JP2650404B2 - Printing equipment - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a printing apparatus such as a laser printer, and more particularly to addressing control of a memory storing print data.

[Related Art] Conventionally, in a printing apparatus such as a laser printer, data such as characters and graphics are printed on both sides of a sheet.
Performing so-called double-sided printing is described in, for example,
It is already known as shown in JP 9354. By the way, when performing double-sided printing and printing of a plurality of pages as described above, the print data of a plurality of pages such as the two-sided pages is divided into a plurality of blocks, and the blocks are stored in blocks in a page memory area used as a print data buffer. Was. At this time, the absolute address at the head of each block is stored in a table, one packet is formed using the block and table for one page, and packets for a plurality of pages are formed in the same page memory. The control side takes out the print data in the packet and performs print control on both sides of the paper.

[Problems to be Solved by the Invention] However, in the above configuration, when printing a plurality of pages, after printing a single page, the printed packet is deleted in order to print the next page, the block is moved, and the memory map is moved. Is changed, the absolute address of the block changes by the moving amount, so that a process of changing the absolute address is required each time. Therefore, there is a problem that the processing speed is reduced. Also, in order to avoid the above problem, a page memory is circulated (for example, Japanese Patent Publication No. Sho 63-12).
290), it is necessary to provide a table for storing the start address of each packet,
Had to use extra memory.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-described problem, and there is provided a printing apparatus which starts printing after storing print data of a plurality of pages in a memory when performing double-sided printing or multiple page printing. Even if the memory map is changed by moving the block, the printing process is continued without changing the address stored in the table each time, thereby reducing the data processing time for printing. It is an object of the present invention to provide a double-sided printing apparatus as described above.

[Means for Solving the Problems] In order to achieve the above object, the present invention provides a printing unit for printing on paper, and a page for dividing print data in page units output to the printing unit and storing a plurality of pages. A double-sided printing apparatus comprising: a memory; and a control unit that addresses a block formed by the division to the page memory in page units to form a packet and outputs the packet to a printing unit. Is formed, processing means for processing the relative address at the head of the block based on the head address of each packet and the head address of each block, and the relative address subjected to the table processing and a predetermined absolute address, An arithmetic unit for calculating an absolute address is provided, and printout is performed based on the calculated absolute address. It is like that.

[Operation] According to this configuration, even after the block is moved, the calculating means calculates the absolute address of the head of the block based on the relative address of the head of each block stored in the table. The printing operation is continued based on the absolute address.

[Embodiment] FIG. 1 shows an overall configuration of a double-sided recording apparatus according to an embodiment of the present invention.

In this embodiment, a laser printer is used.
A laser / scanner unit 2, an image recording process device 3, a fixing device 4, and the like are provided. The process device 3 includes a photosensitive drum 5, a main charger 6, a developing device 7, a transfer charger (transfer unit) 8,
It is composed of a separator 9 and the like. The laser / scanner section 2 converts a light image of a laser beam for recording data such as characters and graphics into a photosensitive drum 5 through a reflection mirror 10.
To form a latent image on the photosensitive drum 5, develop the latent image with a developing device 7, and transfer the latent image to a sheet with a transfer charger 8.

As for the paper transport system, two paper feed cassettes 12a and 12b each containing a paper 11 are mounted on one side of the main body 1, and the paper feed rollers 13a and 13b and the registration rollers 14
1 is conveyed to the transfer section 8, and after transfer and separation, the transfer guide section 1
The sheet is conveyed to the fixing device 4 through 5. Further, transport path switching levers 16 and 17 are disposed downstream of the fixing device 4.
The transport path is switched by a switching lever 16 between a face-down tray 18 provided on the upper surface of the main body 1 and a face-up tray 19 or a reversing tray 20 provided on the other side of the main body 1. On the other hand, the switching lever 17 is used to switch between the face-up tray 19 and the reversing tray 20 on the latter side.

Further, a reversing roller 21, a reversing conveyance path 22, a skew feeding roller 23, and a reversing paper tray 24 are provided as a device for reversing and conveying the paper on the reversing tray 20. A re-feed roller 25 for re-feeding paper is provided upstream of the roller 14. Further, a discharge roller 27 is provided in the transport path 26 facing the face-down tray 18.

In FIG. 1, a solid arrow indicates a paper transport route during the previous printing in the duplex printing mode, and a broken arrow indicates a paper transport route during the inverted printing.

FIG. 2 shows a block configuration of a printing control device for controlling a printing mechanism (engine) mainly including the laser / scanner unit 2.

The control device receives print data (hereinafter referred to as page data) for each page from an external device 40 such as a host computer via an interface 41, and a CPU 51 for controlling the entire device, and a page data and the like. A RAM 52 for storing, a video RAM 53 for expanding page data as image data, a ROM 54 for storing an operation program of the apparatus, a character generator, and the like, and a printing including the laser / scanner unit 2, the image recording process apparatus 3, and the like. It is composed of a mechanism (engine) 56 and the like.

The RAM 52 stores a reception buffer 52a for temporarily storing data sent from the external device 40, and a page data stored in the reception buffer 52a as shown in FIG. As shown in FIG. 4, the page data is developed into a format having position data indicating the recording position on the paper surface, and a page memory 52b for storing blocks for a plurality of pages, and a page memory 52b for a front page (odd page). Is set when the page data of is stored in the page memory 52b,
A front page data flag that is reset when the data is printed, and a back page that is set when page data for the back page (even number page) is stored in the page memory 52b and reset when the data is printed It comprises a working memory 52c for storing data flags and the like.

Next, the printing operation of the printing control device configured as described above will be described with reference to FIG. 5, FIG. 6, and FIG.

The page data is transferred from the reception buffer 52a to the page memory 52b.
As described above, the page data for one page of the sheet is divided into blocks in the order of input, and is developed into a format having position data indicating the recording position on the sheet surface. Then, as shown in FIG. 5, the head address of the print data of each block is stored in the address table as an absolute address (l) from the LSB (for example, address 0).
Then, one packet is constituted by the block for one page and the address table, and the memory size information of the packet is also stored in the address table.
To expand.

In the first page packet of FIG. 5, the block print data is stored in the order of the fourth, third, first, second, and fifth blocks. Regardless of the printing order, receive buffer
In the case where the address is input to the address 52a, the address table stores address information for performing bit development to the video RAM 53 in order from the print data of the first block.

Next, when printing the page data, from the memory size of each packet stored in each address table,
The absolute address (m) at the beginning of each packet is calculated, and the absolute address (m) at the beginning of each packet is calculated from the absolute address (m) and the absolute address (l) indicating the beginning of each block stored in the address table. The relative address (n) at the head of each block based on (m) is, for example,
It is obtained by n = ml, and as shown in FIG. 6, it is stored by replacing the absolute address (l) stored in each address table.

Thereafter, each packet of the first page and the second page is printed by the printing mechanism unit 56, the print data of the packet is deleted from the page memory 52b, and the packets of the third and subsequent pages are printed.

In this printing operation, after printing the first page and the second page, both packets are deleted by performing block movement of the data of the third and subsequent pages and overwriting the data of the first and second pages. At this time, the head of the packet on the third page is set to the highest address (MSB). Further, in order to develop and print as image data in block units, the absolute address (l) of each block after the third page on the page memory 52b is calculated by using the relative address (n).

The start address (m) of the third page packet from the highest address (absolute address) is calculated by adding the packet sizes stored in the tables of the first page packet and the second page packet. . Next, the relative address (n) of the desired block is obtained from the address table of the packet on the third page, and l = m−
The absolute address of the desired block is calculated from n.

To delete each packet on the first page and the second page, the total size to be deleted is obtained by adding the packet size stored in each table, and the block is moved by this size. (See FIG. 7).

Further, the operation of the control device will be described with reference to the flowchart of FIG. 8 showing the operation procedure.

The CPU 51 temporarily stores data (code) sent from the external device 40 such as a host computer in the reception buffer 52a via the interface 41, extracts the data from the reception buffer 52a (# 1), and prints the data. It is checked whether an emission code exists (# 2). If it does not exist, the data is divided into blocks as page data, the absolute address in the page memory area at the head of each block is stored in an address table, and a packet consisting of each block and table is stored for each page. It is formed and stored in the page memory (# 3, # 4). Then, returning to # 1, the same operation is repeated.

On the other hand, if it is determined in # 2 that the print ejection code exists, the absolute address in the page memory area at the head of each block stored in the address table is changed to a relative address (n) based on the head address of the packet. Change and store in the table (# 5). Further, the memory size of the packet is also stored in the table, and the registration of one packet in the page memory 52b is completed (# 6, # 7).

Next, it is checked whether the number of currently registered packets is 2 or more, that is, whether both the front page data flag and the back page data flag are set (# 8). If not, the process returns to # 1. The same operation is repeated until the next packet is registered. Also, 2
If so, the first packet is printed, and it is checked whether the printing of the second packet has been completed, that is, whether the back page data flag has been reset (# 9, # 1).
0). If the printing has not been completed, the process returns to step # 9, and waits for the printing of the second packet to be completed.

If it is determined that printing of two packets has been completed in # 10,
The two packets for which printing has been completed are deleted from the page memory 52b (# 11), the process returns to # 1, and the same operation is repeated.

Next, the printing operation of this apparatus, in particular, the operation (# 11) of deleting the packet from the page memory 52b will be described with reference to the flowchart of FIG.

If it is determined at # 10 in FIG. 8 that both the front page data flag and the back page data flag have been reset, the page data for the two pages is stored in the page memory 52b.
Go to remove from.

First, the memory size to be deleted is determined by adding the memory size of both pages from the memory size of each packet stored in the table of each packet (# 21).

Next, the head address of the packet of the next page is calculated from the memory size of each packet stored in the table of each packet, and the head address at which the block is moved is calculated (# 22).

Further, from the memory size of each packet stored in the table of each packet, the total number of packet sizes from the next page to the nth page stored in the page memory 52b is calculated, and the block movement amount is calculated. (#
twenty three).

Then, the block size is moved by the memory size from the block movement start address obtained in # 22 to the block movement amount calculated in # 23 by the memory size to be deleted calculated in # 21, and the next page At the top is the highest address (# 24). As a result, both packets of both printed pages are deleted.

If it is determined in step # 10 that both of the pages have not been reset, there is page data that has not been printed yet, so that the deletion routine is not entered.

In this way, even when data is moved from block to block, the absolute address of an arbitrary block can be calculated from the memory size of the packet and the relative address of the block.

[Effects of the Invention] As described above, according to the present invention, in a printing apparatus that performs page printing after storing print data to be printed and recorded on paper in units of blocks in a memory, the position of the block in the memory is represented by a relative address. By storing the data in the table, the absolute address of an arbitrary block can be calculated by calculation even if the position of the block is moved. Therefore, the address stored in the table is updated each time. Such a table operation is omitted, and the speed of the printing operation can be increased.

[Brief description of the drawings]

FIG. 1 is an overall configuration diagram of a two-sided printing apparatus according to an embodiment of the present invention, FIG. 2 is a block configuration diagram of a printing control device of the same device, FIG. FIG. 5 is a schematic configuration diagram showing one form of print data, FIG. 5 is a memory map of a page memory, FIG. 6 is a schematic configuration diagram showing an address table of the page memory, and FIG. 7 is a schematic diagram showing packet deletion in the page memory. FIG. 8 is a flowchart showing the operation procedure of the print control apparatus, and FIG. 9 is a flowchart showing the packet deletion. 3. Image recording process device, 40 Host computer, 41 Interface, 51 CPU, 52a Receive buffer, 52b Page memory, 53 Video RAM, 54
... ROM, 56 ... Printing mechanism.

Continuation of the front page (72) Inventor Usami Moto 9-35 Hottadori, Mizuho-ku, Nagoya City, Aichi Prefecture Inside Brother Industries, Ltd. (72) Inventor Kiyoshi Takahashi 9-35, Hotitadori, Mizuho-ku, Nagoya City, Aichi Prefecture Brother (56) References JP-A-63-246263 (JP, A) JP-A-62-274440 (JP, A) JP-A-63-730 (JP, A) JP-A-63-80339 (JP, A) JP-A-64-4845 (JP, A) JP-A-61-220880 (JP, A) JP-A-59-172188 (JP, A) JP-A-57-55581 (JP, A) 63-276627 (JP, A)

Claims (1)

(57) [Claims] 1. A printing means for printing on paper, a page memory for dividing print data in page units output to the printing means and storing a plurality of pages, and a block formed by this division in page units. In a printing apparatus, comprising: a control unit for addressing a page memory to form a packet and outputting the packet to the printing unit, wherein the control unit, when forming the packet, includes a start address of each packet and each Processing means for table processing the relative address at the head of the block based on the head address of the block; and calculating means for calculating the absolute address of the block based on the table-processed relative address and a predetermined absolute address. A printing apparatus for printing out based on the absolute address.