JPS6353053A - Printing apparatus - Google Patents

Abstract

PURPOSE:To easily perform high density printing output with respect to different printing patterns at a high speed and to also simplify control, by holding parallel printing data and reading said data to convert the same to serial data magnified at a predetermined magnification. CONSTITUTION:MPU 100 instructs a latch control circuit 2 to select one of latches A-H and writes printing data in the latch selected. At this time, the printing data outputted to data signals D0-D7 from MPU 100 is subjected to the MSB and LSB reversal processing due to a send-out reversal circuit and the data reversal processing due to a data reversal circuit to be written in the latch. MPU 100 starts an output control circuit 12 in order to read said data from output circuits A-H to output a serial output clock signal CKO and a serial output enable signal DFE. By this method, serial data are outputted to a printing head driving part 600 at a double magnification. Therefore, all of bits are subjected to printing output to become easy to look and the load to MPU 100 is not increased to make it possible to increase speed and to enhance density.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a printing device, and particularly to a printing device that prints out a desired pattern in a dot matrix. j It is related to B.

[Prior Art] In recent years, as the functions of printing and recording devices (hereinafter referred to as printers) have improved, there has been a particular trend toward higher speeds and higher resolutions.

Many printers are equipped with a microprocessor unit (hereinafter referred to as
Various controls were carried out using an MPU (called an MPU), and processing of print data was also carried out under arithmetic control using software. Therefore, in order to meet the demands for higher speed and higher resolution, it is necessary to use a high-speed and highly functional MPU.

Under these circumstances, some recent dot matrix type high-speed, high-resolution printers are now available with two printing modes: a draft printing mode and a fair copy printing mode. In this type of printer, high resolution is not required in the normal draft printing mode, and high speed is primarily required. High resolution is required only in the fair print mode.

In order to support these two printing modes, for example, two character generators that generate two types of printing patterns are provided, one of which is selected depending on the printing mode, and a desired pattern is generated. A method that includes only a means for generating character data for printing (data for fine print), and when in draft print mode, processes the character data for normal printing (data for fine print) by a program to create print data for draft. Either method was used.

In this method, for example, character data for normal printing is 10
In the case of a dot matrix of
It represented a XIO, or 5 x 10 dot pattern.

[Problems to be Solved by the Invention] In the above two methods, the method including two print pattern generating means requires a complicated configuration, and when only one pattern generating means is provided, pattern conversion is required in the MPU. The processing alone took a lot of time. Furthermore, the printed pattern was also difficult to see.

Furthermore, since these processes were performed by calculation control according to a program, it took a lot of processing time, and the MPU had to be complicated and expensive to perform high-speed processing, which caused problems in achieving high-speed printing. there were.

[Means for Solving the Problems] The present invention has been made for the purpose of solving the problems of the above-mentioned prior art, and includes the following configuration as a means for solving the problems.

That is, a holding means for holding parallel print data, a reading means for reading out the parallel print data held by the holding means, and converting the parallel print data read by the reading means into serial data enlarged by a predetermined magnification and outputting the same. and output means.

[Operation] In the above configuration, each process is executed in real time,
Parallel print data is converted to serial data while being enlarged at a desired enlargement rate and output.

[Example] Hereinafter, an example according to the present invention will be described in detail with reference to the drawings.

FIG. 1 is a schematic block diagram of an embodiment according to the present invention, in which reference numeral 100 indicates a central processing unit (100) that controls the entire apparatus according to the control procedure stored in the built-in ROM10I.
(hereinafter referred to as rMPUJ); 200 is a data conversion unit that converts print data and outputs it to print heads 610 to 640 according to output data and control signals from MPU 100;
For example, 00 is an input/output interface that controls the interface with an external device that outputs print data, 400 is a print buffer that holds print data sent from the external device via the human output interface 300, and 500 is a conveyor for transporting recording paper. The recording paper transport unit 600 to be controlled moves the print head 610 according to the print data from the data conversion unit 200.
~640 and print heads 610-640.
8! I] Print head drive unit, 61o, which performs control.

620, 630, 640 are print heads 0-3.

Details of the data converter 200 are shown in FIG. 1 in Figure 2
2 is an input buffer that also serves as an interface for each signal from the MPU 100, 2 is a latch control circuit for distributing print data placed on DO to D7, which are data signals from the MPU 100, to latch A4 to latch H1l, and 3 is an output control circuit. 12 is a trigger circuit that activates, 4 to 11 are latches ANH that latch the parallel print data sent from the large power buffer 1 via the sending inversion circuit 25 and the data inversion circuit 26, and 12 are latches A to H (4 ~11
), the output circuit control circuit controls the output of the output circuits A to H (13 to 20) that take in the parallel print data latched to the output circuit and serially output the data, and 13 to 20 are the output circuits A-
H, takes in parallel data from latches A-H (4 to 11), converts it to serial data, and outputs it.

21 is a serial buffer that temporarily holds serial data from output circuits A to H (13 to 20); 22 is a timing at which the data held in the serial buffer 21 is taken into the print head drive unit 600 under the control of the output circuit control circuit 12; a synchronous buffer that outputs a synchronous timing signal,
23 is a command control circuit that controls the command register 24; 24 is a command register that outputs control commands to the sending inversion circuit 25, data inversion circuit 26, variable circuit 27, etc.;
MSB and LS of print data sent from PU100
A transmission inversion circuit 26 controls the inversion/non-inversion of B, and a transmission inversion circuit 26 controls the transmission inversion circuit 25 according to instructions from the command register 24.
This is a data inversion circuit that controls inversion/non-inversion of "0" and "1" print data.

A specific circuit diagram of the data conversion section 200 having the above configuration is shown in FIG. Components corresponding to the block diagram in FIG. 2 are indicated by the same numbers.

In FIG. 3, the latch control circuit 2, trigger circuit 3, command control circuit 23, etc. are, for example, 74LS13 manufactured by TI.
8, latches A to H (4 to 11) are 74 manufactured by TI.
By LS374, output circuit A-H (13-20) is T
It is preferable to use 74LS151 manufactured by Company I.

The output circuit control circuit 12 outputs a serial output enable signal DTE from the output circuits A to H (13 to 20) of the print head drive circuit 600 and a serial output clock signal CKO indicating data capture timing. Also,
It outputs a Co signal which is a timing signal for changing the serial output of output circuits A-H (13 to 20). This Co signal is converted into a CKO signal 2 by a 4-bit binary counter 27.
As a result, output circuits A to H
The serial output from (13 to 20) is magnified twice and taken into the print head drive unit 600.

A detailed circuit diagram of the sending inversion circuit 25 shown in FIGS. 2 and 3 is shown in FIG.

Depending on the output inversion signal (CMO in Figure 3), which is a control signal from the command register 24, the manually inputted data signals of IO to F can be output as they are as QO to Q7, or the MSB and LSB of the data can be inverted and the data can be output as IO to F. ~F Q7~
You can select whether to convert it to QO and output it.

A detailed circuit diagram of the data inversion circuit 26 shown in FIGS. 2 and 3 is shown in FIG.

As shown in the figure, the output data signals IO to I from the output inversion circuit 25 are manually input by the data inversion signal (CMI in FIG. 3), which is a control signal from the command register 24.
7 as is as QO~Q7, or IO
~You can select whether to output it as F.

The operation of this embodiment having the above configuration will be described below.

Prior to sending the print data, the MPU 100 sends the CS- signal, AO signal to A3 signal, and W signal via the large-power buffer 12.
R-signal and data signal DO (g to D7
The following instruction values are set in the command register 24 by the signal.゛■MSB by sending rotation circuit 25
, Setting of LSB inversion/non-inversion, ■ Setting of “0” and “1” inversion/non-inversion by data inversion circuit 26.

Next, the latch control circuit 2 is instructed to select one of the latches A-H (4 to 11) via the input buffer 1, and the print data is output to the data signals DO to D7, and the CS- signal and the AO ~3 and WR- signals write to the selected latch. At this time, the MPU 100 outputs the data signal DO~
The print data output to D7 is subjected to MSB and LSB inversion processing by the sending inversion circuit 25, data inversion processing by the data inversion circuit 26, etc. according to the setting value set in advance in the command register 24, and this processed data is latched. will be written in.

This writing is performed in order from latch A4 to latch B5...latch H1l, and if necessary, write to command register 2.
The setting value for 4 is also changed. In addition, latches A-H (4~
11) can be freely rewritten.

In this embodiment, the latch has four serial output systems as shown in the figure, and each system has a configuration of 8 bits x 2.

The MPU 100 writes the converted data to the latches A to H (4 to 11) in order, and then the CS
- signal, AO-A3 signal, and RD- signal, the trigger circuit 3 outputs a serial output start signal and starts the output control circuit 12. As a result, the output circuit control circuit 12 performs eight lines of operation thereafter, and the output circuit control circuit 12 starts outputting the serial output clock signal CKO and the serial output enable signal DTE. As a result, the image is output to the print head drive section 600 via the serial buffer 21 at a double magnification rate under the control described above.

When all the print data written to each latch as described above is sent out, the output circuit control circuit 12 outputs each output signal (CKO
, DTE, 500-3) and enters a standby state again in preparation for an activation instruction from the trigger circuit 3.

The enlargement process by the variable circuit 27 of this embodiment is, for example, by converting 8 bits x 2 = 16 bits configuration data to 2 times and converting it into 3
Although the data is converted into 2-bit data and output, the number of data to be enlarged and the enlargement magnification are not limited to this. It is only necessary to change the count-up clock from the counter 27.

Further, in this embodiment, the operation is stopped after serial output of all data, but the operation may be stopped in the middle of output. In this embodiment, it is also possible to stop the process midway using the RES signal.

Note that the number and configuration of each signal such as the number of data, number of addresses, etc. in this embodiment is not limited to this explanation.

As explained above, according to this embodiment, conventionally MPtJl
By software calculation based on program control of oo, MSB, LSB inversion conversion processing of print data, "O",
All of the "1" inverse conversion processing can now be done in hardware, reducing the load on the MPU 100 and significantly reducing processing time, making it possible to handle higher speeds and higher densities. .

In addition, the conversion from normal print data to draft print data was done by deleting the print bits that make up the print data, which was very quick, but with the automatic enlargement process, all the bits within the character size are printed out, which is very This makes it easier to see, and this also does not increase the load on the MPU 100 and does not impede higher speed and higher density.

Further, by forming the above configuration into a gate array, it is possible to provide a small and inexpensive device.

[Effects of the Invention] As described above, according to the present invention, high-speed, high-density printing output can be easily performed, and control can also be made simple.

[Brief explanation of the drawing]

1 is a schematic block diagram of an embodiment according to the present invention, FIG. 2 is a detailed block diagram of the data conversion section shown in FIG. 1, and FIG. 3 is a detailed circuit diagram of the data conversion section shown in FIG. 2. 4 is a detailed circuit diagram of the sending inversion circuit shown in FIG. 2, and FIG. 5 is a detailed circuit diagram of the data inversion circuit shown in FIG. 2. In the figure, 1... input buffer, 2... latch control circuit, 3... trigger circuit, 4-11... latch, 12...
...Output circuit control circuit, 13-20...Output circuit, 2
DESCRIPTION OF SYMBOLS 1... Serial buffer, 23... Command control circuit, 24... Command register, 25... Sending inversion circuit, 26... Data inversion circuit, 27... Variable circuit, l00-MPU, 101・ROM, 200... Data converter, 300... Input/output interface, 400
... Print buffer, 500 ... Recording paper forging section, 6
00... Print head drive section, 610-640... Print head.

Claims (1)

[Claims] a holding means for holding parallel print data to be printed out;
The present invention is characterized by comprising a reading means for reading out the parallel print data held by the holding means, and an output means for converting the parallel print data read by the reading means into serial data enlarged by a predetermined magnification and outputting the same. Printing device.