JP2002351738A - Image forming apparatus and information updating method in the apparatus - Google Patents

Abstract

(57) Abstract: Provided is an image forming apparatus capable of updating count data to a storage element such as a semiconductor memory in a short time, and an information updating method in the apparatus. SOLUTION: Count data is composed of a 2-byte gray code. The count data is divided into two pieces of data, an upper byte and a lower byte, and two 1-byte (8-bit) storage areas are provided in a serial EEPROM (storage element). Then, when writing the count data in the RAM 13 to the EEPROM of the unit as necessary, only the changed divided data changed according to the change of the count data is serially transferred to the EEPROM, and the count data in the EEPROM is rewritten. For this reason, the count data is EE compared to the conventional device that serially transfers all the count values.
Data can be stored in a storage element such as a PROM in a short time.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] 1. Field of the Invention [0002] The present invention relates to an image forming apparatus such as a printer, a copying machine, and a facsimile apparatus, and a method of updating information in the apparatus.

[0002]

2. Description of the Related Art An image forming apparatus of this type uses an accumulated value such as the number of rotations of a photosensitive member or an intermediate transfer medium, and the like.
It manages the usage state of the photoreceptor or a unit that is replaceably provided to the apparatus main body, that is, the life of the unit. For example, when the rotation accumulated value of the photoconductor reaches the usage limit value, a notification of the life of the image forming apparatus or a notification of replacement of the photoconductor is issued. Here, a mechanical counter or an electronic counter such as a semiconductor memory has conventionally been used in order to obtain the accumulated rotation value of the photoconductor, but since the mechanical counter is highly reliable but expensive, Recently, cheaper electronic counters have been frequently used. This electronic counter includes a storage element such as a nonvolatile semiconductor memory, and counts up count data stored in the storage element based on a signal generated in the apparatus in accordance with an operation of a photoconductor or an intermediate transfer medium. Is counting down.

When updating the count data, it is necessary to transfer the updated data to the storage element as necessary and write the data. For example, as described in Japanese Patent Application Laid-Open No. 2000-172133, The entire data is transferred to the storage element by serial transfer, and written to the storage element.

[0004]

By the way, since such a process of updating the count data requires a predetermined storage control and power supply, it is desired that the count data be updated and stored in a short time. I have. This is because if a power failure occurs during the update process and the voltage drops below the operation guarantee voltage during data transfer, correct count data cannot be stored, and erroneous data will not be stored. This is because if the time can be shortened, such a problem can be solved.

The present invention has been made in view of the above problems, and provides an image forming apparatus capable of updating count data in a storage element such as a semiconductor memory in a short time, and an information updating method in the apparatus. The purpose is to do.

[0006]

According to the present invention, there is provided a storage element for electrically storing count data, the count data being changed based on a signal generated in the device, and serial transfer of the count data. Control means for writing to the storage element by the control means, in order to achieve the above object, the control means divides the count data into a plurality of count data, Only the variable divided data including the bit changed accordingly is serially transferred to the storage element and written to the storage element. It is composed of a code such that one or more divided data does not change (claim 1).

In the invention configured as above, the count data is composed of a plurality of divided data, and when the count data changes according to a signal, at least one of the plurality of divided data does not change. Consists of code. As a result, when the count data changes based on the signal, the variable divided data that changes before and after the change becomes a part of the plurality of divided data. Therefore, in the present invention, only the changed divided data is serially transferred to the storage means and written into the storage means.
In this way, by serially transferring only the variable division data that changes according to the signal, the storage content of the storage unit can be rewritten, and the time required for storing the count data in the storage element can be reduced.

Here, the storage element may be configured to have the same number of storage areas as the number of divisions of the count data.
In this case, each time the count data is updated in response to the signal, the variable division data may be written to the storage area corresponding to the variable division data. Also,
The storage element may be configured to have a storage area of n times (n is an integer of 2 or more) the number of divisions of the count data. In this case, n storage areas are associated with each division data. In advance, each time the count data is updated in response to the signal, the variable division data may be sequentially written into the n storage areas corresponding to the variable division data.

A serial E is an example of a storage element.
A nonvolatile memory such as an EPROM or a serial FRAM can be used (claim 4).

Incidentally, some image forming apparatuses are provided with at least one or more replacement units.
In such an image forming apparatus, if a storage element is provided in each exchange unit, count data corresponding to each exchange unit can be stored (claim 5).
Here, as the count data, for example, information indicating the use state of the replacement unit can be adopted (claim 6), whereby the unit life, consumption of consumables, etc. can be obtained for each replacement unit. it can.

As the count data, a gray code (claim 7) or a ring code (claim 9) can be employed. In particular, when a gray code is employed as the count data, the storage element has m bytes (m ≧
In the case of the non-volatile memory of 2), the number of divisions of the count data is set to m, and only the variable division data including the bit changed according to the signal out of the division data is serially transferred to the storage element and is stored in the storage element. What is necessary is just to write (claim 8).

Further, the present invention is an information updating method for changing count data based on a signal generated in an image forming apparatus and writing the count data to a storage element by serial transfer. In order to achieve the above, the count data is divided into a plurality of pieces, and when the count data changes according to the signal, at least one of the plurality of pieces of the split data is constituted by a code that does not change. Of the divided data, only the variable divided data including the bit changed according to the signal is serially transferred to the storage element and written into the storage element (Claim 10).

In the information updating method configured as described above, the count data is composed of a plurality of divided data, and when changing according to a signal, at least one of the plurality of divided data changes. It does not consist of such code. Therefore, when the count data changes based on the signal, the change division data that changes before and after the change becomes a part of the plurality of division data. Therefore, in this information updating method, instead of serially transferring all of the divided data, only the changed variable divided data of the divided data is serially transferred to the storage means and written into the storage means, so that each count data is updated. The rewriting process for the storage element due to the change is simplified, and the time required to store the count data in the storage element is reduced.

[0014]

FIG. 1 is a diagram showing one embodiment of an image forming apparatus according to the present invention. FIG. 2 is a block diagram showing an engine controller of the image forming apparatus of FIG. This image forming apparatus forms a full-color image by superimposing four color toners of yellow (Y), magenta (M), cyan (C), and black (K), or uses only black (K) toner. To form a monochrome image. In this image forming apparatus, when an image signal is given from an external device such as a host computer to a main controller of a control unit, an engine controller 1 controls each part of an engine unit EG in response to a command from the main controller to copy paper. , Transfer paper, paper and OH
An image corresponding to an image signal is formed on a sheet S such as a P transparent sheet.

In the engine section EG, there are seven units: (a) the photosensitive unit 2; (b) the yellow developing unit 3Y; (c) the magenta developing unit 3M; (d) the cyan developing unit 3C; ) Black developing unit 3K; (f)
The intermediate transfer unit 4 and the (g) fixing unit 5 are detachable from the apparatus main body 6. In a state where all the units 2, 3Y, 3M, 3C, 3K, 4, and 5 are mounted on the apparatus main body 6, as shown in FIG. D1 and the charging unit 22 and the developing units 3Y, 3M, 3C, around the photosensitive member 21 along the rotation direction D1.
The 3K rotary developing unit 3 and the cleaning unit 23 are arranged.

7 units 2, 3Y, 3M, 3C, 3
Among the photoconductor units 2 of K, 4, and 5, a photoconductor 21, a charging unit 22, and a cleaning unit 23 are accommodated in the photoconductor unit 2.
These are integrally detachable from the apparatus main body 6. The charging unit 22 is charged with a charging bias, and charges the outer peripheral surface of the photoconductor 21 uniformly.

The photoconductor unit 2 is provided with a cleaning unit 23 upstream of the charging unit 22 in the rotation direction D1 of the photoconductor 21. The cleaning unit 23 remains on the outer peripheral surface of the photoconductor 21 after the primary transfer. Scrape off the toner.
Thus, the surface cleaning of the photoconductor 21 is performed.

A serial EEPROM 71 for storing data indicating the remaining life of the unit 2 is attached to the photoconductor unit 2 configured as described above. Is electrically connected to the engine controller 1 of the apparatus main body 6 through a connector (not shown).
The data transfer is performed between the printer 1 and the printer 1 to manage the life of the photoconductor unit 2 and the management of consumables. The other units 3Y,
Photoconductor unit 2 for 3M, 3C, 3K, 4 and 5
EEP for storing various data as well as
ROMs 72 to 77 are respectively mounted, electrically connected to the engine controller 1 of the apparatus main body 6 when the unit is mounted, performing data transfer with the engine controller 1, and managing the life of the unit and the management of consumables. Do.

In this image forming apparatus, as shown in FIG. 1, a laser beam L is emitted from the exposure unit 8 to the outer peripheral surface of the photosensitive member 21 charged by the charging section 22. The exposure unit 8 scans and exposes the laser beam L onto the photoconductor 21 according to an image signal from the engine controller 1 to form an electrostatic latent image on the photoconductor 21 corresponding to the image signal.

The electrostatic latent image thus formed is developed by the developing unit 3 with toner. That is, in this embodiment, as the developing unit 3, the developing unit 3K for black, the developing unit 3C for cyan, and the developing unit 3 for magenta are used.
A developing unit 3Y for M and yellow is provided rotatably about the axis. The developing units 3K, 3C, 3M, and 3Y are rotationally positioned and selectively positioned at the contact or separated positions with respect to the photoconductor 21, and a DC component or a DC component with an AC component superimposed thereon is developed. A bias is applied to apply the selected color toner to the surface of the photoconductor 21. Thus, the electrostatic latent image on the photoconductor 21 is visualized with the selected toner color.

The toner image developed by the developing unit 3 as described above is primarily transferred onto the intermediate transfer belt 41 of the intermediate transfer unit 4 in the primary transfer area TR1. That is, the intermediate transfer unit 4 includes an intermediate transfer belt 41 stretched over a plurality of rollers, and a driving unit (not shown) that drives the intermediate transfer belt 41 to rotate. In order to form a color image by superimposing toner images of respective colors formed on the photosensitive member 21 on the intermediate transfer belt 41, when a monochrome image is to be transferred to the sheet S, the toner image is formed on the photosensitive member 21. Only the black toner image to be transferred is transferred onto the intermediate transfer belt 41 to form a monochrome image.

In this embodiment, as will be described later, the remaining life of each unit is obtained. Therefore, as a scale for estimating the remaining life, the rotational speed of the intermediate transfer belt 41 during the operation of the unit is used. Use accumulation. To this end, a hole (index hole) is provided outside the margin of the intermediate transfer belt 41, and a transmission type photosensor including a light emitter and a light receiver is provided in the intermediate transfer unit 4 so as to face a position where the hole passes. And the intermediate transfer belt 41
The photosensor outputs a pulse signal (corresponding to the “signal” of the present invention in this embodiment) every time the hole rotates and the hole passes through the photosensor.

The image formed on the intermediate transfer belt 41 is secondarily transferred onto the sheet S taken out of the cassette 9 in a predetermined secondary transfer area TR2. The sheet S on which the image is formed is conveyed to the discharge tray provided on the upper surface of the apparatus body 6 via the fixing unit 5.

Next, the configuration of the engine controller 1 will be described with reference to FIG. This engine controller 1 functions as control means of the present invention,
The CPU 11 executes a count data update process (information update program), which will be described later, and stores the count data in a short time in a storage element such as a serial EEPROM mounted on each unit due to a power failure such as a power failure.
The CPU 11 is connected to a ROM 12 for storing an information update program and other data, and a RAM 13 for temporarily storing various data.

The CPU 11 is connected via a serial I / F (interface) 15 to a serial EEPROM 14 used for an electronic counter. The serial EEPROM 14 stores count data indicating the remaining life of each unit, the cumulative number of pages printed, the dot count value for each toner color, and the like.

The CPU 11 has a serial EEPROM.
Not only M14 but also each unit 2, 3Y, 3M, 3C,
Serial EEPROMs 71 to 71 provided in 3K, 4 and 5
77 is also connected via a serial I / F 15
Data can be transferred between the serial EEPROMs 14, 71 to 77, and a chip select signal CS can be input to the serial EEPROMs 14, 71 to 77 via the input / output port 16.

Further, the engine controller 1 is provided with a voltage monitoring circuit 17, and when the power supply voltage falls below a predetermined voltage due to a power failure or the like, the voltage monitoring circuit 17 detects the voltage drop, and resets to that effect. Signal to CPU1
1 and output to peripheral devices 15 and 16.

In the first embodiment configured as described above,
When each unit is new, the count data is changed to "1".
5 ", the count data is decremented by one each time the unit is used by a predetermined amount, and when the count data becomes" 0 ", it is determined that the unit has reached the end of its life. are doing. Also, serial EE
The PROM (storage element) has a storage area of 1-bit configuration of 16
If necessary, a total of 8 bits of command 3 bits + address 4 bits + data 1 bit can be serially transferred as one communication unit. For example,
Set the write command to “010” and set the serial EEPROM
When writing data “0” to the address 3 of M, “01000” is written from the engine controller 1 to the serial EEPROM side.
110 "is transferred.

Therefore, in this embodiment, the count data is stored in the serial EEPROM attached to the corresponding unit.
In order to reduce the time required for updating the count data stored in the ROM (storage element), the count data is constituted by a 16-bit ring code shown in FIG. Hereinafter, the serial EEPROM in this embodiment will be described.
The procedure for updating the count data in the OM (storage element) will be described, and its operation and effect will be described in comparison with a case where the count data is configured by a binary code as shown in FIG. 4 (comparative example).

In the image forming apparatus according to the first embodiment, the same data as the count data stored in each unit in advance is stored in the RAM 13, and each data in the RAM 13 is stored in accordance with the execution of the image forming process. Decrease the count data. Here, if the count data corresponding to each unit in the RAM 13 is decreased every time the pulse signal is output from the photosensor after the intermediate transfer belt 41 makes one rotation, simply when the intermediate transfer belt 41 rotates 15 times, The count data immediately becomes "0" and the remaining life of each unit is erroneously detected. Therefore, in this embodiment, the pulse data from the photo sensor is accumulated, and the count data in the RAM 13 is rewritten each time it is confirmed that the intermediate transfer belt 41 has rotated a predetermined number of times. Further, the count data in the RAM 13 is written into the EEPROM of the unit as needed.

Here, in this embodiment, since the count data is constituted by the ring code shown in FIG. 3, the count data becomes 1 in accordance with the pulse signal from the photo sensor.
At the time of the reduction, the number of the 16 divided data constituting the count data, that is, only two changed divided data among the ring code values R15 to R0 change, and the other divided data do not change. For example, if the count data is "15"
When the remaining life of the unit is reduced by decreasing from "1" to "14", the ring code value R15 changes from "1" to "0" and the ring code value R14 changes from "0" to "1".
, And the remaining ring code values R13 to R0 remain "0".

Therefore, in this embodiment, the RAM 13
When writing the count data in the data into the EEPROM, only the changed variable divided data of the divided data is written in the EEPROM.
The data is serially transferred to the OM to update the data. For example, as described above, the count data is changed from “15” to “1”.
When the number is reduced to "4", as shown in FIG. 5, two serial transfers are performed, and the first is: a write command (010) + address 4 bits (1111) + data 1 bit (0), a total of 8 bits of serial data. The second transfer: a serial transfer of a total of 8 bits of the write command (010) + the address 4 bits (1110) + the data 1 bit (1) is performed in this order to execute the data update of the EEPROM. After that, as shown in the figure, the data in the EEPROM is updated by performing two serial transfers in the same manner as described above.

As described above, in this embodiment, the count code indicating the remaining life of the unit is composed of 16 divided data, and only a part of the plurality of divided data is EE.
By serially transferring to the PROM side, EEPR
Since the count data in the OM is rewritten, all the count values are compared to the conventional device that serially transfers all count values.
Count data stored in a storage element such as an EPROM can be updated in a short time.

It is also possible to simply divide the count data into a plurality of divided data and serially transfer only the variable divided data whose remaining life has changed with the progress of the image forming process. By configuring the data with a ring code, more excellent operational effects can be obtained. This point will be described in detail in comparison with a comparative example in which the count data is configured by a binary code.

In this comparative example, the count data is composed of a 4-bit binary code as shown in FIG. Therefore, in this comparative example, a serial EEPROM is used.
The (storage element) is provided with four 1-bit storage areas, and, as in the above-described embodiment, a command of 3 bits +
A total of 8 bits of address 4 bits + data 1 bit is 1
Serial transfer is possible as a unit of communication.

Also in this comparative example, the same data as the count data previously stored in each unit is stored in the RAM 13, and the count data in the RAM 13 is reduced in accordance with the execution of the image forming process. At the same time, the count data in the RAM 13 is written into the EEPROM of the unit as needed.

Here, in this comparative example, since the count data is constituted by the binary code shown in FIG. 4, the count data becomes 1 in accordance with the pulse signal from the photo sensor.
At the time of the decrease, the number of the divided data constituting the count data, that is, the variable divided data that changes among the binary code values B3 to B0 is one at a minimum and four at a maximum. For example, when the count data decreases from "15" to "14" and the remaining life of the unit is shortened, the count code value B0 changes from "1" to "0" and the remaining count code values B3 to B1 remains at "1".
Accordingly, in this case, as shown in FIG. 6, one serial transfer, the first: serial transfer of a total of 8 bits of write command (010) + address 4 bits (0000) + data 1 bit (0) is performed. Then, the data of the EEPROM is updated.

However, when the count data decreases from "8" to "7" and the remaining life of the unit is shortened, all the count code values B3 to B0 change. Therefore, in this case, four serial transfers, the first: a write command (010) + the address 4 bits (0000) + the data 1 bit (1), a total of 8 bits of serial transfer, and the second: the write command (010) + 8-bit serial transfer of address 4 bits (0001) + 1-bit data (1); 3rd: Write command (010) + 4-bit address (0010) + 1-bit data (1) for a total of 8 bits Serial transfer, the fourth time: a write command (010) + address 4 bits (0011) + data 1 bit (0), a total of 8 bits of serial transfer, are performed in this order, and the EEPROM data is updated.

As described above, in the comparative example, it is necessary to perform a maximum of four serial transfers. If the data transfer time per transfer is, for example, 5 ms, the maximum data transfer time is 20 m.
s.

On the other hand, according to the present embodiment, as shown in FIG. 5, the data update of the EEPROM can be performed by performing the serial transfer twice in any case, and the maximum data transfer time can be obtained. Can be reduced to 10 ms.

In this type of image forming apparatus, as is well known in the art, even if the power is turned off during the update operation, the power supply must be turned off during the update operation in order to surely complete the update process. The power supply is configured so that the voltage is maintained at a voltage that allows normal updating. Therefore, the period during which the voltage must be maintained is shortened by shortening the data transfer time, and the power supply cost can be reduced.
This is advantageous in terms of equipment cost. That is, according to the present embodiment, the data transfer time can be shortened as compared with the comparative example, and the device cost can be effectively reduced.

In the above embodiment, the case where the count data changes one by one has been described. However, the same is true even when the amount of change is two or more. That is,
Even when the count data changes from "15" to "13", only the ring code values R15 and R13 change, since the count data is composed of the ring code (FIG. 3). The ring code value of is unchanged. Therefore, the update process can be performed by two serial transfers.

In the above embodiment, the count data is constituted by the ring code (FIG. 3). In addition to the ring code, at least one or more of the plurality of divided data is changed due to a change in the count data. It can be composed of a code that does not change. One example is a gray code. Therefore, a case where the count data is configured by a gray code will be described in detail below.

FIG. 7 is a diagram showing a gray code employed in another embodiment of the image forming apparatus according to the present invention. This Gray code is a code in which the hamming distance of two adjacent numbers is 1, as shown in FIG. 3, for example, when the count data changes from “0” to “1”, Least significant code value (bit)
Only G0 changes from "0" to "1", and the remaining code values (bits) G1 to G15 do not change. Therefore,
In this embodiment, the count data composed of a gray code is divided into two divided data of an upper byte and a lower byte, and a serial EEPROM (storage element) is divided into two storage areas each composed of one byte (8 bits). Provided. Then, if necessary, only the divided data including the changed code value is serially transferred according to the flowchart shown in FIG. 8, and the divided data is written in the corresponding memory area. For other configurations,
Since this embodiment is the same as the above-described embodiment, the same reference numerals are given and the description of the configuration is omitted.

FIG. 8 is a flowchart showing the updating process when the count data is constituted by the gray code.
First, the count data indicating the remaining life stored in the RAM 13 is copied to a memory space (hereinafter abbreviated as “TEMP”) for temporarily storing (step S1).
Then, the pulse signal from the photo sensor is accumulated, and every time it is confirmed that the intermediate transfer belt 41 has rotated a predetermined number of times, the count data during TEMP is reduced by 1 (step S2). Here, in this embodiment,
Since the count data is composed of gray code,
In the Gray codes G15-G0, only one bit changes, which is included in only one of the upper byte and the lower byte.

Therefore, in the next step S3, TEMP
The lower byte in the middle is compared with the lower byte of the count data stored in the RAM 13, and when they match, there is no change in the bits constituting the lower byte.
It is determined that one of the bits constituting the upper byte of the MP has changed, and the upper byte is serially transferred to the EEPROM collectively in, for example, a write cycle shown in FIG.
The transmitted data is overwritten on the upper byte of the count data stored in the EPROM, and the remaining life is rewritten (step S4). Further, the count data is updated by overwriting the upper byte of the data between the RAM 13 and the upper byte of the TEMP (step S5).

On the other hand, if the lower byte in the TEMP does not match the lower byte of the count data stored in the RAM 13 in step S3, there is no change in the bits constituting the upper byte, and the lower byte of the TEMP is not changed. Is determined to have changed, and the lower byte is overwritten as in steps S4 and S5. That is, for example, in the write cycle shown in FIG.
The transmitted data is overwritten on the lower byte of the count data stored in the EPROM, and the remaining life is rewritten (step S6). Also, the count data is updated by overwriting the lower byte of the data between the RAM 13 and the lower byte of the TEMP (step S7).

As described above, according to this embodiment, the count code indicating the remaining life of the unit is composed of two divided data (upper byte + lower byte), and only one of the plurality of divided data is stored in the EEPROM. Side, the count data in the EEPROM is rewritten, so that the count data is stored in the EEPROM as compared with the conventional device in which all the count values are serially transferred.
Data can be stored in a storage element such as an OM in a short time.

For example, as described in Japanese Patent Application Laid-Open No. 2000-172133, when serially transferring the entire count data, as shown in FIG. 10, for example, the chip select signal CS is set to H for the data transfer time, and The input data DI is input in synchronization with the clock signal SK.
1), addresses A7 to A0, and data D15 to D0. After such data transfer, memory writing is performed in the EEPROM. Therefore, assuming that the time required for serial transfer of bytes is t and the time required for writing in the storage element is T, at least (4t + T) is required for updating and storing the count data.

On the other hand, according to this embodiment, FIG.
As shown in (1), since the amount of data to be transferred is reduced by one byte, for updating and storing the count data,
Only the time (3t + T) is required, and the time t can be reduced. In particular, in this embodiment, the count data is 2
It consists of bytes, but the number of bytes is arbitrary,
can be composed of m bytes (m is an integer of 2 or more),
The degree of freedom in setting the count data can be improved. Moreover, even if the number of bytes is increased, the time required for updating and storing the count data is (3t +
T).

In the above embodiment and the conventional example, since the count data has a 2-byte structure, the minimum value of the count data is "0" and the maximum value is "65".
535 ". Therefore, in the conventional example, every time the count data decreases by one, it is necessary to access all the addresses in the EEPROM where the count data is stored and rewrite the data, and the number of accesses to the same address is 65,535. In the embodiment, the address of the upper byte is 255 times, and the address of the lower byte is 65280 (= 65535).
-255) times. As described above, according to the present embodiment, the number of accesses to the EEPROM can be suppressed, and an EEPROM having a small number of rewritable times can be employed. Therefore, the cheaper EEPRO
M can be used, and the cost of the apparatus can be reduced.

The present invention is not limited to the above-described embodiment, and various changes other than those described above can be made without departing from the gist of the present invention. For example, in the above embodiment, the number of divisions of the count data is 2, 4, and 16, but the number of divisions is not limited to this, and may be an integer of 2 or more.

In the above embodiment, the storage area for storing the count data is provided in the EEPROM corresponding to the count data.
No. 33, a storage area of n times (n is an integer of 2 or more) is provided, and each time the count data is updated, the variable divided data is stored in n storage areas corresponding to the variable divided data. May be sequentially written.

The image forming apparatus according to the above embodiment is a printer that prints an image given from an external device such as a host computer on sheets such as copy paper, transfer paper, paper, and a transparent sheet for OHP. The present invention can be applied to all electrophotographic image forming apparatuses, including copying machines and facsimile machines.

[0055]

As described above, according to the present invention, the count data is composed of a plurality of divided data, and when changing according to a signal, at least one of the plurality of divided data is divided. When the count data changes based on the signal, the variable divided data that changes before and after the change becomes a part of the plurality of divided data because it is configured with a code that does not change. Since only the variable division data is serially transferred to the storage means and written into the storage means, the count data can be updated and stored in the storage element in a short time.

[Brief description of the drawings]

FIG. 1 is a diagram showing one embodiment of an image forming apparatus according to the present invention.

FIG. 2 is a block diagram illustrating an engine controller of the image forming apparatus of FIG. 1;

FIG. 3 is a diagram illustrating count data (ring code) employed in the image forming apparatus.

FIG. 4 is a diagram showing count data (binary code) employed in a comparative example.

FIG. 5 is a diagram illustrating an operation of updating count data to an EEPROM in the image forming apparatus.

FIG. 6 is a diagram illustrating an operation of updating count data in an EEPROM in a comparative example.

FIG. 7 is a diagram showing count data (gray code) employed in the image forming apparatus.

FIG. 8 is a flowchart illustrating an update process when count data is configured by a gray code.

FIG. 9 shows EEPRO count data (gray code)
6 is a timing chart showing a write cycle for writing data into M.

FIG. 10 shows a conventional apparatus that counts data by EEPR.
5 is a timing chart showing a write cycle for writing data into an OM.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Engine controller (control means) 11 ... CPU (control means) 71-77 ... Serial EEPROM (storage element) G0-G15 ... Gray code R0-R15 ... Ring code

 ──────────────────────────────────────────────────続 き Continuing on the front page F term (reference) 2C061 AP01 AP03 AP04 AQ06 AR01 2H027 DA32 DA45 DD07 DD09 DE04 DE07 DE09 EA15 EB04 EC06 EC09 EC10 EC18 ED01 ED08 ED24 ED25 EE01 EE02 EE08 EF09 HB02 HB05 HB13 HB07 HB13 HB05 QA15 5B060 CB03 DA08

Claims (10)

[Claims] 1. A storage element for electrically storing count data, and a control for changing the count data based on a signal generated in the device and writing the count data to the storage element by serial transfer Means, the control means divides the count data into a plurality,
When only the variable divided data including the bit changed according to the signal among the divided data is serially transferred to the storage element and written into the storage element, and the count data is changed according to the signal. ,
An image forming apparatus comprising a code such that at least one of the plurality of divided data does not change. 2. The storage element has the same number of storage areas as the number of divisions of the count data, and the control means receives the signal and updates the variable division every time the count data is updated. 2. The image forming apparatus according to claim 1, wherein the data is written into a storage area corresponding to the variable division data. 3. The storage element has a storage area of n times the number of divisions of the count data (n is an integer of 2 or more), and n storage areas are associated with each division data. 2. The image forming apparatus according to claim 1, wherein the control unit sequentially writes the variable division data into n storage areas corresponding to the variable division data each time the count data is updated in response to the signal. apparatus. 4. The image forming apparatus according to claim 1, wherein said storage element is constituted by a nonvolatile memory. 5. The image forming apparatus according to claim 1, further comprising at least one or more replacement units, wherein each of said replacement units is provided with said storage element. 6. The image forming apparatus according to claim 5, wherein the count data is information indicating a use state of the replacement unit. 7. The image forming apparatus according to claim 1, wherein said count data is constituted by a gray code. 8. The storage element is an m-byte (m is an integer of 2 or more) non-volatile memory, and the control means divides the count data into m pieces, and responds to the signal among the divided data. 8. The image forming apparatus according to claim 7, wherein only the variable division data including the changed bit is serially transferred to the storage element and written to the storage element. 9. The image forming apparatus according to claim 1, wherein said count data comprises a ring code. 10. An information updating method for changing count data based on a signal generated in an image forming apparatus and writing the count data to a storage element by serial transfer, wherein the count data is divided into a plurality of pieces. The plurality of divided data are configured so that at least one of the plurality of divided data does not change when the divided data changes according to the signal. An information updating method in the image forming apparatus, wherein only the variable division data including the changed bit is serially transferred to the storage element and written to the storage element.