JP2008225972A - Image forming apparatus, data protection method, and program - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a technique for protecting a specific program in rewriting the program which makes an image forming apparatus uncontrollable when breakage or erasing occur. <P>SOLUTION: The image forming apparatus 100 includes a storage medium 102 such as a flash memory divided into a plurality of partitions. The specific program is stored in any one of the partitions. A switching processing part 111 switches the partition to be accessed, and a rewrite processing part 11 rewrites the specific program stored in a first partition 103 by copying this specific program to a second partition 104 different from the first partition 103 by switching by the switching processing part 111 and then storing an update program in the first partition 103. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to an image forming apparatus, and more particularly to a technique for protecting a specific program.

  In recent years, storage media capable of rewriting data, such as flash memory, have come to be used in many print controllers in image forming apparatuses such as printers because of a reduction in cost.

  The flash memory includes, for example, a boot program, a rewrite program for rewriting data in the memory, an I / F (interface) control program for transmitting / receiving data to / from various peripheral devices, a program for performing print control, etc. Is stored.

  These programs are required to be rewritten in accordance with function expansion, version upgrade as a security measure, user customization, and the like. For example, Patent Document 1 describes a technique for easily updating a control program for a printer apparatus.

JP-A-7-314798

  However, when a specific program such as a boot program, a rewrite program, or an I / F program is destroyed or erased, the image forming apparatus cannot be controlled. Therefore, it is necessary to prevent the program from being destroyed or erased during the rewriting process of these programs.

  It is an object of the present invention to provide a technique for protecting a specific program that makes the image forming apparatus uncontrollable when it is destroyed or erased, when the program is rewritten.

  In order to solve the above problems, the present invention is an image forming apparatus to which a host computer having an update program is connected, and the image forming apparatus includes a plurality of partitions. An instruction receiving unit that includes a storage medium in which a specific program for controlling the image forming apparatus is stored, receives an instruction to rewrite the specific program, and a switching process for switching which partition of the plurality of partitions is accessed And when the instruction is received, the specific program stored in any of the partitions differs from the first partition in which the specific program is stored by switching of the switching processing unit Duplicate to the second partition and before Get the update program from the host computer, and having obtained the rewriting processing unit for storing the update program to the first partition and the.

  According to the image forming apparatus of the present invention, when rewriting a specific program that makes the image forming apparatus uncontrollable when it is destroyed or erased, the program can be protected.

  The best mode for carrying out the present invention will be described below with reference to the drawings.

  An example of the hardware configuration of the image forming apparatus 100 applied to the embodiment of the present invention is shown in the block diagram of FIG.

  A host PC 200 is connected to the image forming apparatus 100. The image forming apparatus 100 generates print data based on the image data sent from the host PC 200. The image forming apparatus 100 prints the generated print data using a print engine 300 to be described later. Further, the image forming apparatus 100 has a specific program (hereinafter referred to as an uncontrollable program) that makes the image forming apparatus 100 uncontrollable when destroyed or erased. Then, the main program is rewritten. Here, the main program is, for example, a rewriting program for rewriting the main program itself, a starting program for starting / restarting the system of the image forming apparatus 100, and an I / for receiving various programs from the host PC 200. F control program.

  Further, the image forming apparatus 100 protects the main program when the main program is rewritten.

  The image forming apparatus 100 can accept a new main program for rewriting from the host PC 200 or the like. The new main program for rewriting may be, for example, a program in which bugs are corrected, a program with expanded functions, a program with improved security, or the like. The purpose of rewriting the main program here is to upgrade the so-called main program. Therefore, the image forming apparatus 100 rewrites the main program by overwriting the upgraded main program on the main program already incorporated in the image forming apparatus 100.

  The host PC 200 is a general information processing apparatus such as a personal computer. For example, the host PC 200 adds a command instructing printing to the generated image data to be printed and transmits the image data to the image forming apparatus 100. In addition, the host PC 200 transmits various programs such as a main program to the image forming apparatus 100. Although the image forming apparatus 100 is described as being connected to one host PC 200 in FIG. 1, a plurality of host PCs 200 may be connected via a network or the like.

  The image forming apparatus 100 as described above includes a control unit 101, a storage medium 102, an I / F (interface) unit 105, a print engine 106, and an input unit 107.

  The storage medium 102 is a memory that can rewrite data, such as a flash memory. The storage medium 102 stores, for example, the main program described above, a program for image processing and printing processing in the image forming apparatus 100, and the like.

  Further, a sector address is assigned to the storage medium 102 as shown in FIG. Access to each sector in the storage medium 102 is performed by designating each sector address.

  Furthermore, the storage medium 102 is divided into two partitions, block A103 and block B104. Here, the two partitions may be physical partitions obtained by electrically dividing the storage medium 102 in units of partitions, or may be logical partitions obtained by software division. Here, the sector address is, for example, an 11-bit numeric string such as “01010011111”. Further, for example, an address whose upper 1 bit is 0 is assigned to the block A103, and an address whose upper 1 bit is 1 is assigned to the block B104.

  In the storage medium 102, the main program described above is stored in at least one of the blocks A103 and B104. A specific description of this will be described later.

  As described above, the main program includes the rewriting program, the activation program, and the I / F control program. However, the image forming apparatus 100 reads the activation program from either the block A 103 or the block B 104 in the main program. The data for starting block specification for specifying whether or not it was started in is included. The main program also includes start address specifying data for specifying the start addresses of the blocks A103 and B104 (for example, the address A1 and the address B1 shown in FIG. 2).

  Further, the storage medium 102 stores various programs such as a program for the image forming apparatus 100 to generate print data and a program for performing print processing.

  In addition, the checksum value of the data stored in each block is stored in the sector to which the final address of each block (block A103, block B) is assigned.

  Returning to FIG. 1, the I / F unit 105 is an interface that accepts connection of the host PC 200 and transmits / receives various data to / from the host PC 200. The I / F unit 105 is also an interface that accepts connection of an input unit 107 (to be described later) and receives various data from the input unit 107. For example, the I / F unit 105 may be a USB interface compliant with the USB standard. However, the I / F unit 105 is not limited to a USB interface, and may be a network interface for connecting to a network such as a LAN, for example.

  The input unit 107 is an operation panel for receiving instructions from the user. Here, the input unit 107 accepts a start / restart instruction, a main program rewriting instruction, a printing instruction, various function setting instructions, and the like from the user. Specifically, the input unit 107 has one or a plurality of operation buttons and the like, and generates a corresponding instruction signal based on the operation of the button by the user. The input unit 107 supplies the generated instruction signal to the control unit 101 via the I / F unit 105.

  The print engine 106 performs printing on printing paper based on the serial data (print data) input from the control unit 101. For example, if the print engine 106 is a laser printer, the print engine 106 includes a laser irradiation mechanism, a photosensitive drum, a paper feed mechanism, and the like.

  The control unit 101 reads out various programs stored in the storage medium 102, a switching process for switching the activation block of the storage medium 102, a rewriting process for rewriting various programs stored in the storage medium 102, and the image forming apparatus 100. Performs startup processing to start the system. In addition, the control unit 101 performs processing for receiving input data supplied from the host PC 200 and the input unit 107 via the I / F unit 105. Further, the control unit 101 generates print data based on the image data supplied from the host PC 200. The control unit 101 causes the print engine 106 to print the generated print data.

  As shown in FIG. 1, the control unit 101 that performs the above processing includes a switching processing unit 110, a rewrite processing unit 111, an activation processing unit 112, an I / F control unit 113, an image processing unit 114, and a printing process. And a control unit 115.

  The switching processing unit 110 performs processing for switching the activation block of the storage medium 102. For example, the switching processing unit 110 includes an address switching processing unit 300, an address switching register 301, a timer 302, a decoder 303, and an OR circuit 304, as shown in FIG.

  The decoder 303 is a storage medium that the control unit 101 accesses when the control unit 101 accesses the storage medium 102 (for example, when the rewrite processing unit 111 rewrites data stored in the storage medium 102). An address on 102 is generated. For example, when the control unit 101 rewrites the main program stored in the storage medium 102, the decoder 303 generates addresses A1 to A12 where the main program is stored. At this time, the decoder 303 supplies the generated addresses A1 to A12 to the address switching processing unit 300.

  The address switching processing unit 300 is a circuit that determines whether or not to convert the address supplied from the decoder 303 with reference to data stored in an address switching register 301 described later. In the case of conversion, the address switching processing unit 300 converts the address supplied from the decoder 303 and supplies the converted address to the storage medium 102. When not converting, the address switching processing unit 300 supplies the address supplied from the decoder 303 to the storage medium 102 without converting. Here, in the address conversion, for example, the upper 1 bit of the address (11-bit numeric string) supplied from the decoder 303 is inverted. As a result, the address switching processing unit 300 converts the addresses A1 to A12 supplied from the decoder 303 into addresses B1 to B12. In addition, the address switching processing unit 300 can also convert the addresses B1 to B12 supplied from the decoder 303 into addresses A1 to A12.

  The address switching register 301 stores data for specifying a block of the storage medium 102 accessed by the control unit 101. For example, this data may be data such as “0” and “1”. Here, for example, when the data stored in the address switching register 301 is “0”, the control unit 101 accesses the block A103 of the storage medium 102, and when it is “1”, it accesses the block B104. To do.

  The data stored in the address switching register 301 is rewritable. For example, the control unit 101 can change (write) data in the address switching register 301. Further, based on the notification from the timer 302, the data stored in the address switching register 301 is changed.

  Further, the control unit 101 can specify the activation block at that time by referring to (reading) the data in the address switching register 301.

  The timer 302 determines the timing for switching the activation block of the storage medium 102. For example, the timer 302 receives a notification from the activation processing unit 112 and starts a counting operation based on a clock signal (not shown) with a fixed period supplied from a CPU described later. The timer 302 stops the counting operation when a predetermined time (for example, 1 minute) elapses without receiving a notification to stop the counting operation. However, the predetermined time is set in advance according to the time required to normally finish the system startup process. The count operation is also terminated when a notification for stopping the count operation is received from the activation processing unit 112 during the count operation. When the count operation is stopped, the timer 302 supplies a signal (for example, a high signal) indicating that the count operation is stopped to the address switching register 301 and the OR circuit 304.

  The OR circuit 304 is a circuit that supplies an instruction signal to the activation processing unit 112 by switching the activation block of the storage medium 102 and starting / restarting upon receiving a notification from either the timer 302 or the activation processing unit 112 It is. Specifically, the OR circuit 304 supplies a High signal to the activation processing unit 112 when any of the signals supplied from the activation processing unit 112 and the timer 302 is High.

  With the configuration as described above, the switching processing unit 110 can perform switching of blocks that access the storage medium 102 and switching of activation blocks. In the present embodiment, the switching processing unit 110 has been described as a hardware configuration. However, the present invention may be implemented by software.

  Returning to FIG. 1, the rewrite processing unit 111 performs a process of rewriting various programs stored in the storage medium 102. For example, the rewrite processing unit 111 rewrites the above-described main program stored in the storage medium 102, a program for image processing, print processing, and the like.

  Specifically, before rewriting various programs stored in the storage medium 102, the rewrite processing unit 111 accesses the address switching register 301 of the switching processing unit 110 and specifies the activation block at that time. Keep it. The rewrite processing unit 111 reads the program to be rewritten stored in the identified block, and temporarily copies the read program to a block different from the identified block. After the copying is normally completed, the rewrite processing unit 111 acquires a new rewrite program. At this time, a program to be newly rewritten is acquired from the host PC 200 via the I / F unit 105 and the I / F control unit 113, for example. The rewrite processing unit 111 compares the acquired new program with the program to be rewritten and, when it is necessary to rewrite, the program stored in the same block as the activation block specified earlier is Rewrite. Here, the rewrite processing unit 111 determines whether the rewrite has been normally performed and ends the rewrite process. The determination at this time is performed, for example, by calculating a checksum. Each time the above-described duplication processing and rewriting processing are performed, the rewriting processing unit 110 updates the checksum value stored in the final address of each block (block A103, block B104).

  By the rewriting process, the image forming apparatus 100 can protect the main program from being destroyed or erased when the main program is rewritten.

  The activation processing unit 112 activates and restarts the system in the image forming apparatus 100. For example, the activation processing unit 112 receives an activation / reactivation instruction from the input unit 107 when the timer 302 of the switching processing unit 110 described above times out (when the activation process cannot be performed normally). In the event of a failure, system startup / reboot processing is performed. Here, the activation of the system refers to performing initial setting of the system (such as drive processing of the print engine 106) so that the image forming apparatus 100 can perform printing.

  Specifically, the activation processing unit 112 notifies the timer 302 of the switching processing unit 110 when the power is turned on by hardware, and causes the timer 302 to start a counting operation. Then, the startup processing unit 112 accesses the address switching register 301 of the switching processing unit 110 and identifies the startup block at that time before performing the system startup / restart processing. When the activation block is normal, the activation processing unit 112 performs system activation / reactivation processing. However, upon receiving a time-out notification from the timer 302 before the system startup / restart processing is completed, the startup processing unit 112 switches the startup block to a block different from the current startup block, and the system Restart. In addition, the activation processing unit 112 supplies a signal for stopping the count operation to the timer 302 when the activation / reactivation processing is completed.

  As a result, in the image forming apparatus 100, the CPU described later can read the activation program from the block storing the normal main program, and can perform the activation / reactivation processing of the system.

  The I / F control unit 113 controls the I / F unit 105. For example, the I / F control unit 113 controls transmission / reception of data with the host PC 200 and the input unit 107 connected to the I / F unit 105. Specifically, when image data to be printed is supplied from the host PC 200 via the I / F unit 105, the I / F control unit 113 supplies the image data to the image processing unit 114 described later. . Further, when a signal instructing system activation / reactivation is supplied from the input unit 107, the I / F control unit 113 supplies the signal to the activation processing unit 112. Further, when a signal instructing rewriting of various programs stored in the storage medium 102 is supplied from the input unit 107, the I / F control unit 113 supplies the signal to the rewriting processing unit 111.

  The image processing unit 114 performs processing for converting image data to be printed supplied from the host PC 200 into print data that can be printed by the print engine 106. For example, the image processing unit 114 generates print data based on the image data supplied from the host PC 200 via the I / F control unit 113 and supplies the print data to the print control unit 115.

  The print control unit 115 performs processing for controlling the print engine 106. For example, the print control unit 115 supplies the print data generated by the image processing unit 114 to the print engine 106 and causes the print engine 106 to print.

  The image forming apparatus 100 configured as described above includes, for example, a CPU 401, a main storage device 402 such as a RAM, an ASIC 403 that performs specific processing, and an external storage device 405 such as a flash memory as illustrated in FIG. And a general printer including an input / output device 406 including an operation panel that receives an instruction from a user, a print engine that executes printing, and a communication device 404 that performs USB communication with the host PC 200. However, the communication device 404 may be a NIC (Network Interface Card) for connecting to a communication network.

  For example, the storage medium 102 described above can be realized by the external storage device 405. Further, the control unit 101 can be realized by loading various programs (main program, etc.) stored in the external storage device 405 into the main storage device 402 and processing them by the CPU 401 and the ASIC 403. Further, the I / F unit 105 and the I / F control unit 113 can be realized by the communication device 404. The input unit 107 and the print engine 106 are realized by an input / output device 406.

  With the configuration described above, the image forming apparatus 100 can protect the program from being destroyed or erased when the main program is rewritten.

  FIG. 5 is a flowchart for explaining a system start-up process performed by the image forming apparatus 100.

  The activation processing unit 112 of the control unit 101 in the image forming apparatus 100 is instructed to activate / restart when the system activation / reactivation process cannot be normally performed or when the user instructs the activation / reactivation via the input unit 107. When starting up, start-up processing is started. Specifically, the activation processing unit 112 starts the activation process when a High signal is supplied from the OR circuit 304 included in the switching processing unit 110 described above. For example, when the activation / reactivation of the system cannot be performed normally, the OR circuit 304 is notified that the timer 302 has timed out, and the OR circuit 304 supplies a high signal to the activation processing unit 112. In addition, when an activation / reactivation instruction is issued from the user, a signal generated by the input unit 107 based on the user's instruction is supplied to the activation processing unit 112 via the I / F control unit 113. At this time, the activation processing unit 112 supplies a High signal to the OR circuit 304, and the OR circuit 304 supplies a High signal to the activation processing unit 112.

  The activation processing unit 112 starts the activation process, and first activates the timer 302 (step S101). Specifically, the activation processing unit 112 supplies a high signal to the timer 302 indicating that the system activation process has started.

  At this time, the timer 302 receives a High signal from the activation processing unit 112 and performs counting according to clock pulses at regular intervals supplied from the CPU 401.

Subsequently, the activation processing unit 112 performs a process of specifying an activation block (step S102). Specifically, the activation processing unit 112 reads data stored in the address switching register 301 of the switching processing unit 110. If the read data is “0”, the activation processing unit 112 identifies the activation block as the block A103. In addition, when the read data is “1”, the activation processing unit 112 specifies that the activation block is the block B104.
Next, the activation processing unit 112 determines whether the activation block is invalid or the timer 302 activated in step S101 has timed out (step S103). Specifically, the activation processing unit 112 obtains a checksum value by scanning the activation block identified in step S102. The activation processing unit 112 performs the determination by comparing the obtained checksum value with the checksum value stored in the sector to which the final address of the activation block is assigned. Further, the activation processing unit 112 determines that a timeout has occurred when a signal notifying the timeout from the timer 302 is supplied via the OR circuit 304.

  In step S103, if the activation processing unit 112 determines that the activation block is normal and the timer 302 has not timed out (step S103; No), the process proceeds to step S104. On the other hand, if the activation processing unit 112 determines that the activation block is not normal or the timer 302 has timed out (step S103; Yes), the activation processing unit 112 shifts the processing to step S107. Specifically, the activation processing unit 112 shifts the process to step S104 when the checksum values compared in step S102 match without receiving a timeout notification from the timer 302, and if they do not match or times out If so, the process proceeds to step S107.

  Subsequently, the activation processing unit 112 starts a system activation / reactivation process (step S104). Specifically, the activation processing unit 112 performs initial settings for enabling the image forming apparatus 100 to print. Usually, this initial setting requires a predetermined time (for example, about 1 minute).

  At this time, the activation processing unit 112 determines whether or not the timer 302 activated in step S103 has timed out (step S105). Specifically, the activation processing unit 112 determines that a timeout has occurred when a signal notifying the timeout from the timer 302 is supplied via the OR circuit 304 during the initial setting.

  Note that the notification of the timeout of the timer 302 occurs when the initial setting of the system cannot be completed normally as described above. When the initial setting of the system requires a time exceeding the predetermined time (for example, about 1 minute), the processing is considered to be abnormal, and thus such a configuration is provided. With such a configuration, the image forming apparatus 100 can automatically detect an abnormality and switch the activation block when the system is activated.

  If it is determined in step S105 that a timeout has not occurred (step S105; Yes) and the system startup / restart process is completed (step S106; Yes), the startup processing unit 112 causes the timer 302 to stop the counting operation. To complete the startup process. Specifically, the activation processing unit 112 supplies a low signal to the timer 302 indicating that the system activation process has been completed. At this time, the timer 302 receives the Low signal and stops the count operation.

  On the other hand, in step S106, the activation processing unit 112 determines that the timer 302 has timed out (step S105; Yes) before ending the system activation / reactivation process (step S106; No). The process proceeds to S107.

  In step S106, the activation processing unit 112 may determine whether or not the system activation / reactivation process has been completed based on a result value returned when the activation program is terminated normally. Good.

  In step S107, the activation processing unit 112 causes the switching processing unit 110 to switch the activation block to a block different from the current activation block (step S107). Specifically, the data in the address switching register 301 is changed from “0” to “1” or from “1” to “0”. This change may be performed by the rewrite processing unit 111 when the timer 302 notifies the rewrite processing unit 111 of a timeout.

  In step S107, the activation processing unit 112 causes the switching processing unit 110 to switch the activation block, and then shifts the processing to step S101 to restart the system.

  By executing the above startup processing, the image forming apparatus 100 can perform system startup / restart processing from a block storing a normal program.

  FIG. 6 is a flowchart for explaining rewriting processing performed in the image forming apparatus 100.

  The rewrite processing unit 111 of the control unit 101 in the image forming apparatus 100 performs rewrite processing when an instruction to rewrite various programs stored in the storage medium 102 is received from the user via the input unit 107. To start. Specifically, when a signal generated by the input unit 107 based on a user instruction is supplied to the rewrite processing unit 111 via the I / F control unit 113, the rewriting process is started.

  As described above, it is not always necessary to start the rewriting process based on an instruction from the user, and the rewriting process is automatically performed according to a program for updating various programs stored in the storage medium 102. You may make it start.

  The rewrite processing unit 111 starts the rewriting process, and first performs a process of specifying the current activation block (step S201). Specifically, the rewrite processing unit 111 reads data stored in the address switching register 301 of the switching processing unit 110. When the read data is “0”, the rewrite processing unit 111 specifies that the activation block is the block A103. Further, when the read data is “1”, the rewrite processing unit 111 specifies that the activation block is the block B104.

  Subsequently, the rewrite processing unit 111 performs a process of copying the rewrite target program stored in the block identified in step S201 to the other block (step S202). Specifically, the rewrite processing unit 111 loads the rewrite target program stored in the block identified in step S201. After loading, the rewrite processing unit 111 changes the data in the address switching register 301 of the switching processing unit 110. Thereby, the block of the storage medium 102 which the rewriting process part 111 accesses can be switched. Then, the rewrite processing unit 111 copies the program to be rewritten previously loaded to the other block. At this time, the address switching processing unit 300 refers to the data stored in the previously-changed address switching register 301, inverts the upper 1 bit of the address supplied from the decoder 303, and accesses the access destination address. It works to specify.

  Next, the rewrite processing unit 111 determines whether or not the duplication in step S101 has been completed normally (step S203). Specifically, the rewrite processing unit 111 determines by comparing the checksum value of the program to be rewritten with the checksum value of the copied program.

  If the rewrite processing unit 111 determines in step S203 that the duplication has been completed normally (step S203; Yes), the process proceeds to step S204. On the other hand, when the rewrite processing unit 111 determines that the duplication has not ended normally (step S203; No), the process returns to step S202, and the duplication process is performed again. Specifically, the rewrite processing unit 111 shifts the process to step S204 when the compared chuck sum values match, and returns the process to step S202 when they do not match.

  In step S204, the rewrite processing unit 111 loads a new rewrite program (update program) (step S205). Specifically, the rewrite processing unit 111 loads the update program via the I / F control unit 113. At this time, the I / F control unit 113 communicates with the host PC 200 and supplies the update program to the rewrite processing unit 111. At this time, the update program to be acquired has data specifying the version in the header portion. Therefore, the host PC 200 can supply the latest update program to the I / F control unit 113 by referring to this version.

  Subsequently, the rewrite processing unit 111 determines whether or not the update program loaded in step S204 is a program that needs to be rewritten (step S205). Specifically, the rewrite processing unit 111 makes a determination by comparing the rewrite target program stored in the storage medium 102 with the data content of the update program.

  In step S205, when the rewrite processing unit 111 determines that rewriting is necessary (step S205; Yes), the process proceeds to step S206. On the other hand, when it is determined that there is no need to rewrite (step S205; No), the rewriting process is terminated. Specifically, the rewrite processing unit 111 shifts the process to step S206 when the compared data contents do not match, and ends the rewriting process when they match.

  In step S206, the rewrite processing unit 111 overwrites the program to be rewritten stored in the block identified in step S201 with the update program loaded in step S204 (step S206). Specifically, similarly to the processing described in step S202, first, the switching processing unit 301 switches the block accessed by the rewrite processing unit 111. Then, the rewrite processing unit 111 performs a process of writing the update program into the block after switching.

  If the update program is the main program, another program necessary for the printing process may be updated after overwriting the update program.

  Subsequently, the rewrite processing unit 111 determines whether or not the rewrite process has been normally completed (step S207). Specifically, the rewrite processing unit 111 makes a determination by comparing the checksum value of the upload program loaded in step S204 with the checksum value of the upload program stored in step S206.

  When it is determined in step S207 that the rewriting process has been normally completed, the rewriting processing unit 111 ends the rewriting process. On the other hand, if it is determined that the processing has not ended normally, the rewrite processing unit 111 returns the process to step S206 and performs the process of writing the update program again.

  By executing the above rewriting process by the image forming apparatus 100, when rewriting a program such as a main program, it is possible to protect the program from being destroyed or erased. For example, it is possible to prevent the image forming apparatus 100 from starting up due to a failure in rewriting the main program stored in the storage medium 102 when the power is turned off. In addition, when rewriting fails, the main program can be written again.

  Furthermore, the image forming apparatus 100 according to the present embodiment does not need to include a plurality of storage media 102 for main program backup, and thus is an inexpensive and highly reliable apparatus.

  In addition, this invention is not limited to the said embodiment, A various deformation | transformation and application are possible.

  For example, the rewrite processing unit 111 determines whether or not the update program loaded in step S204 is a program that needs to be rewritten by comparing data contents. However, the present invention is not limited to this, and the determination process in step S205 may be performed by comparing the version information described in the header part of the update program with the version of the program to be rewritten.

  In the above embodiment, the storage medium 102 is divided into two blocks. However, the present invention is not limited to this, and the storage medium 102 may be composed of a plurality of blocks such as three blocks and four blocks.

1 is a functional configuration diagram of an image forming apparatus according to an embodiment of the present invention. It is explanatory drawing for demonstrating the storage medium comprised from two partitions. It is a hardware block diagram of a switching process part. 2 is a diagram illustrating an example of a hardware configuration of an image forming apparatus. FIG. It is a flowchart for demonstrating the process at the time of starting. It is a flowchart for demonstrating the process at the time of rewriting.

Explanation of symbols

100 image forming apparatus, 101 control unit, 102 storage medium, 103 block A, 104 block B, 105 I / F unit, 106 print engine, 107 input unit, 110 switching processing unit, 111 rewrite processing unit, 112 activation processing unit , 113 I / F control unit, 114 image processing unit, 115 print control unit, 200 host PC, 300 address switching processing unit, 301 address switching register, 302 timer, 303 decoder, 304 OR circuit, 401 CPU, 402 main storage device , 403 ASIC, 404 communication device, 405 external storage device, 406 input / output device.

Claims (5)

An image forming apparatus to which a host computer having an update program is connected,
It is composed of a plurality of partitions, and a storage medium storing a specific program for controlling the image forming apparatus is provided in any one of the partitions,
An instruction receiving unit for receiving an instruction to rewrite the specific program;
A switching processing unit for switching which partition of the plurality of partitions is accessed;
When the instruction is received, a second program different from the first partition in which the specific program is stored by switching the specific processing program stored in any one of the partitions is changed. A rewrite processing unit that obtains an update program from the host computer after copying to a partition, and stores the obtained update program in the first partition;
An image forming apparatus comprising: An image forming apparatus according to claim 1,
The specific program includes a start program for starting the image forming apparatus,
The image forming apparatus includes a timer for timing after starting the processing of the startup program,
The switching processing unit
Before the end of the processing of the startup program, when the timer is notified that a predetermined time required for processing of the startup program has passed, the switching process is performed.
An image forming apparatus. The image forming apparatus according to claim 1, wherein:
The image forming apparatus includes a register that stores data for specifying one of a plurality of partitions,
The switching processing unit refers to the register and performs the switching.
An image forming apparatus. The image forming apparatus according to any one of claims 1 to 3,
The image forming apparatus includes a print processing unit that performs print processing.
The specific program includes a program for performing a printing process,
An image forming apparatus. The storage medium is a flash memory.
An image forming apparatus.

Images