to print in a round trip. When one output terminal of the flip-flop 8 has a logical value of 1, the odd numbered position 1 among the horizontal printing positions,
When the 0 output terminal of the flip-flop 8 has a logical value of 1, it enables printing at even positions 2, 4, and 6 among the horizontal printing positions. On the other hand, the horizontal position control circuit 7 corresponds to the position of the printing hammer group and instructs the horizontal position at which printing is performed.
Outputs horizontal position information e consisting of bits. When the least significant bit 2° of this horizontal position information e has a logical value of 0, it indicates an odd horizontal position, and when it has a logical value of 1, it indicates an even horizontal position. First, printing at odd-numbered positions will be explained with reference to FIGS. 3 and 5. Note that the symbols a to q in FIG.
They correspond to the symbols a to q in the figure. As mentioned earlier, since the 1 output terminals of flip-flops 8 and 9 both have a logic value of 1, the output of the AND gate 13 will have a logic value of 1 if the output of the inverter 10 is a logic value of 1, that is, at an odd horizontal position. become. When the 2° bit of the horizontal position information e has a logical value of 0, the output of the inverter 10 has a logical value of 1, the output of the AND gate 13 has a logical value of 1, and the output signal l of the OR gate 14 has a logical value of only that period. Becomes 1. This signal l is input to AND gate 15. The other input signal p of the AND gate 15 is
When the plot mode signal h has a logical value of 1, the ungate 22 opens its gate, so that the bit information corresponding to the horizontal position is obtained from the print data a stored in the PLB 2. That is, the 6-bit PLB data d output from the PLB 2 according to the instruction of the PLB address C is input to the data selector 6, and from among the 6 bits, the horizontal position control circuit 7
The bit information of the current horizontal position is selected based on the horizontal position information e which is the output of the signal m, and is output as a signal m. When this signal has a logic value of 1, the output of the AND gate 22 becomes a logic value of 1, and the OR gate 2
3, the hammer drive signal q is set to a logical value of 1, the printing hammer is driven, and dots are printed on the paper. To explain the operation in more detail, as shown in FIG. 5, when the horizontal position signal e is a certain value, for example 0, depending on the position of the printing hammer group, 132 signals from 0 to 131 of the PLB address c are 132 pieces of PLB data d from 0 to 131 are sequentially output in accordance with the address. These 132 PLB data d that are output sequentially
Among them, only the data at the horizontal position 0 is outputted from the data selector 6 as the print information signal n. When the horizontal position information e is 0 (odd number), the hammer drive enable signal has a logical value of 1, so the hammer drive signal q becomes a signal corresponding to the print information signal m. Hammer drive signal q is 132 of one horizontal position
For example, it corresponds to 132 PLB data d input to the system register (not shown).
When the data for the digits is complete, a signal is transmitted to the printing hammer to drive the printing hammer, and a predetermined dot is printed on the paper at the first dot printing position for each of the 132 digits. However, if the horizontal position information e is 1 (even number), the hammer drive enable signal l will have a logical value of 0, and no matter what value the print information signal m has, the hammer drive signal q will have a logical value of 0, and the printing hammer will It is not driven and no dots are printed. Similarly, when the horizontal position information e is 2 (odd number) or 4 (odd number), the hammer drive enable signal l has a logical value of 1, and the print information signal m is set as the hammer drive signal q, and the predetermined dots are placed at the third position. Alternatively, a predetermined dot is printed at the fifth dot printing position. When the horizontal position signal e is 3 (even number) or 5 (even number), the hammer drive signal q has a logical value of 0 and no dots are printed. In this way, during one-way movement of the printing hammer group, only odd-numbered horizontal positions are printed. When printing of one dot row at an odd numbered position is completed, the printing hammer group starts moving in the opposite direction. At this time, the odd-numbered position printing end signal j becomes a logical value of 0, and the flip-flop 8 is reset. During this period in which the direction of movement is reversed, normally the printing paper is advanced to the next dot print row, but when the flip-flop 9 is set, no advancement is performed. Now, the operation when the printing hammer group starts moving in the opposite direction will be explained with reference to FIG. The symbols a to q in FIG. 6 correspond to the symbols a to q in FIG. As mentioned above, the 1 output terminal of the flip-flop 8 has a logic value of 0, and the 0 output terminal has a logic value of 1. Therefore, the output of the AND gate 12 becomes a logical value 1 when the least significant bit 2° of the horizontal position information e is a logical value 1, that is, an even horizontal position. Therefore, the output signal l of the OR gate 14 has a logic value of 1 only during that period. This signal l is input to AND gate 15. The other input signal q of the AND gate 15 is bit information m of the current horizontal position from the print data a stored in the PLB 2 based on the horizontal position signal information e. This signal has a logic value of 1
Then, the output of the AND gate 15, the hammer drive signal q, becomes a logical value of 1, and the printing hammer is driven to print a dot on the paper. In this way, only even-numbered horizontal positions are printed during one-way movement of the printing hammer group. As mentioned above, when the number of dots printed in one dot line is larger than the predetermined value N, the one dot line is printed during the reciprocating movement of the printing hammer group, so even in the worst case, it is normal. The printing hammer and its driving circuit may be sufficient to print the characters. Therefore, the cooling device for preventing the heat generation of the coil of the printing hammer can also be made small, and the device can be downsized and manufactured at low cost. When the number of dots printed in one dot line is smaller than N, one dot line is printed in one way of the printing hammer group, that is, two dot lines are printed in one round trip of the printing hammer group, so the printing speed must be reduced. There isn't. According to the present invention, if the number of dots printed in one dot line is greater than a predetermined number,
Since one line of dots is printed in one round trip of the printing hammer, the number of dots printed one way can be reduced, and even under the most severe conditions, the normal printing hammer and its drive circuit can be used. Can be used. For this reason, there is no need to make the printing hammer and its drive circuit large in order to cope with worst-case printing, or to make the coil cooling device for the printing hammer large, so the printing device can be made smaller, lighter, and cheaper. can do.

[Brief explanation of drawings]

1 and 2 are front views showing an example of printing ordinary characters and figures in the plot mode, FIG. 3 is a block diagram showing an embodiment of the control device of the present invention, and FIGS. 4 to 6 are FIG. 4 is a timing chart for explaining the operation of FIG. 3; FIG. 4 is a data transfer period;
The figure shows an odd position printing period, and FIG. 6 shows an even position printing period. In the figure, 1 is a host device, 2 is a PLB, 3 is an adder, 4 is a comparator, 5 is a PLB address counter, 6 and 18 are data selectors, 7 is a horizontal position control circuit, 8 and 9 are flip-flops, 10, 1
6 and 20 are inverters, 11 is a NAND gate, 1
2, 13, 15, 21, 22 are AND gates, 1
4 and 23 are OR gates, 17 is a CG, and 19 is a vertical position control circuit.

Claims (1)

[Claims] 1. A plurality of printing hammers having dot printing elements are arranged side by side along the printing line, and these printing hammer groups are reciprocated in a direction across the printing paper,
In a dot printing device that drives a group of printing hammers to print during this reciprocating process, a printing device stores one dot line of printing dot data transferred from a host device that transmits data to be printed to the device. a data buffer; horizontal position indicating means for changing output values as the printing hammer group moves in the row direction and generating an output at a horizontal position corresponding to the moving position of the printing hammer group; and printing dot data from the printing data buffer. Of these, a selection means outputs print information at the horizontal position designated by the horizontal position instruction means, and a selection means that counts the number of print information to be printed in one dot print line before starting printing, and outputs a signal when a predetermined value is counted. a counting means for generating and receiving an output signal generated by the counting means;
control means for selecting printing information outputted from the selection means into information to be printed during the forward movement of the printing hammer group and information to be printed during the return movement;
When the counting means does not generate an output, two dot lines are printed in one reciprocation of the printing hammer group, and when the counting means generates an output, one dot line is printed in one reciprocation of the printing hammer group. 1. A control device for a dot printing device, characterized in that printing is performed according to the output of a dot printing device.