JP5251407B2 - Information processing device - Google Patents

Description

  The present invention relates to an information processing apparatus, and more particularly to an improvement of an information processing apparatus having a processor that executes a program written on a memory to which writing is performed by accumulating electric charges in a capacitor.

  In a facsimile apparatus having a printer function for printing received image data on a sheet by electrostatic transfer, preheating control in which the fixing roller is preheated and held at a constant temperature in order to shorten the time required for printing processing at the time of reception. Is done. In recent years, facsimile apparatuses having a power saving mode that consumes less power than during preheating have been proposed (for example, Patent Documents 1 and 2). In the power saving mode, for example, power consumption is reduced by shutting off the power supply to a heater or the like that heats the fixing roller.

  Recently, a main program that performs preheating control as a standby mode, detects a print trigger signal by facsimile reception, etc., and starts a printing process in a printer unit from a nonvolatile ROM to a SDRAM (Synchronous Dynamic Random Access Memory) or the like is faster. It is often read out and used on a volatile memory that operates on the Internet. In such a facsimile apparatus, the main program read by the processor on the volatile memory needs to be executed on the volatile memory. For this reason, even in the power saving mode, the processor must perform a sense-up operation on the volatile memory when reading data accompanying the execution of the program, and the power consumption in the power saving mode There is a problem that it is difficult to further reduce the value.

Therefore, at the time of switching to the power saving mode, it is conceivable that the execution target of the processor is switched from the main program on the volatile memory to the program stored in the ROM in advance, and the power saving operation is performed by the program on the ROM. At this time, if the refresh operation for the volatile memory is stopped, the power consumption in the power saving mode can be further reduced. However, if the refresh operation for the volatile memory stops, the main program on the volatile memory will be lost. Therefore, when returning from the power saving mode to the standby mode, the main program is read again from the ROM and volatile. Had to be written to the memory. For this reason, there has been a problem that it takes a long time to return from the power saving mode to the standby mode.
JP 10-336410 A JP-A-10-336409

  The present invention has been made in view of the above circumstances, and an object thereof is to provide an information processing apparatus that can reduce power consumption in a power saving mode as compared with a conventional apparatus. In particular, an object of the present invention is to reduce power consumption in a power saving mode of an information processing apparatus having a processor that executes a program written on a memory in which writing is performed by accumulating charges in a capacitor. It is another object of the present invention to provide an information processing apparatus capable of reducing power consumption in the power saving mode without increasing the time required for returning from the power saving mode to the standby mode.

An information processing apparatus according to a first aspect of the present invention includes a first memory in which writing is performed by injecting electrons into a floating gate, a second memory in which writing is performed by accumulating charges in a capacitive element, and a second memory An information processing apparatus having a processor for executing a program written thereon, wherein the first program and the second program are stored in the first memory and executed by the processor, and the second program is stored in the second memory. And a switching unit for determining whether or not the second program switches the operation mode from the standby mode to the power saving mode. and instructions, on the basis of the determination result of the switching determination procedure, address indicating the execution position of the second program Writes information to the first memory, and a execution target switching procedure for switching the execution target of the processor to the first program on the first memory, the first program, instructs the start of the refresh operation in the refresh unit refreshing Based on the instruction procedure and the trigger signal for canceling the power saving mode, the refresh unit is instructed to end the refresh operation, and the execution target of the processor is switched to the second program on the second memory. An execution target switching procedure for resuming the operation from the execution position based on the address information written in the memory .

  In this information processing apparatus, the execution target of the processor is switched to the first program on the first memory based on the determination result of whether or not the operation mode is switched from the standby mode to the power saving mode, and the refresh unit starts the refresh operation. Is instructed. Here, the second memory in which writing is performed by accumulating charges in the capacitor element is a volatile memory that requires a sense-up operation by the processor when data is read as the program is executed. On the other hand, the first memory in which writing is performed by injecting electrons into the floating gate does not require a refresh operation for memory retention, and the sense-up operation by the processor at the time of reading data accompanying the execution of the program This is a non-volatile memory that does not need to be used. Here, the sense-up operation is a memory holding operation performed when the processor reads back data from the memory cell and the processor writes back the same data to the memory cell. On the other hand, the refresh operation is a memory holding operation that is performed by replenishing charges to all the capacitive elements at regular intervals.

  According to such a configuration, by switching the execution target of the processor to the first program on the first memory, the processor does not perform a sense-up operation on the second memory when reading data accompanying the execution of the program. Therefore, the power consumption in the power saving mode can be reduced as compared with the conventional apparatus. In particular, by optimizing the charge replenishment interval by the refresh unit that refreshes the second memory asynchronously with the processor, the power consumption can be suppressed as compared with the refresh time by the processor, so that the power consumption in the power saving mode is further increased. Can be reduced. In the power saving mode, the refresh unit is instructed to start the refresh operation, and the second program written in the second memory is held as it is, so the time required for returning from the power saving mode to the standby mode is increased. Therefore, the power consumption in the power saving mode can be reduced.

An information processing apparatus according to a second aspect of the present invention includes a printer unit that prints image data on paper in addition to the above-described configuration, and the second program controls the printer unit and outputs a print trigger signal that is the trigger signal. Based on the print trigger signal, the first program instructs the refresh unit to end the refresh operation, and sets the execution target of the processor as the first execution target. The second program on the second memory is switched , and the operation is resumed from the execution position based on the address information written in the first memory . According to such a configuration, the refresh unit is instructed to end the refresh operation based on the print trigger signal, and the execution target of the processor is switched to the second program in the second memory. The operation mode can be automatically returned from the power saving mode to the standby mode by using the print trigger signal to be started.

  According to the information processing apparatus of the present invention, by switching the execution target of the processor to the first program on the first memory, the processor performs a sense-up operation on the second memory when reading data associated with the execution of the program. Since this is not necessary, the power consumption in the power saving mode can be reduced as compared with the conventional apparatus. In particular, by optimizing the charge replenishment interval by the refresh unit that refreshes the second memory asynchronously with the processor, the power consumption can be suppressed as compared with the refresh time by the processor, so that the power consumption in the power saving mode is further increased. Can be reduced. In the power saving mode, the refresh unit is instructed to start the refresh operation, and the second program written in the second memory is held as it is, so the time required for returning from the power saving mode to the standby mode is increased. Therefore, the power consumption in the power saving mode can be reduced.

  FIG. 1 is a block diagram showing an example of a schematic configuration of an information processing apparatus according to an embodiment of the present invention. As an example of the information processing apparatus, a multifunction machine 1 having a facsimile (FAX) transmission / reception function and a printing function is shown. ing. The multifunction device 1 includes a power supply unit 10, a CPU 20, a FAX transmission / reception unit 21, an operation unit 22, a paper detection unit 23, a scanner unit 24, a flash memory 25, an SDRAM 26, a printer unit 29, a display control unit 32, an LCD 33, and a backlight. 34.

  The power supply unit 10 is a power supply device that converts AC commercial power into DC and supplies it to the CPU 20, FAX transmission / reception unit 21, operation unit 22, paper detection unit 23, scanner unit 24, printer unit 29, and display control unit 32. Yes, power supply is started by turning on the power SW11.

  The CPU 20 is a processor that executes programs on the flash memory 25 and the SDRAM and performs arithmetic processing on various data.

  The FAX transmission / reception unit 21 is a communication unit that performs FAX transmission / reception of image data via a PSTN (Public Switched Telephone Networks). The operation unit 22 includes various operation keys such as a start key, and is a key input unit that receives an operation of an operation key by an operator and generates an input signal corresponding to the operated key. The paper detection unit 23 performs an operation of detecting paper stored in a storage unit such as a paper feed tray in order to operate an ADF (Automatic Document Feeder).

  The scanner unit 24 is a document reading unit that generates image data by optical reading of a document, and includes a light source device that irradiates light on the document, and an image that receives reflected light from the document and generates image data corresponding to the amount of received light. A sensor and a scanning device that scans the reading position in the horizontal direction and the vertical direction are configured.

  The image data received by FAX and the image data read by the scanner unit 24 are converted into a predetermined file format such as MMR (Modified Modified Read), JPEG (Joint Photographic Experts Group), and stored in the code area in the SDRAM 26. The

  The printer unit 29 is an electrostatic transfer printing unit that prints image data on paper, and includes a photosensitive drum, a charger, a developing device, a transfer device, a fixing device, and the like. The fixing device includes a fixing roller 31 and a heater 30 that heats the fixing roller 31.

  An LCD (Liquid Crystal Display) 33 is a display device that displays an operation state and the like on a screen. The backlight 34 is a light source device that illuminates the LCD 33 from the back. The display control unit 32 performs display control of the LCD 33 and lighting control of the backlight 34.

  The flash memory 25 is a nonvolatile memory in which writing is performed by injecting electrons into the floating gate, and data can be written and erased at any time. More specifically, the flash memory 25 is a kind of EEPROM (Electrically Erasable and Programmable Read Only Memory), and a MOSFET (Metal Oxide Semiconductor Field Effect Transistor) is used as a memory element. Yes.

  That is, in the flash memory 25, writing is performed by applying a high voltage with the MOSFET gate open and injecting electrons into the gate. On the other hand, erasing is performed by extracting electrons from the gate using the tunnel effect between the gate and the drain.

  The flash memory 25 holds a startup program A1, a main program A2, and a power saving program A3. The activation program A1 is an operation program that performs an initial operation after power is turned on, and is a program that is first accessed by the CPU 20 when the power is turned on by turning on the power SW11.

  As an initial operation by the activation program A1, a process of reading the main program A2 in the flash memory 25 onto the SDRAM 26 and switching the execution target of the CPU 20 to the main program A2 written on the SDRAM 26 is performed. That is, the activation program A1 has a transfer procedure for transferring the main program A2 from the flash memory 25 to the SDRAM 26, an execution target switching procedure for switching the execution target of the CPU 20 from the startup program A1 to the main program A2 written on the SDRAM 26, and the like. Such a startup program A1 is stored in the boot sector in the flash memory 25.

  The main program A2 is an operation program for performing a standby operation and causing the printer unit 29 to start a printing process on the basis of a facsimile transmission / reception by the FAX transmission / reception unit 21 and a print trigger signal by reading a document by the scanner unit 24. The standby operation includes preheating control for controlling the heater 30 of the printer unit 29 to keep the fixing roller 31 at a constant temperature, and processing for detecting a print trigger signal that instructs the printer unit 29 to start the printing process. Is called. Further, a process of switching the execution target of the CPU 20 to the power saving program A3 on the flash memory 25 and a process of turning on the backlight 34 by controlling the display control unit 32 are also performed.

  As a print trigger signal, a facsimile incoming signal from the FAX transmission / reception unit 21, an input signal based on a key operation for instructing printing, a detection signal from the paper detection unit 23, or received from another terminal device via a LAN A reception signal of a print command packet is assumed. For example, image data designated in advance as a print job is read from the SDRAM 26 and printed by the printer unit 29.

  The power saving program A3 is an operation program for performing a power saving operation. As the power saving operation, a process of cutting off power supply to the heater 30 and the display control unit 32 and reducing power consumption compared to the standby operation is performed. . Further, processing for detecting the print trigger signal and processing for switching the execution target of the CPU 20 to the main program A2 on the SDRAM 26 are performed based on the detection result.

  The activation program A1, the main program A2, and the power saving program A3 are stored in predetermined storage areas in the flash memory 25, respectively.

  The SDRAM 26 is a volatile memory in which writing is performed by accumulating electric charges in a capacitor element, and data can be written and erased at any time. More specifically, the SDRAM 26 is a DRAM whose input / output interface operates in synchronization with the CPU 20, and a capacitor is used as a storage element. That is, in the SDRAM 26, writing is performed by accumulating charges in a capacitor, and data is read by moving charges from the capacitor to the data line.

  The SDRAM 26 is configured by forming on one chip a memory cell unit 27 composed of a large number of capacitive elements and a refresh unit 28 that refreshes the memory cell unit 27 asynchronously with the CPU 20. In this SDRAM 26, a refresh operation is performed in which memory is held by replenishing charges for all the capacitive elements at regular intervals. External refresh performed in synchronization with the CPU 20 and a refresh unit 28 There is an internal refresh performed asynchronously. Here, internal refresh performed asynchronously with the CPU 20 is referred to as self-refresh.

  The memory cell unit 27 of the SDRAM 26 holds a plurality of image data B1 such as image data received by FAX and image data read from a document by the scanner unit 24. Each image data B1 is compressed in a predetermined file format, and is stored as a compressed data in a predetermined code area in the memory cell unit 27.

  FIG. 2 is a block diagram illustrating a configuration example of a main part of the multifunction machine 1 in FIG. 1, and illustrates an example of a functional configuration in the CPU 20. The CPU 20 includes an initial operation execution unit 41, a preheating control unit 43, a print control unit 44, a switching determination unit 45 and an execution target switching unit 46, a refresh instruction unit 48, and a power supply control unit 49. And a power saving operation executing unit 47 including the execution target switching unit 50.

  The initial operation execution unit 41 is a program execution unit that accesses the flash memory 25 and performs an initial operation based on the activation program A1 on the flash memory 25. As an initial operation, the main program A2 is read from the flash memory 25 to a predetermined area in the SDRAM 26, and the execution target of the CPU 20 is switched from the activation program A1 on the flash memory 25 to the main program A2 on the SDRAM 26.

  The standby operation execution unit 42 is a program execution unit that accesses the SDRAM 26 and performs a standby operation based on the main program A2 on the SDRAM 26. The preheating control unit 43 controls the heater 30 of the printer unit 29 and performs an operation of keeping the fixing roller 31 at a constant temperature as a standby mode.

  The print control unit 44 detects the print trigger signal and performs an operation for causing the printer unit 29 to start the printing process based on the detection result. During the printing process by the printer unit 29, the heater 30 is controlled to raise the temperature of the fixing roller 31 more than in the standby mode.

  The switching determination unit 45 performs an operation of determining whether or not to switch the operation mode from the standby mode to the power saving mode. For example, whether or not to switch to the power saving mode based on the time that has passed since the last print processing was completed in order to automatically switch to the power saving mode when the standby state has continued for a certain period of time. Is determined. Alternatively, in order to automatically switch to the power saving mode at a specific time, it is determined whether or not to switch to the power saving mode based on preset time information.

  The execution target switching unit 46 performs an operation of switching the execution target of the CPU 20 from the main program A2 on the SDRAM 26 to the power saving program A3 on the flash memory 25 based on the determination result by the switching determination unit 45.

  The power saving operation execution unit 47 is a program execution unit that accesses the flash memory 25 and performs a power saving operation based on the power saving program A3 on the flash memory 25. The refresh instruction unit 48 performs an operation to instruct the refresh unit 28 of the SDRAM 26 to start a refresh operation when the operation mode is switched from the standby mode to the power saving mode. For example, when the CPU 20 inputs a predetermined start command to the refresh unit 28, the SDRAM 26 is switched from the external refresh mode to the self refresh mode.

  The power supply controller 49 performs an operation of cutting off the power supply to the heater 30 and reducing the power consumption as compared with the standby mode as the power saving mode. Specifically, an operation for lowering the temperature of the fixing roller 31 than in the standby mode is performed by controlling the power supply unit 10 and shutting off the power supply to the heater 30.

  The power supply control unit 49 also controls the display control unit 32 to turn off the backlight 34.

  The execution target switching unit 50 detects the print trigger signal, instructs the refresh unit 28 to end the refresh operation based on the detection result, and changes the execution target of the CPU 20 from the power saving program A3 on the flash memory 25 to the SDRAM 26. Switching to the main program A2. That is, when the CPU 20 instructs the refresh unit 28 to end the refresh operation, the self-refresh mode of the SDRAM 26 is released.

  FIG. 3 is a diagram showing an example of the operation of the multifunction machine 1 of FIG. 1, and schematically shows the operation after the power is turned on. In the flash memory 25, a boot sector 51, a storage area 52 for the main program A2, and a storage area 53 for the power saving program A3 are formed in advance, and the startup program A1, the main program A2, and the power saving program A3 are respectively stored. Yes.

  On the other hand, a predetermined storage area 61 for storing the program transferred from the flash memory 25 and a code area 62 for storing the image data B1 are formed in the memory cell portion 27 of the SDRAM 26.

  When the power supply is started by turning on the power SW11, the CPU 20 accesses the boot sector 51 in the flash memory 25 and executes the startup program A1 stored in the boot sector 51 to perform an initial operation ( Step S1).

  In this initial operation, the main program A2 is read from the storage area 52 in the flash memory 25 and written to the storage area 61 in the SDRAM 26. When the CPU 20 ends the initial operation by switching the execution target to the main program A2 on the SDRAM 26 (step S2), the CPU 20 performs a standby operation based on the main program A2 stored in the storage area 61 (step S3).

  When the CPU 20 changes the operation state from the standby mode to the power saving mode during the standby operation, the CPU 20 switches the execution target to the power saving program A3 on the flash memory 25 (step S4) and performs the power saving operation (step S5). In the CPU 20, when the execution target is switched to the power saving program A3, an operation of writing address information indicating the execution position of the main program A2 in the flash memory 25 is performed.

  In the power saving operation, the SDRAM 26 is switched to the self-refresh mode, and an operation for detecting the input of the print trigger signal is performed. When the input of the print trigger signal is detected, the power saving mode is canceled. When the power saving mode is cancelled, the CPU 20 cancels the self-refresh mode of the SDRAM 26, switches the execution target to the main program A2 on the SDRAM 26 (step S6), and resumes the standby operation (step S7).

  In the CPU 20, when the execution target is switched to the main program A2 on the SDRAM 26, an operation for resuming the standby operation from the execution position immediately before the transition to the power saving mode is performed based on the address information written in the flash memory 25. .

  Steps S101 to S115 in FIG. 4 are flowcharts showing an example of the operation of the multifunction machine 1 in FIG. First, when the power supply is started by turning on the power SW11, the initial operation execution unit 41 of the CPU 20 accesses the boot sector 51 in the flash memory 25 and executes the start program A1 to perform the initial operation. (Step S101).

  At this time, the main program A2 in the flash memory 25 is copied to the SDRAM 26, and the execution target is switched to the main program A2 on the SDRAM 26 (steps S102 and S103).

  Next, the standby operation execution unit 42 executes the main program A2 on the SDRAM 26 to perform a standby operation (step S104). At this time, if the input of the print trigger signal is detected, the printing process by the printer unit 29 is started (steps S105 and S115). On the other hand, when a state where no print trigger signal is input has passed for a certain period of time, the operation mode is switched to the power saving mode (steps S105 and S106).

  When the operation mode is switched to the power saving mode, the standby operation execution unit 42 writes address information indicating the execution position of the main program A2 in the flash memory 25 (step S107), and sets the execution target as the power saving program on the flash memory 25. Switch to A3 (step S108).

  Next, the power saving operation execution unit 47 executes the power saving program A3 on the flash memory 25, switches the SDRAM 26 to the self-refresh mode, and detects the input of the print trigger signal (steps S109 and S110). . At this time, if the input of the print trigger signal is detected, the power saving mode is canceled and the self refresh mode of the SDRAM 26 is canceled (steps S111 and S112). Then, the execution target is switched to the main program A2 on the SDRAM 26 (step S113), the standby operation is resumed, and the printing process is started (step S114). After the printing process is completed, the processing procedure after step S105 is repeated.

  According to the present embodiment, by switching the execution target of the CPU 20 to the power saving program A3 on the flash memory 25, the CPU 20 does not perform a sense-up operation on the SDRAM 26 when reading data accompanying the execution of the program. Therefore, the power consumption in the power saving mode can be reduced as compared with the conventional device. In particular, by optimizing the charge replenishment interval by the refresh unit 28 that refreshes the SDRAM 26 asynchronously with the CPU 20, the charge replenishment interval can be maximized as compared with refreshing in synchronization with the CPU 20. Therefore, power consumption can be suppressed and power consumption in the power saving mode can be further reduced. In the power saving mode, the refresh unit 28 is instructed to start the refresh operation, and the main program A2 written in the SDRAM 26 is held as it is, so that the time required for returning from the power saving mode to the standby mode is increased. Therefore, power consumption in the power saving mode can be reduced.

  Further, based on the print trigger signal, the refresh unit 28 is instructed to end the refresh operation, and the execution target of the CPU 20 is switched to the main program A2 on the SDRAM 26. Therefore, the print trigger signal for causing the printer unit 29 to start the printing process is provided. By using this, the operation mode can be automatically returned from the power saving mode to the standby mode.

  In the present embodiment, an example in which the flash memory 25 is used as a nonvolatile memory that holds the activation program A1, the main program A2, and the power saving program A3 has been described. However, the present invention is not limited to this. Absent. The non-volatile memory that holds the start program A1, the main program A2, and the power saving program A3 may be any other memory as long as writing is performed by injecting electrons into the floating gate.

  Further, in the present embodiment, an example in which SDRAM 26 is used as a volatile memory in which writing is performed by accumulating charges in a capacitor element and refresh unit 28 that refreshes memory cell unit 27 asynchronously with CPU 20 is used. However, the present invention is not limited to this. Instead of SDRAM, DRAM, DDR (Double Data Rate) -SDRAM, DDR2-SDRAM, DDR3-SDRAM, or the like may be used. Here, the DDR-SDRAM is an SDRAM in which data transfer is speeded up, and data is input / output using both rising and falling edges of a clock signal.

  The present invention also includes a refresh unit that refreshes the memory cell unit asynchronously with the CPU 20 on a separate chip from the memory cell unit.

  In the present embodiment, an example in which the CPU 20 transfers the main program A2 to the SDRAM 26 based on the activation program A1 on the flash memory 25 has been described, but the present invention is not limited to this. For example, the present invention includes a case in which a controller separate from the CPU 20 transfers the main program A2 from the flash memory 25 to the SDRAM 26 without the CPU 20 interposed.

1 is a block diagram illustrating an example of a schematic configuration of an information processing apparatus according to an embodiment of the present invention, in which a multifunction machine 1 having a facsimile transmission / reception function and a printing function is illustrated. FIG. 2 is a block diagram illustrating a configuration example of a main part of the multifunction machine 1 in FIG. 1, illustrating an example of a functional configuration in a CPU 20. FIG. 2 is a diagram showing an example of the operation of the multifunction machine 1 of FIG. 1, schematically showing the state of operation after power-on. 3 is a flowchart illustrating an example of the operation of the multifunction machine 1 in FIG. 1.

Explanation of symbols

1 MFP 10 Power Supply Unit 11 Power SW
20 CPU
21 FAX transmission / reception unit 22 Operation unit 23 Paper detection unit 24 Scanner unit 25 Flash memory 26 SDRAM
27 Memory cell unit 28 Refresh unit 29 Printer unit 30 Heater 31 Fixing roller 32 Display control unit 33 LCD
34 Backlight 41 Initial operation execution unit 42 Standby operation execution unit 43 Preheating control unit 44 Print control unit 45 Switching determination unit 46 Execution target switching unit 47 Power saving operation execution unit 48 Refresh instruction unit 49 Power supply control unit 50 Execution target switching unit A1 Startup program A2 Main program A3 Power saving program

Claims (2)

A first memory in which writing is performed by injecting electrons into the floating gate; a second memory in which writing is performed by accumulating charges in the capacitor; and a processor that executes a program written in the second memory; In an information processing apparatus having
A first program and a second program held on the first memory and executed by the processor;
A transfer unit for transferring the second program to the second memory;
A refresh unit that refreshes the second memory asynchronously with the processor;
The second program includes a switching determination procedure for determining whether or not to switch the operation mode from the standby mode to the power saving mode;
An execution target switching procedure for writing address information indicating the execution position of the second program to the first memory based on the determination result in the switching determination procedure and switching the execution target of the processor to the first program on the first memory. Have
The first program instructs the refresh unit to end the refresh operation based on a refresh instruction procedure for instructing the refresh unit to start a refresh operation and a trigger signal for releasing the power saving mode, and the processor And an execution target switching procedure for switching the execution target to the second program on the second memory and restarting the operation from the execution position based on the address information written in the first memory. apparatus. A printer unit that prints image data on paper;
The second program has a print control procedure for controlling the printer unit and causing the printer unit to start print processing based on a print trigger signal that is the trigger signal.
The first program instructs the refresh unit to end the refresh operation based on the print trigger signal, switches the execution target of the processor to the second program on the second memory, and writes the first program to the first memory. The information processing apparatus according to claim 1, wherein the operation is resumed from the execution position based on address information .

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