JP3034540B2 - Printing system and its error recovery method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention comprises a host computer and a printer,
The host computer can communicate with each other, the host computer sends a command to the printer, and the printer performs printing in accordance with the content of the command sent from the host computer, in particular, a laser beam printer, a wire dot printer, etc. And error recovery such as a paper jam error that has occurred in the printer.

[Conventional technology]

Conventionally, as described in Japanese Patent Application Laid-Open No. 60-257262, a printer has a command for holding a print command sent from a host computer until it confirms the completion of paper ejection, which is a normal end of the print processing of the print command. The buffer has been prepared for the command of the maximum number of sheets to be simultaneously printed in the printer (hereinafter, simply referred to as the maximum number of held sheets). When a paper jam error or the like occurs, the error recovery is performed by reading the print command after the error occurrence from the command buffer after the error recovery and printing again.

[Problems to be solved by the invention]

In the above-described related art, in order to hold the print command until the completion of the paper ejection that is the normal end of the print processing of the print command is confirmed, a command buffer capable of storing the print command of the maximum number of sheets is stored when a paper jam error or the like occurs. Had to be prepared just for error recovery. In addition, at this time, the required command buffer capacity is considerable and the cost is high.

For example, in a laser beam printer having a printing speed of 20 sheets / minute, about 20 sheets are simultaneously involved in the printing process, so the maximum holding number is about 20 sheets. In addition, the capacity of a print command per sheet is about 1 megabyte when one page of A4 size is transmitted as image data having a density of 300 dots / inch. Therefore, in this case, the capacity of the command buffer dedicated to the error recovery required about 20 megabytes.

SUMMARY OF THE INVENTION It is an object of the present invention to solve the above-mentioned problems of the related art, improve the reliability and operability of a printing system, and reduce costs.

[Means for solving the problem]

The following invention is disclosed as a means for achieving the above object.

According to a first aspect of the present invention, print processing resumed after error recovery of a printer is performed by using a serial number for each print page in a print command for instructing a printer to print contents and the like by a host computer, and using the serial number of the print page. The printer and the host computer each manage a print command using the serial number of the print page, and the printer reports the serial number of the print page being printed to the host computer when an error occurs. And retransmitting a print command after the page indicated by the serial number of the print page reported from the printer after the error recovery to the printer, thereby performing the error recovery method of the printing system.

According to a second aspect of the present invention, there is provided a print command for instructing a printer on a print content or the like by a host computer, assigns a serial number to each print page, and uses the serial number of the print page to manage the print command. An error management table that stores at least error information having an error type and a serial number of a print page being printed;
A printer having means for reporting the error information to the host computer when an error occurs, and abnormal processing control means for controlling each process when the error occurs, and means for managing print commands using serial numbers of print pages Means for inquiring the printer of an error state by a command, and means for retransmitting a print command after the serial number of a print page included in the error information reported from the printer to the printer after error recovery. And a printing system comprising:

In each of the above inventions, the host computer may include means for instructing initialization of the printer after the error recovery and before resending the print command, or in each of the above inventions, the printer may determine that the cause of the error has been eliminated. Means for initializing itself at the time of detection by the printer, and for notifying the host computer that the print command was unacceptable in response to reception of the print command before initialization after eliminating the cause of the error; Preferably, at least one of the two means is provided.

When an error occurs during printing of a plurality of copies, the printing system according to the present invention reports, to the host computer, information on the number of copies remaining to be printed on the page in addition to the serial number of the print page being printed. Means for transmitting, to the printer after error recovery, a print command including a print instruction for the remaining number of copies of the print reported by the printer for the page indicated by the serial number of the print page reported by the printer And a host computer having the following.

In the above embodiments, the host computer assigns a serial number to a print command for instructing a printer on the contents to be printed and the like on a print page basis, and manages the print command using the serial number of the attached print page. Is provided to each of the printer and the host computer.

[Action]

According to the first aspect, the printer reports to the host computer the serial number of the print page that was being printed when the error occurred.
The printer resends print commands following the page indicated by the serial number of the print page reported by the printer. The printer performs printing after the serial number of the print page in accordance with the retransmitted print command. That is, the printing process resumes and continues.

In the printing system according to the second aspect of the invention, in order to perform printing, the host computer transmits a print command instructing a print content to the printer.

In order to manage the print commands, the print commands are divided into print pages and serial numbers are assigned. The serial numbers are referred to as print page serial numbers.

The serial number of the print page in the printer is assigned by increasing the number based on the first page of the print document. Update of the serial number of the print page is performed when it is confirmed that the printed sheet has been discharged from the printer.

If an error that requires retransmission of a print command from the host computer to the printer, such as a paper jam error, occurs in the printer, the printer prints the error type in the error management table and the print page that was printing when the error occurred. Stores error information such as page serial numbers.

The printer notifies the host computer of the occurrence of the error by using an error occurrence notifying unit.

The host computer checks the error status.
A printer status inquiry command is transmitted to the printer. After receiving this command, the printer reads the error information from the error management table, and reports the printer status to the host computer using the printer status reporting means.

The host computer analyzes the information from the printer and notifies the user.

After the user eliminates the cause of the error, the printer status is initialized.

After the initialization of the printer is completed, the host computer retransmits a print command subsequent to the serial number of the print page sent from the printer to the printer.

The printer that has received the command resend continues printing from the time when the error occurred. That is, the printing process resumes and continues.

The host computer issues an instruction to initialize the printer after error recovery and before resending the print command.
Send to printer.

The printer that has received the command to instruct the printer to initialize initializes its own state.

According to the above operation, the printer can be initialized from the host computer after the error recovery and before the retransmission of the print command.

Alternatively, the printer detects that the cause of the error has been eliminated, initializes itself, and cannot receive the print command before receiving the print command before the initialization after eliminating the cause of the error. This is reported to the host computer, and the host computer receiving the report resends the print command reported as unacceptable.

With the above operation, the print command can be retransmitted correctly after the initialization of the printer.

If an error occurs while printing multiple copies,
The printer reports, to the host computer, information on the number of copies remaining to be printed on the page, in addition to the serial number of the print page being printed.

After the recovery from the error, the host computer transmits a print command including a print instruction of the number of remaining copies of the print reported by the printer to the printer with the serial number of the print page reported by the printer.

The printer that has received the print command performs printing in accordance with the received print command. That is, the printing process resumes with respect to the number of copies.

〔Example〕

 Hereinafter, a first embodiment of the present invention will be described.

 FIG. 1 shows the configuration of this apparatus.

This device includes a host computer 100 and a printer 110.

The host computer 100 includes a communication control unit 101, a command control unit 102, a storage unit 103, a display unit 104, and an input unit 105
Consists of

The communication control unit 101 includes a printer controller 111 described later.
Control communication with The command control unit 102 analyzes and executes data transmitted and received by communication. Storage unit 103
Stores a print command. The display unit 104 displays a message. The input unit 105 receives an input from a user.

The printer 110 includes a printer controller 111, a printer engine 112, and the like.

The printer controller 111 includes a communication control unit 113, a command control unit 114, a drawing control unit 115, an abnormality processing control unit 116, a page buffer 117, a printer engine control unit 118, a timer control unit 119, and an error management table 120. You.

The communication control unit 113 controls communication with the host computer 100. The command control unit 114 analyzes and controls communication commands and the like.

The drawing control unit 115 performs a drawing process in accordance with the print command received from the command control unit, generates characters, figures, and the like as dot image data on the page buffer 117, and sets the page buffer 11 on which the drawing has been completed.
The print process for 7 is instructed to the printer engine control unit 118.

The abnormality processing control unit 116 performs processing when an abnormality occurs using the error management table 120 that stores the abnormality information.

The timer control unit 119 performs timer control such as a discharge completion monitoring timer.

The printer engine control unit 118 converts the dot image data drawn on the page buffer 117 into a signal in a format that can be received by the printer engine unit 112, and outputs the signal to the printer engine unit 112.

The printer engine unit 112 performs printing on paper using an electrophotographic printing mechanism or a wire dot printing mechanism according to the input signal.

A command control unit 102 of the host computer 100,
The drawing control unit 115 of the printer controller 111 has print page management units 106 and 121 for managing serial numbers assigned to each print page.

FIG. 2 shows the operation flow on the printer side, FIG. 3 shows the operation flow on the host computer side, and FIG. 4 shows the entire communication sequence.

Host computer 100 and printer controller 111
The print command is divided into print pages, a serial number is assigned to each page, and the print commands are managed by the print page management means (106, 121) using the serial numbers. The serial number is sequentially increased with the first page of the print document set to 0. This serial number is called a print page serial number.

The printer controller 111 increases the print page serial number each time the discharge is completed (sequences 139 and 140). The details of the procedure for confirming the completion of paper ejection will be described later.

When receiving a print instruction from the user (step 306), the host computer 100 reads a print command from the storage unit 103 (step 322), and the printer controller 111
(Step 323).

The printer controller 111 receives the command (step 201), and if it is a print command (step 218), starts the printing process (step 219). Printing process (step 2
In step 19), processing such as detection of the completion of paper ejection and a page buffer read request from the drawing control unit 115 to the printer engine control unit is performed.

If a paper jam error has occurred in the printer engine unit 112, the printer engine unit 112 notifies the printer engine control unit 118 of that (step 220).

After receiving the notification, the printer engine control unit 118 checks the error type, and then notifies the abnormality processing control unit 116.

The abnormality processing control unit 116 requests the drawing control unit 115 to interrupt the drawing process and the printing process (step 20).
2). The error management table 120 stores the print page serial number of the print page being printed at the time of the error occurrence, the fact that the error type is a paper jam error, and the like (step 203).

The command control unit 114 creates the content of the error occurrence notification, and issues a transmission request to the communication control unit 113.

Upon receiving the transmission request, the communication control unit 113 transmits this notification content to the host computer 100 (step 204,
Sequence 402).

The communication control unit 101 of the host computer 100 receives the error occurrence notification (Step 313), and
Notify 02.

When receiving the error occurrence notification, the command control unit 102 creates a printer status inquiry command to confirm the error content, requests transmission to the communication control unit 101, and transmits this command (step 302, sequence 403).

When the communication control unit 113 of the printer controller 111 receives the printer status inquiry command (step 205), the command control unit 114 creates the response data to the printer status inquiry command.
Read error information from.

After the creation of this response data (step 206), a printer status report is transmitted from the communication control unit 113 to the host computer (step 207, sequence 404).

The communication control unit 101 of the host computer 100 notifies the received report to the command control unit 102 (step 303).

When it is determined that a paper jam error has occurred, the command control unit 102 causes the display unit 104 to display that a paper jam error has occurred (step 313).

Thereafter, an error occurs (step 301), and an instruction from the user is waited for (step 320, sequence 40).
8).

The user removes the cause of the error by removing the jammed paper from the printer (sequence 410), and then gives an error recovery instruction from the input unit 105 (sequence 40).
9).

The host computer receives instructions from the user (step
According to 320), a cancel command is created by the command control unit 102 to enable the printer controller 111 to print, and transmitted from the communication control unit 101 (step 321, sequence 405).

In the case of an error requiring a command retransmission such as a paper jam error, the error processing is performed. If any other error occurs (step 324), appropriate error processing corresponding to the error that has occurred is performed (step 325).

When the communication controller 113 receives the cancel command, the printer controller 111 notifies the command controller 114 (step 211).

The command control unit 114 executes a cancel command. That is, in order to initialize the printer state, the drawing control unit 115 is caused to clear the page buffer 117 (step 212).

Subsequently, the command control unit 114 creates a cancellation end report to notify the host computer 100 that the cancellation has been completed, and causes the communication control unit 113 to transmit the report (step 213, sequence 406). Then, after transmission, the printer is set in a printable state (step 214).

After receiving the cancellation end report by the communication control unit 101 (step 308), the host computer 100 is included in the printer status report (sequence 404) in order to reprint from the page after the paper jam error occurred. Storage unit 103 stores the print command after the print page serial number
(Step 311), and then sends it to the printer controller 111 (step 312, sequence 407).

The printer controller 111 resumes printing according to the received print command (step 218) (step 21).
9).

As a result, printing is performed from the page after the page where the paper jam error has occurred.

According to this embodiment, even when a paper jam error occurs in the printer, printing after the occurrence of the error can be resumed without providing a command buffer dedicated to error recovery in the printer. Therefore, the cost of the printing system can be reduced, and the reliability and operability can be improved.

Note that, as described above, a description will be given of a discharge completion confirmation procedure required to update the serial number of a print page.

FIG. 5 shows an example of an operation sequence for confirming discharge completion.

With reference to this figure, a procedure for confirming the discharge completion of the page of each print page serial number will be described.

The drawing control unit 115 instructs the printer engine control unit 118 to print the data in the page buffer 117 to the printer engine unit 112.
When a readout instruction (hereinafter simply referred to as a page buffer readout instruction) is issued (sequences 130 and 133), a request is made to the timer control unit 119 to start the discharge monitoring timer (sequences 131 and 134).

The printer engine control unit 118 includes the printer engine unit 1
Send drawing data to 12 (sequences 137 and 13
8).

When the printer engine unit 112 receives the drawing data, it performs printing, and then discharges the paper (sequences 139 and 14).
0).

After the monitoring time has elapsed, the timer control unit 119
19 notifies the drawing control unit 115 of the end of the monitoring time (sequence 1
32,135,136).

The drawing control unit 115 issues a page buffer read request to the printer engine
If there is no abnormality within the time supposed to take until the sheet 12 is discharged, it is determined that the sheet has been discharged, and the print page serial number is increased (sequences 141, 142, 143).

The monitoring time differs depending on the print paper size, and is set when requesting the timer control unit 119 to start the discharge monitoring timer.

 Next, a second embodiment of the present invention will be described.

The operation flow of the printer controller 111 is shown in FIG.
FIG. 7 shows an operation flow of the host computer 100, and FIG. 8 shows an entire communication sequence.

In this embodiment, the printer itself monitors an error state without using the cancel command used in the first embodiment,
When the paper jam error is eliminated, the initialization is automatically performed and a printable state is set.

The printer controller 111 is connected to the host computer 100
After sending a printer status report to
4), monitor the error status (steps 217 and 60)
1). Example 1 when detecting that the cause of the error has been eliminated
Similarly, the current state is initialized (step 602), and the printable state is set (step 603).

If the error that has occurred does not require command retransmission (step 609), another error processing is performed (step 610).

After an error recovery instruction from the user (step 320), if an error requires a command retransmission (step 324), the host computer 100 reads out a print command subsequent to the print page serial number from the storage unit 103 (step 31).
1) and sends it to the printer controller 111 (step 70)
5,806).

When the printer controller 111 receives the print command, if the cause of the error remains or the initialization is not completed (step 604), the printer controller 111 transmits a command refusal report to the host computer (step 605, sequence 801). ).

Upon receiving the command refusal report (step 702), the host computer 100 waits for a certain period of time and resends the print command (steps 703 and 705, sequence 80).
Four).

If there is no error when the print command is received and the initialization has been completed (step 60)
In 4), after the command reception report to the host computer 100 that the command has been normally received, printing is restarted (steps 607 and 608, sequence 805).

In the present embodiment, in addition to the effect of the first embodiment, there is an effect that the error recovery sequence can be simplified because the initialization of the printer state by the cancel command becomes unnecessary.

 Next, a third embodiment of the present invention will be described.

The operation flow on the printer side will be described with reference to FIGS. 2 and 6, and FIG. 7 showing the operation flow on the host computer side.

A description will be given of a case where an error that requires retransmission of a print command from the host computer 100 to the printer controller 111, such as a paper jam error, occurs in multi-page printing for printing a plurality of pages.

In the first and second embodiments, the error information stored in the error management table 120 by the printer controller 111 at the time of occurrence of an error includes the remaining number of print copies indicating the number of remaining multi-page print copies that have not been printed at the time of occurrence of the error. Is added to the error information of the present embodiment.

In multi-page printing, the host computer
The print command is used to indicate the total number of copies for each print page. For each print page, the printer
Print the same content for the total number of copies.

If a paper jam error occurs during multi-page printing, the printer controller 111 sends the error management table 1
In step 20, the error type, the print page serial number, and the number of remaining copies are calculated and stored as error information (step 20).
3). Here, the remaining number of copies is a numerical value obtained by subtracting the current number of printed pages from the total number of copies for the print page in which the error has occurred.

The printer controller 111 is connected to the host computer 100
Then, an error occurrence notification is transmitted to notify that an error has occurred (step 204).

Upon receiving the error notification (step 301), the host computer 100 transmits a printer status inquiry command to the printer controller 111 (step 302).

The printer controller 111 that has received the printer status inquiry command (step 205) sends the error management table 12
From 0, the error information of the error type, the print page serial number, and the remaining number of copies is read (step 206), and after creating response data, a printer status report is transmitted to the host computer 100 (step 207).

The host computer 100 reads out the error information included in the received printer status report (Step 306). It is determined from the error type of the error information that a paper jam error has occurred, and the print command of the page to start resuming printing is determined from the print page serial number. Also, the total number of prints for the page of the next print page serial number to be instructed to the printer is determined from the remaining number of prints.

After the initialization of the printer controller 111 is completed (steps 602 and 603), the host computer 100 specifies the remaining number of copies to be printed in multi-page printing based on the error information, and issues a print command to the printer controller 11 (step 602).
Send to 1 (step 705).

After receiving this command (step 218), the printer controller 111 resumes printing (step 60).
8).

As a result, printing from the page after the error page can be performed by multi-page printing.

Also, in normal printing, the operation is performed without any trouble by assuming that the number of copies of multi-page printing is one.

Further, although the number of remaining copies is stored in the error information, this may be used as the current number of copies indicating the number of copies completed before the error occurred.

When the current number of prints is used, the host computer 100 calculates the remaining number of prints by subtracting the current number of prints from the total number of prints.
Instruct

This embodiment has the advantages of the first and second embodiments,
There is an effect that error recovery can be performed even for an error at the time of multi-page printing for printing a plurality of one page.

FIG. 9 shows a list of commands used in the first, second, and third embodiments. In the figure, 901 is an error occurrence notification, 902 is a printer status inquiry command, 905 is a printer status report, 903 is a cancel command, 904 is a cancel processing end report, 906 is a print command, 907 is a command reception refusal report, and 908 is a command This is a reception report.

In the first embodiment, 901,902,903,904,905 and 906 are used, and in the second embodiment, 901,902,905,906,907 and 908 are used.
It was used.

The third embodiment can be realized by using any of the commands of the first embodiment and the second embodiment.

902, 903 and 906 are commands transmitted from the host computer 100 and received by the printer controller 111, 9
01,904,905,907 and 908 are the printer controller 111
Is transmitted and received by the host computer 100. In the first embodiment, 902, 905 and 903, 904 are a paired sequence, and the reports for the commands 902, 903 are 905 and 903.
904. In the second embodiment, 902,905 and 906,907,90
8 is the paired sequence and 90 for the command 902
5, Reports for the command 906 are 907,908.

In the above embodiment, the report is used as the response data to the command. However, the report may be realized by using the command instead of the response.

Further, the present invention can be similarly applied to an error other than a paper jam as long as the error can be recovered by resending the print command from the host computer to the printer.

For example, a door open error when the cover of the printer engine unit 112 is opened during printing, a page buffer parity error when a parity error is detected while reading data from the page buffer 117 to the printer engine unit 112, and the like. Applicable to

When an error occurs, the print controller 111 transmits an error occurrence notification (sequence 402) to the host computer 100 to notify the host computer 100 that the error has occurred. In step (3), a printer status inquiry command (sequence 403) transmitted from the host computer 100 to the printer controller 111 by reporting the error information.
The sequence of the printer status report (sequence 404) transmitted from the printer to the host computer 100 may be omitted.

In the second embodiment, after the printer controller has completed the initialization processing (steps 602 and 603), the printer controller transmits a command acceptable command to the host computer 100,
In response to this, the host computer 100 may start the retransmission of the print command, thereby realizing the present invention.

Each part in FIG. 1 includes a microprocessor, a RAM,
It can be realized using OM, LSI, logic IC, electrophotographic printing mechanism, wire dot printing mechanism, etc.

〔The invention's effect〕

According to the present invention, the recovery when a printer error occurs is not performed by the printer alone, but is performed by the workstation (host computer) after the error recovery by resending the print command of the unfinished printing. Print command sent from
It is not necessary to hold the print command until it confirms the discharge completion, which is the normal end of the print processing of the print command. That is, in the printing system according to the present invention, the print command need only be held until the drawing processing is completed.

Generally, it takes about three times or more time to complete the drawing process until one page is discharged. Therefore, the printing system according to the present invention reduces the amount of the print command buffer to about one third of the conventional size. It can be: Therefore, there is an effect that the cost of the printing system can be reduced and reliability and operability can be improved.

[Brief description of the drawings]

FIG. 1 is a block diagram showing an apparatus configuration of the present invention, FIG. 2 is a flowchart showing a processing procedure on the printer side of the first embodiment, and FIG. 3 is a processing procedure on a host computer side of the first embodiment. FIG. 4 is a sequence diagram showing a communication procedure between the printer and the host computer of the first embodiment, FIG. 5 is a sequence diagram showing a paper discharge confirmation procedure in the printer engine unit 112, and FIG. , Second
FIG. 7 is a flowchart showing the processing procedure on the printer side of the embodiment and the third embodiment, FIG. 7 is a flowchart showing the processing procedure on the host computer side of the second embodiment and the third embodiment, and FIG. FIG. 9 is a sequence diagram showing a communication procedure between the printer and the host computer of the example, and FIG. 9 shows commands and commands for performing communication between the printer and the host computer of the first, second, and third embodiments. FIG. 100 host computer, 101 communication control unit, 102 command control unit, 106 print page management procedure, 110 printer, 111 printer controller, 112 printer engine unit, 113 communication control unit, 114 command control unit , 115 ...
Drawing control unit, 116: abnormality processing control unit, 117: page buffer, 118: printer engine control unit, 120: error management table, 121: print page management unit,

──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Toshiyuki Nakajima 292 Yoshida-cho, Totsuka-ku, Yokohama-shi, Kanagawa Prefecture Within Hitachi Micro Software Systems Co., Ltd. (72) Inventor Tadahiko Aso 292 Yoshida-cho, Totsuka-ku, Yokohama-shi, Kanagawa Stock (72) Keiichi Nakane, Inventor Keiichi Nakane 292 Yoshida-cho, Totsuka-ku, Yokohama-shi, Kanagawa Prefecture, Japan Microelectronics Equipment Development Laboratory, Hitachi, Ltd. (56) References JP-A-63-37420 (JP, A) JP-A-64-23323 (JP, A) JP-A-1-251224 (JP, A) JP-A-1-227168 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) B41J 29/46 B41J 29/38 G06F 3/12

Claims (2)

(57) [Claims] An error recovery method for a printing system comprising a host computer and a printer capable of communicating with each other, wherein the host computer transmits a print command stored in a storage unit to the printer, and transmits the print command to the printer. When the printer receives the print command, the printer divides the print page into units, assigns a serial number to each print page unit, and generates dot image data according to the print command. Performing the printing process of the dot image data, if an error that requires retransmission of a print command occurs, the printer reports the serial number of the print page that requires retransmission to the host computer, and after error recovery, the host computer The print command managed by the print page unit An error recovery method for a printing system, wherein a print command subsequent to a reported print page number is read from the storage unit and retransmitted to the printer. 2. A printer comprising a host computer and a printer capable of communicating with each other, wherein the host computer sends a print command to the printer, and the printer
In a printing system that executes printing in accordance with the content of the print command transmitted from the host computer, the printer separates the print command into print pages and assigns a serial number to each of the divided print pages. A management unit, an error information management table that stores error information having a serial number of a print page that requires retransmission when an error that requires retransmission of the print command occurs, and the content stored in the error information management table is A report unit for reporting to the host computer, wherein the host computer stores the print command; a management unit that manages the print command in print page units; and a storage unit that is stored in the storage unit. Of the printer after recovery from the error Printing system; and a retransmission means for reading resend the page after the print command indicated by the serial number of print pages included in the reported error information from stage from the storage means using said management means.