JPH11184760A - Picture forming device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To efficiently and surely update the program of a necessary circuit board without necessitating any work such as ROM exchange. SOLUTION: This picture forming device is provided with plural circuit boards for each function, and a flash memory for each circuit board. This flash memory calculates a check sum from a check code included in data (S2), collates the calculated check sum with a check sum for collation for judging whether the data are normal or abnormal (S3), receives data for rewriting from the outside part (S5), and executes the rewriting of the data (S7 and S8) when it is judged that the data are abnormal.

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, and more particularly, to rewriting of a flash memory by updating a circuit board application program, adding a circuit board with the addition of a function, or a program in a flash memory. The present invention relates to an image forming apparatus in which rewriting due to abnormal data is considered.

[0002]

2. Description of the Related Art In an image forming apparatus such as a copying machine or a printer, a plurality of circuit boards are provided for each block and functions such as a main board, a mechanical control board, a printer option board, and a FAX option board.

[0005] Each of the plurality of circuit boards has a memory in which a program for controlling the operation of each circuit board is stored. Conventionally, a memory chip such as a PROM is used as this memory. When a program needs to be changed, the chip is removed from each circuit board, rewritten by an external device, and then inserted into each circuit board. I was

[0004]

Problems to be solved by the present invention are as follows: update of an application program of a circuit board; rewriting of memory by adding a circuit board due to addition of a function; and rewriting of an abnormal program data in the memory. This must be done in cases such as rewriting.

[0005] However, in the above-mentioned method of exchanging chips, the operation is complicated. It is also difficult for a user to do. There is a flash memory as a memory that can cope with such a problem, and it is technically possible to rewrite from the outside. However, when a plurality of circuit boards having different functions each having a flash memory are provided in one apparatus, there has been no method that considers how to use the flash memory.

SUMMARY OF THE INVENTION The present invention has been made in view of such a problem, and an image forming apparatus capable of efficiently and surely updating a program of a necessary circuit board without requiring work such as ROM replacement. The purpose is to provide.

[0007]

That is, the present invention for solving the above-mentioned problems is as follows. (1) The invention according to claim 1 is an image forming apparatus including a plurality of circuit boards for each function and a flash memory for each circuit board, wherein the flash memory is checked from a check code included in data. Calculation means for calculating a sum, checksum holding means for holding a checksum for verification in advance, and determination means for comparing the calculated checksum with the checksum for verification to determine whether the data is normal or abnormal. An image forming apparatus comprising:

According to the present invention, the flash memory calculates a checksum from the check code included in the data and compares the calculated checksum with the checksum for comparison to determine whether the data is normal or abnormal. It is desirable to check such data at the time of turning on the power.

As a result, normal / abnormal data can be determined for each circuit board. Also, because it is a flash memory,
It is possible to update the necessary circuit board program without the need for a work such as ROM exchange. Also, it is possible to check whether the updated program is normal or not.

(2) In the image forming apparatus of (1), the application program is not executed when the data is judged to be abnormal by the judgment means.

As a result, the normality / abnormality of data can be determined for each circuit board, and when an abnormality is detected, execution of an abnormal application program can be prevented. (3) In the image forming apparatus of (1), when the data is judged to be abnormal by the judging means, the image forming apparatus waits in a data rewriting waiting state of the flash memory. .

As a result, the normality / abnormality of data can be determined for each circuit board, and when an abnormality is detected, execution of an abnormal application program can be prevented. According to a fourth aspect of the present invention, in the image forming apparatus of the first aspect, the flash memory comprises a data rewriting means, and when the judging means judges that the data is abnormal, the rewriting data is externally supplied. It is characterized by receiving and rewriting data.

According to the present invention, the flash memory calculates the checksum from the check code included in the data and compares it with the checksum for comparison, thereby determining whether the data is normal or not. Receives rewriting data from the outside and executes data rewriting.

As a result, it is possible to realize an image forming apparatus that can efficiently and surely update a necessary program on a circuit board without requiring an operation such as ROM replacement. (5) The invention according to claim 5 is an image forming apparatus comprising a plurality of circuit boards for each function and a flash memory for each circuit board, wherein the boot means of the flash memory comprises a plurality of different types of boots. An image forming apparatus comprising: a plurality of boot programs corresponding to respective flash memories; and a function of identifying and executing a program corresponding to the flash memory from the plurality of boot programs. is there.

According to the present invention, the flash memory boot means includes a plurality of boot programs corresponding to a plurality of different types of flash memories, respectively, and a boot program corresponding to the flash memory is selected from the plurality of boot programs. Identify and execute.

Therefore, a common boot program can be used, and it is easy to use different types of flash memories. (6) In the image forming apparatus of (3), the boot program is a program for rewriting a data area of a flash memory.

According to the present invention, the flash memory boot means includes a plurality of boot programs respectively corresponding to a plurality of different types of flash memories, and a boot program corresponding to the flash memory is selected from the plurality of boot programs. Is identified, and the data area of the flash memory is rewritten.

Therefore, a common boot program can be used, and it is easy to use different types of flash memories. Further, it is possible to realize an image forming apparatus capable of efficiently and surely updating a program of a necessary circuit board without requiring an operation such as ROM replacement.

[0019]

Embodiments of the present invention will be described below in detail with reference to the drawings. An image forming apparatus according to the present invention includes a copying machine that reads a document, forms an image, and outputs the image.
The present invention can be used for a printer or the like which receives image data from a computer device and forms and outputs an image. In this embodiment, a case where the present invention is applied to a copying machine will be described as an example.

FIG. 1 is a block diagram showing an example of an electrical configuration in which an image forming apparatus according to an embodiment of the present invention is applied to a copying machine, and FIG. 2 is a block diagram showing an overall state of FIG. 1 and 2, reference numeral 100 denotes an image forming apparatus;
A main board 110 for controlling the entire image forming apparatus, and a mechanical control board 12 for controlling mechanical components of the image forming apparatus
0, a printer option board 130 for controlling a portion related to printing, an FA for controlling a facsimile transmission and reception
An example provided with a plurality of circuit boards (hereinafter simply referred to as boards) such as an X option board 140 is shown as an example.

Here, each substrate includes CPUs 111, 121, 131, and 141 for controlling the operation of each substrate, and memories (RAMs) 112 and 12 as data working areas.
2, 132, 142, and a flash ROM (hereinafter referred to as a flash memory) 113, 123, 133, 1 for holding an application program for each board.
43, and the like.

A communication section 114 is provided on the main board 110.
And is configured to be able to receive data from an external device via a connection I / F (parallel I / F, serial I / F, and other various buses).

The main board 110 has dual port memories 115, 116 and 117,
Through this dual port memory, the mechanical control board 12
0, the printer option board 130, and the FAX option board 140 to exchange data.
Note that there may be substrates other than those shown here,
They are also included in the present invention.

Reference numeral 200 denotes an external device such as a computer, which supplies rewrite data and the like to the image forming apparatus 100 in this embodiment. In this image forming apparatus, a document is read by a scanner unit, the read image data is written as a latent image on a photosensitive drum by laser light, the latent image is converted into a toner image by a developing unit, and the toner image is recorded on recording paper. The image is transferred, fixed, and discharged outside the machine. The main board 110 handles such electrical processing of the image forming apparatus, and the mechanical control board 120 handles mechanical operations. The printer option board 130 and the FAX option board 140 are configured to handle operations based on various options.

The above flash memories 113, 1
23, 133, and 143 may use different manufacturers and different types of flash memories for each substrate. For example, as shown in FIG. 3A, the internal data structure of the product a manufactured by Company A is as follows: a boot block of 16 kilobytes, a parameter block of 8 kilobytes, a parameter block of 8 kilobytes, a main block of 96 kilobytes, and three blocks. , A main block of 128 kilobytes.

As shown in FIG. 3 (b), the product b manufactured by Company B comprises a boot block of 16 kilobytes, a parameter sector of 32 kilobytes, a parameter sector of 8 kilobytes, and seven main sectors of 64 kilobytes. Have been.

As described above, the internal data structure differs depending on the product. Further, the writing algorithm and the erasing algorithm are different depending on the manufacturer.
Therefore, at the time of rewriting, a program that matches the product is required.

In this embodiment, a flash memory rewrite determination program is stored in a 16-kilobyte boot block in any flash memory. Further, as will be described later, even if flash memories of different manufacturers and different types are used, a common program is used to cope with the flash memory. Therefore, a plurality of programs corresponding to each flash memory are included, and a product identification ID is included. According to the above, a suitable program is started up.

An 8-kilobyte parameter block and parameter sector are used as an area for storing a checksum described later. An application program is stored in the remaining main blocks and main sectors. This area is used as a checksum calculation target area as described later.

Here, the processing procedure of this embodiment will be described with reference to FIGS. FIG. 4 shown here is a flowchart of a startup processing procedure when the power is turned on, and is a flash memory rewrite determination program.

When the power is turned on, the flash memories 113, 123, 133, and 143 of the respective boards start up the boot programs stored in the respective boot blocks. The application program does not start until the processing of the boot program is completed.

First, the boot program identifies a flash memory product (S1 in FIG. 4). That is, it recognizes a manufacturing company and a product identification ID (a manufacturer ID, a device ID, etc.) indicating a product name (model number) stored in a predetermined area of the flash memory (S1 in FIG. 5). As a result, a rewrite determination program corresponding to the flash memory is identified and executed from among a plurality of boot programs corresponding to a plurality of different types of flash memories (S2 in FIG. 5).

A case where a plurality of boot programs are stored in a boot block and selected and executed,
It is conceivable that a single boot program branches to a subroutine that matches the product and executes processing.
Either method may be used.

In this way, even if different products have different data structures and erasing algorithms, the entire boot program can be shared. Therefore, since the boot program can be made common, it is easy to use different types of flash memories.

In the following, the processing will be specifically performed for each product using a different algorithm or the like, but basically the same processing procedure will be described. Next, the boot program calculates a checksum for the application program stored in the main block or main sector (see FIG. 3) (S2 in FIG. 4).

The checksum calculated at this time is compared with the checksum for verification stored in the parameter sector when writing the application program, and it is checked whether or not they match (S3 in FIG. 4).

If the checksums match, there is no abnormality, so the flash memory rewrite determination program shown here is terminated and the application is started (S4 in FIG. 4).

If any part of the checksums does not match, it means that an abnormality has occurred, so that the apparatus enters the rewrite mode and waits for reception of rewrite data (S5 in FIG. 4). .

At this stage, the flash memory rewriting determination program notifies the operator of the rewriting mode and waiting for the rewriting data by displaying on the display unit of the image forming apparatus. The display may be a simple one such as lighting of an LED.

Thus, the operator connects an external device such as a computer to the image forming apparatus via the connection I / F (parallel I / F, serial I / F, and other various buses), and converts the rewriting data into the image. Transmit to device.

The data format of the rewriting data in this case is as shown in FIG. That is, communication start instruction data indicating the start of communication, a model name code indicating the model name of the image forming apparatus, a board name code indicating the board name, rewriting data of a predetermined length unit of the application program,
Check sum for collation to be stored. In addition, data indicating the date, month, day, hour, minute, and second, ROM version data, and the like may be included as link information.

There are various types of checksums. For example, the sum from the first data to the last data may be added, and a value obtained by adding one's complement of the added value may be used.

When the abnormality is detected as described above, the rewriting data transmitted from the external device 200 is not limited to the data of the specific board concerned, but the data of a plurality of boards is transmitted collectively. You may. Because
This is because only the board in which an error is detected in the checksum is in a reception waiting state, and only the corresponding data can be selected on the board side. When the selection is made on the board side as described above, the selection is made by referring to the model name code and the board name code included in the header of the rewrite data.

The rewriting data is stored in a RAM on a substrate having a flash memory in a reception waiting state.
Is temporarily stored, and it is checked whether or not the reception was successful (S6 in FIG. 4).

If the reception is not performed normally, an error process is started. As an error process in this case, the operator is notified again by the display on the display unit of the image forming apparatus that the rewriting mode is set and the reception of the rewriting data is waiting (S9 in FIG. 4).

When the rewrite data is received normally, all blocks other than the boot block are erased according to the algorithm of each flash memory (S7 in FIG. 4). After the erasure is completed, the received checksum and rewriting data are written to the parameter block or parameter sector or the main block or main sector of the flash memory according to the algorithm of each flash memory (S8 in FIG. 4).

The above-described checksum for verification is written in the parameter block or the parameter sector, and the application program is written in the main block or the main sector based on the rewriting data.

When the rewriting is completed as described above, the flash memory rewriting determination program is terminated, and the application program written in the flash memory is started (S4 in FIG. 4).

The received rewriting data is stored in a RAM.
Instead of writing the data once to the flash memory and writing it to the flash memory, the data may be written to the flash memory for each received fixed-length rewrite data.

That is, as shown in FIG. 7, a comparison between the calculated checksum and the checksum for comparison (FIG. 7S
When 3) is detected, the rewrite mode is entered, and a state of waiting for reception of rewrite data is entered (S5 in FIG. 7).

At this point, when the reception is started, all blocks other than the boot block are erased according to the algorithm of each flash memory (S6 in FIG. 7). Then, the received checksum and rewriting data are sequentially written to the parameter block or parameter sector or the main block or main sector of the flash memory according to the algorithm of each flash memory (S7 in FIG. 7).

When reception and writing are completed, a checksum is calculated for the application program stored in the main block or main sector (S8 in FIG. 7), and the calculated checksum is compared with the checksum for comparison. To determine whether they match (S9 in FIG. 7).

At this point, if the checksums match, the newly written data has no abnormality, and thus the flash memory rewrite determination program shown here is terminated and the application is started (FIG. 4S).
4). If a mismatch is detected, error processing starts,
The operator is again notified that the mode is the rewriting mode and the reception of the rewriting data is waiting (S10 in FIG. 7).

As described above, the checksum is added to the rewriting data of the present embodiment, and by using the comparison judgment based on the checksum at the time of rewriting, the received rewriting data can be sequentially written while being received. Also becomes possible.

The processes shown in the flowcharts of FIGS. 4 and 7 are executed in parallel for each substrate. In the above embodiment, the checksum is used.
Instead, another error detection code may be used.

As described above in detail, according to each embodiment of the present invention, it is possible to efficiently and surely update a necessary program on a circuit board without requiring a work such as ROM replacement. Become.

[0057]

As described above, according to the present invention, the following effects can be obtained.

(1) According to the first aspect of the present invention, the flash memory calculates a checksum from the check code included in the data, and compares the checksum with the checksum for comparison to determine whether the data is normal or abnormal. As a result, whether the data is normal or abnormal can be determined for each circuit board, and since the flash memory is used, it is possible to update the necessary circuit board program without the need for an operation such as ROM replacement. Also, it is possible to check whether the updated program is normal or not.

(2) According to the fourth aspect of the present invention, the application program is not executed when the data is determined to be abnormal, so that the normality / abnormality of the data can be determined for each circuit board. Execution of a simple application program can be prevented.

(3) In the invention according to claim 4, when it is determined that the data is abnormal, the flash memory waits in a data rewriting waiting state, so that the normality / abnormality of the data can be determined for each circuit board. When an error is detected, execution of an abnormal application program can be prevented.

(4) According to the invention described in claim 4, the flash memory calculates the checksum from the check code included in the data and compares it with the checksum for comparison to determine whether the data is normal. When there is an abnormality, the rewriting data is received from the outside and the data is rewritten.

As a result, it is possible to realize an image forming apparatus that can efficiently and surely update a necessary program on a circuit board without requiring an operation such as ROM replacement. (5) In the invention described in claim 5, the boot means of the flash memory includes a plurality of boot programs corresponding to a plurality of different types of flash memories, respectively.
From among a plurality of boot programs, a program corresponding to the flash memory is identified and executed, so that a common boot program can be used,
It is easier to use different types of flash memories.

(6) In the invention described in claim 6, the flash memory boot means includes a plurality of boot programs corresponding to a plurality of different types of flash memories, respectively. Since the flash memory corresponding to the flash memory is identified and the data area of the flash memory is rewritten, a common boot program can be used, and different types of flash memories can be easily used. become. Therefore, it is possible to realize an image forming apparatus that can efficiently and surely update a program of a necessary circuit board without requiring an operation such as ROM replacement.

[Brief description of the drawings]

FIG. 1 is a block diagram illustrating an example of an electrical configuration in which an image forming apparatus according to an embodiment of the present invention is applied to a copying machine.

FIG. 2 is a block diagram illustrating an overall configuration of an image forming apparatus according to an embodiment of the present invention.

FIG. 3 is an explanatory diagram illustrating an example of an internal data structure of a flash memory used in the image forming apparatus according to the embodiment of the present invention;

FIG. 4 is a flowchart illustrating a processing procedure according to the embodiment of the present invention.

FIG. 5 is a flowchart illustrating details of a main part of a processing procedure according to the embodiment of the present invention.

FIG. 6 is an explanatory diagram showing an example of a data format of rewriting data according to the embodiment of the present invention.

FIG. 7 is a flowchart illustrating another example of the processing procedure according to the embodiment of the present invention.

[Explanation of symbols]

 Reference Signs List 100 Image forming apparatus 110 Main board 111, 121, 131, 141 CPU 112, 122, 132, 142 RAM 113, 123, 133, 143 Flash memory 114 Communication unit 115, 116, 117 Dual port memory 120 Mechanical control board 130 Printer option Substrate 140 Fax option substrate 200 External device

Claims (6)

[Claims] 1. An image forming apparatus comprising a plurality of circuit boards for each function and a flash memory for each circuit board, wherein the flash memory calculates a checksum from a check code included in data. And checksum holding means for holding a checksum for comparison in advance, and determining means for comparing the calculated checksum with the checksum for verification to determine whether the data is normal or abnormal. Image forming apparatus. 2. The image forming apparatus according to claim 1, wherein the application program is not executed when the data is determined to be abnormal by the determination unit. 3. The image forming apparatus according to claim 1, wherein when the determination unit determines that the data is abnormal, the flash memory waits in a data rewriting wait state. 4. The flash memory according to claim 1, further comprising a data rewriting means, wherein when the judging means judges that the data is abnormal, the flash memory receives rewriting data from outside and rewrites the data. Item 2. The image forming apparatus according to Item 1. 5. An image forming apparatus comprising a plurality of circuit boards for each function and a flash memory for each circuit board, wherein the boot means of the flash memory corresponds to each of a plurality of different types of flash memories. An image forming apparatus comprising: a plurality of boot programs; and a function of identifying and executing a program corresponding to the flash memory from the plurality of boot programs. 6. The image forming apparatus according to claim 5, wherein said boot program is a program for rewriting a data area of a flash memory.