JP5494134B2 - Control apparatus and control method - Google Patents

Description

  The present invention relates to a control device and a control method.

  For example, an image forming apparatus such as an MFP (Multifunction Printer) or an LP (Laser Printer) controls driving of each unit by controlling power supply to each load that is each unit of the image forming apparatus. Among the units included in the image forming apparatus, those that perform such control are called information processing systems. There is a technique called Snapshot Boot (Snapshot Boot) for speeding up such an information processing system. This is a snapshot of the state that the boot program is expanded in the main memory. The snapshot is compressed and saved in the nonvolatile memory as appropriate, and when it is restarted, it is expanded directly from the nonvolatile memory to the main memory. This is a technique for shortening the startup time of an information processing system by shortening the processing time related to program development and execution. Further, if this technology is used, the startup time of the information processing system can be shortened even if the processing performance of the CPU (Central Processing Unit) is not high. For example, Patent Document 1 describes that a snapshot is acquired and stored in the nonvolatile memory every time the power of the nonvolatile memory is turned off, that is, every time the nonvolatile memory is shifted to the sleep state.

  However, as in the technique of Patent Document 1, if a snapshot is acquired every time the sleep state is entered, the sleep state may not be entered during the acquisition period, and power consumption may not be reduced.

  The present invention has been made in view of the above, and an object of the present invention is to provide a control device and a control method capable of reducing power consumption required for acquiring a snapshot.

In order to solve the above-described problems and achieve the object, the present invention is a control device that obtains power from a power source and supplies power to a load, and is turned on or off according to a switching operation. Power supply from the power supply to the load by switching off power supply from the power supply to the load and switching it off, and power from the power supply to the load by turning on or off according to a control signal Contact means for switching between supply and interruption, first detection means for detecting on / off of the main power supply switching means, and on / off determination of the contact means according to the detection result of the first detection means And a first control means for outputting the control signal indicating that the contact means is turned on or off according to a determination result of the determination means, and a program for starting up the device is developed. The acquisition unit that acquires the snapshot of the state of the volatile first storage unit obtained according to a predetermined condition, and the snapshot acquired by the acquisition unit at one of the loads A second control unit that stores data in a non-volatile second storage unit; and a measurement unit that measures a value of power supplied from the power supply circuit to the load. The determination unit includes the main power supply switching unit. When the first detection means detects that the contact means is turned off, the contact means is determined to be turned on or off according to the value of the power measured by the measurement means .

The present invention also provides a power supply circuit that obtains power from a power source and supplies power to a load, and is configured to supply power from the power source to the load by being turned on or off in accordance with a switching operation. Main power switching means for switching off the power, contact means for switching power supply from the power source to the load and switching off the power by being turned on or off according to a control signal, and on of the main power switching means Or a first detection means for detecting off, a determination means for determining whether the contact means is turned on or off according to a detection result of the first detection means, and a contact means according to the determination result of the determination means. First control means for outputting the control signal indicating turning on or off, acquisition means, second control means, and measurement means for measuring a value of power supplied to the load by the power supply circuit. Preparation A control method executed by a control device, wherein the acquisition unit uses a snapshot obtained by imaging a state of a volatile first storage unit in which a program for starting the own device is expanded as a predetermined condition. An acquisition step of acquiring in response, and a second control step of causing the second control unit to store the snapshot acquired in the acquisition step in a nonvolatile second storage unit that is one of the loads; When the first detecting unit detects that the main power source switching unit is turned off, the determining unit determines whether the contact unit is turned on or off according to the power value measured by the measuring unit. And a determining step .

  According to the present invention, it is possible to reduce power consumption required to acquire a snapshot.

FIG. 1 is a diagram illustrating the configuration of an image forming apparatus 100 according to the first embodiment. FIG. 2 is an excerpt of the configuration of the sub CPU 104, the relay drive circuit 105, and the first relay contact 106. FIG. 3 is a diagram illustrating the transition to each operation mode of the image forming apparatus 100. FIG. 4 is a diagram illustrating the operable voltage and the operable time in the normal operation mode, the standby mode, and the first power saving mode when the main power switch 107 is turned off. FIG. 5 is a diagram illustrating the operable voltage and the operable time in the second power saving mode when the main power switch 107 is turned off. FIG. 6 is a flowchart showing a procedure of processing performed by the sub CPU 104 when transitioning from the shutdown mode to the standby mode. FIG. 7 is a flowchart showing a procedure of processing for controlling acquisition of a snapshot performed by the main CPU 103. FIG. 8 is a flowchart illustrating a procedure of processing performed by the sub CPU 104 when the main power switch 107 is turned off in each operation mode. FIG. 9 is a diagram illustrating a state in which the voltage of each load with different power consumption decreases with time since the main power switch 107 is turned off. FIG. 10 is an excerpt of the configuration of the sub CPU 104, the relay drive circuit 105, and the first relay contact 106 according to the second embodiment. FIG. 11 is a flowchart illustrating a procedure of processing performed by the sub CPU 104 when transitioning from the shutdown mode to the standby mode. FIG. 12 is a flowchart illustrating a procedure of processing for controlling acquisition of a snapshot performed by the main CPU 103 according to a modification.

  Exemplary embodiments of a control device and a control method according to the present invention will be explained below in detail with reference to the accompanying drawings.

[First embodiment]
First, the configuration of an image forming apparatus having a control device will be described with reference to FIG. The image forming apparatus 100 includes a power supply device 116, a controller 101, an operation panel 111, a data storage unit 112, a FAX (Facsimile) communication unit 113, an image reading unit 114, and an image forming unit 115. Have. Among these devices, devices other than the power supply device 116 are loads that receive power supply from the power supply device 116. Of these, the controller 101 and the data storage unit 112 correspond to an information processing system. The controller 101 includes a main memory 102, a main CPU 103, a sub CPU 104, and a nonvolatile memory 117, and is connected to an external device 120 such as a PC (Personal Computer) via a dedicated line or a network. The network is, for example, a local area network (LAN), an intranet, Ethernet (registered trademark), or the Internet. The power supply device 116 includes a relay drive circuit (Drive circuit) 105, a first relay contact 106, a main power switch (LockerSW) 107, a first AC (Alternate current) / DC (Direct current) power generation unit 108, 2 AC / DC power generation unit 109 and second relay contact 110.

  The main memory 102 is, for example, a ROM (Read Only Memory), a RAM (Random Access Memory), or the like, and stores various data and various programs. In particular, the ROM stores a boot program for starting up the device itself. The data storage unit 112 is a nonvolatile memory such as an HDD (Hard Disk Drive), a NAND flash memory, or NVRAM, and stores various data and various programs. The non-volatile memory 117 is a non-volatile memory such as a NAND flash memory or NVRAM, and stores a snapshot of the RAM state imaged under the control of the main CPU 103 and sub CPU 104, and also acquires a snapshot. A change flag indicating necessity is stored. Such a nonvolatile memory generally has a limit on the number of rewrites. The change flag indicates, for example, that “1 (High)” indicates that it is necessary to acquire a snapshot, and “0 (Low)” that it is not necessary to acquire a snapshot. The main CPU 103 controls the entire image forming apparatus 100 by executing various programs stored in the main memory 102 and the data storage unit 112. At the time of activation, the main CPU 103 expands the boot program stored in the ROM to the RAM, executes the program, and performs activation processing. Then, the main CPU 103 acquires a snapshot obtained by imaging the state of the RAM in which the boot program is expanded according to a predetermined condition, and stores the snapshot in the nonvolatile memory 117. When the main power switch 107 is turned off and then turned on again, the main CPU 103 reads the snapshot stored in the nonvolatile memory 117 and returns it to the RAM. The state of the RAM is restored, and the program is executed from this state to perform a startup process.

  The sub CPU 104 executes various programs stored in the main memory 102 or the data storage unit 112 in place of the main CPU 103 when the main power switch 107 is turned off and power supply to the main CPU 103 is cut off. Thus, the entire image forming apparatus 100 or a part thereof is controlled. Further, the sub CPU 104 acquires a snapshot according to a predetermined condition, and stores the acquired snapshot in the nonvolatile memory 117. The operation panel 111 is formed integrally with a display unit for displaying information and an operation input unit such as a keyboard and a mouse for receiving a user operation input. The FAX communication unit 113 performs FAX communication with an external device (not shown). The image reading unit 114 is a scanner, for example, and reads an image represented on a document. The image forming unit 115 includes, for example, a black and white plotter, a one-drum color plotter, or a four-drum color plotter and an ASIC (Application Specific Integrated Circuit), and includes image data representing an image read by the image reading unit 114 or an external device 120. Various image processing such as error diffusion and gamma conversion is performed on the image data received from the external device, and printing is performed by forming an image on a print medium such as paper using the image data after image processing. .

  The main power switch 107 switches on or off the supply of power from the AC power source 121 by being turned on or off according to the switching operation. The first AC / DC power supply generation unit 108 functions as a PSU (Power Suply Unit), converts an AC voltage (AC power supply) as power supplied from the AC power supply 121 into a DC voltage (DC power supply), and the controller 101. Then, power is supplied to the operation panel 111. The second AC / DC power supply generation unit 109 functions as a PSU, converts the AC voltage supplied from the AC power supply 121 into a DC voltage, a data storage unit 112, a FAX communication unit 113, an image reading unit 114, The power is supplied to the image forming unit 115, and power is supplied to the sub CPU 104 via the second relay contact 110. The relay drive circuit 105 controls on / off of the first relay contact 106 under the control of the sub CPU 104. The first relay contact 106 switches between the supply of electric power from the AC power supply 121 and the interruption thereof under the control of the sub CPU 104 via the relay drive circuit 105. The second relay contact 110 is controlled to be turned on / off under the control of the sub CPU 104.

  FIG. 2 is an excerpt of the configuration of the sub CPU 104, the relay drive circuit 105, and the first relay contact 106. When the main power switch 107 is turned on or off, an ACSW_ON_N signal indicating that is input to the input port of the sub CPU 104. Specifically, when the main power switch 107 is turned on, a High ACSW_ON_N signal is input, and when the main power switch 107 is turned off, a Low ACSW_ON_N signal is input. Further, the sub CPU 104 outputs a REON_DC_N signal that is a control signal for controlling on / off of the first relay contact 106. Specifically, when the first relay contact 106 is turned from OFF to ON, the sub CPU 104 outputs a High REON_DC_N signal indicating that to the relay drive circuit 105, that is, asserts the REON_DC_N signal, When the first relay contact 106 is turned from ON to OFF, a Low REON_DC_N signal indicating that is output from the output port to the relay drive circuit 105, that is, the REON_DC_N signal is deasserted. The relay drive circuit 105 turns off the first relay contact 106 when a Low REON_DC_N signal indicating that the first relay contact 106 is turned off is input. As a result, power is supplied from the AC power source 121 to the controller 101 and the operation panel 111 via the first AC / DC power source generation unit 108, and the data storage unit 112 and the FAX communication unit via the second AC / DC power source generation unit 109. 113, power supply to the image reading unit 114 and the image forming unit 115 is cut off. The relay driving circuit 105 turns on the first relay contact 106 when a Low REON_DC_N signal indicating that the first relay contact 106 is turned on is input. As a result, power is supplied from the AC power source 121 to the controller 101 and the operation panel 111 via the first AC / DC power source generation unit 108, and the second AC / DC power source generation unit is turned on / off according to the ON / OFF state of the second relay contact 110. Power is supplied to the data storage unit 112, the FAX communication unit 113, the image reading unit 114, and the image forming unit 115 via 109. As described above, the first relay contact 106 is turned on or off in accordance with the control signal output from the sub CPU 104, thereby switching the supply of electric power from the AC power source 121 or the interruption thereof.

  Here, control related to acquisition of a snapshot according to the present embodiment will be described. Data related to snapshot acquisition is classified into data that needs to be acquired when its value is changed and data that needs to be acquired when its value is changed. . For this reason, in the present embodiment, the image forming apparatus 100 acquires a snapshot when the value of the former data is changed, and the value of the former data is not changed but only the value of the latter data is changed. Do not take a snapshot if Whether or not to acquire a snapshot accompanying such a change in data value is indicated by the above-described change flag.

  Data whose snapshot needs to be acquired when the value is changed is data in which the value stored in the nonvolatile memory 117 and the value stored in the RAM must always be the same. For example, in the image forming apparatus 100, a setting value (referred to as a user setting value) set by the user via the operation panel 111 during FAX or printing, or a setting value related to the state of the image forming apparatus 100 (referred to as an apparatus state setting value). Etc. This data is used to develop a program in the RAM based on each set value, and affects the development speed. If the set value and the contents of the program developed in the RAM are not consistent, the information stored in the nonvolatile memory 117 is indicated after the information processing system is started once by the snapshot at the next startup. It is necessary to redeploy the program after confirming the consistency with the setting value, and there is a possibility of device malfunction due to a delay in start-up time or a system error. That is, since the snapshot shows the contents of the program expanded in the RAM, when the value of data related to the expansion of the program is changed, that is, when the setting value indicated by the data is changed, It is necessary to take a new snapshot. On the other hand, data whose snapshot is desired to be acquired when the value is changed is, for example, an information processing system such as basic information of an OS (Operating System) or a set value fixedly set in the image forming apparatus 100 In the case where the controller 101 communicates with the external device 120 via the above-described Ethernet (registered trademark), information indicating the link state of the physical layer and the connection partner in the Ethernet (registered trademark) is shown. Etc. For example, when the physical layer in the Ethernet (registered trademark) is activated with a snapshot acquired when the physical layer is in a linked state, the image forming apparatus 100 is not connected to the Ethernet (registered trademark) at the time of activation and is in a linked state. If there is no connection, a connection confirmation process for confirming the connection is required again. However, the time required for the connection confirmation process is very short, and even if the connection confirmation process is executed again, the effect on the startup time of the information processing system is small. For such data, even if the information indicated by the data is changed, there is little effect even if a new snapshot is not acquired, and the previously acquired snapshot can be used instead. .

  In the present embodiment, using such a difference in data properties, a snapshot is acquired and stored in the nonvolatile memory 117 only when the value of data that needs to be acquired is changed. By making it memorize | store, the frequency | count of rewriting to the non-volatile memory 117 can be reduced. In order to classify which data is the data that needs to be acquired when the value is changed, and which data is desired to be acquired when the value is changed. The data classification information is stored in the nonvolatile memory 117, for example. In the data classification information, it can be appropriately changed to which data the data is classified.

  Furthermore, in the present embodiment, after the main power switch 107 is turned on and started, the main CPU 103 performs processing for controlling acquisition of a snapshot. Specifically, the main CPU 103 monitors a change to data that needs to be acquired when the value is changed, and if there is a change, a snapshot that visualizes the state of the RAM at that time. Is stored in the nonvolatile memory 117, and the value of the change flag is rewritten to “0 (Low)”. Note that when the main power switch 107 is turned on to perform the activation process, the main CPU 103 reads the snapshot stored in the nonvolatile memory 117, returns it to the RAM, and performs the activation process. When the main power switch 107 is turned off and the supply of power to the main CPU 103 is cut off, if the value of the change flag is “1 (High)”, the sub CPU 104 acquires the snapshot. Process to control. Specifically, the sub CPU 104 obtains a snapshot obtained by imaging the state of the RAM at that time. Thereafter, the sub CPU 104 stores the snapshot in the nonvolatile memory 117 as data that needs to be saved in the nonvolatile memory 117.

  The image forming apparatus 100 configured as described above makes a transition to one of a plurality of different operation modes, depending on the state of power supplied to each load described above. Transition to each operation mode depends on on / off of the main power switch 107, operation input via the operation panel 111, and a processing state in the image forming unit 115. The operation modes include System Down Process Execution (end process execution mode), Standby Mode (standby mode), Active Mode (normal operation mode), Power Save Mode 1 (first power saving mode), and Power Save Mode 2 (second mode). Power saving mode) and Shutdown Mode (shutdown mode). FIG. 3 is a diagram illustrating the transition to each operation mode of the image forming apparatus 100.

  The end process execution mode shown in the figure is a mode immediately after the main power switch 107 is turned off, and the image forming apparatus 100 performs a safe end process of the information processing system in this mode. As described above, for example, when the supply of power to the data storage unit 112 is suddenly interrupted while data is being transferred to the data storage unit 112 or while the data storage unit 112 is being accessed, Not only is data lost, but the data storage unit 112 itself may be destroyed. In order to avoid such a situation, before the power supply to the data storage unit 112 is interrupted, the sub CPU 104 shifts to an end process execution mode in which a safe end process of the information processing system is performed. The safe end processing of the information processing system means that, for example, data such as image data received from an external device such as the external device 120 is being transferred to be stored in the data storage unit 112, or the image forming unit 115 is If there is data that needs to be saved, such as image data in the middle of processing, the data is stored in the data storage unit 112, or the power supply is interrupted during operation. This is processing for ending access to the data storage unit 112 when access to the data storage unit 112 at risk is being performed. Then, after the execution of the termination process is terminated and the power is safely turned off, the system shifts to a shutdown mode described later (flow E).

  In the normal operation mode, the main power switch 107 is turned on, the first relay contact 106 and the second relay contact 110 are also turned on, and power of a voltage having a predetermined potential is supplied to the information processing system. It is. In this normal operation mode, the main CPU 103 performs processing for controlling the acquisition of the snapshot described above. When the main power switch 107 is turned off while the normal operation mode is set, the sub CPU 104 performs processing for controlling the acquisition of the snapshot described above, and then transitions to the end processing execution mode described above. (Flow A).

  The standby mode is a mode in which, for example, a transition is made when there is no operation input via the operation panel 111 or when no image processing is performed in the image forming unit 115 for a predetermined time or longer. In this standby mode, the main power switch 107 is turned on, the first relay contact 106 and the second relay contact 110 are also turned on, and power of a voltage having a predetermined potential is supplied to the information processing system. The information processing system is in a standby state. After this state, a transition is made to a first power saving mode described next. In the standby mode, the main CPU 103 performs processing for controlling acquisition of the snapshot described above. When the main power switch 107 is turned off in the standby mode, the sub CPU 104 performs the process for controlling the acquisition of the snapshot, and then transitions to the end process execution mode (flow B). .

  In the first power saving mode, the main power switch 107 and the first relay contact 106 are turned on, but the second relay contact 110 is turned off. The power supply to the storage unit 112, the FAX communication unit 113, the image reading unit 114, and the image forming unit 115 is interrupted, and the controller 101 and the operation panel 111 are connected to the controller 101 and the operation panel 111 via the first AC / DC power generation unit 108. The voltage is being supplied. That is, the first power saving mode is a power saving state in which a voltage lower than that in the normal operation mode is supplied. In the first power saving mode, the main CPU 103 performs processing for controlling the acquisition of the snapshot described above. Then, when the main power switch 107 is turned off in the state of the first power saving mode, the sub CPU 104 performs processing for controlling the acquisition of the snapshot described above, and then transitions to the above-described end processing execution mode ( In the flow C), the sub CPU 104 performs the above-described termination processing by the voltage supplied from the AC power supply 121 via the first relay contact 106.

  In the second power saving mode, the main power switch 107 is turned on, but the first relay contact 106 and the second relay contact 110 are turned off, and the image forming apparatus 100 operates in the information processing system. The power supply to the panel 111, the data storage unit 112, the FAX communication unit 113, the image reading unit 114, and the image forming unit 115 is cut off, and only the main memory 102 and the sub CPU 104 of the controller 101 are connected to the first AC / In this state, a voltage is supplied through the DC power generation unit 108. In the second power saving mode, the main CPU 103 performs processing for controlling the acquisition of the snapshot described above. When the main power switch 107 is turned off in the second power saving mode, the sub CPU 104 performs processing for controlling the acquisition of the snapshot described above, and then transitions to the termination processing execution mode described above ( Flow D). At this time, the supply of power to the sub CPU 104 is also cut off, but even after the main power switch 107 is turned off, a time during which the sub CPU 104 can operate (referred to as an operable voltage) can be maintained (referred to as an operable time). ) Can be secured to some extent. Therefore, during this time, the sub CPU 104 can turn on the first relay contact 106 via the relay drive circuit 105. Then, power is supplied to the sub CPU 104 from the first AC / DC power generation unit 108 connected to the first relay contact 106 that is turned on, and the sub CPU 104 can perform the above-described termination processing.

  Here, the operable voltage and the operable time will be described. Conventionally, in the AC power source / DC power source, when the power consumption is large, the voltage at the output terminal is lowered, that is, the charge is quickly discharged. FIG. 4 is a diagram illustrating the operable voltage and the operable time in the normal operation mode, the standby mode, and the first power saving mode when the main power switch 107 is turned off under such characteristics. FIG. 5 is a diagram illustrating the operable voltage and the operable time in the second power saving mode when the main power switch 107 is turned off. The second power saving mode consumes less power than the normal operation mode, the standby mode, and the first power saving mode. For this reason, due to the characteristics of the PSU, the time during which the operable voltage can be maintained after the main power switch 107 is turned off is relatively long. As illustrated in FIGS. 4 to 5, in the normal operation mode, the standby mode, and the first power saving mode, after the main power switch 107 is turned off, the operable time during which the operable voltage can be maintained is about 10 ms. On the other hand, in the second power saving mode with relatively low power consumption, the operable time during which the operable voltage can be maintained is about 1 s. It takes about several tens of ms (referred to as set time) until the first relay contact 106 is actually turned on, but within this 1 s time, the sub CPU 104 passes the first relay contact via the relay drive circuit 105. 106 can be turned on. As described above, in the second power saving mode, the operable voltage is maintained when the main power switch 107 is turned off while reducing the power consumption by turning off the first relay contact 106. In between, the first relay contact 106 can be turned on. For this reason, it is possible to perform safe termination processing of the information processing system, and it is possible to maintain the robustness of the data that needs to be saved and the data storage unit 112.

  The shutdown mode is a mode that transitions when the main power switch 107 is turned off and the execution of the end process is completed in the above-described end process execution mode. The image forming apparatus 100 includes the first relay contact 106 and the second relay contact. 110 is also turned off, and the power supply of the information processing system is cut off. When the main power switch 107 is turned on in this shutdown mode, the state transits to the above-described standby mode (flow F).

  Next, various functions realized by the sub CPU 104 executing various programs stored in the main memory 102 in such a hardware configuration will be described. The sub CPU 104 detects the on / off state of the main power switch 107, and determines the power supplied to each load according to the detection result and the operation input via the operation panel 111 or the processing state in the image forming unit 115. The transition to one of the operation modes having different states is controlled. Then, as described with reference to FIG. 3, when the main power switch 107 is turned on, the sub CPU 104 turns on / off the first relay contact 106 and the second relay contact 110 according to the operation mode. When the main power switch 107 is turned off, the on / off of the first relay contact 106 is controlled as necessary to perform a safe termination process of the information processing system. Specifically, for example, when the main power switch 107 is turned on to shift from the shutdown mode to the standby mode, the sub CPU 104 performs various activation processes. For example, the activation process initializes hardware such as the main memory 102 and the data storage unit 112 of the image forming apparatus 100, and initializes various resources such as various drivers, a scheduler, a timer function, an interrupt function, and a memory management function. Or At this time, the sub CPU 104 determines whether or not the backup function is necessary, that is, whether or not the backup process needs to be performed when the power is cut off during the execution of the startup process. Then, the sub CPU 104 determines ON / OFF of the first relay contact 106 according to the determination result, and outputs a control signal indicating that the first relay contact 106 is turned ON or OFF according to the determination result. By appropriately outputting, the on / off of the first relay contact 106 is controlled to perform various activation processes. The backup process is a process for storing data to be handled during execution of the startup process in the data storage unit 112. In addition, when the main power switch 107 is turned off to shift to the shutdown mode from any one of the normal operation mode, the standby mode, the first power saving mode, and the second power saving mode, the sub CPU 104 causes the above-described snap. A process for controlling the acquisition of shots is performed, and then it is determined whether or not a safe end process of the information processing system is necessary, and on / off of the first relay contact 106 is controlled according to the determination result, The termination process is performed.

  Next, a processing procedure performed by the image forming apparatus 100 according to the present embodiment will be described. First, the procedure of processing performed by the sub CPU 104 when transitioning from the shutdown mode to the standby mode will be described with reference to FIG. If the main power switch 107 is turned on when the main power switch 107 of the image forming apparatus 100 is turned off and in the shutdown mode (step S1), power is supplied to the information processing system. Thus, the sub CPU 104 to which power is supplied cancels the reset of the information processing system and makes the information processing system transition to a usable state (step S2). Then, the sub CPU 104 determines to turn on the first relay contact 106 and asserts the REON_DC_N signal (step S3). The relay drive circuit 105 turns on the first relay contact 106 when the REON_DC_N signal is asserted. Thereafter, the sub CPU 104 performs various activation processes in order to transition to the standby mode. At this time, the sub CPU 104 determines whether or not a backup function is necessary (step S4). If the determination result is affirmative (step S4: YES), the sub CPU 104 decides to turn on the first relay contact 106, and in this case, the first relay contact 106 is kept on and is non-volatile. The snapshot stored in the memory 117 is read out, returned to the RAM, and the activation process is performed (step S5). After the start process ends, the sub CPU 104 determines to turn off the first relay contact 106 and deasserts the REON_DC_N signal (step S6). The relay drive circuit 105 turns off the first relay contact 106 when the REON_DC_N signal is deasserted. Then, it progresses to step S7.

  On the other hand, if the determination result in step S4 is negative (step S4: NO), the sub CPU 104 determines to turn off the first relay contact 106 because it is not necessary to turn on the first relay contact 106. Then, the first relay contact 106 is turned off in the same manner as described above (step S10), the activation process is performed (step S11), and the process proceeds to step S7 after the activation process is completed. In step S7, the sub CPU 104 determines whether or not a backup function is necessary in the next startup process. If the determination result is affirmative (step S7: YES), it is determined to turn on the first relay contact 106, and the first relay contact 106 is turned on in the same manner as described above (step S8). Proceed to S5. On the other hand, when the determination result of step S7 is negative (step S7: NO), the sub CPU 104 determines to turn off the first relay contact 106 because it is not necessary to turn on the first relay contact 106. Then, the first relay contact 106 is kept off and the starting process is performed (step S9). After the starting process is completed, the process proceeds to step S7. The sub CPU 104 repeatedly performs the processes in steps S5 to S9 until execution of various activation processes necessary for transition to the standby mode is completed.

  Next, a procedure of processing for controlling the acquisition of the snapshot performed by the main CPU 103 will be described with reference to FIG. When the information processing system is activated, the main CPU 103 waits for detection of whether or not there is a change to data for which a snapshot needs to be acquired (step S20). Specifically, for example, the main CPU 103 determines whether or not there has been an operation input for changing the above-described user setting value stored in the data storage unit 112 via the operation panel 111, and there is the operation input. (Step S21: YES), the operation input is accepted, and the user setting value is changed according to the operation input. Then, the main CPU 103 determines whether it is necessary to acquire a snapshot in accordance with the change of the user setting value (step S22). For example, the main CPU 103 makes the determination with reference to the data classification information described above. Here, it is assumed that it is determined by the data classification information that a snapshot needs to be acquired in accordance with the change of the user setting value. In this case (step S22: YES), the main CPU 103 rewrites the value of the change flag stored in the nonvolatile memory 117 from “0 (Low)” to “1 (High)” (step S23). Then, the main CPU 103 acquires a snapshot obtained by imaging the state of the RAM at that time and stores it in the nonvolatile memory 117 (step S24). Thereafter, the main CPU 103 rewrites the value of the change flag stored in the nonvolatile memory 117 from “1 (High)” to “0 (Low)” (step S25), and returns to step S20. Even when the determination results of steps S21 and S22 are negative, the process returns to step S20. Thereafter, the main CPU 103 repeats the processes of steps S20 to S25.

  As described above, when power is supplied to the nonvolatile memory 117 that is a snapshot storage destination, that is, the main power switch 107 of the image forming apparatus 100 is turned on, and the operation mode of the image forming apparatus 100 is Is in one of the normal operation mode, standby mode, first power saving mode, and second power saving mode described above, the image forming apparatus 100 acquires a snapshot. Since the power consumed as a device of the image forming apparatus 100 is almost unchanged, this reduces the power consumption compared to the event-driven snapshot acquisition of the entire information processing system as the transition to the power saving state. Can be realized.

  Next, the procedure of processing performed by the sub CPU 104 when the main power switch 107 is turned off in each operation mode described with reference to FIG. 3 will be described with reference to FIG. Among the operation modes, the ACSW_ON_N signal (FIG. 2) input to the sub CPU 104 when the main power switch 107 is turned off in any one of the normal operation mode, the standby mode, the first power saving mode, and the second power saving mode. Change from High to Low. The sub CPU 104 waits for detection whether or not the ACSW_ON_N signal becomes Low. When the sub CPU 104 detects that the ACSW_ON_N signal is Low (step S30: YES), the sub CPU 104 detects whether the first relay contact 106 is on or off (step S31). When the first relay contact 106 is off, the operation mode is the second power saving mode. In this case (step S31: NO), the sub CPU 104 determines to turn on the first relay contact 106 and asserts the REON_DC_N signal (step S32). The relay drive circuit 105 turns on the first relay contact 106 when the REON_DC_N signal is asserted. As a result, power is supplied from the first AC / DC power supply generation unit 108 to the sub CPU 104, and the sub CPU 104 can perform the end process by shifting to the end process execution mode. Thereafter, the process proceeds to step S33. If the first relay contact 106 is turned on in step S31, the process proceeds to step S33.

  In step S <b> 33, the sub CPU 104 refers to the change flag stored in the nonvolatile memory 117 and determines whether it is necessary to acquire a snapshot. When the value of the change flag is “0 (Low) (step S33: YES), the sub CPU 104 determines that the acquisition of the snapshot is unnecessary, and proceeds to step S35. 1 (High) (step S33: NO), here, for example, the case where the main power switch 107 is turned off immediately after step S23 in Fig. 7. In this case, the sub CPU 104 performs the snapshot. It is determined that acquisition is necessary, and a new snapshot obtained by imaging the state of the RAM is acquired and stored in the nonvolatile memory 117 (step S34), and the process proceeds to step S35.

  In step S <b> 35, the sub CPU 104 determines whether there is data that needs to be stored in the data storage unit 112. When there is data that needs to be saved in the data storage unit 112, for example, there is data that needs to be saved in the startup process, or data such as image data received from an external device such as the external device 120 is stored in the data storage unit 112. This is a case where data is being transferred for storage, or there is data that needs to be saved, such as image data being processed by the image forming unit 115. In this case (step S35: YES), the sub CPU 104 waits until the transfer of data that needs to be stored to the data storage unit 112 is completed (step S36), and proceeds to step S37. If the determination result in step S35 is negative, the process proceeds to step S37. In step S37, the sub CPU 104 determines whether or not the data storage unit 112 is being accessed. If the determination result is affirmative (step S37: YES), the sub CPU 104 performs a process of ending access to the data storage unit 112 (step S38). Since the power supply to the information processing system can be safely interrupted after the processing is completed, the sub CPU 104 determines to turn off the first relay contact 106 and deasserts the REON_DC_N signal ( Step S39). The relay drive circuit 105 turns off the first relay contact 106 when the REON_DC_N signal is deasserted. As a result, the supply of power to the information processing system is interrupted, and the image forming apparatus 100 transitions to the shutdown mode. If the determination result in step S37 is negative, the image forming apparatus 100 transitions to the shutdown mode through step S39.

  As described above, according to the operation mode of the image forming apparatus 100, the first relay contact 106 provided to protect the data and the data storage unit 112 from the sudden interruption of the power supply due to the main power switch 107 being turned off. Control on / off of. In particular, in the second power consumption mode, the first relay contact 106 is always turned off, and when the main power switch 107 is turned off, it is turned on to perform a safe termination process of the information system. Accordingly, the power consumption can be reduced by always turning on the first relay contact 106, and when the termination process needs to be performed, the first relay contact is turned on to supply power to the sub CPU 104. be able to. That is, the power consumption can be reduced, and the data that needs to be stored and the robustness of the data storage unit 112 can be maintained. Further, by using the snapshot boot technology, the next start-up of the information processing system can be speeded up, and the number of times of rewriting of the nonvolatile memory 117 which is a nonvolatile memory where the snapshot is stored is reduced. The product life of the nonvolatile memory 117 can be extended. For example, in the technique of Patent Document 1, snapshots are stored in the nonvolatile memory every time the sleep state is entered, and there is a possibility that the product life of the nonvolatile memory may be shortened by tightening the limit on the number of times of rewriting. However, this fear can be avoided in the present embodiment. In addition, when power is supplied to the main CPU 103, the main CPU 103 performs processing for controlling the acquisition of snapshots, thereby acquiring a snapshot in an event-driven manner as the entire information processing system that shifts to a power saving state. In contrast, the power consumption can be reduced.

[Second Embodiment]
Next, a second embodiment of the image forming apparatus will be described. In addition, about the part which is common in the above-mentioned 1st Embodiment, it demonstrates using the same code | symbol or abbreviate | omits description.

  As described with reference to FIGS. 4 to 5 above, the time taken for the voltage to drop after the main power switch 107 is turned off is the controller among the loads when the main power switch 107 is turned off. 101 is proportional to the power consumed by the controller 101, that is, the value of the current consumed by the controller 101 (current consumption value). In addition, the time from when the sub CPU 104 detects that the ACSW_ON_N signal described with reference to FIG. 2 is Low until the REON_DC_N signal is asserted and the set time from when the first relay contact 106 is turned on has elapsed. Although there is some variation depending on the set time of the relay contact used for the first relay contact 106, it is a substantially constant value (referred to as re-ON possible time). Therefore, the current consumption value of the load that can be actually turned on can be derived from the re-ON possible time. This value is called a re-ON possible current value. This corresponds to the value of the operable voltage described above.

  FIG. 9 is a diagram illustrating a state in which the voltage of each load with different power consumption decreases with time since the main power switch 107 is turned off. The load curves a, b, c, d, and e in the figure show the transition of each voltage for a load with large power consumption in that order. In addition, xms in the figure indicates a re-ON possible time. From this figure, regarding the load curves a, b, and c, the voltage applied to the load falls below the operable voltage before the re-ON possible time xms elapses after the main power switch 107 is turned off. Regarding the curves d and e, it can be seen that the voltage applied to the load exceeds the operable voltage from the time when the main power switch 107 is turned off to the time when the re-ON possible time xms elapses. That is, when the load curves d and e are loaded, the first relay contact 106 can be turned on after the main power switch 107 is turned off and before the voltage applied to the load falls below the operable voltage. I understand that. The image forming apparatus 100 controls on / off of the first relay contact 106 using the re-ON possible current value derived from the re-ON possible time corresponding to the operable voltage.

  FIG. 10 is an excerpt of the configuration of the sub CPU 104, the relay drive circuit 105, and the first relay contact 106. In the present embodiment, the image forming apparatus 100 includes an ammeter 118 connected to the output terminal of the first AC / DC power supply generation unit 108 in addition to the configuration illustrated in FIG. The ammeter 118 measures the value of the current supplied as power from the first AC / DC power supply generation unit 108. The sub CPU 104 compares the current value measured by the ammeter 118 as a consumption current value and the re-ON possible current value, and controls on / off of the first relay contact 106 according to the comparison result. . The re-ON possible current value is stored in the main memory 102, for example.

  Next, a procedure of processing performed by the sub CPU 104 when transitioning from the shutdown mode to the standby mode will be described with reference to FIG. The processes in steps S1 to S3 and S20 to S22 are the same as those in the first embodiment described above. If the sub CPU 104 determines in step S22 that a snapshot needs to be acquired (step S22: YES), in step S50, the sub CPU 104 determines whether the first relay contact 106 is on. When the sub CPU 104 determines that the first relay contact 106 is off (step S50: NO), in step S51, the first relay contact 106 is turned on similarly to step S8 described above, and the process proceeds to step S52. When the sub CPU 104 determines that the first relay contact 106 is on (step S50: YES), the sub CPU 104 proceeds to step S52. In step S <b> 52, the sub CPU 104 causes the main CPU 103 to acquire a snapshot obtained by imaging the state of the RAM at that time and store the snapshot in the nonvolatile memory 117. Thereafter, the main CPU 103 rewrites the value of the change flag stored in the nonvolatile memory 117 from “1 (High)” to “0 (Low)” (step S53), and returns to step S20.

  On the other hand, if it is determined in step S22 that snapshot acquisition is unnecessary (step S22: NO), in step S54, the sub CPU 104 determines that the current consumption value measured by the ammeter 118 is greater than the re-ON possible current value. Determine whether or not. If the determination result is negative (step S54: NO), the sub CPU 104 determines to turn off the first relay contact 106. In step S55, the first relay contact 106 is the same as step S10 described above. Turn off. Then, it returns to step S20. If the determination result in step S54 is affirmative (step S54: YES), in step S56, the sub CPU 104 determines to turn on the first relay contact 106, and whether the first relay contact 106 is off. Judge whether or not. When it is determined that the first relay contact 106 is on (step S56: NO), the process returns to step S20. When it is determined that the first relay contact 106 is off (step S56: YES), the sub CPU 104 turns on the first relay contact 106 in the same manner as in the above-described step S8 in step S57, and then proceeds to step S20. Return. The sub CPU 104 repeats the processes in steps S20 to S22 and S50 to S57 as described above.

  As described above, the power consumption can be effectively reduced by dynamically controlling on / off of the first relay contact 106 according to the current consumption value in the controller 101. In addition, by using the snapshot, it is possible to speed up the next activation of the information processing system and reduce the number of times the nonvolatile memory 117 to which the snapshot is stored is rewritten, thereby reducing the product life of the nonvolatile memory 117. Can be extended. In addition, when power is supplied to the main CPU 103, the main CPU 103 performs processing for controlling the acquisition of snapshots, thereby acquiring a snapshot in an event-driven manner as the entire information processing system that shifts to a power saving state. In contrast, the power consumption can be reduced.

[Modification]
Note that the present invention is not limited to the above-described embodiment as it is, and can be embodied by modifying the constituent elements without departing from the scope of the invention in the implementation stage. Moreover, various inventions can be formed by appropriately combining a plurality of constituent elements disclosed in the embodiment. For example, some components may be deleted from all the components shown in the embodiment. Furthermore, constituent elements over different embodiments may be appropriately combined. Further, various modifications as exemplified below are possible.

  In each of the embodiments described above, various programs executed by the main CPU 103 may be stored on a computer connected to a network such as the Internet and provided by being downloaded via the network. The various programs are recorded in a computer-readable recording medium such as a CD-ROM, a flexible disk (FD), a CD-R, and a DVD (Digital Versatile Disk) in a file in an installable or executable format. The computer program product may be provided. The same applies to various programs executed by the sub CPU 104.

  In each of the embodiments described above, the image forming apparatus 100 is not limited to the one described above, and may have at least one of a copy function, a printer function, a scanner function, and a facsimile function. That is, the image forming apparatus 100 may include at least one of a part relating to a copy function and a part relating to a printer function of the image forming unit 115, an image reading unit 114, and a FAX communication unit 113. Further, the information processing apparatus is not limited to the image forming apparatus 100 but may be a personal computer, a portable information terminal, or the like.

  In the first embodiment described above, in step S35 in FIG. 8, the sub CPU 104 determines whether or not the data storage unit 112 is being accessed, and the determination result is affirmative. In the case where the first relay contact 106 is on, the access end processing is performed. However, even when the data storage unit 112 is being accessed, if only reading data from the data storage unit 112 is performed, the sub CPU 104 does not perform the process of ending the access. In addition, the first relay contact 106 may be turned off.

  In each of the above-described embodiments, the change flag is stored in the nonvolatile memory 117. However, the present invention is not limited to this, and for example, the change flag may be stored in a register included in the sub CPU 104 or the image forming apparatus 100. Alternatively, a battery backup circuit may be separately provided and stored in the battery backup circuit.

  In each of the above-described embodiments, in the processing for controlling the acquisition of the snapshot performed by the main CPU 103 when the information processing system is started, the snapshot is acquired again after an arbitrary set time from the last acquisition. Also good. As described above, data related to snapshot acquisition includes data that needs to be acquired when its value is changed, and data that is desired to acquire snapshot when its value is changed. However, it is functionally desirable that both of them are stored in the latest state, that is, the state immediately before the information processing system is turned off. For this reason, the latest state can be maintained by periodically acquiring and updating snapshots. In this case, the image forming apparatus 100 includes a timer for timing, and the main CPU 103 sets the first set time and the second set time related to the acquisition of the snapshot in each timer, and the elapse of the time set in the timer Accordingly, a snapshot is acquired and stored in the nonvolatile memory 117, and the value of the change flag is rewritten. The first setting time and the second setting time are arbitrarily set times. For example, the first setting time and the second setting time are set by a user operation input via the operation panel 111, and these values are stored in the nonvolatile memory 117, for example. In this case, the nonvolatile memory 117 is desirably a magnetic recording device such as a hard disk device or an MRAM that has no limit on the number of rewrites. FIG. 12 is a flowchart showing a procedure of processing for controlling acquisition of a snapshot performed by the main CPU 103 according to the present modification. Steps S1 and S2 are the same as those in the first embodiment. In step S70, the main CPU 103 sets the first set time in the timer, and starts measuring the first set time. Then, when the main CPU 103 determines that the first set time has elapsed due to the timing of the timer (step S71: YES), the main CPU 103 acquires a snapshot that visualizes the state of the RAM and acquires the nonvolatile memory 117. (Step S72). Then, the main CPU 103 rewrites the value of the change flag from “1 (High)” to “0 (Low)” (step S73).

  Thereafter, the main CPU 103 sets the second set time in the timer and starts measuring the second set time (step S74). Until the second set time elapses, it can be said that the snapshot acquired in step S72 is in the latest state. When the main power switch 107 is turned off in this state, the value of the change flag is “0 (Low)”, so that the determination result of step S33 in FIG. It will not be acquired. When the main CPU 103 determines that the second set time has elapsed due to the timing of the timer (step S75: YES), the main CPU 103 changes the value of the change flag from “0 (Low)” to “1 (High)”. "(Step S76). When the main power switch 107 is turned off in this state, since the value of the change flag is “1 (High)”, the determination result in Step S33 of FIG. 8 is negative, and the sub CPU 104 determines in Step S34. A snapshot is acquired and stored in the nonvolatile memory 117. After step S76, the process returns to step S70, and thereafter, the main CPU 103 repeats the processes of steps S70 to S76.

  According to the configuration as described above, when the value is changed, it is not always necessary to acquire the snapshot, and the data that is desired to be acquired may be changed at a relatively short time interval. Since it can be acquired, the latest snapshot can always be stored in the non-volatile memory 117, and the speed at the next startup can be increased. At the same time, it is possible to increase the probability that the snapshot does not have to be acquired every time the main power switch 107 is turned off, and the image forming apparatus 100 can be quickly turned off. Compared with the case of acquiring a snapshot, the power consumption of the information processing system can be reduced. Further, according to such a configuration, since complicated setting changes are not required, the convenience of user settings can be improved.

  In each embodiment and each modification described above, when the information processing system is activated, the main CPU 103 performs the process of controlling the acquisition of the snapshot illustrated in FIG. 5, but is not limited thereto. The sub CPU 104 may perform the process.

100 Image forming apparatus 101 Controller 102 Main memory 103 Main CPU
104 Sub CPU
105 relay drive circuit 106 first relay contact 107 main power switch 108 first AC / DC power generation unit 109 second AC / DC power generation unit 110 second relay contact 111 operation panel 112 data storage unit 113 FAX communication unit 114 image reading unit 115 Image forming unit 116 Power supply device 118 Ammeter 120 External device 121 AC power supply

JP 2009-187134 A

Claims (11)

A power supply circuit that obtains power from the power supply and supplies power to the load;
A main power source switching means for switching between supply and interruption of power from the power source to the load by being turned on or off according to a switching operation;
Contact means for switching between supply and interruption of power from the power source to the load by being turned on or off according to a control signal;
First detection means for detecting on or off of the main power supply switching means;
Determining means for determining whether the contact means is on or off according to the detection result of the first detecting means;
First control means for outputting the control signal indicating turning on or off the contact means according to a determination result of the determination means;
An acquisition unit that acquires, according to a predetermined condition, a snapshot obtained by imaging the state of the volatile first storage unit in which a program for starting the own device is expanded;
Second control means for storing the snapshot acquired by the acquisition means in a nonvolatile second storage means that is one of the loads ;
Measuring means for measuring the value of power supplied to the load by the power supply circuit;
With
The determining means determines whether the contact means is turned on or off according to the power value measured by the measuring means when the first detecting means detects that the main power supply switching means is turned off. <br/> A control device characterized by the above.   The determining means is obtained in advance according to the power value measured by the measuring means and the characteristics of the power supply when the first detecting means detects that the main power supply switching means is turned off, and It compares with the value of electric power for enabling the contact means to be turned on, and determines whether the contact means is turned on or off according to the comparison result.
The control device according to claim 1. Said acquisition means, if the value of the first data acquisition required snapshot is changed if the value has changed, in claim 1 or 2, characterized in that to obtain the snapshot The control device described. The control apparatus according to claim 3 , further comprising a third storage unit that stores a flag indicating whether the snapshot needs to be acquired. And a third control means for rewriting the flag stored in the third storage means to indicate that the snapshot needs to be acquired when the value of the first data is changed. The control device according to claim 4 . It further comprises operation input receiving means for receiving a user's operation input,
When the operation input accepting unit accepts an operation input for changing the value of the first data, the third control unit stores in the third storage unit so as to indicate that the snapshot needs to be acquired. The control device according to claim 5 , wherein the stored flag is rewritten. The acquisition unit acquires the snapshot when the first detection unit detects that the main power supply switching unit is turned off and the flag indicates that the snapshot needs to be acquired. When the first detection unit detects that the main power supply switching unit is turned off and when the flag indicates that the snapshot acquisition is unnecessary, the snapshot is not acquired. The control device according to any one of claims 4 to 6 , characterized in that: It further comprises a timing means for timing,
The control device according to any one of claims 1 to 7 , wherein the acquisition unit acquires the snapshot every time when the time measured by the timing unit elapses a set time. The load includes non-volatile fourth storage means for storing data,
When the first detection unit detects that the main power supply switching unit is turned off and the access to the fourth storage unit is being performed, the determination unit continues until the access ends. control device according to any one of claims 1 to 8, characterized in that to determine the turning on contact means. The load includes non-volatile fourth storage means for storing data,
When the first detecting means detects that the main power supply switching means is turned off, the determining means is accessing the fourth storage means and the data from the fourth storage means If reading a control device according to any one of claims 1 to 9, characterized in that decides to turn off the contact means. A power supply circuit that obtains power from the power supply and supplies power to the load, and a main power supply that switches on and off the supply of power from the power supply to the load by being turned on or off according to a switching operation A switching means, a contact means for switching power supply from the power source to the load and its interruption by being turned on or off according to a control signal, and a first detecting the on or off of the main power supply switching means. 1 detecting means, determining means for determining whether the contact means is turned on or off according to the detection result of the first detecting means, and turning the contact means on or off according to the determination result of the determining means executed by the control apparatus comprising: a first control means for outputting the control signal, an acquiring unit, a second control means, and a measuring means for the power supply circuit to measure the value of the power supplied to the load indicating that A control method,
An acquisition step in which the acquisition unit acquires a snapshot obtained by imaging the state of the volatile first storage unit in which a program for starting up the device is developed according to a predetermined condition;
A second control step in which the second control unit stores the snapshot acquired in the acquisition step in a nonvolatile second storage unit that is one of the loads ;
When the first detecting means detects that the main power supply switching means is turned off, the determining means determines whether the contact means is turned on or off according to the power value measured by the measuring means. And a determination step .

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