JPS5932036A - Print controller - Google Patents

Abstract

PURPOSE:To improve the effective processing time of a CPU and at the same time to increase the buffer effective region of a picture element memory, by performing the space printing only with a shift of carriage without feeding the space data to a printing head. CONSTITUTION:A CPU1 feeds the print data to a head controller 4 in response to a print data request signal (g). While a memory 2 stores a working program and the print data of the CPU1. A motor control part 3 controls the paper feed as well as a carriage motor which feeds a print head 8, and a head control part 4 performs printing with the head 8 on the basis of the print data given from the CPU1. An interruption request for transmission of print data is not necessary to the CPU1 in a space section where the head 8 has no need for printing. Therefore, it is possible for the CPU1 to perform other processing. This device improves the system efficiency.

Description

[Detailed Description of the Invention] [Technical Field of the Invention] The present invention relates to a printing control device, and particularly to a central control unit (hereinafter referred to as
A print control device suitable for reducing the dedicated time required for print processing by a CPU (referred to as a CPU)? Regarding this.

[Technical background of the invention and its problems]

Generally, serial dot matrix printers are controlled by a dedicated microprocessor.
In recent years, the burden on microprocessors has increased as functions for increasing printing speeds and printing quality have increased. For example, while the carriage motor is operating and printing is being performed, services such as data transfer may be required, and it is necessary to deal with this by using interrupts, polling, or the like. For this reason, the CPU requires time for these processes and searches, and there is a limit to the improvement in processing speed.

On the other hand, in conventional printing control, for example,
As shown in the printing example in the explanatory diagram, a space section T81 consists of 82 spaces where no example is printed between characters.
), each space is treated as one character, so the gear ridge motor that sends the print head for printing accelerates as shown in the time chart in Figure 1 (0). The CPU performs similar printing processing operations for both character printing and space printing until the speed is decelerated after passing through a constant speed section during which a predetermined character string is printed. For this reason, the CPU has to send space data to the print head even in the space 8P section where the print head does not need to print, which is a big waste when considering the load on the CPU and processing time. .

[Purpose of the invention]

Therefore, the object of the present invention is to eliminate the drawbacks of the above-mentioned prior art and
In space printing, this is done by only sending the space data to the print head and only sending the carriage. This eliminates the need for the CPU to request space data, improves the CPU's effective processing time, and improves the pixel processing time. The present invention provides a print control device that makes it possible to expand the effective buffer area of memory.

[Summary of the invention]

In order to achieve the above object, the printing control device of the present invention includes a head control means for controlling a print head that performs printing, a first means for determining the printing period, and a central control device based on the output of the first means. a second means for generating an interrupt signal to request the control section to send print data to the head control section; and prohibiting an interrupt signal sent from the second means to the central control section in the space section. and the third means to do so.

[Embodiments of the invention]

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 2 is a block diagram of a print control device according to an embodiment of the present invention. The CPUI controls all parts related to print control, and has the function of sending print data to the head control section 4 based on the print data request signal g. On the other hand, the memory 2 stores CPUI operating programs and print data (-3).Moreover, the motor control section 3 controls the carriage motor (pulse motor, not shown) that sends the print head 8 and the paper feed. The head control section 4 has the function of causing the print head 8 to perform the necessary printing based on the print data from the CP'U 1.The counter 50 notifies all print starts from the head control section 4. Upon receiving the input of signal a,
The entire printing cycle required for printing consecutive characters is determined, and the corresponding key code is sent out. On the other hand, the counter 51 receives the signal bf from the programmable counter 50 and sends out a signal cf corresponding to the excitation time of the print head 8. Furthermore, the counter 52 sets a space section, and outputs a signal 6 tones representing the start of the space section and indicating the interval of space 1 after input of No. 1 d. The gate 6 has the function of sending an interrupt high signal g for a data request for printing to the CP 'U 1 based on the 4M'-'8'C from the counter 51, and the impark 7 has the function of sending an interrupt high signal g for a data request for printing to the CP 'U1 based on the 4M'-'8'C from the counter 51. The gate 6 inverts the signal e indicating the space section of and outputs it as a signal f.
It has the effect of giving

In this structure, the detailed TjD+ work will be shown in the third section.
This will be explained according to the time charts shown in FIGS. (a) to (b).

Incidentally, FIGS. 3(a) to 3(g) correspond to the waveforms of numbers a to g in the block diagram of FIG. 2, respectively.

At the start of printing, when a carriage motor start signal is given from the CPU to the motor control section 3, the print head 8 starts to feed, but when it reaches a constant speed, the head control section 4 sends a signal to start the carriage motor. signal a indicating
is sent. This signal a'fr is received by the counter 50.
starts periodic output of a time signal corresponding to the print cycle determined by the carriage speed and print interval. Four signals output in each print cycle are stored in a counter 51, and the counter 51 that receives all the signals counts the excitation time required for the print head 8 to print one character, and then
Signal Cf that is the basis of interrupt for data request to I
Send. Note that the head control unit 4 sends out a signal d when printing corresponding to a space, but at this point the counter 52 is preset by the CPU to the space interval, and the counter 52 continues to count up the signal C for this interval. The output signal e is set to low level. As a result, the signal f, which is the output of the inverter 7, becomes high level in the space section. On the other hand, when the head control unit 4 does not send out the signal d indicating the start of the space interval, the counter 52 maintains its output signal e at a high level, so that the output signal f of the inverter 7 is set at a low level.

Therefore, when printing characters other than spaces, the gate 6 sends the signal C from the counter 51 to the CPUI as the print data request interrupt signal g, and performs the interrupt operation required to print the necessary character, that is, the head control unit 4. The print data is transmitted to the target. On the other hand, in the space printing section, the counter 52 operates to prohibit the output of the print data request (g, g) from the gate 6, so an interrupt is generated to the CPUI to send the print data. figure,
Therefore, the print head 8 does not perform any printing in this space section, and only the carriage is moved by the space section.

In the case of +1" printing as shown in Fig. 2, C is used in the space section where the print head 8 does not need to perform printing operation.
Since there is no request to send print data to the PU, the CPU can perform other processing such as data transfer processing during this time, making it possible to improve system efficiency. On the other hand, since it is no longer necessary to store space characters, which were conventionally treated as one character's worth of data, in the buffer memory for art books, the efficiency of buffer memory usage increases, and high-quality printing that requires a large amount of memory space, such as It becomes possible to easily handle the printing of Kanji characters.

〔Effect of the invention〕

As described above, according to the present invention, in a space section in which no print data is required for printing, interrupts of character data requests to the CPU are prohibited and only the carriage is moved in a blank manner. , CI) TJ can perform other processing, thereby increasing the utilization efficiency of the CPU and providing a printing control device that is effective in increasing the speed of various processing.

[Brief explanation of drawings]

FIG. 1(B) is an explanatory diagram of a printing example, FIG. 1(B) is a time chart showing the speed of the carriage motor corresponding to the printing example in FIG. 1, and FIG. The block diagram of the control device and FIGS. 3(a) to 3(g) are time charts showing the operation of each item m of the 21st agent. 1... C1) U, 2... Memory section, 3... Morph control section, 4... Head control 131 (
, 50, 51, 52... programmable counter, 8
...Print head. 111 Applicant's Agent Ino Mata f+″f219

Claims (1)

[Claims] 1. Head control means for controlling the print head;
a first means for determining a printing cycle; a second means for generating an interrupt signal to request the central control section to send all print data to the head control section based on the output of the first means; second means for generating an interrupt signal to request an interrupt signal to be sent from the second means to the central control unit in the space interval; 'jlS is sent to an interrupt (, No. 4) The third means for inhibiting the print control device ftt 0 2, the third means is the print space section, the entire length is preset, and the print space is The printing control device according to claim 1, comprising a gate circuit controlled by a counter that operates from the start of the section.