JP2718730B2 - Printing system - Google Patents

Description

The present invention relates to a host computer such as a personal computer and a workstation, and a laser beam printer.
The present invention relates to a printing system to which a printing device such as a wire dot printer is connected.

[Conventional technology]

As a conventional printing system, a host computer and a printing device are connected via a SCSI interface (ANSI X3, 131-1986)
FIG. 2 shows an example of a system connected by using.

In the system shown in FIG. 2, communication between the host computer 10 and the printing apparatus 11 is executed in the following procedure (see FIG. 3).

(1) In the initial state, the state of the SCSI bus 15 is the bus free phase.

(2) Bus Free Phase In the arbitration phase, the host computer 10 asserts the bus arbitration right by using the arbitration unit 133, and becomes the initiator.

(3) In the selection phase, the host computer 10 uses the selection unit 134 to select the printing device 11 as a target.

(4) In the information transfer phase, the following (i) to (iv)
Follow the steps in (I) to (iv) are called a command phase, a data phase, a status phase, and a message phase, respectively.

(I) The host computer 10 transmits one SCSI command to the printing apparatus 11 using the initiator function unit 135, and gives an instruction to the printing apparatus. The SCSI command, which is sometimes simply referred to as a command hereinafter, is received by the printing apparatus using the target function unit 145.

(Ii) Subsequently, data transmission or reception is performed using 135 and 145 according to the type of command. The data transmission is used for transmitting print data and the like, and the data reception is used for receiving response data to an inquiry from the host computer to the printing apparatus. Some commands do not send or receive data.

(Iii) Subsequently, the command execution status is returned from 145 to 135 as the status.

(Iv) Subsequently, a message is sent from 145 to 135 to report that the processing of the -command by the target is completed. As a result, the state of the SCSI bus 15 becomes the bus free phase again.

Hereinafter, the procedures of (2) to (4) are repeated. The initiator and the target are defined as follows by the SCSI interface standard. Initiator: other
A SCSI controller that requests the SCSI controller to execute a command.

Target: The SCSI control that executes the commands requested by the initiator.

In the above communication procedure, an instruction to print characters, graphics, etc. on the paper from the host computer 10 to the printing device 11 is given by:
This is performed by transmitting a command such as Print and other data and accompanying data from the print instruction unit 12 using (i) and (ii) of the procedure (4).

Here, when the Print or other command is stored in the command buffer unit 161, it is considered that the execution in the printing apparatus has been completed, and a response to the command including the status and the message is transmitted from 145 to 135. At this time, the content of the status indicates success or failure of storing the command in the command buffer unit 161, and the content of the message indicates completion of the main storage process for one command.

The original processing of the printing apparatus 11 is to read and execute the command in the command buffer unit 161 (hereinafter, this processing is referred to as a delayed command processing, and the command executed once after being stored in the command buffer unit is referred to as a delayed processing command). However, if the response (status or message) is used to notify the end of printing of each page or an error in the delayed command processing, since the response has already been issued, the printing apparatus
It cannot be transmitted from 11 to the host computer 10.

Further, there are the following two printing systems in which the host computer 10 and the printing apparatus 11 are connected by an interface other than SCSI, and an error report from the printing apparatus to the host computer is being attempted.

(A) [System described in JP-A-60-204386] The host computer requests a self-diagnosis from the printing apparatus, and the printing apparatus reports the result.

(B) [System described in JP-A-62-90058] The printing apparatus detects an error and sends it to the host computer.

[Problems to be solved by the invention]

(1) In the print system using the SCSI, 145 to 135
In the phase other than the status transmission to the printer, even if an event such as an error or printing end in the printing device 11 is detected,
There is no means for asynchronously reporting from the printing device to the host computer. Even in the status transmission phase, as described above, the status cannot be used to transmit an error detected during execution of the delayed command processing or the end of page printing to the host computer. As a result, the host computer cannot keep track of the latest status of the printing device, such as errors and printing completion, and cannot effectively control the printing device. Further, the printing device cannot receive an appropriate instruction based on the latest status from the host computer. There was a point.

In a printing apparatus such as a print server or a common printer, which is used in a place where the print requester is away from the print requester, there is a risk of errors such as consumption of consumables such as paper and toner and heating of a laser beam printer fixing device heater. It is necessary to report such errors to the host computer as soon as the printing apparatus detects them, but this is not possible with the printing system.

(2) In the system described in Japanese Patent Application Laid-Open No. 60-204386, even if an event such as an error or printing end occurs in the printing apparatus, unless the host computer requests the printing apparatus to perform self-diagnosis, the event is transmitted to the host. There was a problem that it could not be transmitted to the computer.

(3) In the system described in Japanese Patent Application Laid-Open No. 62-90058, a method of asynchronously reporting various events occurring in the printing apparatus from the printing apparatus to the host computer, particularly a method of asynchronously reporting using SCSI communication Had a problem that it was not taken into account. Furthermore, since only a very small part of the events in the printing apparatus, such as errors detected by the error detection unit, can be transmitted to the host computer, the host computer cannot effectively control the printing apparatus. Was.

SUMMARY OF THE INVENTION An object of the present invention is to solve the above-mentioned problems of the conventional system, and to send various events such as an error occurring in a printing apparatus, completion of page printing, a change in a communicable state from a host computer, etc., from the printing apparatus to the host computer. Immediate reporting to increase the throughput, security, reliability and operability of the printing system.

[Means for solving the problem]

In order to achieve the above object, the present invention has the following configuration. A printing system, comprising a host computer and a printing device, and a communication path connecting the host computer and the printing device, wherein a printing command that instructs printing to the printing device from the host computer is transmitted through the communication path. A polling command section for issuing a polling command for confirming the presence / absence of a state change in the printing apparatus asynchronously with the transmission of a command sequence for use in the printing apparatus. A polling response unit for storing, and the state change stored in the command response unit is:
Due to the state change, (1) a state in which the printing device and the host computer can communicate, (2) a state in which the printing device and the host computer cannot communicate, and (3) a user of the printing system intervenes in the printing device. The printing apparatus and the host computer are classified as a hold state in which communication can be returned to a communicable state, and in response to a polling command, the presence or absence of a state change is transmitted according to the contents stored in the polling response unit. If the command has been received, the printing apparatus transmits a command for inquiring about the state change stored in the polling response unit. The status is transmitted to the host computer, and the host computer receives the received status (1) to (3). A command instructing a printing according to the state and transmits to the printing apparatus.

[Action]

Each part in the printing device (host communication part, command processing part,
Printer control unit, etc.)
That is, upon detecting an event such as an error, an end of page printing, an empty command buffer, or a change in a communicable state (hereinafter referred to as a host-printer communication state) from the host computer, the contents of those events are immediately transferred to the polling response data section. Set to

On the other hand, in the host computer, the polling unit performs the following procedure asynchronously with the command transmission procedure for document printing by the print instruction unit, and grasps the status change in the printing apparatus.

(1) A polling command is issued from the host computer to the printing apparatus at a polling cycle with a sufficiently short time interval to check whether there is a report content from the printing apparatus.

(2) The printing device responds to the host computer whether or not there is a report.

(3) When the host computer receives the information indicating that there is nothing from the printing device, the host computer ends the current polling procedure.

(4) When the host computer receives the notification from the printing apparatus, the host computer performs the following procedure.

(I) The host computer issues a report content inquiry command (also called a printer status inquiry command) to the printing device in order to know the content of the report from the printing device.

(Ii) The printing device transmits the report content as response data to the host computer.

(Iii) The host computer analyzes the content of the report from the printing device and performs a corresponding process.

As described above, the polling section and the polling response data section are provided in each of the host computer and the printing apparatus, and by operating them, various status change events in the printing apparatus are immediately reported from the printing apparatus to the host computer. Can optimally control itself and the printing apparatus according to the contents of the report, so that the throughput, security, reliability, and operability of the printing system can be improved.

〔Example〕

Hereinafter, the first embodiment of the present invention will be described with reference to the configuration example of FIG.

This configuration example includes a host computer 10, a printing device 11, and a communication path 15. Host computer 10 and printing device 11
Each have a printer communication unit 13 and a host communication unit 14,
By controlling 13 and 14 respectively, they communicate with each other through a communication path 15.

The printer communication unit 13 in the host computer 10 has a command transmission unit 131 and a response reception unit 132. The host communication unit 14 in the printing apparatus 11 includes a command reception unit 141 and a response reception unit 142.
Having.

The printing device 11 includes a command processing unit 16, a print input buffer unit 17, a printer control unit 18, a printer engine unit in addition to the unit 14.
19 has a command buffer unit 161 and a delayed command processing unit 164 therein.

The host computer 10 has a print instruction unit 12 in addition to the print instruction unit 13. The print instruction unit 12 issues a document print command to the printing device 11 using the command transmission unit 131.

The printing device 11 stores the command for document printing transmitted from the host computer 10 in the command buffer unit 161 in 16, and also transmits response data indicating success / failure of the storage process to the response transmission unit 142. To send it to the host computer 10.

The host computer 10 and the response receiving unit 132 receive the response data.

The command stored in the command buffer unit 161 is divided into a command for drawing and a command for printing, and is executed by the delay command processing unit 164.

When a command to instruct drawing is executed, characters and figures are drawn as dot images on the print input buffer unit 17. When a command to instruct printing is executed, the printer control unit 18 is activated. The printer control unit 18 reads out the contents (dot image data) of the print input buffer unit 17 for which the drawing has been completed, and transmits it to the printer engine unit 19. The printer engine unit 19 performs printing on paper using an electrophotographic printing mechanism or a wire dot printing mechanism in accordance with the input dot image data. Here, it is desirable to prepare a bitmap memory for one or more sheets of paper in the print input buffer unit to improve the throughput of the printing system. When a memory for one page or more is prepared, the print input buffer unit is also called a page buffer memory unit.

A feature of the present invention is that a polling unit 20 is provided in the host computer 10 and a polling response data unit is provided in the printing device 11.
146 are provided.

The polling response data unit 146 includes an error, a page printing end, a command buffer empty, a host printer communication state (second embodiment) in the delay command processing unit 164, the printer control unit 18, and other units in the printing apparatus. In FIG. 4, which will be described in detail in FIG. 4, the state of the printing apparatus is also changed. That is, the polling response data section 146
Then, the latest event in the printing device 11 is set immediately when it occurs and is detected.

FIG. 4A shows the data format of the polling response data section 146. FIG. 4 (b) shows the contents of each item in FIG. 4 (a).

The polling unit 20 performs the processing described as (1) to (4) in the section of “action” asynchronously with the transmission procedure of the document printing command by the print instruction unit 12. The above polling procedure is shown in FIG. FIG. 5 (a) shows the procedure when there is no report content, and FIG. 5 (b) shows the procedure when there is report content.

In the polling procedure of FIG. 5, (b) the report content itself is added to (a) the presence or absence of the report content in the response data to the polling command, and (a) and (b) are collectively printed. The information may be transmitted from the device 11 to the host computer. This makes it possible to omit the procedure for issuing a report content inquiry command from the host computer 10 to the printing device 11 when there is a report content shown in FIG. 5 (b).

Each part of FIG. 1 includes a microprocessor, a RAM, a ROM, an LSI,
It can be realized using a logic IC, an electrophotographic printing mechanism, a wire dot printing mechanism, or the like.

According to the present embodiment, the status change event in the printing apparatus is reported from the printing apparatus to the host computer, and the host computer can optimally control itself and the printing apparatus according to the content of the report. , Safety, reliability, and operability can be improved.

Next, a second embodiment of the present invention will be described using the configuration example of FIG. FIG. 6 is obtained by adding an abnormality processing unit 61, a panel control unit 62, a printing apparatus status table 63, and a cancel processing unit 64 to FIG.

When an error is detected in each unit in the printing apparatus 11, the error processing unit 61 is started using the error number as an input parameter. From the abnormality processing unit 61, each unit in the printing apparatus (host communication unit 14, command processing unit 16, delay command processing unit 164, printer control unit 18, printer engine unit 19, panel control unit 6)
2, etc.) can be handled in common.

The panel control unit 62 is provided to control a user panel that controls a man-machine interface between the printing apparatus and the user. 62 is a host computer
The communication state between the printer 10 and the printing apparatus 11 (hereinafter, abbreviated as a host printer communication state) is displayed and input. here,
As the host / printer communication state, communication possible (online), communication impossible (offline), and hold (user intervention request) are provided. The hold state corresponds to an error of a type that can be returned to a normal state by a user's intervention operation to the printing apparatus, such as no paper or toner. In this state, the host computer must not send the delay processing command to the printing device. The printing device ignores it even if it is sent. In this state, the only commands that can be passed from the host computer to the printing apparatus are commands that are called immediate processing commands and that are not stored in the command buffer unit 164 but are immediately executed in the host communication unit 15 in the printing apparatus.

The cancel processing unit is provided for performing a cancel process (clearing all buffer data in the printing apparatus). The instruction of the cancel processing is issued by either a command transmission from the host computer to the printing apparatus or an input from the user panel.

The printing device status table is configured as a sequence of (a) error codes and (b) host / printer communication status. In (a), an error number detected in each unit in the printing apparatus 11 is written. The writing to (b) is performed by the abnormality processing unit 61, the panel control unit 62 and the like, and the host communication unit 14 and the panel control unit 62 in the printing apparatus are referred to while referring to the contents of (b).
To work.

In the configuration of FIG. 6 described above, the state change shown in FIG.

The report content code (see FIG. 4) in the polling response data section 143 is determined to roughly classify the contents of the polling response data section. When this code is 0 (all bits 0),
There are no reports. When the sixth bit of this code is 1, the host computer 10 reads out the current page number in the report content and specifies the page that has been printed. In this printing system, the print end page is managed by the following two parameters as described above.

Page No. (Each physical page that constitutes a document
The serial number with the leading number set to 0) The current number of copies for each page (0 to the value of the total number of copies)
I went in 1. The processing can be performed by the host computer 10, and the contents can be included in the print instruction command sequence and transmitted to the printing apparatus 11. If the 0th bit of this code is 1,
The host computer 10 reads out the error code in the report content and specifies the error content. Depending on the error code, the paper size request, paper source position,
The retransmission start page position is also read out and used in error processing. Among these, the paper size request and the paper feed unit position indicate to the user in the processing of the paper-out error by the host computer 10 or the printing device 11 that "the user is requested to replenish the specified paper size at the specified paper feed unit position. Used for.

The retransmission start page position is used by the host computer 10 when the error code requires a retransmission of the print instruction command such as a paper jam or a data parity error from the host computer 10.
The retransmission start page position is composed of a set of the page number and the number of remaining copies. Here, the remaining number of copies is a numerical value obtained by subtracting the current number of prints from the total number of prints for each page (managed by the page number).

If the report content occurs multiple times during one polling cycle, the corresponding item in the polling response data section 146 is updated for the content other than the error, and the error is additionally written. Errors can be written up to the maximum number (for example, 10).

According to the present embodiment, since all the various events that occur in each unit in the printing apparatus 11 can be reported to the host computer 10, the host computer performs appropriate processing shown in FIG. Treatment can be eliminated.
Further, since the error processing is performed in one place in a unified manner, there is an effect that the capacity of the error processing program can be reduced and its reliability can be improved.

Next, a third embodiment of the present invention will be described using the configuration example of FIG.

This embodiment is different from the first embodiment shown in FIG. 1 in that the communication path 15 is a SCSI bus. Therefore, the printer communication path 13 in the host computer is used for the host computer.
The host communication unit 14 in the printing device was used as the SCSI control unit, and the SCSI communication unit in the printing device was used.

The transmission and reception of the polling command and the report content inquiry command are performed by the initiator function unit 13 in the host computer.
5 and the target function unit 145 in the printing apparatus.

FIG. 9 shows a polling procedure performed by the polling unit 20 in this embodiment. In this procedure, the transmission and reception of the response data in FIG.
Two phases of status transmission and reception, message transmission and reception,
Or (b) three phases of data transmission / reception, status transmission / reception, and message transmission / reception. (A) is used for sending and receiving response data to the polling command,
(B) is used in transmitting and receiving response data to the report content inquiry command. In the case where there is no report content in FIG. 9A, a “GOOD” status is transmitted from the target function unit 145 in the printing apparatus to the initiator function unit 135 in the host computer. If there is a report content in Fig. 5 (b), 145
To 135 to send a "CHECK CONAITION" status.

FIG. 10 shows the functions of the polling command and the report content inquiry command. For the former, the vendor is unique
This is provided as a SCSI command in the present invention. For the latter, the "REQUEST SENSE" command of the SCSI interface standard was used. CDB of both commands (Command Descript
11 (a) and 11 (b) show a SCSI command format called an ion block. The printing device 11 is provided with
In the data transmission for the "SENSE" command, the contents of the polling response data section 143, that is, the report contents are transmitted to the host computer 10 and reported.

Note that the second embodiment can also be realized by using the SCSI interface in the same manner as the third embodiment.

In the present embodiment, since the SCSI interface is used for the communication means between the host computer 10 and the printing device 11, a printing system with a high-speed and standard interface, which is an advantage of SCSI, can be provided.

〔The invention's effect〕

According to the present invention, since various status change events in the printing apparatus are immediately reported from the printing apparatus to the host computer, and the host computer can optimally control itself and the printing apparatus according to the report contents, the throughput of the printing system This has the effect of improving safety, reliability and operability.

[Brief description of the drawings]

FIG. 1 is a block diagram showing the configuration of a first embodiment of the present invention,
2 and 3 are diagrams for explaining the configuration and operation of a conventional printing system, FIGS. 4 and 5 are diagrams for explaining the first embodiment of the present invention, and FIG. 6 is a diagram for explaining the first embodiment of the present invention. FIG. 7 is a block diagram showing the configuration of the second embodiment, FIG. 7 is an explanatory diagram showing the operation of the second embodiment of the present invention, FIG. 8 is a diagram showing the configuration of the third embodiment of the present invention, and FIG. FIG. 10 and FIG. 11 are explanatory diagrams showing the operation of the present invention, and are explanatory diagrams showing functions and formats of SCSI commands used in this embodiment. 10 host computer, 11 printing device, 12 printing instruction unit, 13 printer communication unit, 14 host communication unit, 15 communication path, 16 command processing unit, 17 printing Input buffer section, 18 Printer control section, 19 Printer engine section, 20 Polling section, 131 Command transmission section, 132 Response reception section, 141 Command reception section, 142 Response transmission Section, 146: Polling response data section.

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Keiichi Nakane, Inventor Keiichi Nakane 292, Yoshida-cho, Totsuka-ku, Yokohama-shi, Kanagawa Prefecture Inside the Microelectronics Equipment Development Laboratory, Hitachi, Ltd. Hitachi, Ltd., Kanagawa Plant (72) Inventor Toshiyuki Nakajima 292, Yoshida-cho, Totsuka-ku, Yokohama, Kanagawa Prefecture Hitachi Microsoft Wear Systems, Ltd. (72) Tadahiko Aso 292, Yoshida-cho, Totsuka-ku, Yokohama, Kanagawa Prefecture Shares (56) References JP-A-62-90058 (JP, A) JP-A-63-240147 (JP, A)

Claims (4)

(57) [Claims] 1. A printing system comprising a host computer, a printing apparatus, and a communication path connecting the host computer and the printing apparatus, wherein a command for instructing the printing apparatus to perform printing from the host computer is transmitted through the communication path. A polling command unit that is present in the host computer, issues a polling command to check whether there is a status change in the printing device asynchronously with the transmission of a command sequence for printing instructions, and exists in the printing device. A polling response unit that stores the status change for responding to the polling command, wherein the status change stored in the command response unit is a change in the communication status between the host computer and the printing apparatus. (1) A state in which the printing device and the host computer can communicate with each other. (2) the printing apparatus and the host computer cannot communicate with each other, and (3) the printing apparatus and the host computer can communicate with each other due to an intervention operation of the printing system user to the printing apparatus. Stores a hold state capable of returning to a state, and information indicating a place where printing is interrupted due to an error in the printing apparatus, and transmits the presence or absence of the state change according to the storage content of the polling response unit in response to the polling command. When the host computer receives the status change, the host computer transmits a command for inquiring the status change stored in the polling response unit to the printing device, and the printing device receives the command for inquiring the status change. In this case, the status change (the content stored in the polling response unit) is caused by the (1) to (3). Send or is one of the states to the host computer, the host computer, the received (1) -
(3) The processing according to the state is determined, and as a result of the determination, when reprinting is to be performed, a command for instructing to start printing from the part where the printing stored in the polling response unit is interrupted is transmitted. A printing system. 2. The printing system according to claim 1, wherein the command for instructing printing is a delay processing command stored in a command buffer unit existing in the printing apparatus and an immediate processing not stored in the command buffer. A printing system comprising a command, and in the case of the state (3), the host computer transmits only the immediate processing command. 3. The printing system according to claim 1, wherein the printing system includes a user panel for managing a man-machine interface with a user, and in the case of the state (3), the user panel includes the user panel. A printing system comprising a panel control unit for displaying a user's intervention operation to the printing apparatus. 4. The printing system according to claim 1, wherein the information indicating the place where printing is interrupted due to an error in the printing apparatus is added to the beginning of each physical page constituting the document being printed. A printing system comprising: a page serial number which is a serial number assigned to a page; and a current number of copies which is the number of prints at the time of interrupting printing on each physical page.