JPS6035687B2 - Print data control device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a control device for providing print information to a printer.

In a printing device that prints characters or figures indicated by a dot pattern, printing information is controlled as follows.

One method is to store print information using a code that indicates a character or figure, and when performing a printing operation, read the code, derive a dot pattern conversion table from the code, obtain the print information, and print. It is.

With this method, if the printing speed becomes long, it will not be possible to draw the conversion table in time. Therefore, it is conceivable that the code is converted into a dot pattern and the edited result is stored in a storage device in advance, and then sequentially read out and transferred to the printer. However, in a printer with a large number of dots per character, such as a kanji printer, the amount of information even for one page is enormous, and having that much storage device makes the device expensive.

In view of the above points, the present invention stores edited print information in an external large-capacity storage device such as a magnetic disk or magnetic drum, reads out portions of it into a small-capacity storage device, and transfers it to a printer. By doing so, the purpose is to supply print information at high speed and at a relatively low cost, and in particular, the purpose is to perform good transfer control of print information.

In the present invention, print information (hereinafter simply referred to as data) is converted from a character code into a dot pattern using a conversion table asynchronously with the printer, edited in units of one page, and stored in an external storage device. In addition, the printer is a so-called laser printer that scans a laser beam, forms a latent image according to data on a photosensitive drum, and prints on paper by development and transfer, or an electrostatic printer that has an electrostatic electrode. may be used. Now, in the method of storing data in an external storage device (hereinafter referred to as external memory), reading a certain amount of data from the external memory to a small capacity high-speed storage device (hereinafter referred to as memory), and transferring it from the memory to the printer, the following conditions are required. It is.

'1) The external memory must be faster than the printer in terms of transfer speed between the external memory and the printer.

■ The memory capacity must be large enough to allow data to be transferred to the printer without running out of data within the waiting time for reading data from external memory. [3- The memory requires at least two areas: one to store data being transferred to the printer, and one to store data transferred from external memory.

Then, the area where the transfer to the printer is finished is controlled to immediately import new data from the external memory. FIG. 1 is a conceptual diagram of print data transfer according to the present invention, where 1 is an external memory for storing edited data, 2 is an
3 indicates a printer.

Each area has a capacity equal to the size of the block transferred from external memory. Figure 2 shows data for one page, where L is the amount of data for one horizontal scan, M is the number of scan lines for one memory area, N is Mxn, and is the total scan line. Let the number be K.

The feature of the present invention is that a certain number of bytes of data starting from a specified area on the memory 2 are read from the memory according to the amount of data transferred in a specified horizontal scan, and then the data is read from the memory 2 in a specified number of bytes.

2 bits at a time as dot information to the printer device by a horizontal periodic signal of a constant period generated from the IJ printer device 3.
A known printing mechanism forms an electrostatic scanning image on the photosensitive drum, and at the same time, each time a certain data transfer is completed, the program is notified that the printer has used up a certain area on the memory 2. have means to do so. Transfer control from external memory 1 to memory 2 is realized by applying conventional technology. The second feature of the present invention is that the number of data transfers per horizontal scan (L) and the total number of scans (K) are set to arbitrary values by a program, and a means for interrupting every fixed number of scans (M) is provided. (N) A means is provided to return the memory address register to the starting address of the buffer area on the memory 2 after an interrupt, and the setting of the transfer amount can be made variable.

A third feature of the present invention is that the capacity of the data buffer for storing data read from the memory 2 is smaller than the amount of data required for one horizontal scan.

FIG. 3 shows an embodiment of the present invention.

Prior to the printing operation, the memory 2 is sent from the program processing device 5.
Enter the start address A of the data sought above in the address register 11, the number L of transfer bytes during one horizontal scanning transfer in the row byte register 2, and the number M of horizontal scanning transfers that partially generate an interrupt in the horizontal number count register 13. , the number of horizontal scans N for initializing the memory address is stored in the block count register 14, and the number of horizontal scans K for generating a full transfer end interrupt is stored in the row count register 5 for the data bus line 2.
Set through 1.

Thereafter, data transfer and printing operations are activated by a data transfer activation signal (not shown). Data transfer is first performed from external memory to memory 2.

The control is performed by the program processing device 5. The program processing device 5 is provided with flags corresponding to each of the above memory areas, and when it detects that the flag is "0", that is, the area is empty, it controls data transfer from the external memory 1 to the memory 2. . Such data loading follows a conventional control method and will not be described in detail here.
Next, the contents of the memory address counter 6 connected to the memory address register 11 are transferred to the memory address line 22 by the activation signal from the activation device from the program processing device.
Data of a predetermined data length (for example, 4 bytes) is read out from the data buffer area on the memory 2 onto the data read line 23 and stored in the buffer register 17.

Two shift registers 18a and 18b are connected to the lower part of the buffer register 17, for example, for loading one byte of data at a time and shifting it out to one bit.
A transfer clock is generated in the transfer clock control unit 101 by the data request line 24 from the transfer clock line 25, and binary data of 1 bit each is sent to the printer via the data line 26 as a print pattern. .
Every time 8 transfer clocks are generated, shift register 8
a, 18b are switched alternately, and while one shift register is shifting data out to the printer, the other shift register is loaded with one byte of data from buffer register 17 through byte line 27.

Each time the shift register is switched, the contents of the row output byte counter 19 are incremented by 11.

When the data transfer operation to the printer is performed in parallel and free space is created in the buffer register 7, the data on the memory is immediately input, and each time the data is input, the line input byte counter 31 is
14.

Row input byte counter 31, row output byte counter 19
The contents of the row byte register 12 and the comparator 51 are always
, 52. As a result of the comparison, the input byte counter 31 in the first row is detected as a match in the comparator 52 on the detection line 2.
When detected, even if the buffer register 17 becomes empty, control of reading data from the memory is inhibited by the memory control unit 102. Thereafter, after a period of time has elapsed, the row output byte counter 9 detects a match in the comparator 51, generates a signal on the detection line 29, recognizes that the transfer in one horizontal scan is completed, and transfers the transfer clock in the transfer clock control unit 101. Stop. At this time, at the end of the horizontal scan, the contents of the horizontal number counter 13a and the row count register 15 connected below the horizontal number count register 3 are decremented by 1 in response to the signal on the detection line 29.

0 detector 53 determines whether the content is zero as a result of -1.
If the content of the horizontal number counter 3a is zero, a signal is generated on the 0 detection line 42, and an interrupt control is performed on the program processing device because the number of data in one block of the data buffer area on the memory has been transferred. It is reported via the interrupt line 41 via the section 103. Block counter 4 connected to the lower part of block count register 14 at the same time
The contents of a are incremented by 1, and the contents of the horizontal number count register 3 are loaded into the horizontal number counter 13a to initialize it.
When the horizontal number counter 3a detects zero as many times as the value set in the block count register 4, the value of the block counter 4a is detected as zero by the 0 detector 54,
The memory controller 102 generates a signal on the 0 detection line 43, loads the initial value set in the memory address register 11 into the memory address counter 16, and controls the memory controller 102 to indicate the start address of the data buffer in the memory 2. be done. Now, when data for one horizontal scan is transferred from the memory, input of the data to the buffer register 17 is inhibited by recognizing that the row input byte counter value matches the constant value L by the comparator 52.

Data input is resumed after data for one horizontal scan is output to the printer 3, the contents of the horizontal scan counter 13a, flock counter 14a, and row count register 15 are updated, and then the contents of the row count register are detected to be 0. This is continued until the detector 55 detects zero on the 0 detection line 44. When the zero detector 55 detects that the contents of the row count register 15 are zero, it recognizes that the data transfer for one page has ended, and the interrupt control unit 103 generates a total transfer end interrupt signal on the interrupt request line 45. , informs the program processing device.

The method by which the program processing device identifies the end of transfer upon receiving the notification is an existing technology and will not be discussed here.

[Brief explanation of the drawing]

Fig. 1 is a schematic configuration diagram of the present invention, and Fig. 2 is a paper 1 of the present invention.
FIG. 3 is a diagram showing the amount of information per page, and FIG. 3 is a diagram showing the configuration of the present invention. 11...Memory address register, 12...Row byte register, 13...Horizontal number count register, 1
3a...Horizontal number counter, 14...Flock count register, 14a...Flock counter, 15...Line count register, 16...Memory address counter, 17...Buffer register , 18a...shift register, 18b...shift register, 19...
...Row output byte counter, 21...Data bus line,
22...Memory address line, 23...Data read line, 24...Data request line, 25...
Transfer clock line, 26...Data line, 27...
... Byte line, 28, 29 ... Match detection line, 31 ... Line input byte counter, 41 ...
...Partial transfer end interrupt line, 42...0 detection line (horizontal number counter), 43...0 detection line (block counter), 44...0 detection line (row counter) ),
51... Row output match detector, 52... Row input match detector, 53... Horizontal number counter zero detector, 54... Flock counter zero detection. vessel, 55
......Row counter zero detector, 101...
Transfer clock control unit, 102...memory control unit, 103...interrupt control unit. Oh figure 2 figure bottom

Claims (1)

[Claims] 1 Equipped with a large-capacity first memory for storing print data edited by converting characters and figures into dot patterns, and a small-capacity second memory, data is transferred from the first memory to the second memory in small units. , it was a device that reads data from the second memory while sequentially updating the address register and sends it to the printer.The second memory has multiple areas, and in response to a data request from the printer, data is read from the second memory and sent to the printer. means for starting the transfer of data to the print and stopping the transfer when the transfer of the amount of information for one horizontal scan is detected;
means for reporting to a control means every time the transfer of data corresponding to the capacity of the one area is detected; and a control means for causing the data for the one area to be transferred from the first memory to the second memory based on the report; and means for setting the address register to an initial value when the number of scanning lines equal to the capacity of the plurality of areas of a second memory is transferred.