JPH07242030A - Perfecting press - Google Patents

Abstract

PURPOSE:To output data in page number order without applying alteration to a face-down output mechanism and mounting an excessive bit map memory by printing the surface data of a lower half and performing development on the upper half of a bit map memory of the next surface data in parallel to the printing of the surface data of the lower half. CONSTITUTION:After a bit map developing mechanism 6 performs the bit map development of first negative printing data, first bit map data is moved to the separate region of a bit map memory 1 by a bit map moving mechanism 9 and the bit map developing mechanism 6 performs the bit map development of second negative printing data. At the point of time when the bit map development of the first and second negative printing data is completed, the specific address of the bit map memory 1 is set to a transfer start position setting mechanism 2. Subsequently, the transfer of the second negative printing data is performed and the head position of the separate region of the bit map memory 1 is set to the setting mechanism 2 to transfer the bit map data of the first negative printing data.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a printer device for double-sided printing in a single bit map memory.

[0002]

2. Description of the Related Art FIG. 4 is a diagram for explaining a conventional printer device for performing double-sided printing in a single bit map memory.

Generally, in a printer device capable of printing only on one side of a sheet, in order to make the printed sheets overlap in the order of page numbers, it is sufficient to eject the sheets so that the printed surfaces face down. This is called face-down output.

In the case of expanding a printer device designed for face-down output when printing on one side and printing on both sides of the paper, first, printing on one side of the paper,
After that, it is general that the paper is returned to the inside of the printer, printed on the opposite surface of the paper, and then ejected.

At this time, if the processing is performed such that the front side is printed first and then the back side is printed, simply according to the order in which the print data is received, the back side is printed when the paper is ejected. Similar to the face-down output, the sheets are discharged with the back side down, and as a result, there is a problem that the pages are not arranged in the desired page number order such as (back side → front side → back side ...).

The above-mentioned conventional problems have the following three solutions. (a) Mount 2 planes of bitmap memory 1 first,
The print data on the front side is received by the code buffer 7, the bitmap is expanded on the plane 1 by the bitmap expansion mechanism 6, and then the print data on the back side is expanded by the code buffer 7.
Then, the bitmap is expanded by the bitmap expansion mechanism 6 to the plane 2. After that, when the bitmap data of the front and back sides are gathered, printing is performed on the paper in the order of back side to front side, and the face-down output is performed.

(B) The printer device is provided with a mechanism for turning over and ejecting the paper, so that the face-down output is performed during single-sided printing, and conversely, during double-sided printing, the paper is turned over and ejected. The face-up output is performed by ejecting the paper with the front side facing up.

(C) A higher-order mechanism (host computer or the like) for outputting print data to the printer device that performs the face-down output reverses the order of the front and back sides in advance, in the order of back side → front side → back side. The print data is sent to the printer device.

[0009]

In the conventional technique (a), it is necessary to mount the bit map memory 1 in two or more planes in the printer device, which causes a problem that the cost of the printer device is increased.

In the conventional technique (b), since it is necessary to provide a mechanism for turning over and ejecting the paper,
As in the case of the technique shown in (a), there is a problem in that the cost of the printer device is increased.

In the conventional technique (c), the upper mechanism
The (host) had to be aware of double-sided printing, and had to perform extra processing in advance to change the order of print data.

In view of the above-mentioned conventional drawbacks, the present invention eliminates the need to mount the above-mentioned extra hardware (two planes of the bit map memory), and does not need to change the face-down output mechanism. Furthermore, the host device
It is intended to provide a mechanism for outputting in order of page numbers in double-sided printing without performing extra processing on the (host).

[0013]

FIG. 1 is a diagram for explaining the principle of the present invention. The above-mentioned problems are solved by a printer device configured as follows.

(1) A printer device for performing double-sided printing of bitmap data of a bitmap memory 1 having a capacity at least twice the page print size, wherein the bitmap memory 1 and the bitmap memory 1 are A bitmap moving mechanism 9 for moving bitmap data, a bitmap protect mechanism 4 for suppressing writing to a specific range of the bitmap memory 1, and a write on the bitmap memory 1 for the bitmap protect mechanism 4. The bitmap protect position setting mechanism 3 that sets the range to be suppressed, the bitmap transfer mechanism 5 that reads the contents of the bitmap memory 1 and sends them to the printer engine 8, and the read range on the bitmap memory 1 The transfer start position setting mechanism 2 that instructs the bitmap transfer mechanism 5 And a bitmap expansion mechanism 6 for expanding the page print data received from the apparatus in the bitmap memory 1, and the bitmap expansion mechanism 6 sets the first page print data by the bitmap protect position setting mechanism 3. After the bitmap expansion is performed on the second area of the bitmap memory 1 excluding the first area, the bitmap moving mechanism 9 causes the bitmap memory 1 to move to the second area from the second area of the bitmap memory 1. The bitmap data of the first page print data is moved to the first area, and then the bitmap expansion mechanism 6 expands the bitmap of the second page print data to obtain the first and second areas.
When the bit map expansion of the page print data of is completed, the transfer start position setting mechanism 2 of the bit map memory 1
The start position of the bitmap expansion of the second area is set, the bitmap data of the second page print data is read from the bitmap memory 1, and the printer engine 8
To the transfer start position setting mechanism 2 and transfer the second page print data to the transfer start position setting mechanism 2.
The first position of the bitmap expansion of the first area 1 is set to transfer the first page print data, and in parallel with this, the bitmap expansion mechanism 6
Configures the following first page print data to be bit map expanded in the second area of the bit map memory 1.

(2) In the above item (1), the size of the paper designated in the print data and the bitmap memory
1 is provided with a paper size comparison mechanism 11 for comparing the size of 1 and a code buffer 7 for storing at least one page of print data received from a higher-level device, and the paper size is the size of the bitmap memory 1. If it is larger than half of the above, all of the first page print data is temporarily stored in the code buffer 7, and then the second page print data is expanded in the bitmap memory 1 and transferred. After that, the first page print data is developed in the bitmap memory 1 and transferred.

(3) In the above item (2), a buffer over detection mechanism 12 for detecting that the print data amount for one page exceeds the capacity of the code buffer 7 is provided, and the paper size comparison mechanism (11) ) Detects that the paper size is larger than half the size of the bitmap memory 1, and the buffer overflow detection mechanism 12 exceeds the capacity of the code buffer 7 while receiving print data of the front page. When it is detected that the print data is received, the bitmap development of the first page print data is performed, and after the transfer, the bitmap development of the second page print data is performed and the transfer is performed. Constitute.

[0017]

FIG. 1 is a diagram for explaining the principle of the present invention. 1 in the figure
Is a bitmap memory, which holds print data expanded into a bitmap. 2 is a transfer start position setting mechanism, and 5 is a bitmap transfer mechanism.
Reads the contents of 1 and holds the start position in bitmap memory 1 when sending to printer engine 8. 7
Is a code buffer, which holds print data received from the higher-level mechanism, for example, coordinate data, data length, and data including a code indicating the type of print data. Reference numeral 4 denotes a bitmap protection mechanism. The bitmap expansion mechanism 6 reads the print data from the code buffer 7 and removes the first area of the bitmap memory 1 protected by the bitmap protection mechanism 4. When the bitmap expansion is performed on the second area of the bitmap memory 1, the address output by the bitmap expansion mechanism 6 is compared with the value held by the bitmap protect position register 3 to specify the specified bitmap. It is configured to prevent writing to the bitmap memory in the first area below the protect position. Reference numeral 9 denotes a bitmap moving mechanism, which moves bitmap data from the second area (eg, upper half) of the bitmap memory 1 to the first area (eg, lower half).
10 is a sequence control mechanism, which is used for double-sided printing.
Appropriate values are set for each sequence in the bitmap protect position setting mechanism 3 and the transfer start position setting mechanism 2, and the bitmap movement mechanism 9 is instructed to move the bitmap.

In the printer device according to the present invention, the double-sided printing sequence is divided into five steps. In the first step, the sequence control unit 10 sets the bitmap protect position register 3 to the maximum position coordinate / 2 of the bitmap memory 1. Set to the position so that the writing to the first area (lower half) of the bitmap memory is protected, and the bitmap expansion mechanism 6 is set to the first page print data (for example, the print data of the front page). ) Indicate the bit map expansion. In the second step, Bitmap Protect Position Register 3
Is set at the lower end of the bitmap memory 1, and the bitmap moving mechanism 9 sets the second area (upper half) to the first area (lower half) of the bitmap memory 1.
Move the bitmap data to. In the third step, again set the bitmap protect position to bitmap memory 1
Of the first page print data (the print data of the front page) which has been subjected to the bitmap expansion by setting the maximum position coordinate / 2 position of the bitmap expansion mechanism 6 to the bitmap expansion mechanism 6. An instruction is given to develop a bitmap of the second page print data (print data of the back page). In the fourth step, the transfer start position setting mechanism 2 is set in the bitmap memory 1
Is set to the upper end (maximum position coordinate) of the second page print data (print data of the back page) to the bitmap memory.
Read from 1 and send to printer engine 8 to transfer to paper. In the fifth step, the transfer start position setting mechanism 2 is set to the maximum position coordinate / 2 of the bitmap memory 1/2.
The first page print data (the print data of the front page) which has been set to the position and has been bit map expanded is read from the bit map memory 1 and sent to the printer engine 8 so that the transfer to the paper is performed. In parallel with this, the bitmap expansion mechanism 6 transfers the next first page print data (print data of the front page) in the bitmap memory 1,
Control is performed so as to develop a bitmap in the second area (upper half). In the subsequent steps, by returning to the second step again and repeating the operation, printing on both sides is continuously repeated.

Therefore, according to the second aspect of the present invention, even in the printer apparatus in which the bit map memory 1 is mounted on only one plane, the conventional face-down output mechanism is not changed, and the extra bit is not used. Without mounting the map memory, up to half the size of the mounted bitmap memory 1 can be output in page order by double-sided printing. Further, by combining with the operation of claim 3 which will be described in detail in the next embodiment, the print data of the front page is stored in the code buffer 7 even in the case where the size of the installed bitmap memory 1 exceeds half the size of the paper. If it goes in and out, it is possible to output in page order by double-sided printing. Further, by the operation of claim 4 which will be described in detail in the next embodiment, it is possible to prevent a situation in which print data that does not meet the conditions of claims 2 and 3 cannot be printed in page order but cannot be printed on both sides. There is an effect that can be.

[0020]

Embodiments of the present invention will be described in detail below with reference to the drawings. The above-mentioned FIG. 1 is a diagram for explaining the principle of the present invention.
FIG. 3 is a diagram showing an embodiment of the present invention.
Shows an example of the overall configuration of the printer device according to the present invention,
FIG. 3 shows a configuration example of the bitmap protect of the present invention.

In the present invention, in the laser printer device shown in FIG. 2, a bitmap expansion mechanism (vector generator) 6 reads print data from the code buffer 7 and, for example, a two-dimensional address of X and Y is used. When performing bitmap expansion on the configured bitmap memory 1, the Y coordinate value of the address output by the bitmap expansion mechanism (vector generator) 6 is compared with the value held by the bitmap protect position register 3. Bitmap protect mechanism 4, which is configured to prevent writing to the bitmap memory below the specified bitmap protect position (value of the protect position register), and the upper half to the lower half of bitmap memory 1. Bitmap mover (bit mover) 9 to move the bitmap data to the print The size of the paper specified in the data and the size of the bitmap memory 1
(Actually half the size), and the paper size comparison program 11 that notifies the sequence control unit (MPU) 10 of the comparison result, and the print data amount for one page is the capacity of the code buffer 7. Sequence control unit (MPU)
The buffer overflow detection program 12 that notifies 10
It is a necessary means for carrying out the present invention. The same reference numerals indicate the same objects throughout the drawings.

The configuration and operation of the double-sided printing printer apparatus using the single bit map memory of the present invention will be described below with reference to FIGS. FIG. 2 is a diagram showing an embodiment of the present invention. FIG. 2 (a) shows an example of the overall configuration, which is configured as a control device of a laser beam printer, and FIG. The operation concept of the mover is shown, and FIG. 2 (c) shows the operation concept of the vector generator.

The operation of the printer device according to the first aspect will be described below. Reference numeral 1 is a bit map memory, which is composed of a normal DRAM and is connected to the image bus. The image bus has an address line separated into X and Y and a data line, and accesses the connected bitmap memory 1 with a two-dimensional address of X and Y. 10 is a microprocessor (hereinafter referred to as MPU)
That is, it controls the entire laser beam printer.

The program executed by the MPU 10 is stored in the main memory device (MM) 13, and the sequence control unit 10a in FIG. 1 is composed of software (sequence control program) as a part of this program. . or,
A portion of the main memory (MM) 13 in which a program is not stored is used as a code buffer 7, and drawing address data {for example, if the drawing data is a straight line, its drawing start coordinates (x, y), the line length (Δx, Δy), and the line type code data} are held. The MPU 10 and each peripheral circuit are connected via the illustrated system bus.

The system bus is a bus having one-dimensional address lines and data lines. The system bus includes a bit mover 9, a vector generator 6, a protect position register 3, a bitmap protect mechanism 4, and
Direct Memory Access Controller (DMAC) 5a,
The parallel / serial converter 5b is connected.

The bit mover 9 is connected to the system bus and has a control register which can be written from the MPU 10. By writing an instruction from the MPU 10 to the control register, the bit mover 9 is made to X, Y It is an LSI configured to output addresses in an appropriate order to move the bitmap memory, and is a so-called direct memory access controller (DMAC). The data written in the control register of the bit mover 9 is, for example, the start address (x1, y1) of the source data and the data area (Δx,
Δy), the start address (x2, y2) of the move destination data, and the code of the move instruction (transfer instruction).

Similar to the bit mover 9, the vector generator 6 is connected to the system bus to enable the MP generator.
It has a control register that can be written from U 10,
The LSI has a function of writing an instruction from the MPU to the control register to output X and Y addresses to the image bus in an appropriate order to draw a straight line on the bitmap memory. If the data written in the control register is the above-mentioned linear data, for example, as shown in the operation concept of FIG.
0, y0), data length (Δx, Δy), and line type code that indicates a straight line.

The bit map protect position register (hereinafter sometimes referred to as protect position register) 3 is
It is composed of a simple D latch, and the value of the protect position (that is, the Y coordinate on the bitmap memory) can be written from the MPU 10 via the system bus.
The written value is connected to the input of the protect position of the bitmap protect mechanism 4. The bit map protect mechanism 4 is connected between the vector generator 6 and the bit mover 9 and the image bus, and is configured as shown in FIG. That is, when the vector generator 6 writes the bit-mapped data into the bit map memory 1, the X address, the Y address, and the write signal are output, but the magnitude comparator in the bit map protect mechanism 4 is output. 40 compares the value from the protect position register 3 with the value of the Y address from the vector generator 6, and if Y address <protect position, outputs the write signal from the vector generator 6 to the image bus, When address ≧ protect position, the write signal is blocked so that writing to the bitmap memory is not performed. The DMAC 5a is a so-called direct memory access controller (DMAC), has a control register that can be written by the MPU 10 via the system bus, and according to the designation of the control register,
By sequentially outputting to the X and Y address lines on the image bus, the bitmap data in the bitmap memory 1 is read in parallel with the bitmap expansion operation in the vector generator 6, and the P / S conversion (parallel / parallel) is performed. Serial conversion) Send to 5b. DMA as well as general DMAC
C5a is a control register that also specifies the read start address
Since it has (RS), it can be used as a transfer start position. The P / S conversion 5b is the DMAC.
It converts the bitmap data received from 5a into a video signal and outputs it to the printer engine 8.

In the first step, the MPU 10 sets the protect position register 3 to the maximum Y of the bit map memory 1.
Half the value of the address is written, the drawing address data is read from the code buffer 7, and then written into the control register of the vector generator 6, and the bitmap expansion of the front page is performed. When the drawing address data for one page in the code buffer 7 has been read, the process moves to the second step.

In the second step, the MPU 10 writes the maximum Y address of the bit map memory to the protect position register 3, and the bit map data of the upper half of the bit map memory 1 is written to the control register of the bit mover 9. The front page is moved by writing control information that moves the page in half.

In the third step, the MPU 10 again writes a half value of the maximum Y address of the bitmap memory 1 to the protect position register 3 so that the already expanded table page of the bitmap is not destroyed. After that, the drawing address data is read from the code buffer 7 and written in the control register of the vector generator 6 to expand the back page bitmap. When the drawing address data for one page in the code buffer 7 has been read, the process moves to the fourth step.

In the fourth step, the MPU 10 writes the beginning Y address of the bitmap memory 1 as the transfer start position into the control register (RS) of the DMAC 5a, activates the DMAC 5a, and returns to the back page. To the printer engine 8 for transfer. After sending the back page to the printer engine and stopping the DMAC 5a, the process moves to the fifth step.

In the fifth step, the MPU 10 writes a half of the maximum Y address of the bit map memory 1 as the transfer start position to the control register (RS) of the DMAC 5a, activates the DMAC 5a, and displays it. Sends the page to Printer Engine 8 for transfer. In this step, in parallel with the transfer operation, the drawing address data is read from the code buffer 7 and written in the control register of the vector generator 6, and the bitmap expansion of the next table page is performed. If the DMAC 5a is stopped and the drawing address data for one page has been read,
Returning to the second step, the above steps are repeated until there is no more drawing address data.

Next, an embodiment of the printer device described in claim 3 will be described. The paper size comparison program 11 is realized as software in the main memory (MM) 13, and the MPU 10 executes the paper size comparison program 11 before starting the first step of claim 1. . The paper size comparison program 11 uses the paper size and bitmap memory of the print data in the code buffer 7.
When the paper size is larger than ½ of the size of the bitmap memory 1, the processing is switched and the following sequence of operations is performed. That is, MPU 10
Stores the print data of the front page in the first step. That is, when the drawing address data is read from the code buffer 7, the drawing address data is skipped while being stopped in the code buffer, and is stored in the code buffer 7, and bitmap expansion is not performed. When the drawing address data for one page in the code buffer 7 has been read, the process moves to the second step.

In the second step, the MPU 10 reads the drawing address data following the first step from the code buffer 7, writes it in the control register of the vector generator 6, and expands the back page bitmap. . When the drawing address data for one page in the code buffer 7 has been read, the process moves to the third step.

In the third step, the MPU 10 writes the beginning Y address of the bitmap memory 1 as the transfer start position into the control register (RS) of the DMAC 5a, and DMA
Start C 5a and send the back page to the printer engine 8 for transfer. After sending the back page to the printer engine 8 and stopping the DMAC 5a, the process proceeds to the fourth step.

In the fourth step, the MPU 10 reads the drawing address data of the table page stored in the code buffer 7, writes it in the control register of the vector generator 6, and develops the bitmap of the table page. I do. When the drawing address data of the front page in the code buffer 7 has been read, the process moves to the fifth step.

In the fifth step, the DMAC 5a is activated and the front page is sent to the printer engine 8 for transfer. When the DMAC 5a is stopped, the process returns to the first step again, and the above steps are repeated until the drawing address data is exhausted.

Finally, a method for realizing the printer device according to the fourth aspect will be described. When the MPU 10 executes the paper size comparison program 11 and detects that the paper size is larger than 1/2 of the size of the bitmap memory 1, the MPU 10 executes the first step of the above-mentioned claim 2, Starts the buffer overflow detection program 12, which is implemented as a program in the main memory (MM) 13. The buffer overflow detection program 12 detects that the code buffer 7 has no free area for storing drawing address data of the front page. The MPU 10 has finished reading the drawing address data up to the end of the code buffer 7, and the buffer overflow detection program 12 has no empty area in the code buffer 7 for the print data of the front page. When the drawing address data of the front page is not completed in the state of detecting the front page, for example, when the end mark is not detected, the front page printing is performed by referring to the information notified from the buffer overflow detection program 12. Detects that data cannot fit in code buffer 7. At this time, MPU 10
Switches the processing and operates in the following sequence.

In the first step, the print data of the front page that has been skipped halfway is read again and written in the control register of the vector generator 6, and the front page bitmap is expanded. When the drawing address data of the front page in the code buffer 7 has been read, the process moves to the second step.

In the second step, the MPU 10 writes the leading Y address of the bit map memory 1 as the transfer start position into the control register (RS) of the DMAC 5a, and DMA
The C 5a is activated and the front page is sent to the printer engine 8 to transfer it. If the DMAC 5a has stopped, move to the third step.

In the third step, the MPU 10 reads the drawing address data of the back page from the code buffer 7, writes it in the control register of the vector generator 6, and develops the bitmap of the back page. When the drawing address data for one page in the code buffer 7 has been read, the process moves to the fourth step.

In the fourth step, the DMAC 5a is activated and the back page is sent to the printer engine 8 for transfer. After sending the back page to Printer Engine 8,
When the DMAC 5a is stopped, the process returns to the first step of claim 3 again, and is repeated until there is no drawing address data.

In the above embodiment, on a single bit map memory, the front page is first expanded in the first half of the bit map memory, then moved to the lower half, and then the back page is expanded in the empty upper half. When doing so, so as not to destroy the expanded data of the lower half of the front page, with the bitmap protect mechanism 4,
The example of using the bitmap protect position setting mechanism 3 for setting the range in which the writing on the bitmap memory 1 should be suppressed in the bitmap protect mechanism 4 has been described, but in consideration of the gist of the present invention, the bitmap Even if the protect position setting mechanism 3 and the bitmap protect mechanism 4 are not provided, for example, an area for expanding the front page and the back page is defined, and the area is moved from the specified area to another area.
It goes without saying that the back page may be expanded in the moved empty area.

As described above, the double-sided printing printer device using the single bit map memory according to the present invention stores the front side data in the upper half of the single bit map memory capable of expanding the bit map data for two sides of the double side printing size. After developing and moving to the lower half, after developing the back surface data in the upper half, reading and printing the back surface data developed in the upper half, and printing the lower half surface data In parallel with the printing of the surface data, the double-sided printing by a single bitmap memory is performed by expanding the upper half of the bitmap memory of the surface data.

[0046]

As described above in detail, in the double-sided printing printer device using the single bit map memory of the present invention, according to the inventions of claims 1 and 2, the bit map memory has only one plane. Even in the installed printer device, up to half the size of the installed bitmap memory paper can be output in page order by double-sided printing. Further, by combining with the operation of the invention described in claim 3, double-sided printing can be performed if the print data of the front page can be completely stored in the code buffer even on the paper that exceeds half the size of the mounted bitmap memory. It is possible to output in page order. Further, according to the invention described in claim 4, in the print data that does not meet the conditions of claims 1, 2 and 3, although it is not possible to output in page order, it is possible to prevent a situation in which double-sided printing cannot be performed. is there.

[Brief description of drawings]

FIG. 1 is an explanatory view of the principle of the present invention.

FIG. 2 is a diagram showing an embodiment of the present invention (No. 1).

FIG. 3 is a diagram showing an embodiment of the present invention (part 2).

FIG. 4 is a diagram illustrating a conventional printer device that performs double-sided printing in a single bitmap memory.

[Explanation of symbols]

1 Bitmap memory 2 Transfer start position setting mechanism 3 Bitmap protect position setting mechanism, Bitmap protect position register 4 Bitmap protect mechanism 5 Bitmap transfer mechanism 5a Direct memory access controller (DMAC) 5b Parallel / serial converter (P / S conversion) 6 Bitmap expansion mechanism (vector generator) 7 Code buffer 8 Printer engine 9 Bitmap movement mechanism (bit mover) 10 Sequence control unit (MPU) 11 Paper size comparison mechanism (paper size comparison program) 12 Buffer over detection mechanism (Buffer over detection program) Paper size Position information set in transfer start position setting mechanism (transfer start position)

Claims (4)

[Claims] 1. A printer device for double-sided printing of bitmap data of a bitmap memory (1) having a capacity twice as large as a page print size, the bitmap memory (1) and the bitmap. A bitmap moving mechanism (9) that moves the bitmap data to another position in the memory (1), and a bitmap that reads the bitmap data from the bitmap memory (1) and sends it to the printer engine (8). The transfer mechanism (5), the transfer start position setting mechanism (2) for instructing the bitmap transfer mechanism (5) to read the range on the bitmap memory (1), and the page print data received from the host device. A bitmap expansion mechanism (6) for expanding from a specific address of the bitmap memory (1), wherein the bitmap expansion mechanism (6) expands the bitmap of the first page print data. After that, the bitmap moving mechanism (9) moves the bitmap data of the first page print data to another area of the bitmap memory (1), and then the bitmap expanding mechanism (9). 6) performs bitmap expansion of the second page print data,
When the bit map expansion of the second page print data is completed, the specific address of the bit map memory (1) is set in the transfer start position setting mechanism (2), and the second page print data of the second page print data is set. Transfer, then transfer start position setting mechanism
In (2), the head position of the other area of the bitmap memory (1) is set, and the bitmap data of the first page print data is transferred. 2. A printer device for performing double-sided printing of bitmap data of a bitmap memory (1) having a capacity at least twice the page print size, the bitmap memory (1) and the bitmap. A bitmap moving mechanism (9) for moving the bitmap data of the memory (1), a bitmap protect mechanism (4) for suppressing writing to a specific range of the bitmap memory (1), and the bitmap protect mechanism. (4) A bitmap protect position setting mechanism (3) that sets the range where writing on the bitmap memory (1) should be suppressed, and the printer engine (3) by reading the bitmap data of the bitmap memory (1). Bitmap transfer mechanism to send to (8) (5)
A transfer start position setting mechanism (2) for instructing the bitmap transfer mechanism (5) to read a range on the bitmap memory (1), and the page print data received from the host device to the bitmap memory (1). Bitmap expansion mechanism
(6), wherein the bitmap expansion mechanism (6) excludes the first page print data from the first area set by the bitmap protect position setting mechanism (3). After performing the bit map expansion to the second area of the memory (1), the bit map moving mechanism (9) moves the first area from the second area of the bit map memory (1) to the first area.
The bitmap data of the first page print data is moved to the area of, and then the bitmap expansion mechanism (6) expands the bitmap of the second page print data. When the bit map expansion of the page print data is completed, the start position of the bit map expansion of the second area of the bit map memory (1) is set in the transfer start position setting mechanism (2), The bitmap data of the second page print data is read from the bitmap memory (1) and sent to the printer engine (8) to transfer the second page print data, and then the transfer start position setting mechanism. (2)
Is set to the start position of the bitmap expansion of the first area of the bitmap memory (1) to transfer the first page print data, and in parallel with this, the bitmap expansion is performed. A double-sided printing printer device characterized in that the mechanism (6) is configured to perform bitmap expansion of the following first page print data into the second area of the bitmap memory (1). 3. The size of paper specified in the print data and
(), A paper size comparison mechanism (11) for comparing the size of the bitmap memory (1) and a code buffer (7) for storing at least one page of print data received from a host device. If the paper size () is larger than half the size of the bitmap memory (1), the entire first page print data is temporarily stored in the code buffer (7), and then the first page print data is stored. The page print data of No. 2 is expanded in the bitmap memory (1) and transferred, and then the first page print data is transferred from the code buffer (7) to the bitmap memory (1).
The double-sided printing printer device according to claim 1 or 2, wherein the double-sided printing printer device is configured to be developed in (1) and transfer is performed. 4. A buffer over detection mechanism (12) for detecting that the amount of print data for one page exceeds the capacity of the code buffer (7), and the paper size comparison mechanism (11) size of paper()
Is larger than half the size of the bitmap memory (1), and the buffer overflow detection mechanism
When (12) detects that the print data exceeding the capacity of the code buffer (7) is received while receiving the print data of the front page, the bit map expansion of the first page print data is performed, 4. The double-sided printing printer device according to claim 3, wherein after the transfer, the second page print data is subjected to bit map development and transferred.