JPH02233277A - printing device - Google Patents

Abstract

PURPOSE:To accelerate a printing operation by storing a position on a memory of a block with a relative address in a table, and calculating the absolute address of an arbitrary block by a calculation even if the position of the block is moved. CONSTITUTION:When page data from a reception buffer is stored in a page memory, the page data of one page of a sheet are divided in an inputting order into blocks, and developed in a format having position data indicating a recording position on a sheet surface. The address of a head of printing data of each block is stored in an address table as absolute address (l) from a LSB. Then, when the page data are printed, the absolute address (m) of a head of each packet is calculated from the memory size of each packet, a relative address (n) of a head of each block is obtained, for example, in case of n=m-l with the address (m) as a reference, and substituted for the address (l) stored in each address table to be stored.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a printing device such as a laser printer, and in particular,
This invention relates to addressing control of a memory that stores print data.

[Prior Art] Conventionally, so-called screen printing, in which data such as characters and graphics are printed on both the front and back sides of a sheet of paper in a printing device such as a laser printer, has been described, for example, in Japanese Unexamined Patent Publication No. 59-1.
This is already known as shown in Japanese Patent No. 79354. By the way, when double-sided printing and printing of multiple pages are performed in this manner, the print data for the double-sided pages is divided into multiple blocks and stored in units of blocks in a page memory area used as a print data buffer.

At this time, the absolute address of the beginning of each block is stored in a table, one page of blocks and the table form one packet, multiple pages are formed in bucket 1 in the same page memory, and then printed. The control side of the device extracts the print data in the packet and controls printing on both sides of the paper.

[Problems to be Solved by the Invention] However, in the above configuration, when printing multiple pages, after printing a single page, the printed packet is deleted and blocks are moved in order to print the next page. When the memory map is changed, the absolute address of the block changes by the amount of movement, so it is necessary to change the absolute address each time. Therefore, there was a problem that the processing speed decreased. In addition, in an attempt to avoid the above problems, page memory was changed to circular memory (for example,
2290), it is necessary to provide a table for storing the start address of each packet, which requires additional memory.

The present invention has been made to solve the above-mentioned problems, and is provided in a double-sided printing device that stores print data of multiple pages in memory before starting printing when performing double-sided printing. Even if the memory map changes by performing a process, the printing process continues sequentially without changing the addresses stored in the table each time, thereby reducing the data processing time for printing. The purpose of the present invention is to provide a double-sided printing device.

[Means for Solving the Problems] In order to achieve the above object, the present invention has a printing device that prints on both sides of paper, and a device that divides print data in units of pages outputted to the printing device and stores a plurality of pages of print data. In a double-sided printing apparatus, the control means includes a page memory that addresses blocks formed by the division into the page memory page by page to form a packet, and outputs the packet to a printing means. , when forming a packet, a processing means for table-processing the relative address of the start of the block using the start address of each packet and the start address of each block, and the table-processed relative address and a predetermined absolute address, It is equipped with arithmetic means for calculating the absolute address of a block, and prints out based on the calculated absolute address.

[Operation] According to this configuration, even after block movement, the calculation means calculates the absolute address of the beginning of each block based on the relative address of the beginning of each block stored in the table, and the control means calculates the absolute address of the beginning of each block. The printing operation continues based on this absolute address.

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

This embodiment is a laser printer, in which a main body 1 is provided with a laser/scanner unit 2, an image recording process device 3, a fixing device 4, and the like.
, a main charger 6, a developer 7, a transfer charger (transfer section) 8, a separator 9, and the like. Laser/scanner section 2
The optical image formed by the laser beam of recorded data such as characters and graphics is transmitted to the photosensitive drum 5 via a reflecting mirror 10.
A latent image is formed on the photosensitive drum 5, this latent image is developed by the developing device 7, and further transferred to the paper by the transfer charger 8.

Regarding the paper conveyance system, two paper feed cassettes 12a and 12b containing paper 11 are installed on one side of the main body 1, and the paper 11 is transferred to the transfer section by paper feed rollers 3a and 13b and registration rollers 4. After being transferred and separated, the image is transported to the fixing device 4 via the transport guide section 15. Furthermore, a transport path switching lever 1 is provided on the downstream side of the fixing device 4.
6.17 is arranged, and the conveyance path is controlled by the switching lever 16.
The face town tray 18 side provided on the top surface of the main body 1,
It can be switched to either the face-up tray 19 or the reversing tray 20 provided on the other side of the main body 1. On the other hand,
The face-up tray 1 on the latter side is switched by the switching lever 17.
or the reversing tray 20.

Furthermore, as a device for reversing and conveying the paper on the reversing tray 20, a reversing roller 21, a reversing conveyance path 22, an oblique feed roller 23,
and an inverted paper tray 24 are provided, and a paper refeed roller 25 for refeeding the paper on the inverted paper tray 24 to the upstream side of the registration roller 4 is also provided. Also, conveyance route 26 heading towards Fusenis Town 1/Rei 18
A paper ejection roller 27 is provided.

In FIG. 1, solid line arrows indicate the transport route of the paper during previous printing in the double-sided printing mode, and dashed line arrows indicate the transport route of the paper during printing after reversal.

FIG. 2 shows a block configuration of a printing control device that controls a printing mechanism section (engine) mainly including the laser/scanner section 2. As shown in FIG.

This control device receives page-by-page print data (hereinafter referred to as page data) from an external device 40 such as a host computer via an interface 41, and a CPU 51 that controls the entire device, page data, etc. a video RAM 53 that is expanded as page data or image data, a ROM 54 that stores the device's operation program, character generator, etc., the laser/scanner section 2, and the image recording process device 3. It is composed of a printing mechanism section (engine) 56 and the like.

The RAM 52 also includes a receive buffer 52a that temporarily stores data sent from the external device 40, and page data stored in the receive buffer 52a in units of blocks, as shown in FIG. Divide into 4th
As shown in the figure, there is a page memory 52b that is expanded into a format with position data indicating the recording position on the paper surface and stores blocks for multiple pages, and a front page (odd numbered page).
A front page data flag that is set when the same page data is stored in the page memory 52b and reset when the same data is printed, and a back page (even numbered page)
A working memory 5 that stores back page data flags etc. that are set when page data for 10 minutes are recorded in the page memory 52b and reset when the same data is printed.
It consists of 2c etc.

Next, the printing operation of the print control device configured as described above will be explained with reference to FIGS. 5, 6, and 7.

The page data is transferred from the reception buffer 52a to the page memory 5.
2b, as described above, the page data for one page of paper is divided into blocks in the order of input, and expanded into a format having position data indicating the recording position on the paper surface. Then, as shown in FIG. 5, the first address of the print data of each block is stored in the address table as an absolute address (j) starting from the LSB (for example, address 0). Then, one packet is made up of one page's worth of blocks and an address table, and the memory size information of the packet is also stored in the address table and expanded in the page memory 52b.

In addition, in the first page packet of FIG. 5, does this indicate that the block print data is stored in the order of the 4th, 3rd, 1st, 2nd, and 5th blocks? Is this data? Receive buffer 5 in the above order regardless of the order of
2a, the address table stores address information for sequentially expanding bits into the video RAM 53 starting from the first block of print data.

Next, when printing page data, the absolute address (m) of the beginning of each packet is calculated from the memory size of each packet stored in each address table, and this absolute address < m) and the address table From the absolute address (!J) indicating the beginning of each block stored in
=m-1, and is stored in place of the absolute address ('') stored in each address table, as shown in FIG.

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

In this printing operation, after printing the first and second pages, blocks of data from the third page onward are moved.
Both packets are deleted by overwriting the data on the first and second pages.

At this time, the predecessor of the third page packet is set to the top address (MSB>). Also, in order to expand and print as image data in blocks, the page memory of each block from the third page onward is The absolute address ('') on 52b is calculated using the relative address (n).

By adding each packet size stored in each table of the packet on the first page and the packet on the second page, calculate the start address of the packet on the third page from the highest address (absolute address) <m) . next,
The relative address (n>) of the desired block is determined from the address table of the third page packet, and the absolute address of the desired block is calculated using j=m−n.

In addition, to delete each packet on the first and second pages, add the packet sizes stored in each table to find the total size to be deleted, and move blocks by this size. done (7th
(see figure).

Furthermore, the operation of the control device will be explained based on the flowchart of FIG. 8 showing its operation procedure.

The CPU 51 is connected to an external device 40 such as a host computer.
Temporarily stores the data (code) sent from the interface 41 in the reception buffer 52a, and retrieves the data from the reception buffer 52a (#1).
, check whether the printed ejection code exists (#2)
. If it is determined that the data does not exist, the data is divided into blocks as page data, the absolute address in the page memory area at the beginning of each block is stored in an address table, and a packet consisting of each block and table is divided into blocks for each page. form and store in page memory (#3, #4
). After that, return to #1 and repeat the same operation.

On the other hand, if it is determined in #2 that a print ejection code exists, the absolute address in the predecessor page memory area of each block stored in the address table is set as a relative address (n) based on the starting address of the packet. and store it in the table (#5). Furthermore, the memory size of the packet is also stored in the table, completing the registration of one packet in the page memory 52b (#6 and #7).

Next, check whether the number of currently registered packets is 2 or more, that is, whether the front page data flag and back page data flag are both set (#
8) If there are no more than 2 packets, return to #1 and repeat the same operation until the next packet is registered. If there are 2 or more, print one packet and check whether printing of the second packet has finished, that is, whether the back page data flag has been reset (#9, #10)
. If it has not been completed, return to #9 and wait for the printing of the second packet to be completed.

If it is determined that printing of 2 packets has been completed in #10,
The two printed packets 1 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 will be explained based on the flowchart of FIG. 9, especially the operation of deleting the packet from the page memory 52b (#1.1>).

If it is determined that both the front page data flag and the back page data flag have been reset at #10 in FIG.
Go delete from b.

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

Next, from the memory size of each packet stored in the table of each packet, the starting address of the packet of the next page is calculated, and the starting address for block movement is calculated (#22).

Furthermore, from the memory size of each packet recorded 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 amount of block movement is calculated. calculate(
#23>.

Then, from the block movement nine addresses calculated in #22, the memory size by the amount of block movement calculated in #23 is divided into blocks by the memory size to be deleted calculated in #21. The data is moved so that the top address of the next page becomes the highest address (#24>. As a result, both packets of both printed pages are deleted.

Further, if it is determined in #10 that both have not been reset, the deletion routine is not entered because there is page data that has not been printed yet.

In this way, even if a block of data is moved,
The absolute address of any 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 device that prints a page after storing print data to be printed and recorded on paper in a memory in block units, the position of the block in the memory is determined by a relative address. Therefore, by writing/hiding in the table, the absolute address of any block can be calculated by calculation even if the block position does not move, so each time the address stored in the table Table operations such as updating the table are omitted, making it possible to speed up the processing of printing operations.

[Brief explanation of the drawing]

FIG. 1 is an overall configuration diagram of a double-sided printing device according to an embodiment of the present invention, FIG. 2 is a block configuration diagram of a print control device of the same device, FIG. 3 is a schematic configuration diagram showing how blocks of paper are divided, and FIG.
The figure is a schematic configuration diagram showing one format of print data, Figure 5 is a memory map of page memory, Figure 6 is a schematic configuration diagram showing an address table of page memory, and Figure 7 is a schematic diagram showing packet deletion in page memory. A configuration diagram, FIG. 8 is a flowchart showing the operation procedure of the printing control device, and FIG.
The figure is a flowchart showing the packet deletion. 3... Image recording process device, 40... Host computer, 41... Interface, 51... C
PU, 52a...Reception buffer, 52b...Page memory, 53...Video RAM, 54...ROM,
56... Printing mechanism section.

Claims (1)

[Claims] (1) A printing device that prints on both sides of a sheet of paper, a page memory that divides the page-by-page print data output to this printing device and stores it for multiple pages, and stores the blocks formed by this division on a page-by-page basis. and control means for addressing the page memory to form packets and outputting the packets to the printing means, the control means, when forming the packets, A processing means for table-processing the relative address of the head of the block using the address and the head address of each block, and an arithmetic means for calculating the absolute address of the block using the table-processed relative address and a predetermined absolute address. What is claimed is: 1. A double-sided printing device characterized in that the double-sided printing device is characterized in that the double-sided printing device is configured to perform printing based on the calculated absolute address.