JPS61225065A - Printing system of wire dot matrix printer - Google Patents

Abstract

PURPOSE:To reduce the frequency of interruption processing, by providing printing buffer memories in two stages. CONSTITUTION:A front stage buffer 3 is formed of a shift register capable of storing 48-bit data and, by the pulse synchronous to the timing of a printing timing control part 10, printing data for even number pins and odd number pins of stored printing data are alternately transmitted to odd number line and even number line post stage buffers 4, 5 in a 12-bit unit. Odd number line and even number line printing pins 8, 9 are alternately driven by odd number line and even number line drivers 6, 7. Because the transmission of printing data to the front stage buffer 3 is performed in 4 columns and a 48-bit unit, the interruption signal of the printing timing control part 10 may be generated every when the odd number line and even number line printing pins 8, 9 are driven 4 times in total. Because the frequency of the interruption signal comes to 1/4 of the driving timing of the printing pins and allowance is generated in the processing time of the printing timing control part 10, interruption processing from other I/O is enabled.

Description

DETAILED DESCRIPTION OF THE INVENTION <Industrial Application Field> The present invention relates to a printing method for a wire dot matrix printer, and particularly to a printing method when using two rows of staggered printer wires.

<Conventional technology> In kanji printers and letter quality printers, 2
Printers with rows and rows of printers are often used, and as the mechanical printing speed improves, it is desired to improve the overall printing speed by making electronic print data processing more efficient.

<Problems to be Solved by the Invention> Using hardware for data transfer such as a DMA method speeds up the print data transfer process, but on the other hand, the configuration becomes complicated and the cost increases. Therefore, print data is normally transferred using an interrupt signal from the print timing control section, but as mechanical printing speed improves, the timing of print data transfer becomes complicated, and in some cases, the print timing control section This results in an inconvenience that the printing speed decreases due to insufficient time margin.

In view of these drawbacks of the prior art, the main object of the present invention is to improve the transfer of print data and the timing of printing in a printing method that transfers print data using an interrupt signal from a print timing control section. It is an object of the present invention to provide an improved printing method for a wire dot matrix printer that can perform control in a timely manner, improve printing speed, and eliminate printing deviations due to variations in printing timing.

According to the present invention, an object of the present invention is to provide a printing method for a wire dot matrix printer having two rows of staggered printing pins. The print data transferred from the print data control unit in synchronization with
It has a front stage buffer capable of storing columns, and two rear stage buffers that store print data of two columns each so that the print data is transferred alternately from the front stage buffer according to printing timing, and printing from each of the rear stage buffers is provided. This is achieved by providing a printing method characterized by driving each pin according to data.

Effects> By providing the print data buffer memory in two stages as described above, the frequency of interrupt processing can be reduced, and the processing time of the print timing control section can be increased.

<Embodiments> Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings.

FIG. 1 shows a configuration for implementing the printing method according to the present invention using a one-step diagram. This embodiment relates to a configuration for controlling a 24-pin print head in a two-column staggered arrangement, and one column of print data corresponds to 12-bit data for driving even-numbered pins or odd-numbered pins.

The print data sent from the host CPU is stored line by line in the RAM 2 by the print data control unit 1. The print data control section 1 transfers print data of 4 columns, that is, 48 pits, to the pre-stage buffer 3 in response to an interrupt signal from the print timing control section 10. At this point, the print data will be transferred six times, each containing eight bits.

The pre-stage buffer 3 consists of a shift register capable of storing 48 bits of data. The print data stored in the front-stage buffer 3 is transferred to the rear-stage buffer for odd-numbered rows in units of 12 bits each for even-numbered pins and print data for odd-numbered pins in response to pulses synchronized with the print timing from the print timing control unit 10. 4 and post-stage buffer 5 for even columns
Transfer alternately. The print data taken into these rear-stage buffers 4.5 alternately drives odd-numbered column printing pins 8 and even-numbered column printing pins 9 via odd-numbered column drivers 6 and even-numbered column drivers 7, respectively.

FIG. 2 is a timing chart showing the timing of the main parts in the configuration shown in FIG.

The printing timing of the odd-numbered column printing pin 8 is synchronized with the rising edge of the pulse shown in (a), and the printing timing of the even-numbered column printing pin 9 is synchronized with the rise of the pulse shown in (b). It is synchronized with the same rising portion of a pulse having a phase difference of 180'' with respect to the printing timing.

The transfer of print data from the front stage buffer 3 to the rear stage buffer 4.5 is also performed in synchronization with these print timings.

Since the print data is transferred from the print data control section 1 to the pre-stage buffer 3 in units of 4 columns, that is, 48 bits, the interrupt signal from the print timing control section 12 is transmitted to the odd column printing pin 8 and the even column printing pin 9. It is sufficient that this occurs every time the is driven a total of four times.

Therefore, the frequency of the interrupt signal from the print timing control section 10 is 1/4 of the drive timing of the print pin, so the processing time of the print timing control section 10 can be spared, for example, for interrupt processing from other 110, etc. This makes it possible to eliminate printing deviations caused by variations in the time required to transfer print data, and improve the overall printing speed.

<Effects of the Invention> As described above, according to the present invention, it is possible to smoothly control print timing and transfer print data by simply using a buffer memory having a relatively simple configuration, thereby improving print quality and printing. The effect is extremely large because the speed can be improved.

[Brief explanation of drawings]

FIG. 1 is a block diagram showing the configuration of a printing system of a wire dot matrix printer based on the present invention. FIG. 2 is a timing chart showing the timing in the configuration of FIG. 1. 1...Print data control unit 2...RAM3...Pre-stage buffer 4...Post-stage buffer for odd-numbered columns 5...Post-stage buffer for even-numbered columns 6...Odd-numbered column driver 7...Even-numbered column driver 8・
・・Odd number row printing pin 9 ・Even number row printing pin 10 ・・
・Print timing control unit patent Applicant: NHK Spring Co., Ltd. Agent: Patent attorney: Yo Oshima - Figure 1

Claims (1)

[Claims] A printing method for a wire dot matrix printer that has two rows of staggered printing pins, with a pre-stage buffer that can store four columns of print data transferred from the print data control section in synchronization with an interrupt signal from the timing control section. and two post-stage buffers that store print data of two columns each so that the print data is transferred alternately from the pre-stage buffer according to the print timing, and each pin is driven according to the print data from each of the post-stage buffers. A printing method that is characterized by: