JPH1024645A - Image forming device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To enable the checking of information relative to a user error at a host device by transmitting the information on a user error due to which image forming operation need not be interrupted to the host device when such as error occurs. SOLUTION: When a control code received from a host device 4 is a control code for controlling information relative to a user error, a controller 2 interprets whether the control code is relative to the storage of the information relative to the user error into an area for storing the information relative to the user error and decides whether the user error should be stored. Thus the information relative to the user error is sequentially stored in the area for storing the information relative to the user error. A sending format is decided based on the control code, and the controller 2 executes the sending of the information to the host device 4 using the decided sending format. Thus the user can obtain the information relative to the user error generated as described at the host device and dispense with the trouble to check with a remote image forming device.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image forming apparatus such as a printer, a copying machine, a facsimile, and the like.
The present invention relates to an image forming apparatus that is connected to a higher-level device that transmits image information and that forms an image based on the image information.

[0002]

2. Description of the Related Art Conventionally, an image forming apparatus that forms an image based on image information from a host device is known. Errors generated by such an apparatus include the following three forms. Error is possible. First, the first mode is that the image forming operation is interrupted, such as a paper jam (jam), no recording paper, or toner end, but the normal user removes the cause of the error to recover the normal state. Is an error that can occur. In the second mode, the image forming operation is interrupted such as a failure of a device inside the image forming apparatus, for example, a failure of a fixing unit, a failure of a motor, or a failure of an operation panel. The error cannot be restored to the normal state unless the maintenance is performed by a service person or the like who specializes in the error. Also,
The third mode is an error that does not interrupt the image forming operation, and is an error that enables normal image formation by a user's operation or setting change (hereinafter, referred to as a “user error”). It is. This error occurs when there is an operation error of the host device by the user, a setting error of the application software running on the host device, or the like.

[0003] Among the errors that occur in such an image forming apparatus, regarding the errors of the second embodiment, the contents of the errors are sequentially stored in a storage means, and are operated by a predetermined operation such as a serviceman at the time of maintenance. A device for displaying the content of the error on a display device provided in the device in which the error has occurred is known (Japanese Patent Laid-Open No. 2-308151).
No. JP-A-2-184483). According to this conventional apparatus, a service person or the like can know the error history at the time of maintenance, so that it is possible to perform appropriate error recovery processing.

[0004]

However, with respect to the errors of the third embodiment, ie, user errors, conventionally, when an error occurs, the contents of the error are sequentially displayed on a display device on the image forming apparatus. I just did. Specifically, the user error is caused when the recording paper size or the paper feed tray is not properly selected, when the working area of the memory used for image formation is insufficient, or when the character code or the number of image forming copies is insufficient. This occurs when, for example, the characteristics of the image forming apparatus are not appropriate, and when such a case occurs, a “paper size selection error”, “ An error display such as "paper feed tray selection error", "memory area shortage error", "character code error", or "print copy number error" has been performed.

However, as described above, even if a user error occurs, the image forming operation is performed without interruption, and therefore, unless the user always monitors the display device of the image forming apparatus, Often, you do not notice the error. Particularly, in recent years, the image forming apparatus is often connected to a plurality of higher-level apparatuses via a network, and in such a case, the distance between the higher-level apparatus and the image forming apparatus increases. Therefore, the user who has created the image information on the host device cannot substantially monitor the display device on the image forming apparatus, and the possibility that a user error cannot be known is increased. . For this reason, as a result of the occurrence of a user error, for example, the image formation result is a result expected by the user, such as a case where an image to be formed on an A4 size recording paper is formed on a B5 size recording paper. If a situation different from the above occurs, what causes the expected image not to be obtained, if it is caused by a user error, what is the cause of the error, and how to deal with the error recovery? Getting information about user errors was troublesome.

SUMMARY OF THE INVENTION The present invention has been made in view of the above problems, and an object of the present invention is to confirm information on the user error on a host device when a user error occurs during image formation. An object of the present invention is to provide an image forming apparatus that can eliminate the trouble of a user going to an image forming apparatus to confirm information on a user error.

[0007]

According to a first aspect of the present invention, there is provided an image forming apparatus connected to a higher-level apparatus for transmitting image information and performing image formation based on the image information. In an apparatus, when an error that does not interrupt the image forming operation occurs, a storage unit that stores information related to the error as error information including code data, and stores the error information stored in the storage unit in the higher-level device. And a transmitting means for transmitting the data to the user.

In the image forming apparatus according to the present invention, when an error that does not interrupt the image forming operation occurs, information on the error is sequentially stored in the storage unit as error information including code data, and the stored error information is stored in the higher order. Send to device.

According to a second aspect of the present invention, in the image forming apparatus connected to a higher-level apparatus for transmitting image information and performing image formation based on the image information, an error that does not interrupt the image forming operation occurs. In this case, a storage unit that stores information on the error as error information composed of code data, a creating unit that creates message data composed of language data corresponding to the error information based on the stored error information, Transmitting means for transmitting message data to the host device.

In the image forming apparatus according to the present invention, when an error that does not interrupt the image forming operation occurs, information on the error is stored in the storage unit as error information including code data, and based on the stored error information, Message data composed of language data corresponding to the error information is created. Then, the message data is transmitted to the host device.

According to a third aspect of the present invention, in the image forming apparatus according to the first or second aspect, the error information includes an error countermeasure code indicating a countermeasure for eliminating the generated error. Is what you do.

In the image forming apparatus of the third aspect, the error information includes an error countermeasure code indicating a countermeasure for eliminating the generated error.

[0013] The image forming apparatus according to the fourth aspect is the first or second aspect.
Or, in the image forming apparatus of 3, the control unit for controlling the storage of the error information in the storage unit and the transmission by the transmission unit based on the control code sent from the higher-level device is provided. It is a feature.

In the image forming apparatus according to a fourth aspect, the control means controls the storage of the error information in the storage means and the transmission by the transmission means based on the control code sent from the host device.

[0015]

DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment in which the present invention is applied to a laser printer as an image forming apparatus will be described below. FIG. 1 is a laser printer according to the present embodiment (hereinafter referred to as a laser printer)
Simply called "printer". FIG.

The printer 1 according to the present embodiment is connected to a host device 4 which is a host device such as a computer or a word processor, and forms an image on a recording sheet based on image information sent from the host device 4. Is possible.
In order to perform such image formation, the printer 1 has the following configuration. That is, the printer 1 is broadly composed of a printer controller (hereinafter abbreviated as a controller) 2 which is a control means for controlling the entire printer, and a printer engine 3 (hereinafter referred to as an image forming means) which actually forms an image on a recording sheet. , An engine) and an operation panel 13 for giving instructions such as various mode settings from the user to the controller 2 and displaying various states of the printer 1.

The controller 2 includes a CPU (central processing unit) 10, a RAM 5, a font ROM 6, a program ROM 7, a nonvolatile RAM 8, an IC card 9, an engine interface 11, a panel interface 12,
It comprises a host interface 14 and these are connected by a system bus 15.

The CPU 10 is a control device, and based on a signal from the operation panel 13 or the host device 4,
By executing a predetermined program, various controls performed in the printer controller 2 are executed. The above CP
A program used for control by U10 is stored in a program ROM 7 which is a read-only memory. As described above, in addition to the program ROM 7, the controller 2 includes a font ROM as storage means.
6, a RAM 5, and a nonvolatile RAM 8. The font ROM 6 stores the program RO
Like the M7, the memory is a read-only memory, and stores pattern data of various fonts such as characters used for image formation. On the other hand, the RAM 5 and the nonvolatile RAM 8
Is a random access memory, which enables both writing and reading of data.

The RAM 5 is used as a working memory when the CPU 10 executes various controls. The RAM 5 is used as an input buffer for temporarily storing image information sent as code data from the host device 4. Further, the RAM 5 converts the image information into bitmap image data, and stores the image data. It is also used as a frame buffer for

The nonvolatile RAM 8 is a battery backup memory capable of retaining stored data even when the power is turned off. The nonvolatile RAM 8 stores the contents of mode instructions from the operation panel 13, environment setting data of the printer 1, and the like.

In order for the controller 2 to communicate with a device provided outside the controller 2, an interface is required. To this end, the controller 2 is provided with an engine interface 11, a panel interface 12, and a host interface 14.

The engine interface 11 is an interface for communicating commands, statuses, image data, and the like between the controller 2 and the engine 3. Panel interface 1 above
2 is between the controller 2 and the operation panel 15;
This is an interface for communicating commands and status. The disk interface 13
This is an interface for performing communication between the controller 2 and the disk device 16. The host interface 14 is an interface for the controller 2 to perform bidirectional communication with the host device 4. Due to having this host interface 14,
The controller 2 functions as transmitting means for transmitting information to the host device, and also functions as receiving means for receiving information from the host device 4.

In the printer 1 having the above configuration,
The general operation from the transmission of the image information from the host device 4 to the execution of the image forming operation based on the image information is as follows. Image information from the host device 4 is received via the host interface 14 and is temporarily stored in an input buffer formed on the RAM 5. The image information includes not only a character code but also a control code and the like.

When the storage of the image information in the input buffer is completed, a CPU interrupt is generated, and the CPU 10 is notified that the reception of the image information is completed. Upon receiving the notification, the CPU 10
The image information is taken out from the input buffer and analyzed according to an emulation program that matches the command system of the host device 4 stored in the input device. As a result of this analysis, the image information is converted into an intermediate code called a display list.

The intermediate code is stored in a page buffer formed on the RAM 5. Thus, when the storage of the intermediate code for one page is completed in the page buffer, C
The PU 10 executes the system program stored in the program ROM 7 and stores the intermediate code in the RAM 5
The image data is developed as bitmap image data in the frame buffer formed above. When the development is completed, the controller 2 sends a paper feed unit selection command and an image formation command to the engine 3 via the engine interface 11, and sends the image data developed in the frame buffer. Engine 3 receiving the above-mentioned paper feed unit selection command and image forming command
Executes the paper feed specified by the paper feed selection command, and forms an image based on the image data.

The image forming operation of the engine 3 will be described with reference to FIG. FIG. 2 is an explanatory diagram for explaining the operation of the engine 3. The image data from the controller 2 is input to the optical writing unit 22.
The optical writing unit 22 is provided with a laser diode (not shown) that blinks based on the image data and generates a light beam. The light beam from the laser diode is deflected by a polygon mirror 22a rotating at a high speed, and is deflected by an optical system 22 such as an fθ lens.
The light is uniformly charged by the charging device 27 via the mirror b and the mirror 22c, and is guided to the photoconductor 23 rotating clockwise in the drawing. Then, the light beam forms a latent image corresponding to the image data on the surface of the photoconductor 23. This latent image is
The toner image is visualized by the toner development by the developing device 24 and becomes a toner image.

On the other hand, while setting the timing of the formation of the latent image and the formation of the toner image, the first paper feed unit 2 specified by the paper feed selection command from the controller 2.
0, or the recording paper is fed from either the second paper feeding unit 21. The recording sheet is once again stopped by abutting the leading end of the recording sheet on the pair of registration rollers 26 in the conveying direction, and then reconveyed at a timing corresponding to the toner image on the surface of the photoconductor 23. A transfer device 25 is provided at a position downstream of the registration roller pair 26 in the transport direction and facing the photoconductor 23, and the transfer device 25
3 is transferred to the recording paper. The recording paper on which the transfer has been completed is transported by the transport belt 29 to a fixing device 30 including a heating roller and a pressure roller, and the toner image on the recording paper is fixed on the recording paper. The recording paper on which the fixing has been completed is transported by the transport roller pair 31 and is discharged onto a paper discharge tray 32. After the transfer by the transfer device 25 is completed, the surface of the photoconductor 23 is cleaned by the cleaning device 28 to collect the residual toner. Thus, the image formation for one page of the recording paper is completed.

Next, a process and the like when a user error occurs in the printer 1 according to the present embodiment will be described.
FIG. 3 is a diagram showing the contents of a user error information storage area for storing user error information, which is error information provided in the RAM 5. As shown in the figure, the user error information storage area includes a user error code for identifying a user error that has occurred, a user error cause code corresponding to each of the user error codes indicating the cause of the user error, and a user error code. A user error handling code indicating a countermeasure to resolve the user error
Additional information described later is stored as code data. Further, if necessary, the page number where the user error has occurred is also stored. The user error code, the user error cause code, the user error handling code and the accompanying information are sequentially stored in the user error information storage area every time a user error occurs. The same applies to the case where the page numbers are stored.

FIG. 11 shows an example of message data composed of language data corresponding to the user error code in FIG. The display contents are more detailed than the display contents of the conventional apparatus shown in FIG. 12, and the contents of the user error can be more easily understood. This is because, in the conventional apparatus, information about the user error is displayed on the display device on the image forming apparatus. Therefore, it is difficult to provide a very large display apparatus from the viewpoint of miniaturization and space saving of the image forming apparatus. For this reason, the display of the user error itself had to be simplified, but in the present embodiment, by transmitting information about the user error to the higher-level device, a display device or the like normally provided on the higher-level device is transmitted. It is in view of the fact that it becomes possible to use. FIG.
The message data as exemplified in 1 is stored in the ROM 7 in advance so as to correspond to each user error code. (Hereinafter, margin)

FIG. 4 is a diagram showing the correspondence between the user error cause codes and message data consisting of language data corresponding to the respective user error cause codes. The user error cause code is defined for each of the user error codes. For example, the user error cause code for the user error code “01” is defined as “C0100”, and the user error cause code for the user error code “02” is “C0
200 ". In addition, since there may be a plurality of causes of one user error, in the present embodiment, a user error cause code is defined for the user error code so that the plurality of causes can be determined. . In the illustrated example, the user error code “0”
For "3", the user error cause code "C030
Two user error cause codes of “0” and “C0301” are defined.

FIG. 5 is a diagram showing the correspondence between user error handling codes and message data consisting of language data corresponding to each user error handling code. Similarly to the user error cause codes described above, the user error handling codes are defined corresponding to each of the user error codes.

Here, the supplementary information in FIG.
And parameters z1, z2,... Appearing in FIG.
z13, etc., which is a portion in which a variable value or a variable character string (name) is entered. For example, z1 indicates the paper size name (A3, A4, B4,..., Etc), z2 indicates the number of the paper feed tray, and z4 and z5 indicate the values of the memory size. These parameters are set to corresponding numerical values and character strings at the time of occurrence of a user error. In addition, in the area of the additional information in FIG. 2, the values and names in FIGS. 4 and 5 are directly stored, or the additional information is stored separately from the user error information storage area.
It is prepared in the RAM 5 and stores the address value of the location where the supplementary information is stored.

The fixed part of the message data corresponding to the user error cause code or the user error handling code except for the parameter part (z1, z2,... Z13) corresponds to the user error code described above. It is stored in the ROM 7 like the message data. Then, the fixed part and the variable part are combined to create message data corresponding to the user error cause code or the user error handling code.

The above-described message data is transmitted to the host device 4 after the image formation in the printer 1 based on the image information from the host device 4 is completed. This will be described with reference to the flowchart of FIG. FIG. 6 is a flowchart illustrating the operation of the printer 1 when transmitting message data to the host device 4. First, when the image formation based on the image information from the host device 4 is completed, the CPU 10 checks whether or not a user error code exists in the user error information storage area of the RAM 5 (601). Creates on the RAM 5 message data corresponding to the stored user error code, user error cause code, and user error handling code on the RAM 5 for all the user error information (603, 604). The information message data is transmitted to the host device 4 via the host interface 14 (605). When the transmission of the message data for all the user error information to the host device 4 is completed, the user error information storage area of the RAM 5 is cleared (initialized) (606).

As is clear from the above, the controller 2, more specifically, the CPU 10 of the controller 2,
Based on error information composed of code data such as a user error code, it functions as a producing unit that produces message data composed of language data corresponding to each.

In the example of FIG. 6, in step 601,
Although the existence of the user error information is directly confirmed in the user error information storage area, this can be confirmed by the user error flag without directly confirming the user error information storage area. FIG. 7 shows a case where the presence or absence of user error information is confirmed based on the presence or absence of the user error flag. FIG. 7 is a flowchart illustrating an operation when a user error flag is used in transmitting message data. The user error flag is a software variable and is a RAM
5 is prepared. When a user error occurs and a user error code or the like is stored in the user error information storage area, a value for recognizing the fact of the storage is set, and a user error flag is set when the user area information storage area is cleared. Also clear. Conversely, this clear means a set of values that can recognize that no user error information exists.

In this embodiment, as described above, not only the user error information stored in the user error information storage area is converted into message data and transmitted to the host device 4, but also the user error information is not changed. It is also possible to transmit to the host device 4.

In this case, only the code data for specifying the user error is transmitted to the host device 4, and the amount of data to be transmitted from the printer 1 to the host device 4 is determined when the message data is transmitted. There is an advantage that the load required for the transmission of the printer 1 can be reduced by reducing the number of transmissions.

On the other hand, when the code data transmitted from the printer 1 is directly notified to the user by the display on the display device of the host device 4 or the voice by the voice output device, etc. It is necessary to specify what the above code data means. Therefore, in the present embodiment, when the user error information including the code data is directly transmitted to the host device 4, the host device 4 is provided with a function of converting the code data into the message data.

Generally, the CP used in the host device 4
U is much superior in performance such as processing speed to that used in the printer 1 in many cases, so that the printer 1 uses the CPU 10 in the printer controller 2 to create message data. Also, when the message data is created by the host device 4, the message data can be created at high speed.

In preparation for transmitting the user error information composed of code data from the printer 1 as described above, the message data as shown in FIGS. It is preferable to store the data in the RAM or ROM of the host device 4 in association with

FIG. 8 is a flowchart showing the operation of the printer 1 when the user error information including the code data described above is transmitted to the host device 4 as it is. First, the CPU 10 in the printer controller 2 checks whether or not a user error code exists in the user error information storage area (801). If the user error code exists, the CPU 10 stores the error information in the user error information storage area into the host device. 4 (803). When the transmission is completed, the user error information storage area is cleared (initialized) (804).

As in the case of transmitting the message data described above with reference to FIG. 7, when the user error information is transmitted to the host device, the user error flag is used without directly checking the contents of the user error information storage area. It is also possible to determine the presence / absence of user error information. The operation when the user error flag is used is shown in the flowchart of FIG.

First, the user flag is checked (9
01) If the user error flag is on, the user error information in the user error information storage area is transmitted to the host device 4 (902). When the transmission is completed, the user error information storage area is cleared (904), and the user error flag is cleared (904). Also in this case, the user flag is a software variable, as described above with reference to FIG.
This is set in the RAM 5.

In this embodiment, the control for storing the user error information described above in the user error information storage area of the RAM 5 and transmitting the user error information and the message data is performed by the host device 4.
Can be performed by a control code transmitted from the printer 1 to the printer 1. The operation of the printer 1 when the control code is sent from the host device 4 will be described with reference to the flowchart of FIG. FIG. 10 is a flowchart showing control relating to storage of user error information and transmission thereof.

First, upon receiving a control code from the host device 4, the controller 2 determines whether or not the control code is a code for controlling user error information (step 1001). If the control code is a control code for controlling the user error information, it is next determined whether or not the control code relates to storage of the user error information in the user error information storage area (step 1002). If the result of the determination is Yes, it is determined whether or not to store the user error information based on the control code (step 1006).
The user error information storage flag prepared in AM5 is turned on (step 1008), and when not stored, the user information storage flag is turned off (step 1007). Thereby, when a user error occurs thereafter, the CPU 10 in the controller 2 checks the flag, and if the flag is on, sequentially stores the user error information in the user error information storage area.

At step 1002, the judgment result is N
If it is o, it is determined whether or not the control code relates to the designation of the transmission format (step 1003). If the result of the determination is Yes, it is determined, based on the control code, whether the transmission format is "send message data consisting of language data" or "send as it is as user error information consisting of code data" ( Step 1009),
When transmitting in the format, the transmission format flag prepared in the RAM 5 is turned on (step 1010), and when transmitting in the format, the transmission format flag is turned off (step 1011). This transmission format flag is checked by the CPU 10 when a control code designating transmission of information on a user error to the host device 4 is transmitted from the host device 4 later.

In the above step 1003, the judgment result is No.
If it is, it is determined whether or not the control code is a control code designating transmission of information about a user error to the host device 4 (step 1004). If the determination result is Yes, first, the transmission format flag described above is checked to determine the transmission format (step 101).
2). Then, in the determined transmission format, that is, in any format of “message data consisting of language data” or “user error information consisting of code data”,
The controller 2 executes transmission to the host device 4 (Step 1013).

In step 1004, the determination result is No.
If it is, it is determined whether or not the control code is a control code for designating a user error information clearing process (step 1005). If the result of the determination is Yes, the user error information is cleared (step 101).
4). This clearing process includes a process of deleting the user error information from the user error information storage area, a process of clearing the user information storage area itself, and a process of clearing the area of the RAM 5 storing the user error flag. It also includes a process of clearing a working area of the RAM 5 used for creating message data for transmission. Thus, a series of control operations as described above are executed based on the control code from the host device 4.

[0050]

According to the image forming apparatus of the first aspect, the information on the error which does not interrupt the image forming operation is transmitted to the host device, so that the user can obtain the information on the generated error on the host device. This has an excellent effect that it is possible to eliminate the inconvenience of confirming by going to the image forming apparatus.

According to the image forming apparatus of the present invention, the message data composed of the language data is created on the basis of the error information and transmitted to the higher-level device. It has an excellent effect that it can be obtained on the apparatus and can eliminate the troublesome work of checking the image forming apparatus. Further, as compared with the image forming apparatus according to the first aspect, in which the error information including the code data is transmitted to the host apparatus, the present invention has an excellent effect that the user can easily confirm the error.

According to the image forming apparatus of the third aspect,
Since the error information includes an error countermeasure code indicating a countermeasure for resolving the generated error, the user knows on the host device how to cope with the generated error. It has an excellent effect that it becomes possible.

According to the image forming apparatus of the present invention, the storage of the error information in the storage means and the transmission of the error information by the transmission means are controlled based on the control code sent from the host apparatus. The user can perform the above-described control only by sending a control code from the higher-level device to the image forming apparatus, and has an excellent effect that the trouble of going to the image forming apparatus for such control can be eliminated.

[Brief description of the drawings]

FIG. 1 is a configuration block diagram of a laser printer according to an embodiment.

FIG. 2 is an explanatory diagram for explaining the operation of the printer engine.

FIG. 3 is a diagram showing the contents of an error information storage area.

FIG. 4 is a diagram showing a correspondence relationship between user error cause codes and message data composed of language data corresponding to each user error cause code.

FIG. 5 is a diagram showing the correspondence between user error handling codes and message data composed of language data corresponding to each user error handling code.

FIG. 6 is a flowchart for explaining the operation of the printer 1 when transmitting message data to the host device 4;

FIG. 7 is a flowchart illustrating an operation when a user error flag is used in transmitting message data.

FIG. 8 is a flowchart showing an operation of the printer 1 when transmitting user error information including code data to the host device 4.

FIG. 9 is a flowchart illustrating an operation when a user error flag is used in transmitting user error information including code data.

FIG. 10 is a flowchart showing control related to storage of user error information, transmission of user error information, and the like.

FIG. 11 is a diagram showing an example of message data composed of language data corresponding to a user error code.

FIG. 12 is a view showing a user error display in the conventional device.

[Description of Signs] 1 Laser printer 2 Printer controller 3 Printer engine 4 Host device 5 RAM 6 Font ROM 7 Program ROM 8 Non-volatile RAM 9 IC card 10 CPU 11 Engine interface 12 Panel interface 13 Operation panel 14 Host interface 20 First supply Paper unit 21 Second paper feed unit 22 Optical writing unit 23 Photoconductor 24 Developing device 25 Transfer device 26 Registration roller pair 27 Charging device 28 Cleaning device 29 Transport belt 30 Fixing device 31 Transport roller pair

Claims (4)

[Claims] 1. An apparatus for transmitting image information, comprising:
In an image forming apparatus that performs image formation based on the image information, when an error that does not interrupt the image forming operation occurs, a storage unit that stores information about the error as error information including code data; A transmitting unit for transmitting the error information stored in the unit to the higher-level device. 2. An apparatus connected to a higher-level device for transmitting image information,
In an image forming apparatus that performs image formation based on the image information, when an error that does not interrupt the image forming operation occurs, a storage unit that stores information about the error as error information including code data; An image providing means for creating message data composed of language data corresponding to the error information based on the error information, and a transmitting means for transmitting the message data to the host device. Forming equipment. 3. The image forming apparatus according to claim 1, wherein the error information includes an error countermeasure code indicating a countermeasure for eliminating the generated error. 4. The image forming apparatus according to claim 1, 2 or 3, wherein said error information is stored in said storage means and transmitted by said transmission means based on a control code sent from said higher-level device. An image forming apparatus comprising a control unit for controlling the image forming apparatus.