KR20130028608A - Crum chip and image forming device for communicating mutually, and method thereof - Google Patents

Abstract

PURPOSE: A CRUM(Customer Replaceable Unit Monitoring) chip, an image forming device, and a communication method thereof are provided to record accurate data by generating integrity inspecting data. CONSTITUTION: When data is generated, a main controller of an image forming device or a CRUM chip of a consumables unit generates integrity inspecting data by using the generated data(S910,S920). The main controller or the CRUM chip transmits a signal including the generated integrity inspecting data and the data(S930). The main controller or the CRUM chip receives a response signal corresponding to the transmitted signal(S940). The main controller or the CRUM chip executes an integrity inspecting process by using the integrity inspecting data included in the response signal(S950). [Reference numerals] (AA) Start; (BB) End; (S910) Generating data to be transferred; (S920) Generating integrity inspecting data; (S930) Transmitting signals; (S940) Receiving response signals; (S950) Integrity inspecting using the integrity inspecting data included in the response signals

Description

CRUM chip and image forming device and communicating method {CRUM chip and image forming device for communicating mutually, and method

The present invention relates to a CRUM chip, an image forming apparatus, and a communication method thereof, and more particularly, to a CRUM chip, an image forming apparatus, and a communication method of checking integrity using integrity check data in a communication process.

As computer dissemination is activated, the dissemination rate of computer peripherals is increasing day by day. Representative examples of computer peripherals include image forming apparatuses such as printers, facsimiles, scanners, copiers, multifunction devices, and the like.

Image forming apparatuses use ink or toner to print an image on paper. Ink or toner is used each time an image forming operation is performed, and is depleted when used for a predetermined time or more. In this case, the unit itself that stores the ink or toner must be replaced. As such, the parts or components that can be replaced in the process of using the image forming apparatus are called consumable units or replaceable units. For convenience of description, the name consumable unit is used herein.

In addition to the units to which the consumable unit is depleted in ink or toner as described above, there are also units that are replaced for reasons that the characteristics thereof are changed when used for a certain period of time, and thus a good print quality cannot be expected. That is, in addition to the developer for each color, components such as an intermediate transfer belt may also correspond to the consumable unit.

Specifically, in the case of a laser image forming apparatus, a charging unit, a transfer unit, a fixing unit, and the like are used, and various kinds of rollers, belts, etc. used in each unit may be worn or deteriorated when they are used for longer than the life limit. As a result, the image quality can be significantly reduced. The user must replace each component unit, that is, the consumable units, at an appropriate replacement time so that the printing operation can be performed with a clean image.

Recently, in order to properly manage the consumable unit, a memory is attached to the consumable unit itself so as to exchange information with the main body of the image forming apparatus.

That is, various usage information such as the number of prints of the image forming apparatus, the number of output dots, the expiration date, etc. are recorded in the memory of the consumable unit itself, so that the replacement time of the consumable unit can be accurately managed.

In order to manage such information, the main controller provided in the main body of the image forming apparatus and the memory unit provided in the consumable unit communicate with each other. However, there can be many variables in the communication process. For example, there may be noise interference generated by an electronic circuit or a motor provided in the image forming apparatus, or a hacker may attempt to control the main controller or the memory unit for malicious purposes.

Due to these variables, communication data may change. For example, when the job is completed, the consumable unit transfers information such as the number of printed pages, the number of dots, the amount of remaining toner, etc. to the main controller and copies it to the nonvolatile memory of the main controller. In this case, if the data is read with an incorrect value such as 0xFFFFFFFF, there is a risk that the main controller will recognize that the consumable unit has reached the end of its life. In this case, the consumable unit can no longer be used. Conversely, even for a consumable unit that has reached the end of its life, a hacker may reset the consumable use information to zero for malicious purposes, thereby making the consumable unit reproducible. As a result, a consumable unit that has reached the end of its life may be used, which may cause problems such as failure of the image forming apparatus and deterioration of image quality.

Accordingly, there is a need for a technology capable of efficiently checking the communication error between the consumable unit and the image forming apparatus to improve data stability.

An object of the present invention is to provide a CRUM chip, an image forming apparatus, and a communication method thereof capable of achieving communication safety using integrity check data.

According to an embodiment of the present invention for achieving the above object, the CRUM chip that can be mounted in the consumable unit of the image forming apparatus, the first data and the first integrity check data for the first data from the main body of the image forming apparatus; An interface unit for receiving a first signal comprising a, the inspection unit for separating the first integrity test data from the first signal, to check the integrity of the first signal, the second to be transmitted to the main body of the image forming apparatus A data processor for generating data, a generator for generating second integrity check data using the second data and the first integrity check data, and a second signal including the second data and the second integrity check data And a controller for controlling the interface unit to transmit the data to the main body of the image forming apparatus.

Here, when it is determined that the first signal is integrity, a temporary storage unit for temporarily storing the data and the first integrity check data included in the first signal, and a storage unit for recording data temporarily stored in the temporary storage unit. It may further include.

On the other hand, the inspection unit generates data to be compared using the remaining data included in the first signal, compares the second integrity check data and the comparison target data separated from the second signal, and if the match It can be determined that the second signal is integrity, and if there is a mismatch, it can be determined as an error state.

On the other hand, when the third signal including the third integrity check data generated by cumulatively reflecting the second integrity check data is received through the interface unit, the checker performs an integrity check on the third signal,

When the image forming job is completed, the integrity of the entire signal received in the process of performing the image forming job may be finally inspected using the final integrity check data included in the signal received last in the process of performing the image forming job.

In this case, when it is determined that the entire signal is integrity, the controller may store data temporarily stored in the temporary storage unit in the storage unit.

The first data or the second data may include a command, recording target information, operation performance result information according to the command, integrity check result information about a previous received signal, and indicator information for indicating a location of the integrity check data. At least one,

The integrity check result information may be excluded from a signal initially transmitted to the CRUM chip.

The integrity check data may be a result of performing a logical operation on the data, a result generated by applying a preset equation to the data, or an encryption result of encrypting the data.

On the other hand, according to an embodiment of the present invention, the communication method of the CRUM chip that can be mounted on the consumable unit of the image forming apparatus, the first data and the first integrity check data for the first data from the main body of the image forming apparatus Receiving a first signal comprising a, Checking step of separating the first integrity check data from the first signal, to check the integrity of the first signal, If it is determined that the first signal is integrity, the first Temporarily storing the data included in the signal and the first integrity check data; generating second data when the second data to be transmitted to the main body of the image forming apparatus exists; And generating second integrity check data using the first integrity check data and including the second data and the second integrity check data. And transmitting a second signal to the main body of the image forming apparatus.

Here, the checking may include separating the first integrity check data from the first signal, generating data to be compared using the remaining data included in the first signal, and separating the second signal from the first signal. The method may further include comparing the second integrity check data with the comparison target data and determining that the second signal is integrity if there is a match and determining an error state if there is a mismatch.

And when the third signal including the third integrity check data generated by accumulating the second integrity check data is received from the main body of the image forming apparatus, performing the integrity check on the third signal. It may further include.

In addition, when the image forming job is completed, using the final integrity check data included in the signal received last in the process of performing the image forming job, the final inspection of the integrity of the entire signal received in the process of performing the image forming job, If it is determined that the entire signal is integrity as a result of the final test, the method may further include storing the signals temporarily stored in the temporary storage.

The first data or the second data may include a command, recording target information, operation performance result information according to the command, integrity check result information about a previous received signal, and indicator information for indicating a location of the integrity check data. It may include at least one.

In this case, the integrity check result information may be excluded from the signal initially transmitted with the CRUM chip.

The integrity check data may be a result of performing a logical operation on the data, a result generated by applying a preset equation to the data, or an encryption result obtained by encrypting the data.

As described above, according to various embodiments of the present disclosure, it is possible to accumulate use of the integrity check data used in the previous communication to secure the safety of the entire communication. Accordingly, the information of the consumable unit and the image forming apparatus can be safely managed.

1 is a block diagram showing the configuration of an image forming apparatus according to an embodiment of the present invention;
2 is a timing diagram illustrating a communication process between a main controller and a CRUM chip in an image forming apparatus according to an embodiment of the present invention;
3 is a timing diagram for explaining in detail the process of checking the integrity of a signal using the integrity check data;
4 is a timing diagram illustrating a communication process between a main controller and a CRUM chip in an image forming apparatus according to another embodiment of the present invention;
5 is a block diagram showing the configuration of an image forming apparatus equipped with a consumable unit;
6 and 7 are block diagrams illustrating a configuration of an image forming apparatus according to various embodiments of the present disclosure;
8 is a block diagram showing a configuration of a CRUM chip according to an embodiment of the present invention;
9 and 10 are flowcharts illustrating a communication method according to various embodiments of the present disclosure.

Hereinafter, the present invention will be described in detail with reference to the accompanying drawings.

1 is a block diagram illustrating a configuration of an image forming apparatus according to an exemplary embodiment. According to FIG. 1, the image forming apparatus includes a main body 100, a main controller 110 provided in the main body 100, and a consumable unit 200 mountable to the main body 100. Here, the image forming apparatus may be implemented as various types of devices capable of forming an image on paper or various recording media such as a printer, a scanner, a multifunction printer, a facsimile machine, a copying machine, and the like.

The main controller 110 is mounted on the main body 100 of the image forming apparatus to control the overall functions of the image forming apparatus.

The consumable unit 200 may be mounted on the main body 100 of the image forming apparatus, and may be various types of units directly or indirectly involved in the image forming job. For example, in the case of a laser image forming apparatus, a charging unit, an exposure unit, a developing unit, a transfer unit, a fixing unit, various rollers, a belt, an OPC drum, and the like may be consumable units. In addition, in the use of the image forming apparatus, Various types of units requiring replacement may be defined as the consumable unit 200.

As described above, each lifespan is determined in the consumable unit 200. Therefore, the consumable unit 200 includes a customer replaceable unit monitoring chip (CRUM chip) 210 so that replacement can be made at an appropriate time.

The CRUM chip 210 is mounted on the consumable unit 200 and records various types of information. The CRUM chip 210 includes a memory. Accordingly, the CRUM chip 210 may be referred to by various names such as a memory unit, a customer replaceable unit monitoring memory (CRUM memory), etc., but for convenience of description, the CRUM chip 210 will be described as a CRUM chip 210.

The memory provided in the CRUM chip 210 may store various characteristic information about the consumable unit 200, the CRUM chip 210 itself, the image forming apparatus, and the like, and use information or a program related to performing an image forming job.

Specifically, various programs stored in the CRUM chip 210 may include not only general applications but also O / S (Operating System) programs, encryption programs, and the like. In addition, the characteristic information includes information on the manufacturer of the consumable unit 200, information on the manufacturer of the image forming apparatus, a device name of the image forming apparatus that can be mounted, information on manufacturing date, serial number, model name, electronic signature information, An encryption key, an encryption key index, and the like may be included. In addition, the usage information may include information on how many sheets have been printed so far, how many sheets can be printed, and how much toner is left. The characteristic information may alternatively be called unique information.

For example, the CRUM chip 210 may store information as shown in the following table.

General Information OS Version
SPL-C Version
Engine Version
USB Serial Number
Set model
Service Start Date CLP300_V1.30.12.35 02-22-2007
5.24 06-28-2006
6.01.00 (55)
BH45BAIP914466B.
DOM
2007-09-29 Option RAM Size
EEPROM Size
USB Connected (High) 32 Mbytes
4096 bytes
Consumables Life Total Page Count
Fuser life
Transfer roller life
Tray1 Roller Life
Total Image Count
Imaging Unit / Deve Roller Life
Transfer belt life
Toner image count 774/93 Pages (Color / mono)
1636 Pages
864 Pages
867 Pages
3251 Images
61 Images / 19 Pages
3251 Images
14/9/14/19 Images (C / M / Y / K) Toner information Toner Remains Percent
Toner Average Coverage 99% / 91% / 92% / 100% (C / M / Y / K)
5% / 53% / 31% / 3% (C / M / Y / K) Consumables Information Cyan toner
Magenta toner
Yellow toner
Black toner
Imaging unit SAMSUNG (DOM)
SAMSUNG (DOM)
SAMSUNG (DOM)
SAMSUNG (DOM)
SAMSUNG (DOM) Color Menu Custom color Manual Adjust (CMYK: 0,0,0,0) Setup Menu Power save
Auto Continue
Altitude Adj. 20 Minutes
On
Plain

As shown in the above table, the memory of the CRUM chip 210 may store not only the general information on the consumable unit 200 but also information on the life of the consumable unit, information, a setup menu, and the like. The memory may also store O / S provided for use in the consumable unit separately from the main body of the image forming apparatus.

In addition, the CRUM chip 210 may further include a CPU (not shown) that manages the memory, executes various programs stored in the memory, and communicates with a controller of the main body of the image forming apparatus or other devices. .

The CPU may drive the O / S stored in the memory of the CRUM chip 210 to perform initialization of the consumable unit 200 itself apart from the initialization of the image forming apparatus. The CPU may also perform authentication with the main body of the image forming apparatus during initialization or during initialization. In addition, after authentication is completed, encrypted data communication may be performed with the main body of the image forming apparatus. In this case, various commands and data transmitted from the image forming apparatus main body may be encrypted and transmitted according to an arbitrary encryption algorithm.

Specifically, the CPU is configured to return to the main body 100 of the image forming apparatus after a specific event, for example, when the power of the image forming apparatus on which the consumable unit 200 is mounted is turned on or when the consumable unit 200 is detached. In the case of installation, the initialization may be performed independently of the initialization of the main controller 110. Initialization includes initial operation of various application programs used in the consumable unit 200, calculation of secret information required for data communication with the main controller 110 after initialization, communication channel setup, memory value initialization, self-exchange time confirmation, and consumable unit 200 This includes various steps such as setting internal register values and setting internal and external clock signals.

Here, the register value setting refers to an operation of setting the function register values inside the consumable unit 200 to operate the consumable unit 200 corresponding to various functional states previously set by the user. In addition, the internal and external clock signal setting refers to an operation of adjusting the frequency of the external clock signal provided from the main controller 110 of the image forming apparatus to match the internal clock signal used by the CPU in the consumable unit 200.

In addition, the self-replacement time confirmation may be a task for identifying the remaining amount of toner or ink used up to this time, predicting when the end will be exhausted, and notifying the main controller 110 side. Accordingly, when it is determined that the remaining amount of toner is already exhausted in the initialization process, after the initialization is completed, the consumable unit 200 may be implemented to notify the main controller 110 of the inoperable state by itself. In addition, since the consumable unit 200 has its own O / S, various types of initialization may be performed according to the type and characteristic of the consumable unit 200.

As such, when the CPU is built in and has its own O / S, it is stored in the memory unit 210 before the main controller 110 requests communication with the unit 200 when the image forming apparatus is powered on. You can check the remaining amount of consumables and the number of refills. Accordingly, the time for notifying the shortage of consumables can be much faster than before. For example, when the toner is low, the user can switch to the toner saving mode immediately after power-on to perform image formation. The same is true when only a specific toner is low.

The CPU does not respond to the command of the main controller 110 until the initialization is completed. The main controller 110 waits for a response while periodically transmitting a command until there is a response.

Accordingly, when a response, that is, acknowledgment is received, authentication is performed between the main controller 110 and the CPU. In this case, due to its own O / S installed in the CRUM chip 210, authentication through interaction between the CRUM unit 210 and the main controller 110 becomes possible.

Specifically, the main controller 110 encrypts data or commands for authentication and transmits the encrypted data or commands to the CRUM chip 210. The transmitted data may include any value R1. Here, R1 may be a random value that is changed at every authentication or may be a fixed value arbitrarily set. The CRUM chip 210 receiving the data generates a session key using a random value R2 and the received R1 and generates a message authentication code (MAC) using the generated session key. Accordingly, the signal including the generated MAC and R2 is transmitted to the main controller 110. The main controller 110 generates a session key using the received R2 and R1, generates a MAC using the generated session key, and then compares the generated MAC with the MAC included in the received signal. 210 is authenticated. Meanwhile, according to various embodiments of the present disclosure, electronic signature information or key information may be transmitted and received in the authentication process and used for authentication.

If authentication is successful, the main controller 110 and the CRUM chip 210 perform encrypted data communication for data management. That is, when a user command is input, or an image forming job is started or completed, the main controller 110 uses an encryption algorithm for a command or data for performing data reading, writing, or the like. After encryption, the data is transmitted to the CRUM chip 210. The CRUM chip 210 may decode the received command or data and perform operations such as data reading and writing corresponding to the command. The encryption algorithm used in the CRUM chip 210 or the main controller 110 may be a standard encryption algorithm. This encryption algorithm can be changed if the encryption key is disclosed or if security needs to be enhanced. Specifically, various encryption algorithms such as RSA asymmetric key algorithm, ARIA, TDES, SEED, AES symmetric key algorithm, and the like may be used.

As such, multiple communications for authentication and data exchange may be performed between the CRUM chip 210 and the main controller 110. In each communication, a signal is transmitted from the main controller 110 to the CRUM chip 210 or vice versa. In this case, the transmitted signal includes error detection data for checking the integrity of the data included in the signal. The integrity check data is generated by accumulating and reflecting the integrity check data included in the signal transmitted or received during the previous communication.

That is, as described above, between the main controller 110 and the CRUM chip 210, authentication 1, authentication 2, authentication 3, ..., authentication n, data communication 1, data communication 2, ... Likewise, a plurality of communications can be performed. The signal transmitted at each communication includes integrity check data. The integrity check data cumulatively reflects the integrity check data used in the previous communication. Specifically, it demonstrates in the drawing part mentioned later.

The receiving side checks the integrity of the signal using the integrity check data included in the signal. Accordingly, when it is determined that the signal is integrity, the data and integrity check data included in the signal are temporarily stored. Then, new integrity check data is generated using the subsequent data to be transmitted to the transmitter side and the integrity check data stored in the immediately preceding communication and temporarily stored. Accordingly, a signal in which new integrity check data is added to subsequent data is transmitted. The communication including the integrity check data is performed a plurality of times between the main controller 110 and the CRUM chip 210. If the last communication is made, a final check is performed using the integrity check data included in the last received signal. If there is no abnormality as a result of the final inspection, all the data temporarily stored until then is recorded.

2 is a timing diagram illustrating a communication process between the main controller 110 and the CRUM chip 210 according to an embodiment of the present invention. According to FIG. 2, the main controller 110 transmits a first signal 10 including data 1 and integrity check data 1. The CRUM chip 210 receiving the first signal 10 generates the integrity check data 2 using the integrity check data 1 and the data 2 included in the first signal 10. Then, a second signal including data 2 and integrity check data 2 is transmitted to the main controller 110. As such, the signals 30,..., N including the integrity check data generated by using the integrity check data in the previous communication are performed a plurality of times.

The integrity check data may be a result of performing a logical operation on the data to be transmitted, a result generated by applying a preset equation to the data, or an encryption result obtained by encrypting the data, that is, a MAC.

3 is a view for explaining a test method using the integrity check data. According to FIG. 3, when a signal including data a and integrity check data a is received from the main controller 110 (S310), the CRUM chip 210 separates the integrity check data a (S320).

Thereafter, the integrity check data a 'is generated using the remaining data and the integrity check data transmitted during the previous communication (S330). The integrity check data a 'generated accordingly is compared with the separated integrity check data a (S340), and if it matches, it is determined as integrity (S350). On the other hand, if there is a mismatch, it is determined as an error state and the communication is stopped (S360). For convenience of explanation, hereinafter, the integrity check data a 'is referred to as data to be compared.

When it is determined as integrity, the integrity check data b is generated using the data b to be transmitted and the integrity check data a (S370). Accordingly, the signal including the data b and the integrity check data b is transmitted to the main controller 110 (S380).

In FIG. 3, the inspection process performed in the CRUM chip 210 has been described, but the same process may be performed in the main controller 110. That is, when the signal including the data b and the integrity check data b is received, the main controller 110 separates the integrity check data b and performs a check. Since the inspection method is the same as that of S330 to S370, overlapping description and illustration are omitted.

Meanwhile, the configuration of signals transmitted and received between the main controller 110 and the CRUM chip 210 may be variously designed. That is, the data included in the signal may include at least one of a command, recording target information, work performance result information according to a command, integrity check result information on a previous received signal, and indicator information for indicating a location of the integrity check data. . In this case, the integrity check result information may be excluded from a signal initially transmitted between the main controller 110 and the CRUM chip 210.

FIG. 4 is a diagram for describing a process of checking integrity using a signal having a different format from that of FIG. 2. According to FIG. 4, the main controller 110 transmits a signal including data and integrity check data 1 (S410). Here, the data includes read command data 1 (Read command (CMD) data 1) and the indicator U1. The read command data 1 includes not only a command but also a read target or a memory address. U1 means indicator information following the read command data 1. The indicator information U1 means a symbol for indicating a parsing position of the integrity check data in the signal. The indicator information may be represented by a fixed number of bytes. For example, 5 bytes may be used for indicator information. On the other hand, the size of the read command data 1 is variable according to the content of the data, and thus, the size of the integrity check data 1 is also variable.

When the CRUM chip 210 receives a signal, the CRUM chip 210 performs an integrity check by using the integrity check data 1 included in the signal (S415). Then, after generating integrity check data 2 using the data to be transmitted and integrity check data 1, a signal including them is transmitted (S420). As shown in FIG. 4, the transmitted signal includes read data 1 which is data read from a memory provided in the consumable unit 100 according to the read command data 1, and an operation performed according to the read command data 1. Result data 2 indicating the result, indicator U2, and integrity check data 2 are included.

The main controller 110 separates the integrity check data 2 from the received signal and performs an integrity check (S425). When the subsequent read command data 3 exists, the integrity check data 3 is generated using the read command data 3 and the integrity check data 2, and then a signal including the read command data 3, the indicator U3, and the integrity check data 3 is generated. Transmitted to the CRUM chip 210 (S430). After that, as shown in FIG. 4, communication using a plurality of integrity check data 4, 5, 6, T1, and T2 is performed (S440, S450, S460, S470, and S485), and thus integrity check is performed. (S435, S445, S455, S465). On the other hand, when the CRUM chip 210 receives the last communication signal (S470), the CRUM chip 210 transmits and receives data temporarily stored in the entire communication process using the integrity check data T1 included in the last communication signal. Final integrity check (S475). If it is determined that the integrity is the final test result, the temporarily stored data is stored in a nonvolatile memory (not shown) (S480). Similarly, when the last communication signal is also transmitted from the CRUM chip 210 (S485), the main controller 110 also performs a full integrity check using the integrity check data T2 included in the last communication signal (S490). Accordingly, if it is determined that the integrity, the temporarily stored data is stored in the nonvolatile memory (S495).

Meanwhile, the integrity check data used in this communication process is generated by accumulating and reflecting the integrity check data used in the previous communication.

For example, the integrity check data may be processed as follows.

Integrity Check Data 1 = E (Read CMD Data 1 | U1)

Integrity check data 2 = E (Read CMD Data 2 | Result Data 2 | U2 | Integrity check data 1)

Integrity Check Data 3 = E (Read CMD Data 3 | U3 | Integrity Check Data 2)

Integrity check data 4 = E (Read CMD Data 4 | Result Data 4 | U4 | Integrity check data 3)

Integrity Check Data 5 = E (Write CMD Data 5 | U5 | Integrity Check Data 4)

Integrity check data 6 = E (Result Data 6 | U6 | Integrity check data 5)

Integrity check data T1 = E (Write CMD Data L1 | U-T1 | Integrity check data T1-1)

Integrity check data T2 = E (Result Data L2 | U-T2 | Integrity check data T1)

In the above formulas, E () means a function of applying a preset formula to obtain a result value. As such, the integrity check data may be applied to various logical operations such as summation, XOR (eXclusive OR), etc. for the entire integrity check data and the entire data to be transmitted, or data in other formulas known between the main controller 110 and the CRUM chip 210. It can be generated as a result calculated by substituting the result, the result obtained by applying a variety of encryption algorithms described above.

5 illustrates a configuration of an image forming apparatus in which a plurality of consumable units 200-1, 200-2,..., 200-n are mounted in the main body 100, according to an embodiment of the present disclosure.

According to FIG. 5, the image forming apparatus includes a main controller 110, a user interface unit 120, an interface unit 130, a memory unit 140, and a plurality of consumable units 200-1, 200-2,. 200-n).

The user interface unit 120 receives various commands from the user, or displays various types of information. The user interface 120 may include an LCD or LED display, at least one button, a speaker, or the like, and in some cases, may include a touch screen.

The interface unit 130 refers to a configuration for communicating with a host PC or various external devices by wire or wirelessly. The interface unit 130 may include various types of interfaces such as a local interface, a universal serial bus (USB) interface, a wireless network interface, and the like.

The memory unit 140 stores various programs, data, and the like necessary for driving the image forming apparatus.

The main controller 110 controls the overall operation of the image forming apparatus. Specifically, the main controller 110 processes the data received through the interface unit 130 and converts the data into a format capable of forming an image.

Then, the main controller 110 performs an image forming job on the converted data using the plurality of consumable units 200-1, 200-2, ..., 200-n. The consumable unit may be provided in various ways according to the type of the image forming apparatus. As described above, in the case of a laser printer, a charging unit, an exposure unit, a developing unit, a transfer unit, a fixing unit, various rollers, a belt, an OPC drum, or the like may be a consumable unit.

Meanwhile, each of the consumable units 200-1, 200-2,..., 200-n includes first to n-th CRUM chips 210-1, 210-2,..., 210-n. Each is included.

Each CRUM chip may include a memory and a CPU. Alternatively, according to an embodiment, a crypto unit, a temper detector, an interface unit, a clock unit for outputting a clock signal (not shown), or a random value generator for generating a random value for authentication may be used. At least one of (not shown) may be further included.

The crypto unit (not shown) supports an encryption algorithm so that the CPU (not shown) can perform authentication or encrypted communication with the main controller 110. Specifically, the crypto unit may support an algorithm set among four encryption algorithms such as ARIA, TDES, SEED, and AES symmetric key algorithm. In this case, the main controller 110 may also support a corresponding algorithm among four encryption algorithms. Accordingly, the main controller 110 may identify what encryption algorithm is used in the consumable unit 200, perform authentication with the encryption algorithm, and then perform encryption communication. As a result, even if a key to which any encryption algorithm is applied is issued to the consumable unit 200, it is easily mounted on the main body 100 of the image forming apparatus to perform encrypted communication.

A temper detector (not shown) is a unit for defending various physical hacking attempts, i.e., tempering. Specifically, it monitors the operating environment such as voltage, temperature, pressure, light, and frequency, and erases or physically disconnects data when there is an attempt such as Decap. In this case, the temper detector may have a separate power supply.

The memory provided in the CRUM chip 210 may include an O / S memory, a nonvolatile memory, a volatile memory, and the like. An O / S memory (not shown) stores an O / S for driving the consumable unit 200. In the nonvolatile memory (not shown), various data are stored nonvolatile. The nonvolatile memory includes electronic signature information, various encryption algorithm information, status information of the consumable unit 200 (for example, toner remaining amount information, replacement time information, remaining print quantity information, etc.), unique information (for example, a manufacturer). Information, manufacturing date and time information, serial number, product model name, etc.), and after-sales information may be stored. In particular, data received during the communication with the main controller 110 may be stored in the nonvolatile memory.

Volatile memory (not shown) may be used as a temporary storage space required for operation. In the volatile memory, data determined as integrity and integrity check data used for the determination may be temporarily stored in every communication.

The interface unit (not shown) serves to connect the CPU and the main controller 110. Specifically, it may be implemented as a serial interface or a wireless interface. In particular, since the serial interface uses a smaller number of signals than the parallel interface, the serial interface can reduce costs, and is particularly suitable for a noisy operating environment such as a printer.

As described above, each consumable unit may be provided with a CRUM chip. Each CRUM chip can communicate with the main controller and other CRUM chips. In communication, new integrity check data generated by accumulating and reflecting integrity check data used in previous communication is transmitted.

6 is a block diagram illustrating a detailed configuration example of an image forming apparatus according to an exemplary embodiment. According to FIG. 6, the image forming apparatus includes a main controller 110 and an interface unit 130, and the main controller 110 includes a data processor 111, a generator 112, an inspector 113, and a controller 114. ).

The data processing unit 111 generates data to be transmitted to the CRUM chip mounted in the consumable unit mountable in the image forming apparatus. Here, the data includes at least one of a command and information to be processed by the command. That is, in the case of a read command, information about a memory address to be read or a read target may be transmitted together. In the case of a write command, information to be recorded may be transmitted together. The data processor 111 may output the data as it is or encrypted. In addition, various commands such as a command for authentication and information related to the command may be generated in the data processor 111. Such commands and information may be generated from time to time before, during or after the execution of the image forming job. For example, when the image forming apparatus is turned on or when the consumable unit 200 is detached and remounted, or when a start command for the image forming job is input, the main controller 110 may execute the consumable unit 200. An authentication command or a lead command may be transmitted for authentication. Accordingly, various types of information managed in the consumable unit 200 may be checked and authenticated, or may be stored in the memory unit 140 of the main body of the image forming apparatus 100.

In addition, during or after the image forming job is executed, the data processing unit 111 supplies consumables consumed in the image forming job, that is, information about ink or toner, the number of printed pages, the number of printed dots, In order to record the history information and the like in the consumable unit 200, a write command and corresponding information may be generated.

The generation unit 112 generates integrity check data using the data output from the data processing unit 111. Specifically, the data output from the data processing unit 111 is simply summed, a logical operation such as XOR is performed, substituted into a preset equation, or encrypted using an encryption algorithm, and the result value is integrity check data. You can output In this case, if the integrity check data used in the previous communication exists, the integrity check data is generated by cumulatively reflecting the existing integrity check data.

The integrity check data generated by the generator 112 is added to the data generated by the data processor 111 and transmitted to the interface unit 130. In FIG. 6, the output of the data processing unit 111 is illustrated as being provided only to the generation unit 112, but the output of the data processing unit 111 may be provided directly to the interface unit 130 or may be provided to a multiplexer (not shown). have. When the multiplexer is provided, the output of the generator 112 may also be provided to the multiplexer, and may be delivered to the interface unit 130 in the form of a signal including data and integrity check data.

The interface unit 130 transmits a signal including the data and the first integrity check data to the CRUM chip 210.

In addition, the interface unit 130 may receive a response signal from the CRUM chip 210. For convenience of description, a signal transmitted from the interface unit 130 is called a first signal, and a signal received from a CRUM chip is called a second signal. The second integrity check data included in the second signal is data generated by cumulatively reflecting the first integrity check data.

The inspection unit 113 separates the second integrity check data included in the second signal received through the interface unit 130 and checks the integrity of the data included in the second signal. Specifically, the inspection unit 113 is known between the CRUM chip 210 and the remaining data from which the second integrity inspection data is separated and the integrity inspection data previously transmitted by the main controller 110. Apply the method to generate integrity check data.

The integrity check data generated accordingly and the second integrity check data separated from the second signal are compared to confirm whether there is a match. If the result of the check matches, the inspecting unit 113 determines that the data is integrity, and if not, the check unit 113 determines that the data is in an error state.

The control unit 114 performs subsequent communication according to the inspection result of the inspection unit 114. That is, when it is determined that the second signal includes data in an error state, subsequent communication may be stopped or retried. On the other hand, if it is determined that the second signal is in a normal state, that is, an integrity state, subsequent communication is performed.

According to an embodiment, if it is determined that the integrity state, the controller 114 may directly store the corresponding data in the memory unit 140.

According to another embodiment, the data and integrity check data obtained may be temporarily stored in every communication, and the temporarily stored data may be recorded in the memory unit 140 when the final communication is completed.

7 shows a configuration of an image forming apparatus according to this embodiment. According to FIG. 7, the memory controller 140 may be further included in addition to the main controller 110 and the interface unit 130 including the data processor 111, the generator 112, the inspector 113, and the controller 114. . The memory unit 140 includes a temporary storage unit 141 and a storage unit 142.

Accordingly, the data determined to be integrity and integrity check data may be temporarily stored in the temporary storage unit 141. The temporarily stored integrity check data can be used during the integrity check of the data in a subsequent communication process.

That is, when the second signal for the first signal is transmitted after the first signal including the first integrity check data is transmitted to the CRUM chip 210 as described above, the inspection unit 113 may generate a second signal from the second signal. 2 The integrity check data is separated, and new integrity check data, that is, comparison target data is generated using the remaining check data and the integrity check data stored in the temporary storage unit 141. Then, the inspection unit 113 may compare the generated new integrity check data with the second integrity check data in the temporary storage unit 141 to determine the integrity of the second signal or the data included in the second signal.

Meanwhile, if there is subsequent data to be transmitted to the CRUM chip 210 while the second signal is integrity, the generation unit 112 generates third integrity check data based on the subsequent data and the second integrity check data. Accordingly, the interface unit 130 transmits a third signal including the third integrity check data and subsequent data to the CRUM chip 210. That is, as described with reference to FIGS. 2 to 4, the main controller 110 and the CRUM chip 210 communicate several times.

On the other hand, when one image forming job is completed, the inspection unit 113 uses the final integrity check data included in the signal received last during the image forming job to perform the integrity of the entire signal received during the image forming job. Can be final tested. That is, as described above, since the integrity check data transmitted and received at each communication is generated by accumulating and reflecting the previous integrity check data, the final integrity check data includes all of the first integrity check data and the previous integrity check data. Therefore, when it is determined that the data is integrity using the final integrity check data, it is determined that the reliability of the entire communication contents is reliable and all the temporarily stored data are stored in the storage unit 142 in the memory unit 140.

On the other hand, the main controller 110 and the CRUM chip 210 includes the signal indicating that the first communication in the first communication in the first communication, and transmits the signal indicating the final communication in the signal during the final communication. Accordingly, the main controller 110 and the CRUM chip 210 store the data in the storage unit 142 by performing the above-mentioned final inspection when the final communication indication is confirmed on the signal received from the counterpart.

This final inspection may be performed when one image forming job is completed, or may be performed in predetermined time periods according to an embodiment. Also, the operation may be performed when a user command for data storage is input or when a turn-off command for the image forming apparatus is input.

In addition, although the data processor 111, the generator 112, the inspector 113, and the controller 114 are included in the main controller 110 in FIGS. 6 and 7, the present invention is not limited thereto. That is, at least one of the data processor 111, the generator 112, the inspector 113, and the controller 114 may be provided separately from the main controller 110. In this case, unlike the description of FIGS. 1 to 4, the main controller 110 performs only the original function and communication with the CRUM chip 210 is performed by the data processor 111, the generator 112, the inspector 113, It may be performed by the control unit 114 or the like.

8 is a block diagram illustrating a configuration of a CRUM chip 210 according to an embodiment of the present invention. According to FIG. 8, the CRUM chip 210 includes an interface unit 211, an inspection unit 212, a generation unit 213, a data processing unit 214, a control unit 215, a temporary storage unit 216, and a storage unit 217. ).

The interface unit 211 receives a first signal including first data and first integrity check data for the first data from a main body of the image forming apparatus, in particular, the main controller 110 mounted in the main body.

The inspection unit 212 separates the first integrity check data from the first signal and checks the integrity of the first signal. Since the inspection method of the inspection unit 212 has been described above, a redundant description thereof will be omitted.

When it is determined that the first signal is integrity, the temporary storage unit 216 temporarily stores the first data and the first integrity check data.

The data processor 214 generates the second data when the second data to be transmitted to the main body of the image forming apparatus exists.

The generation unit 213 generates the second integrity check data by using the generated second data and the first integrity check data.

The controller 215 controls the interface unit to transmit a second signal including the second data and the second integrity check data to the main body of the image forming apparatus. In addition, the controller 215 controls the overall operation of the CRUM chip 215. That is, when the CRUM chip has its own O / S as described above, the controller 215 may drive the CRUM chip using the O / S. In particular, if the initialization program is stored, the initialization may be performed separately from the main body of the image forming apparatus.

In addition, the controller 215 may perform tasks corresponding to various commands received from the main body of the image forming apparatus. That is, when a read command is received, data stored in the storage unit 217 is read and transmitted to the image forming apparatus through the interface unit 211 according to the command. In this process, integrity check data may be added.

Meanwhile, when the third signal including the third integrity check data generated by cumulatively reflecting the second integrity check data is received through the interface unit 211, the check unit 212 performs an integrity check on the third signal. To perform.

When the image forming job is completed, the final integrity check of the entire signal received in the image forming job is finally inspected using the final integrity check data included in the signal received last in the image forming job.

As a result of the check, if the communication is completed in an integrity state, the data temporarily stored in the temporary storage unit 216 are stored in the storage unit 217.

That is, when communication is finally terminated, the controller 215 controls the inspection unit 212 to perform a final inspection using the last integrity check data. Accordingly, when the final inspection result of the inspection unit 212 is determined to be integrity, the control unit 215 stores the data temporarily stored in the temporary storage unit 216 in the storage unit 217.

The operation of the CRUM chip 210 of FIG. 8 is also similar to that of the image forming apparatus of FIG. 7. That is, the main controller 110 of the image forming apparatus and the CRUM chip 210 of the consumable unit 200 perform operations corresponding to each other as described with reference to FIGS. 1 to 4. Therefore, both sides should be provided with an algorithm that generates integrity check data and checks the data in common.

9 is a flowchart illustrating a communication method according to an embodiment of the present invention. The communication method illustrated in FIG. 9 may be performed by the main controller 110 provided in the main body of the image forming apparatus, or may be performed by the CRUM chip 210 provided in the consumable unit 200.

According to FIG. 9, when data to be transmitted is generated (S910), integrity check data is generated using the generated data (S920). Since the generation of the integrity check data has been described above, a detailed description thereof will be omitted.

Then, a signal including the generated integrity check data and data is transmitted (S930).

Accordingly, a response signal corresponding to the transmitted signal is received from the counterpart (S940). The response signal includes new integrity check data generated by accumulating and reflecting the integrity check data transmitted from S930.

Accordingly, the integrity check is performed using the integrity check data included in the response signal (S950).

As such, according to the simple application of the present invention, the integrity of each communication can be determined by accumulating the previous integrity check data.

10 is a flowchart illustrating a communication method according to a more specific embodiment. According to FIG. 10, when data to be transmitted is generated (S1010), integrity check data is generated based on the data (S1020). Then, a signal including data and integrity check data is transmitted (S1030), and a response signal for the signal is received (S1040). Accordingly, the integrity check data is separated from the response signal (S1050).

Then, the integrity check data is determined using the remaining data from which the integrity check data is separated and the existing integrity check data (S1060).

If the determination result is integrity, it is temporarily stored (S1070), if it is an error state, the communication is stopped (S1100) or retry is performed.

On the other hand, if there is subsequent data in the temporarily stored state (S1080), the above-described steps are repeatedly performed. On the other hand, if there is no subsequent data, according to the integrity check result of the last received signal, temporarily stored data is stored (S1090).

In various embodiments as described above, the integrity check data is generated by accumulating and reflecting the integrity check data of the previous communication except for the integrity check data transmitted from the main controller of the image forming apparatus when the data communication is first started. As a result, the integrity check data in the final communication includes all the integrity check data used in the entire communication process. Therefore, accurate data can be recorded.

As a result, information on the main controller and the CRUM chip can be safely protected from external factors such as noise, bad contact, and hacking that occur during communication.

Meanwhile, in the above-described embodiments, the CRUM chip mounted on the image forming apparatus and the consumable unit used in the apparatus has been described, but the above-described communication method may be applied to other types of apparatuses. For example, communication between a CRUM chip and a device manufactured for communication with a CRUM chip, not an image forming device, communication between a general electronic device and a memory mounted on a part used in the device, communication between parts It is apparent that the contents of the present invention can also be applied to and the like.

The program for performing the communication method according to various embodiments of the present disclosure described above may be stored and used in various types of recording media.

Specifically, the code for performing the above-described methods may include random access memory (RAM), flash memory, read only memory (ROM), erasable programmable ROM (EPROM), electronically erasable and programmable ROM (EEPROM), registers, hard drives. It may be stored in various types of recording media readable by the terminal, such as a disk, a removable disk, a memory card, a USB memory, a CD-ROM, and the like.

While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it is to be understood that the invention is not limited to the disclosed exemplary embodiments, but, on the contrary, It will be understood by those skilled in the art that various changes in form and detail may be made therein without departing from the spirit and scope of the present invention.

100: main body 110: main controller
200: consumable unit 210: CRUM chip

Claims (12)

A CRUM chip mountable on a consumable unit of an image forming apparatus,
An interface unit for receiving a first signal including first data and first integrity check data for the first data from a main body of the image forming apparatus;
A checker configured to check the integrity of the first signal by separating the first integrity check data from the first signal;
A data processor for generating second data to be transmitted to the main body of the image forming apparatus;
A generation unit configured to generate second integrity check data by using the second data and the first integrity check data;
And a controller configured to control the interface unit to transmit a second signal including the second data and the second integrity check data to a main body of the image forming apparatus. The method of claim 1,
A temporary storage unit that temporarily stores the data and the first integrity check data included in the first signal when it is determined that the first signal is integrity; And
And a storage unit for recording data temporarily stored in the temporary storage unit. The method of claim 2,
Wherein,
The comparison target data is generated using the remaining data included in the first signal, and the second integrity check data separated from the second signal is compared with the comparison target data. CRUM chip, characterized in that judging, if the mismatch is determined to be an error state. The method of claim 3,
Wherein,
When the third signal including the third integrity check data generated by cumulatively reflecting the second integrity check data is received through the interface unit, the integrity check is performed on the third signal.
When the image forming job is completed, the final integrity check of the entire signal received in the process of performing the image forming job is performed by using the final integrity check data included in the signal received last in the process of performing the image forming job,
The control unit,
And if it is determined that the entire signal is integrity, the CRUM chip stores data temporarily stored in the temporary storage unit in the storage unit. 5. The method according to any one of claims 1 to 4,
The first data or the second data,
At least one of a command, recording target information, work performance result information according to the command, integrity check result information about a previous received signal, and indicator information for indicating a location of the integrity check data,
And the integrity check result information is excluded from a signal initially transmitted to the CRUM chip. The method of claim 5,
The integrity check data is a CRUM chip, characterized in that the result of the logical operation of the data, the result generated by applying a predetermined equation to the data or the encryption result of encrypting the data. In the communication method of the CRUM chip attachable to the consumable unit of the image forming apparatus,
Receiving a first signal including first data and first integrity check data for the first data from a main body of the image forming apparatus;
Checking the integrity of the first signal by separating the first integrity check data from the first signal;
If it is determined that the first signal is integrity, temporarily storing the data and the first integrity check data included in the first signal;
Generating second data when there is second data to be transmitted to the main body of the image forming apparatus;
Generating second integrity check data using the second data and the first integrity check data; And
And transmitting a second signal including the second data and the second integrity check data to a main body of the image forming apparatus. The method of claim 7, wherein
The inspection step,
Separating the first integrity check data from the first signal;
Generating data to be compared using the remaining data included in the first signal;
And comparing the second integrity check data separated from the second signal with the comparison target data, determining that the second signal is integrity if there is a match, and determining an error state if there is a mismatch. CRUM chip communication method. 9. The method of claim 8,
Performing an integrity check on the third signal when a third signal including the third integrity check data generated by accumulating the second integrity check data is received from the main body of the image forming apparatus; Communication method of the CRUM chip comprising a. 10. The method of claim 9,
When the image forming job is completed, using the final integrity check data included in the signal received last during the image forming job, finally checking the integrity of the entire signal received during the image forming job;
And storing the signals that have been temporarily stored in the temporary storage unit if the entire signal is determined to be integrity. The method according to any one of claims 7 to 10,
The first data or the second data,
At least one of a command, recording target information, work performance result information according to the command, integrity check result information about a previous received signal, and indicator information for indicating a location of the integrity check data,
The integrity check result information is excluded from the signal initially transmitted with the CRUM chip. The method of claim 11,
The integrity check data is a communication result of a CRUM chip, characterized in that the logical result of the data, the result generated by applying a predetermined equation to the data or the encryption result value encrypted the data.

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