JPH0768863A - Printer - Google Patents

Abstract

PURPOSE:To perform quick processing, even when the jamming and the like of a sheet particularly occur, and efficiently perform a printing processing. CONSTITUTION:A printer measures the time when an intermediate code stored in a page buffer 8 is expanded into a frame memory 10 and compares the measured time with a preset reference time, whereby page data whose expanding time into the frame memory 10 requires more than a predetermined time are held without being erased for a fixed period of time after pattern data are transferred from the frame memory 10 and, when the jamming of a sheet does not occur, the data are erased after, for example, the delivery of the sheet.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a printing apparatus which performs printing processing based on information output from a host device, and particularly to reduce the printing processing speed even when a paper conveyance failure such as a paper jam occurs. Related printing device.

[0002]

2. Description of the Related Art Conventionally, various printer devices such as an LED printer, a laser printer, and an LCS printer have been known as a printing device for performing a printing process in accordance with information output from a host computer or other host device. Such a printing device analyzes character codes and print control information output from a host computer, converts them into intermediate codes, and executes command execution processing to create pattern data in bitmap format. Store in frame memory. This frame memory has a memory area corresponding to print dots on the paper in a one-to-one correspondence. When the pattern data described above is expanded in the frame memory and the expansion processing of the pattern data for one page of paper is completed, Pattern data for one page (second page) is developed.

Conventionally, the so-called dynamic memory allocation method has been used in the pattern data expansion processing to the frame memory as described above in order to improve the processing speed. That is, the frame memory is managed in block units, and when the pattern data of the first page is transferred to the print head by a predetermined block, the pattern data of the second page is expanded in the area after the transfer, and the pattern data for the frame memory is stored. The data expansion and transfer processing are continuously and efficiently performed.

However, in the printing apparatus having the above structure,
When the pattern data of the previous page expanded in the frame memory is transferred and then the pattern data of the next page is expanded, the pattern data is sequentially transferred in block units even before all the pattern data of the previous page is transferred from the frame memory. Will be erased. Therefore, for example, when a paper conveyance failure such as a paper jam occurs, it becomes a problem. Therefore, in the conventional printing apparatus, a jam recovery function is added in consideration of this. That is, the pattern data stored in the frame memory is transferred to the print head, and the corresponding intermediate code is held in the buffer until it is confirmed that the paper printed by the print head has been discharged out of the machine, When a paper jam occurs, the intermediate code is expanded in the frame memory again.

[0005]

However, in the conventional printing apparatus as described above, the data corresponding to the paper conveyance failure such as the paper jam is only stored in the buffer in the form of the intermediate code, and the frame memory is used. Is not stored in the form of pattern data. Therefore,
For example, in the case of print data, such as outline font data, ruled line data, and graphic data, which requires time to expand into the frame memory, it takes a long time for the pattern data to be expanded again into the frame memory. That is, when a trouble such as a paper jam occurs in the conventional printing apparatus, it takes a long time to expand the data in the frame memory again, and the efficient printing process cannot be performed.

The present invention solves the above problems, and provides a printing apparatus which can perform efficient printing processing quickly even when a paper conveyance failure such as a paper jam occurs. To aim.

[0007]

The present invention is applied to a printing apparatus for generating pattern data to be printed on an image memory based on print information input from a higher-level device and performing printing processing according to the pattern data. Image data generating means for generating pattern data from the print information and developing the pattern data in the image memory; time measuring means for measuring the time required from the start to the end of the development of the pattern data for one page of paper in the image memory; Data transfer means for transferring the data in the image memory to the printing section, and the data transfer means, in the transfer processing, an erase mode for erasing an area in which the data of the image memory is read, and a data as it is. A holding mode for holding the page data that has been held by the timekeeping means for a predetermined time or longer is transferred in the holding mode. It is a configuration.

[0008]

In the printer of the present invention, the time for developing the pattern data from the intermediate code to the frame memory is measured by the time measuring means, and the measured time is compared with the preset reference time, so that the frame memory For page data that requires a development time longer than the reference time, the pattern data is transferred from the frame memory, and after confirming that there is no paper conveyance failure such as a paper jam, the corresponding pattern data is deleted. Is. With this configuration, if a paper conveyance error such as a paper jam occurs for page data that requires time to develop the pattern data in the frame memory, the pattern data held in the frame memory is immediately transferred to the print head. It is possible to output and perform efficient print processing.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described in detail below with reference to the drawings. FIG. 1 is a diagram showing the system configuration of the printing apparatus of this embodiment. As shown in FIG.
2 and an engine controller 3). The I / F controller 2 includes a CPU (central processing unit) 4, a ROM 5, a RAM 6, a reception buffer 7,
Page buffer 8, character generator (hereinafter C
9) and a frame memory 10.
The I / F controller 2 is also connected to a host computer 12, which is a higher-level device, via a host I / F 11.

The print information output from the host computer 12, that is, the character code and the control information for the print processing is output to the reception buffer 7 via the host I / F 11 of the Centronics specification. Further, the CPU 4 as image data generating means performs system control in accordance with a program stored in the ROM 5, for example, command analysis of the print information input to the above-mentioned reception buffer 7, conversion into an intermediate code, and writing in the page buffer 8. Alternatively, command execution processing is performed on the intermediate code written in the page buffer 8 to control the creation of pattern data.
The RAM 6 stores various data generated during the print control process. Further, the page buffer 8 is, as shown in FIG.
It has the capacity to store intermediate codes for multiple pages.

Further, the CG 9 stores the pattern data corresponding to the character code, and converts the data identified as the character code in the print information into the corresponding pattern data during the command execution processing of the CPU 4 described above.

The frame memory 10 has a storage capacity for one page of paper and stores the pattern data output from the CG 9 based on the control information. Also, the frame memory 1
The pattern data stored in 0 is output to the engine controller 3 via the video I / F 13 under the control of the CPU 4.

On the other hand, FIG. 2 is a diagram for explaining the memory configuration of the page management memory provided in the RAM 6 described above. The page management memory 6'shown in the figure includes a page buffer 6a ', a copy number storage area 6b', and a confirmation area (hereinafter referred to as an FRAM data area) 6 for confirming completion of data expansion to the frame memory.
c ', a read mode flag storage area 6d'. The page number to be printed (hereinafter referred to as No) is registered in the page buffer 6a ', the copy number of each page is registered in the copy number storage area 6b', and the frame memory is stored in the FRAM data area 6c '. 1
In 0, another complete / incomplete data indicating whether or not the pattern data of each page has already been developed is registered. Further, the frame memory 1 is stored in the read mode flag storage area 6d '.
After transferring the pattern data from 0, the frame memory 1
Information on whether to erase the data remaining in 0 is registered.
This registration is performed by setting either a clear mode flag or a not clear mode flag described later.

On the other hand, as shown in FIG. 1 described above, the engine controller 3 outputs image data to the print head 14 in the printer and controls the paper discharge sensor 15 to read a paper detection signal. Further, the engine controller 3 is an image forming unit of the printing apparatus, for example, each unit such as the photoconductor drum 16, the transfer unit 17, a charger (not shown), a developing unit, and the like, and a sheet feeding unit that feeds a sheet from a sheet feeding cassette 18. Drive control of the rollers 18 ', rotation control of the standby roll 19, heating control of the fixing roll 20, and the like are performed.

The operation of the above-mentioned image forming unit will be briefly described. The paper stored in the paper feed cassette 18 is carried out on the conveyance path according to the rotation of the paper feed roller 18 ', and the paper is advanced by the standby roll 19. Is temporarily stopped, the transport posture is adjusted, and then the image is fed to the image transfer unit on the downstream side at a predetermined timing described later. The photoconductor drum 16 and the transfer device 17 are arranged to face each other in the image transfer section, and the toner image formed on the peripheral surface of the photoconductor drum 16 is transferred onto a sheet. The sheet on which the toner image has been transferred is thermally fixed by the fixing device roll 20 and then discharged to the outside of the machine. The paper discharge sensor 15 detects the paper discharged to the outside of the machine and outputs the detection signal to the engine controller 3.

FIG. 3 shows a data flow of the entire printing process in the printing apparatus 1 having the above structure. Hereinafter, each operation will be described with a flowchart based on the processing shown in FIG. First, as described above, the print data output from the host computer 12 is stored in the host I / F 11
Is written in the reception buffer 7 via. FIG. 4 is a flowchart specifically explaining this reception process. That is, the CPU 4 determines whether or not there is a free area in which print data can be written in the reception buffer 7 (step (hereinafter referred to as S) 1), and if there is no free area in the reception buffer 7, outputs a busy signal to the host computer 12. The supply of print information from the host computer 12 is stopped (S1
Is N (no), S2). On the other hand, if there is a free area in the reception buffer 7 (S1 is Y (yes)), the input of print data is judged and data reception processing is performed (S3, S4).
The print information is stored in the reception buffer 7 (S5).

When the print data is stored in the receiving buffer 7 as described above, as shown in FIG.
4 analyzes the print data. FIG. 5 is a flowchart specifically explaining the print data analysis process (page data creation process). The CPU 4 first determines whether or not print data is stored in the above-mentioned reception buffer 7 (step (hereinafter referred to as U) 1), and if the reception buffer 7 is present.
If the print data is not stored in, the process is not performed, but if the print data is stored in the reception buffer 7, it is determined whether or not there is an empty area in the page buffer 8 (U2).
Here, if the page buffer 8 also has a free area (U2
Y), the print data is read from the reception buffer 7, data analysis is performed, the data is converted into an internal code of the printer 1 and stored in the page buffer 8 (U3). Then, it is judged whether the print data for one page has been converted into the corresponding internal code (U4). This determination is made by, for example, checking whether or not there is a page break command included in the print information, and if the page break command is not included yet, the above processing is repeated (U4 is N,
U1, ...) On the other hand, if you confirm the page break command, 1
The completed page number is registered in the page buffer 6a 'of the page management memory 6'to indicate that the print data for the page has been converted into the internal code (U5). By the above processing, the intermediate code converted into the internal code is written in the page buffer 8. By repeating this process, the intermediate code for several pages is stored in the hage buffer 8. Further, the Nos of all pages converted into the intermediate code are also registered in the page management memory 6 '. Further, during the above-described analysis processing, if the print data includes a command for specifying the copy mode, the data of the number of copies is registered in the copy number storage area 6b 'in the page management memory 6'.

When several pages of intermediate codes are stored in the page buffer 8 as described above, pattern data generation processing (intermediate code execution processing) is then performed, as shown in FIG. FIG. 6 is a flowchart illustrating this pattern data generation processing. First, the CPU 4 determines whether or not the intermediate code is stored in the page buffer 8 (step (hereinafter referred to as V) 1). If the intermediate code is not stored in the page buffer 8, the driving of the timer described later is stopped. (V1 is N, V2). Even if the intermediate code is stored in the page buffer 8, the frame memory 1
If there is no free area in 0, the timer drive is stopped (V3 is N, V2). The timer as a time measuring means, from the time when the intermediate code stored in the page buffer 8 is read,
The time until the pattern data is expanded in the frame memory 10 after the command is executed is measured, and by measuring the above-mentioned time by this timer, the type of the intermediate code stored in the page buffer 8 can be dealt with. hand,
The length of time until the expansion of the pattern data is completed in the frame memory 10 is measured and used for later comparison with the reference time.

That is, in the above determination (V1, V3), if the page buffer 8 has an intermediate code and the frame memory 10 also has a free area (V1 and V3 are both Y), the page buffer 8 outputs the intermediate code. Read the code,
The frame memory 10 is executed by executing the command designated by the command.
The process of expanding the pattern data into the pattern is started (V4). Next, it is judged whether the timer is in the time counting process (during driving) (V5),
If the timer is driving, it is judged that the pattern data of one page is completed (V5 is Y, V7), but the timer is not driven in the first process (flow) (V5 is N), so the timer is driven immediately. Yes (V6).

Thereafter, it is judged whether the pattern data for one page has been expanded in the frame memory 10 (V7), and the above-described processing is repeated until the expansion of the pattern data for one page in the frame memory 10 is completed (V7 is N. , V1-V7).
After that, when the pattern data for one page is expanded in the frame memory 10 (V7 is Y), the timer is stopped (V
8), the No. of the page for which the pattern data expansion processing to the frame memory 10 is completed is indicated by the FRA of the page management memory 6 '.
It is registered in the M data 6c '(V9). This registration process is
F corresponding to the page number registered in the page buffer 6a '
This is done by setting a flag in the RAM data area 6c '.

Next, the CPU 4 compares the preset reference time with the time measured by the above timer (V10), and sets the clear mode flag when the time measured is shorter than the reference time (time measured <reference time). (V10 is N, V11), when the clock time is longer than the reference time (clock time> reference time), the knot clear mode flag is set (V10 is Y, V
12). This setting is performed by setting the corresponding flag in the read mode flag 6d 'in the page management memory 6'described above. Here, the clear mode flag is
The knot clear mode flag is a flag for instructing the clearing of the pattern data stored in the frame memory 10 and the knot clear mode flag is a flag for instructing the holding of the pattern data stored in the frame memory 10, and the determination (V10) is performed.
Select one of the modes based on. That is, by comparing the reference time with the time measured by the timer as described above, when the time measured by the timer exceeds the reference time, the pattern data developed in the frame memory 10 is handled as described later. It is assumed that the sheet is not erased until it is ejected out of the machine. Conversely, when the time measured by the timer is shorter than the reference time, the pattern data developed in the frame memory 10 is transferred to the print head and then is transferred in block units as before. To erase with.

When the expansion process of the pattern data for one page in the frame memory 10 is completed as described above, the CPU 4
Outputs a transfer permission (V13) and resets the above-mentioned timer (V14). The above-mentioned transfer permission output is, specifically, as shown in FIG. 3 described above, a DMAC (Direct Memory Access) as a data transfer means from the CPU 4.
The start signal is output to 4 ', and at this time, only the initial address and the final address of the pattern data read from the frame memory 10 are designated. Based on the above output, the DMAC 4 ′ sequentially reads the pattern data stored in the frame memory 10 from a specified initial address and transfers it to the engine controller 3 via the video I / F 13.

On the other hand, the engine controller 3 receives the above-mentioned pattern data and starts carrying out the paper by a start command output from the CPU 4 prior to the input of this data. That is, as shown in the flow chart of FIG. 7, the engine controller 3 judges whether the print start is possible (step (hereinafter referred to as E) 1). If the print start is not possible (E1 is N), the current print is performed. If it is in the print startable state (E1 is Y), it is determined whether the instruction of the start command is output from the I / F controller 2 (CPU 4) (E3). And the I / F controller 2
If there is no print start instruction from (E3 is N), the instruction is waited, and if there is a print start instruction (E3 is Y), a flag indicating that the printing process for the first page is in progress is set (E4 ), Output a drive signal to the paper feed roller 18 ',
Paper is fed from the paper feed cassette 18 (E5), and the paper carried out from the paper feed cassette 18 is conveyed to the standby roll 19. At this point, the engine controller 3 detects this and notifies the I / F controller 2 that the paper has reached the standby roll 19 (E6, E7).

In this way, when the restart signal is sent from the I / F controller 2 to the engine controller 3 while the paper reaches the standby roll 19 and waits for re-feeding, the engine controller 3 will wait. A re-feeding signal is output to 19 (E8), and exposure based on the pattern data transferred from the print head 14 to the photosensitive drum 16 via the video I / F 13 is started. Further, the engine controller 3 outputs a drive signal to an image forming process such as a developing device and a transfer device to execute an image forming process on a sheet (E9). Finally, it is confirmed that the paper ejection sensor 15 detects the ejection of the paper (E1
0) When it is confirmed that the paper has been ejected, the in-process flag is reset (E11), and the I / F controller 2 is notified that the paper has been ejected (E12). Since the printing apparatus 1 of the present embodiment can carry a maximum of three sheets of paper in the apparatus, the flags set in the above process (E4) can be sequentially set to the flags 1 to 3. Similarly, the flag reset process (E11) is also sequentially reset from the flag 1 to the flag 3 described above.

During the above printing process, the pattern data of the next page is written in the memory area where the pattern data is transferred from the frame memory 10, and the original data is erased. There is a transfer mode in which the original data is retained without writing the pattern data of the page.

The case of the above-mentioned data erasing mode and data holding mode will be described below. However, the processing in the printing apparatus 1 may be an instruction to copy a plurality of pieces of print information, and the transfer processing described above including the case of this copy mode will be described in detail with reference to the flowchart of FIG.

As described above, when the expansion processing of the pattern data for one page is completed and the transfer permission is output from the CPU 4 (step (hereinafter ST) 1 is Y), the copy mode (hereinafter copy mode) is set. It is judged whether or not the designation is given (S)
T2). The designation of the copy mode is determined by a command included in the print information output from the host computer 12, and if the number of copies registered in the page management memory 6'is designated, the copy mode is designated.

Here, when the printer 1 of this embodiment is in the copy mode (ST2 is Y), the CPU 4 judges whether the copy process is currently being executed (ST3), and the copy process is still started by the first judgment. (ST3 is N), the number of copies is set in a copy counter (not shown) (ST
4). This copy number information is obtained from the copy number data registered in the copy number storage area 6b 'of the page management memory 6'. Next, the copy counter data is "1"
It is determined whether or not (ST5). Here, if the data of the copy counter is "1" (ST5 is Y), the process proceeds to ST11 to judge whether the time measured by the timer exceeds the reference time. Judgment is made (ST5)
Becomes N. Therefore, the process proceeds to the process (ST6), and the transfer in the not clear mode (NC mode) is set so as to hold the pattern data stored in the frame memory 10 during the copy process. Then, the aforementioned start command is output to the engine controller 3 and the input of the ready signal output from the engine controller 3 is waited (ST
7).

Thereafter, when the ready signal is output from the engine controller 3 (Y in ST7), the DMAC 4 '
Thus, the transfer of the pattern data stored in the frame memory 10 is started (ST8). This transfer processing is performed in the not-clear mode set as described above, and the data in the frame memory 10 after transfer is retained without being erased. After that, it is judged whether the transfer process is completed (ST9),
When the transfer process is completed (ST9 is Y), the data of the number of copies of the copy counter is decremented (ST10), and then the process returns to the determination (ST2).

After that, the above processing (ST2 to ST10) is repeated until the data of the copy counter becomes "1",
When the remaining number of designated copies is 1 (ST5
Is Y), the process proceeds to the determination (ST11). This judgment (ST
11), even when the copy mode is not set (ST2 is N)
This is a determination that is made, and when one sheet is printed (the remaining one sheet is printed in the copy mode), the read mode flag storage area 6d 'of the page management memory 6'is confirmed and the read mode flag of the corresponding page No. It is determined whether the flag of the clear mode or the not clear mode is set in the storage area 6d '. That is, if the print data of the corresponding page is data such as outline font data or graphic data that requires time to expand in the frame memory 10, the data is transferred in the not clear mode (ST11 is Y). That is, in this case, the print data is time-consuming to develop in the frame memory 10, and when the pattern data is transferred from the frame memory 10 to the engine controller 3 (print head 14), the data developed in the frame memory 10 is transferred. The knot clear mode is set to hold (ST12).

Thereafter, the start command described above is output to the engine controller 3, the input of the ready signal output from the engine controller 3 is waited for (ST13), and when the ready signal is output (Y in ST13), the frame memory 10 is output. To transfer the pattern data to (ST1
4). This transfer processing is performed in the not-clear mode set as described above, and the data in the frame memory 10 after transfer is retained without being erased. After that, the transfer processing is completed, and it is determined whether or not the sheet on which the corresponding print data is recorded is detected by the sheet discharge sensor 15 (ST15).
Then, when it is confirmed that the corresponding paper has been ejected (Y in ST15), it is unlikely that the corresponding paper is jammed in the printer 1, so the frame memory 1
The pattern data expanded to 0 is cleared (erased) (ST16).

On the other hand, in the judgment (ST11), the page N registered in the read mode flag storage area 6d 'is displayed.
If the clear mode is set to o (ST11 is N), the print data of the page is not the data such as outline font data that requires time to expand into the frame memory 10, so clear mode transfer is set ( ST17). Then, similarly to the above, when the start command is output to the engine controller 3 and the ready signal is output (ST18 is Y), the frame memory 10
The transfer of the pattern data is started (ST19). This transfer processing is performed in the clear mode set as described above, and the data in the frame memory 10 after transfer is erased.
After that, when the transfer process is completed (ST20), a determination (S
Return to T1). That is, in this case, the next page data is expanded in the area of the frame memory 10 where the transfer is completed for each predetermined block. Even with such processing, if a paper jam or the like occurs, the data can be immediately expanded from the page buffer 8 to the frame memory 10, and there is no problem.

Next, the processing operation when a paper jam occurs during the printing process will be described with reference to FIGS. 9 and 10. FIG. 9 shows the engine controller 3 when a paper jam occurs.
11 is a flowchart illustrating a processing operation on the side of FIG.
3 is a flowchart illustrating a processing operation on the I / F controller 2 side. The detection of the paper jam uses a known detection technique such as a method using a general jam timer.

First, when a paper jam is detected, an interrupt detection routine is executed. As shown in FIG. 9, the engine controller 3 issues a jam alarm (step (hereinafter W) 1) and the I / F controller 2 (CPU
The jam occurrence state is notified to (4) (W2), and the completion of jam processing is waited (W3).

On the other hand, on the I / F controller 2 side, the paper jam is known by the above-mentioned notification of the jam occurrence, and the printing process is interrupted as shown in FIG. 10 (step (hereinafter referred to as J)).
1) Judge the transfer mode (J2). Here, if the transfer of the pattern data from the frame memory 10 is in the not clear mode (clear after completion of paper discharge), DMA
The start point of the page is returned to the transfer start address of the transfer processing by C4 '(J3). That is, in the not-clear mode, when the pattern data is output from the frame memory 10, the data in the frame memory 10 is held immediately without being erased.
The pattern data held at 0 should be read again from the transfer start address. Therefore, in this case, thereafter, the transfer condition such as the reset of the transfer start address is reset in the judgment (J7), the transfer permission is waited, and if the transfer permission is given, the pattern data is read from the transfer start address. , To the engine controller 3 (print head).

On the other hand, in the above judgment (J2), when it is judged to be the clear mode (normal) (J2 is normal),
Jam recovery control described below is performed (J4 to J
7). The jam recovery control will be described below. That is, in the judgment (J4), Np (the number of pages for which a print start command has been issued) -EM (the number of sheets of paper remaining in the printer 1 when a jam occurs) is calculated. In this calculation, Np-EM
Is not more than "0" (J4 is N), the process proceeds to (J5), EM-Np = EM is calculated, and P (page number indicating the page registered in the page management memory 6 ') is set. -1
Subtract.

On the other hand, if Np-EM is "0" or more in the above calculation (J4 is Y), P = P, CC (copy counter for instructing the number of copies) = as the correction transfer condition in the process (J6) = EM. Finally, the transfer condition is set again by the judgment (J7), and the transfer is permitted.

The above jam recovery control will be described below using specific numerical values. First, as a specific example, a case where a paper jam occurs at the time when two sheets of paper are ejected from the printer 1 during the printing process of all the data of three pages in the copy mode of two sheets will be considered. In this case, EM
(Number of sheets remaining in the printer 1 when a jam occurs)
Is the maximum number of sheets that can be conveyed in the printer 1, and Np (the number of pages for which a print start command has been issued) is 1
The page. Therefore, in this case, judge (J4)
, EM is “3” and Np is “1”, so N
p-EM becomes "-2", and Np-EM <0. Therefore, the judgment (J4) at this time is N, and the processing (J4)
In 5), EM-Np is 3-1 = 2, and EM = 2 is calculated. Further, since P (page number indicating the page registered in the page management memory) is "3", processing (J5)
Then, P = 3-1 (P-1) = 2. Then, in the judgment (J4) again, Np is "2", and this time Np-
Since EM is “0”, the judgment (J4) is Y. Finally, in the process (J6), P =
2, CC = EM = 2. Therefore, in the case of this example, the data transfer of 2 pages (P pages) is set again, and the number of copies of 2 sheets (CC) is set in the copy counter.

Therefore, in the case of this example, after the above-mentioned transfer conditions are set, the transfer permission is waited, and thereafter the processing is performed in accordance with the above-mentioned set conditions (J4). Next, as a specific example, a case where a paper jam occurs at the time when two sheets of paper are ejected from the printing apparatus during the printing process of all the data of five pages in the one-sheet printing mode will be considered. In this case, Np (the number of pages for which the print start command has been issued) is 1 in the determination (J4), and EM (the number of sheets of paper remaining in the printer 1 when a jam occurs) is the maximum of 3, Np-EM becomes "-2" as described above, and is judged (J
4) is N. Therefore, in the process (J5), 3-1 =
2 (EM-Np = EM), and EM = 2. Also,
Since P (page number indicating the page registered in the page management memory) is 5, P = 5-1 (P
−1) = 4, and in the judgment (J4) again, Np −
Judge EM> 0. At this time, Np is "1" and EM is "2", so Np-EM is "-1", and the judgment (J4) is N at this time as well. Therefore, process again (J
5) is executed to obtain 2-1 = 1 (EM-Np = EM) and P = 4-1 (P-1) = 3. Then, if the judgment (J4) is executed again, Np-EM is 1-1 =
It becomes 0, and the judgment (J4) becomes Y.

Therefore, in the subsequent processing (J6), P = 3 and CC = EM = 1 are set as the correction transfer conditions from the above result, and the transfer conditions are reset and the transfer is permitted at the judgment (J7). That is, in the case of this example, the data transfer of three pages is set again and one copy number is set in the copy counter.

Finally, as a specific example, let us consider a case where a paper jam occurs at the time when one sheet of paper is not discharged from the printer during the printing process of the data of one page in the copy mode of two sheets. In this case, in the determination (J4), Np (the number of pages for which the print start command has been issued) is 2 pages, and EM (the number of sheets remaining in the printer 1 when a jam occurs) is 2 sheets at the maximum, and Np -EM becomes "0". Therefore, in this example, the judgment (J4) is Y immediately.
Therefore, the correction transfer condition P = 1 and CC = E in the process (J6).
When M = 2, the transfer condition is set again by the judgment (J7), and the transfer is permitted. That is, in the case of this example, the data transfer for one page is set again, and the copy counter is set to the number of copies of two sheets.

As described above, when the data transfer condition and the data of the number of copies are set again and the mechanical jam processing by the operator is completed, the above judgment (W3) becomes Y and the data of the number of recovery sheets is I. It is output to the / F controller 2 (W4), and the engine controller 3 returns to the ready state (W5).

As described above, according to the printing apparatus 1 of the present embodiment, when an abnormality occurs in the sheet conveyance such as a sheet jam, the pattern data development time in the frame memory 10 is measured by the timer and the reference time is set. In the above case, by holding the data in the frame memory 10 when the pattern data is transferred from the frame memory 10, it is possible to immediately output the pattern data again.

[0044]

As described above in detail, according to the present invention, when the intermediate code previously stored in the page buffer is expanded in the frame memory, the time required for the expansion is measured, and the measured time is the reference time. If the above is satisfied, the pattern data expanded in the frame memory is controlled so as not to be erased when it is printed out on the paper, and the paper such as outline font data or graphic data that requires time for expansion processing is printed. Even if the paper jams, the data can be easily output again.

Therefore, even when an abnormality occurs in the sheet conveying system such as a sheet jam, the printing process can be performed efficiently and promptly.

[Brief description of drawings]

FIG. 1 is a system configuration diagram of a printing apparatus according to an embodiment.

FIG. 2 is a configuration diagram of a page management memory.

FIG. 3 is a diagram illustrating a data flow of the printing apparatus according to the embodiment.

FIG. 4 is a flowchart illustrating a reception process.

FIG. 5 is a flowchart illustrating a page data creation process.

FIG. 6 is a flowchart illustrating a pattern data generation process.

FIG. 7 is a flowchart illustrating an operation of an image forming unit.

FIG. 8 is a flowchart illustrating a pattern data transfer process.

FIG. 9 is a diagram illustrating a process of paper jam occurrence.

FIG. 10 is a diagram illustrating a process of paper jam occurrence.

[Explanation of symbols]

 1 Printer 2 I / F Controller 3 Engine Controller 4 CPU 5 ROM 6 RAM 7 Receive Buffer 8 Page Buffer 9 CG 10 Frame Memory 11 Host I / F 13 Video I / F 14 Printhead 15 Paper Ejection Sensor 16 Photoreceptor Drum 17 Transfer device 18 Paper feed cassette 19 Standby roll 20 Fixing roll

Claims (1)

[Claims] 1. A printing apparatus for generating pattern data to be printed on an image memory based on print information input from a higher-level device and performing print processing according to the pattern data, generating pattern data from the print information, Image data generating means for developing in the image memory, time measuring means for measuring the time required from the start of developing the pattern data for one page of paper to the end of developing in the image memory, and a printing unit for printing the data in the image memory. Data transfer means for transferring data to the image memory, and the data transfer means has an erasing mode for erasing an area of the image memory where the data is read and a holding mode for holding the data as they are in the transfer processing. A printing process characterized by performing a transfer process in the holding mode for page data that has been timed by the timekeeping means for a predetermined time or longer. apparatus.