JP2017204106A - Image forming apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an image forming apparatus that can achieve both improvement of execution efficiency during operation and a reduction in power consumption in a standby state.SOLUTION: An image forming apparatus comprises a control part 11 that includes a multi-core CPU 111 including a plurality of cores and can simultaneously control a plurality of predetermined operations achieved by executing independent programs. The control part 11 includes a switching part (control part 11) that switches between an AMP configuration allocating the predetermined operation individually to each of the plurality of cores and an SMP configuration using the plurality of cores in combination to execute one or more predetermined operations. The switching part switches to the AMP configuration while waiting for the predetermined operations and switches to the SMP configuration during the predetermined operations.SELECTED DRAWING: Figure 1

Description

  The present invention relates to an image forming apparatus.

  In recent years, CPUs that execute firmware have become multi-core, and with regard to job processing and device management, it has become possible to simultaneously execute a plurality of parallel or independent processes using a plurality of cores. In general, the former parallel processing is called SMP (Symmetric Multiprocessing), and the latter independent processing is called AMP (Asymmetric Multiprocessing). In SMP, individual cores share memory equally and share processing, whereas in AMP, memory is allocated to each individual core and independent processing is executed (separate OS and programs are executed). It becomes a feature.

  Conventionally, an MFP (Multi-Function Peripheral), which is a multi-function machine having a plurality of functions such as copying, faxing, printing, etc., for screen display, COPY / SCAN / PRINT control, In general, a plurality of independent programs for control, FAX communication control, and the like are executed by individual CPUs. On the other hand, as the CPU becomes multi-core, a SoC that integrates a single multi-core CPU having a plurality of cores or a peripheral application specific integrated circuit (ASIC) for functions that have been realized by using a plurality of CPUs in the past. (System on a Chip) can be realized, and CPUs are integrated and abolished for the purpose of cost reduction.

  In general, when firmware executed by a plurality of CPUs and OSs is executed by a single multi-core CPU or SoC, each of a plurality of cores and a plurality of conventional CPUs (OS) are in a one-to-one relationship. A highly portable AMP configuration that can be replaced is advantageous. In terms of power consumption during standby, an AMP configuration that can easily cut power supply independently for each core is advantageous. On the other hand, with respect to the execution efficiency of the entire CPU, there are many cores that can be used for one or a plurality of processes (that is, a plurality of cores can be used for one or a plurality of processes). The SMP configuration is particularly advantageous in parallel processing.

As an example to which the AMP configuration is applied, a technology for ensuring real-time performance by suppressing delay of processing that requires real-time property (real-time processing) is disclosed (for example, see Patent Document 1).
In addition, as another example to which the AMP configuration is applied, a technique that enables rapid execution of real-time processing is disclosed (for example, see Patent Document 2).

JP 2010-226283 A JP 2007-193744 A

  However, there is a problem that execution efficiency is inferior to the SMP configuration when the CPU is integrated and the AMP configuration is selected with emphasis on portability, standby power consumption, and real-time performance. Further, in order to obtain a processing speed equivalent to that of the SMP configuration in the AMP configuration, it is necessary to select a higher-performance CPU, which increases the cost, and there is a problem that a contradiction arises with the purpose of CPU consolidation.

  SUMMARY OF THE INVENTION An object of the present invention is to provide an image forming apparatus capable of achieving both improvement in execution efficiency during operation and reduction in standby power consumption.

The invention described in claim 1 has been made to achieve the above object,
In an image forming apparatus including a multi-core CPU having a plurality of cores and including a control unit capable of simultaneously controlling a plurality of predetermined operations realized by executing independent programs.
The control unit includes a switching unit that switches between an AMP configuration in which the predetermined operation is individually assigned to each of the plurality of cores and an SMP configuration in which the plurality of cores are used in combination to execute one or a plurality of the predetermined operations. Prepared,
The switching unit switches to the AMP configuration during standby of the predetermined operation and switches to the SMP configuration during the predetermined operation.

According to a second aspect of the present invention, in the image forming apparatus according to the first aspect,
The switching unit is a case where a plurality of the predetermined operations are performed in the SMP configuration, and the predetermined operation is performed when there is a predetermined processing period for performing a predetermined process that requires real-time property in the predetermined operations performed. The processing period is switched to the AMP configuration.

According to a third aspect of the present invention, in the image forming apparatus according to the second aspect,
When one of a plurality of predetermined operations performed in the SMP configuration is FAX communication, the switching unit switches to the AMP configuration during a period during an incoming call process and a period during a capability exchange process with a partner device. And

According to a fourth aspect of the present invention, in the image forming apparatus according to any one of the first to third aspects,
When the predetermined operation is fax communication, the switching unit switches to the AMP configuration when waiting for an incoming fax, and switches to the SMP configuration during the fax communication.

  According to the present invention, it is possible to achieve both improvement in execution efficiency during operation and reduction in standby power consumption.

FIG. 3 is a functional block diagram illustrating a control structure of the image forming apparatus according to the present embodiment. 5 is a flowchart showing an operation of the image forming apparatus according to the present embodiment. It is a figure which shows an example of the predetermined | prescribed process and predetermined | prescribed process period when one of the some predetermined operations started is FAX communication. It is a time chart which shows the specific process of a control part when FAX communication is started at the time of operation | movement standby. It is a time chart which shows the specific process of a control part when FAX communication is started during copying operation.

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

The image forming apparatus 10 according to the present embodiment is an MFP having functions such as copying, FAX, and printing installed in a company or office, and can execute a plurality of types of jobs.
As shown in FIG. 1, the image forming apparatus 10 includes a control unit 11, an operation unit 12, a display unit 13, an image reading unit 14, an image forming unit 15, a communication unit 16, a storage unit 17, It is configured with.

The control unit 11 includes a multi-core CPU 111 having two cores (core X and core Y) and a RAM 112, and comprehensively controls processing operations of each unit of the image forming apparatus 10. The multi-core CPU 111 reads out various programs stored in the storage unit 17, develops them in the RAM 112, and executes various processes in cooperation with the programs. Note that the number of cores of the multi-core CPU 111 is not limited to two and may be three or more.
In the present embodiment, the control unit 11 has an SMP configuration in which individual cores included in the multi-core CPU 111 share the memory (RAM 112) equally and shares the processing, and an independent memory (RAM 112) is allocated to each individual core. An AMP configuration for executing processing can be freely switched. That is, the control unit 11 functions as a switching unit of the present invention.

  The operation unit 12 includes various operation keys such as a numeric keypad and a start key, receives a key operation by the user, and outputs an operation signal to the control unit 11. The operation unit 12 has a pressure-sensitive (resistance film pressure type) touch panel in which transparent electrodes are arranged in a grid pattern so as to cover the upper surface of the display screen of the display unit 13, and the power point pressed by a finger or a touch pen is used. The XY coordinates are detected by voltage values, and the detected position signal is output to the control unit 11 as an operation signal. Note that the touch panel is not limited to a pressure-sensitive type, and may be another electrostatic type, an optical type, or the like.

  The display unit 13 is configured by an LCD (Liquid Crystal Display) or the like, and displays various operation buttons, device status display, operation status of each function, and the like on the display screen according to instructions of a display signal input from the control unit 11. I do.

  The image reading unit 14 includes a light source, a CCD (Charge Coupled Device) image sensor, an A / D converter, and the like. The reflected image of the light scanned from the light source to the document is imaged and photoelectrically converted to convert the document. The image is read, the read image is A / D converted, and the obtained image data is output to the control unit 11.

  The image forming unit 15 electronically prints paper supplied from the paper feed tray on the basis of a print job transmitted from an external device, image data output from the image reading unit 14, FAX data received by the communication unit 16, and the like. Perform photographic image formation. The image forming unit 15 includes a photosensitive drum, a charging unit that charges the photosensitive drum, an exposure unit that exposes and scans the surface of the photosensitive drum based on image data, and forms an electrostatic latent image. The image forming apparatus includes a developing unit that attaches toner to the electrostatic latent image, a transfer unit that transfers the toner image formed on the photosensitive drum to a sheet, and a fixing unit that fixes the toner image formed on the sheet. The image forming method by the image forming unit 15 is not limited to the electrophotographic method, and any well-known method such as an ink jet method or a thermal transfer method can be employed.

  The communication unit 16 includes a network interface and the like, and transmits and receives data to and from an external device connected via a communication network. For example, the communication unit 16 receives a print job transmitted from an external device. The communication unit 16 is connected to a public line, and transmits and receives FAX data.

  The storage unit 17 is configured by a nonvolatile semiconductor memory, HDD (Hard Disc Drive), or the like, and executes a system program that can be executed by the image forming apparatus 10, various processing programs that can be executed by the system program, and these various processing programs. The data used at the time of processing, the data of the processing result calculated by the control unit 11, and the like are stored.

  Next, the operation of the image forming apparatus 10 according to the present embodiment will be described with reference to the flowchart of FIG. This process is started when the image forming apparatus 10 is in an idle (IDLE) state after the image forming apparatus 10 is turned on.

  First, the control unit 11 switches to the AMP configuration, and turns off the power of a core (hereinafter referred to as a non-operating core) that does not need to be assigned a process when waiting for operation (step S101). That is, the control unit 11 assigns the processing during standby to one core and turns off the power to the remaining non-operating cores. As a result, power consumption during operation standby can be reduced.

Next, the control unit 11 determines whether or not a predetermined operation has been started (step S102). The predetermined operation is an operation (function) realized by executing an independent program. Examples of the predetermined operation include copying, FAX, and printing.
When it is determined that the predetermined operation has been started (step S102: YES), the control unit 11 proceeds to the next step S103.
On the other hand, when it is determined that the predetermined operation has not been started (step S102: NO), the control unit 11 repeats the process of step S102 until the predetermined operation is started.

  Next, the control unit 11 switches to the SMP configuration and performs the processing by sharing the started predetermined operation among all the cores included in the multi-core CPU 111 (step S103). Thereby, the execution efficiency of the predetermined operation can be improved.

Next, the control unit 11 determines whether another predetermined operation has been started (step S104). That is, the control unit 11 determines whether it is necessary to perform a plurality of predetermined operations simultaneously after the process of step S104.
When it is determined that another predetermined operation has been started (step S104: YES), the control unit 11 proceeds to the next step S105.
On the other hand, when it determines with the control part 11 not having started other predetermined operation | movement (step S104: NO), it transfers to step S110.

Next, the control unit 11 determines whether or not there is a processing period (predetermined processing period) for performing a process (predetermined process) that requires real-time characteristics in a plurality of started predetermined operations (Step S11). S105). FIG. 3 shows an example of the predetermined processing and the predetermined processing period when one of the started predetermined operations is FAX communication. The FAX communication is composed of five phases (processing) A to E as shown in FIG. Phase A is an incoming call process. Phase B is a capability exchange process with the counterpart device. Phase C is image data transmission / reception processing. Phase D is data confirmation processing. Phase E is line disconnection processing. Of the five phases A to E, phase A (incoming processing) and phase B (capability exchange processing with the partner machine) are processing (predetermined processing) that requires real-time processing, so the periods of phase A and phase B are The predetermined processing period H1 is reached.
When it is determined that the predetermined processing period exists (step S105: YES), the control unit 11 proceeds to step S107.
On the other hand, when it is determined that the predetermined processing period does not exist (step S105: NO), the control unit 11 proceeds to the next step S106.

  In step S <b> 106, the control unit 11 performs processing by sharing the started predetermined operations among all the cores included in the multi-core CPU 111 (step S <b> 106), and proceeds to step S <b> 110. Thereby, even if it is a case where several predetermined operation | movement is performed, execution efficiency can be improved.

  In step S107, the control unit 11 switches to the AMP configuration at the timing when the predetermined process is started, assigns the predetermined process with priority to one core, and assigns a predetermined operation not including the predetermined process to the remaining cores (step S107). S107). As a result, the predetermined process can be reliably executed, so that real-time performance can be ensured even when a plurality of predetermined operations are performed simultaneously.

Next, the control unit 11 determines whether or not the predetermined process has been completed (step S108).
When it is determined that the predetermined process has been completed (step S108: YES), the control unit 11 proceeds to the next step S109.
On the other hand, when it is determined that the predetermined process has not ended (step S108: NO), the control unit 11 repeats the process of step S108 until the predetermined process ends.

  Next, the control unit 11 switches to the SMP configuration and performs processing by sharing the started predetermined operations among all the cores included in the multi-core CPU 111 (step S109), and proceeds to the next step S110.

In step S110, the control unit 11 determines whether or not all the predetermined operations that have been started have been completed (step S110).
When it is determined that all the predetermined operations have been completed (step S110: YES), the control unit 11 proceeds to the next step S111.
On the other hand, when it is determined that all the predetermined operations have not been completed (step S110: NO), the control unit 11 proceeds to step S104 and repeats the processes after step S104.

  Next, the control unit 11 switches to the AMP configuration and turns off the power of the non-operating core (step S111).

Next, the control unit 11 determines whether or not an operation for turning off the power of the image forming apparatus 10 has been performed (step S112).
When it is determined that an operation to turn off the power of the image forming apparatus 10 has been performed (step S112: YES), the control unit 11 ends the process and turns off the power of the image forming apparatus 10.
On the other hand, if the control unit 11 determines that an operation to turn off the power of the image forming apparatus 10 has not been performed (step S112: NO), the control unit 11 proceeds to step S102 and repeats the processing after step S102.

  FIG. 4 shows an example of a time chart showing specific processing of the control unit 11 (multi-core CPU 111) when FAX communication is started during operation standby.

  At the time of operation standby, the control unit 11 switches to the AMP configuration as control of the operation standby period T11, assigns the operation standby processing to the core X of the two cores included in the multi-core CPU 111, and is in an idle state (waiting for an incoming call). And the power of the remaining core Y is turned off (OFF).

  When the FAX communication is started, the control unit 11 switches to the SMP configuration as the control of the period T12 during the FAX communication, and performs control related to the started FAX communication (FAX communication control) for all the cores included in the multi-core CPU 111. (Core X and Core Y) share the processing.

  When the FAX communication is completed, the control unit 11 switches to the AMP configuration as the control of the operation waiting period T13, assigns the operation standby processing to the core X to be in an idle state, and sets the remaining core Y. Turn off the power.

  As described above, in the example shown in FIG. 4, the power consumption during operation standby can be suppressed by switching to the AMP configuration at the time of FAX non-communication, and the execution efficiency is improved by switching to the SMP configuration at the time of FAX communication. be able to.

  In the example shown in FIG. 4, the operation standby processing is assigned to the core X in the control of the operation standby periods T <b> 11 and T <b> 13, but is not limited to this. That is, the standby process may be assigned to the core Y, and the power of the core X may be turned off.

  FIG. 5 shows an example of a time chart showing specific processing of the control unit 11 (multi-core CPU 111) when FAX communication is started during a copy (COPY) operation. In the example shown in FIG. 5, a case will be described in which there is a processing period (predetermined processing period) for performing processing (predetermined processing) that requires real-time processing for FAX communication.

  When the copy operation is started, the control unit 11 switches to the SMP configuration as control of the period T21 during the copy operation, and controls all the cores (core X and cores) included in the multi-core CPU 111 to perform control related to the started copy operation. Y) share the processing.

  When the FAX communication is started during the copy operation, the control unit 11 controls the period T22 during the combined operation of the copy operation and the FAX communication. In the example illustrated in FIG. 5, the period T22 during the combined operation includes three periods T23 to T25. The first period T23 is a period until a predetermined process of FAX communication is started. The second period T24 is a period during which a predetermined process of FAX communication is performed (predetermined processing period). The third period T25 is a period in which the predetermined process of FAX communication is finished and the predetermined process is not performed.

Specifically, in the first period T23 until the predetermined process is started, the control unit 11 performs control related to the copy operation and FAX communication for all the cores (core X and core Y) included in the multi-core CPU 111. Share and process.
In the second period T24 in which the predetermined process is performed, the control unit 11 switches to the AMP configuration at a timing at which the predetermined process is started, assigns the predetermined process of FAX communication with priority to one core Y, and the remaining cores A predetermined operation (copy operation) not including a predetermined process is assigned to X.
In the third period T25 when the predetermined process is completed, the control unit 11 switches to the SMP configuration, and, similarly to the first period T23, controls related to the copy operation and the FAX communication are performed on all the cores (core X And the core Y).

  When the FAX communication is completed in the combined operation, the control unit 11 switches to the SMP configuration as the control of the period T26 during the copy operation, and controls all the cores (core X and core Y) included in the multi-core CPU 111 to control the copy operation. ) To share the process.

  When the copy operation is completed, the control unit 11 switches to the AMP configuration as the control of the operation waiting period T27, assigns the operation waiting process to the core X and sets the idle state, and sets the remaining core Y. Turn off the power.

  As described above, in the example shown in FIG. 5, when FAX communication is performed in parallel with the copy operation, the processing load of each operation is predicted in advance, and processing that requires real-time properties (predetermined processing) is performed. In the processing period (predetermined processing period), real-time performance can be ensured by switching to the AMP configuration.

  In the example shown in FIG. 5, in the control of the second period T24 in which the predetermined process of FAX communication is performed during the combined operation, the predetermined process of FAX communication is preferentially assigned to one core Y. However, the present invention is not limited to this. That is, a predetermined process of FAX communication may be assigned with priority to the core X, and a predetermined operation (copy operation) that does not include the predetermined process may be assigned to the core Y. Further, in the control of the operation waiting period T27, the operation waiting process is assigned to the core X. However, the present invention is not limited to this, and the waiting process is assigned to the core Y. The power source of X may be turned off.

As described above, the image forming apparatus 10 according to the present embodiment has the multi-core CPU 111 having a plurality of cores, and can simultaneously control a plurality of predetermined operations realized by executing independent programs. A control unit 11 is provided. The control unit 11 is a switching unit (control unit) that switches between an AMP configuration in which a predetermined operation is individually assigned to each of a plurality of cores and an SMP configuration in which a plurality of cores are used together to execute one or a plurality of predetermined operations. 11). The switching unit switches to the AMP configuration while waiting for a predetermined operation, and switches to the SMP configuration during the predetermined operation.
Therefore, according to the image forming apparatus 10 according to the present embodiment, since the predetermined operation started can be shared by all the cores included in the multi-core CPU 111, the execution efficiency of the predetermined operation can be improved. it can. In addition, since it is possible to perform processing for assigning processing during operation standby to one core and powering off the remaining non-operation cores, power consumption during operation standby can be reduced. Therefore, it is possible to achieve both improvement in execution efficiency during operation and reduction in standby power consumption.

In addition, according to the image forming apparatus 10 according to the present embodiment, the switching unit performs a predetermined process that requires real-time characteristics in the predetermined operation that is performed when a plurality of predetermined operations are performed in the SMP configuration. When the predetermined processing period exists, the predetermined processing period is switched to the AMP configuration.
Therefore, according to the image forming apparatus 10 according to the present embodiment, a predetermined process requiring real-time property can be reliably executed by preferentially allocating to one core, and thus a plurality of predetermined operations are performed simultaneously. Even in this case, real-time performance can be ensured while ensuring execution efficiency during operation.

Further, according to the image forming apparatus 10 according to the present embodiment, when one of a plurality of predetermined operations performed in the SMP configuration is FAX communication, the switching unit exchanges the period during the incoming call processing and the capability exchange with the partner machine. The period during processing is switched to the AMP configuration.
Therefore, according to the image forming apparatus 10 according to the present embodiment, particularly in FAX communication in which relay switching processing and modem control frequently occur and processing that requires real-time performance and processing that does not require real-time performance are mixed. However, since a predetermined process that requires real-time performance can be reliably executed, it is possible to suppress a communication speed delay and a communication error.

In addition, according to the image forming apparatus 10 according to the present embodiment, when the predetermined operation is FAX communication, the switching unit switches to the AMP configuration when waiting for a FAX incoming call and switches to the SMP configuration during FAX communication.
Therefore, according to the image forming apparatus 10 according to the present embodiment, since the started FAX communication can be shared by all the cores included in the multi-core CPU 111, the execution efficiency of the predetermined operation can be improved. it can. In addition, since it is possible to perform processing for assigning the processing in the waiting state for FAX incoming call to one core and turning off the power of the remaining non-operating cores, it is possible to reduce the power consumption in the incoming waiting state for FAX. it can. Therefore, even in FAX communication in which control related to communication is relatively complicated, it is possible to achieve both improvement in execution efficiency during operation and reduction in standby power consumption.

  As mentioned above, although concretely demonstrated based on embodiment which concerns on this invention, this invention is not limited to the said embodiment, It can change in the range which does not deviate from the summary.

  For example, in the above-described embodiment, in the processing from step S104 to step S109 in FIG. 2, when a plurality of predetermined operations are performed at the same time, the control to switch to the AMP configuration is performed during the predetermined processing period. Is not to be done. That is, the processing in steps S104 to S109 may not be performed. In that case, after the processing in step S103, when all the predetermined operations that have been started have been completed, switching to the AMP configuration will result in consumption during operation standby. Electric power can be reduced.

  Further, in the above-described embodiment, the predetermined processing period is exemplified by the period during the FAX communication incoming process and the period during the capability exchange process with the partner machine, but is not limited thereto. The predetermined processing period may be any period as long as it is a period for performing processing that requires real-time characteristics.

  In the above-described embodiment, the period of waiting for operation is described by way of example in a state waiting for an incoming fax communication. However, the present invention is not limited to this. For example, it may be in a standby state (waiting for instructions) of a copy operation or a print operation.

In addition, regarding the detailed configuration of each apparatus constituting the image forming apparatus and the detailed operation of each apparatus,
Modifications can be made as appropriate without departing from the spirit of the present invention.

10 Image forming apparatus 11 Control unit (switching unit)
111 multi-core CPU
112 RAM
12 Operation unit 13 Display unit 14 Image reading unit 15 Image forming unit 16 Communication unit 17 Storage unit

Claims (4)

In an image forming apparatus including a multi-core CPU having a plurality of cores and including a control unit capable of simultaneously controlling a plurality of predetermined operations realized by executing independent programs.
The control unit includes a switching unit that switches between an AMP configuration in which the predetermined operation is individually assigned to each of the plurality of cores and an SMP configuration in which the plurality of cores are used in combination to execute one or a plurality of the predetermined operations. Prepared,
The image forming apparatus, wherein the switching unit switches to the AMP configuration during standby of the predetermined operation and switches to the SMP configuration during the predetermined operation.   The switching unit is a case where a plurality of the predetermined operations are performed in the SMP configuration, and the predetermined operation is performed when there is a predetermined processing period for performing a predetermined process that requires real-time property in the predetermined operations performed. The image forming apparatus according to claim 1, wherein the processing period is switched to the AMP configuration.   When one of a plurality of predetermined operations performed in the SMP configuration is FAX communication, the switching unit switches to the AMP configuration during a period during an incoming call process and a period during a capability exchange process with a partner device. The image forming apparatus according to claim 2.   4. The switch unit according to claim 1, wherein, when the predetermined operation is FAX communication, the switch unit switches to the AMP configuration when waiting for an incoming fax, and switches to the SMP configuration during the FAX communication. The image forming apparatus according to claim 1.

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