Information processing device, and control method of the same as well as program

What is AI technical title?
AI technical title is built by Patsnap AI team. It summarizes the technical point description of the patent document.
The information processing device addresses the challenge of power saving in low-power modes by using an operation acceptance and power control system to manage power states and reduce standby power consumption in the operation unit.

JP2025046041APending Publication Date: 2025-04-02CANON KK

View PDF 1 Cites 0 Cited by

Patent Information

Application Number: JP2023154188
Authority / Receiving Office: JP · JP
Patent Type: Applications
Current Assignee / Owner
Filing Date: 2023-09-21
Publication Date: 2025-04-02

AI Technical Summary

Technical Problem

Existing information processing devices, such as image forming apparatuses, face challenges in power saving during low-power modes, as they continue to consume standby power in the operation unit even when in power saving mode.

Method used

The device incorporates an operation acceptance means to accept user operations, a control unit to process these signals, a generation unit to generate return signals, and a power control unit that transitions the device between power states, ensuring the operation unit is powered down when not in use, thereby achieving power saving.

Benefits of technology

This solution allows the device to operate in a low-power state without the sub-CPU being energized, while still enabling user interactions to transition to a powered state, resulting in effective power saving for the operation unit.

✦ Generated by Eureka AI based on patent content.

Smart Images

Figure 2025046041000001_ABST

Patent Text Reader

Abstract

To enable a mode to be returned from a sleep mode by touch panel operation in order to secure convenience of a user and achieve power saving of an operation part by eliminating power consumption by an unnecessary portion in an operation part.SOLUTION: An information processing device is provided with: an operation part that receives operation from a user; a control part that receives a signal from the operation part; a generation part that receives the signal from the operation part and generates a return signal; and power supply control means that transfers an electric power state of the information processing device from a first electric power state in which electric power is not distributed to the control part into a second electric power state in which electric power is distributed to the control part, on the basis of the return signal. In the second electric power state, the generation part does not generate the return signal even when receiving a signal from the operation part. In the first electric power state, the generation part generates the return signal when receiving a signal from the operation part.SELECTED DRAWING: Figure 5

Need to check novelty before this filing date? Find Prior Art

Description

[Technical field]

[0001] The present invention relates to an information processing device, a control method thereof, and a program. [Background technology]

[0002] An information processing device such as an image forming device may include a dedicated operation unit that is configured with an input device such as a touch panel or a numeric keypad, a display device such as an LCD (liquid crystal display), a control board equipped with a CPU, etc. The operation unit is configured to receive image data generated by a main control unit of the information processing device from the main control unit, and to perform a screen display on the display device based on the received image data.

[0003] On the other hand, power saving is required for such information processing devices, and a technology is known that achieves power saving by switching devices to which power is supplied according to the state of the power saving mode when the information processing device operates in the power saving mode. The technology disclosed in Patent Document 1 has a circuit in the operation unit that detects operations by the user, and switches devices to which power is supplied to parts related to printing operations and information processing operations based on an input instruction from the user. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] JP 2019-59175 A Summary of the Invention [Problem to be solved by the invention]

[0005] However, the technology disclosed in Patent Document 1 is configured such that the power supply of the operation unit is not turned off even in the power saving mode in order to detect operations from the user.

[0006] Therefore, there is no control for reducing the power supply of the operation unit itself, and the standby power consumption of the operation unit itself during the power saving mode becomes large.

[0007] In consideration of the above problems, the object of the present invention is to, when an information processing device operates in a first power state in which no power is applied to the sub-CPU, ensure the convenience of being able to transition from the first power state in which no power is applied to the sub-CPU to a second power state in which power is applied to the sub-CPU upon receiving an operation from a user, while achieving power savings in the operation unit by removing power from unnecessary parts of the operation unit at least in the first power state without applying power to the sub-CPU. [Means for solving the problem]

[0008] In order to achieve the above-mentioned object, the information processing device of the present invention comprises an operation receiving means for receiving operations from a user, a control unit for receiving a signal from the operation receiving means, a generation unit for receiving the signal from the operation receiving means and generating a return signal, and a power control means for transitioning the power state of the information processing device from a first power state in which no power is supplied to the control unit to a second power state in which power is supplied to the control unit based on the return signal, wherein in the second power state, the generation unit does not generate the return signal even when it receives a signal from the operation receiving means, and in the first power state, the generation unit generates the return signal when it receives a signal from the operation receiving means. Effect of the Invention

[0009] According to the present invention, when an information processing device operates in a first power state in which no power is applied to the sub-CPU, the convenience of being able to transition from the first power state in which no power is applied to the sub-CPU to a second power state in which power is applied to the sub-CPU upon receiving an operation from a user is ensured, while at the same time, in the first power state, it is possible to achieve power saving in the operation unit by removing power from unnecessary parts of the operation unit without applying power to at least the sub-CPU. [Brief description of the drawings]

[0010] [Figure 1] A block diagram showing an example of the configuration of an image forming system. [Diagram 2] FIG. 2 is a block diagram showing an example of the hardware configuration of the image forming apparatus 200. [Diagram 3] A block diagram showing an example of the hardware configuration of a power reset control unit 234. [Figure 4] A block diagram showing an example of the hardware configuration of a reset control unit 306. [Diagram 5] (A) A block diagram showing an example of the hardware configuration of the return signal generating unit 235. (B) A block diagram showing the power supply state of each block connected to the return signal generating unit 235 in a power saving state. [Figure 6] FIG. 1 is a timing chart showing an example of the behavior of internal signals and main power / power signals input / output of the power reset generating unit 234 in the first embodiment. [Figure 7] FIG. 1 is a timing chart showing an example of the behavior of internal signals and main power / power signals input / output of the power reset generating unit 234 in the first embodiment. [Figure 8] FIG. 11 is a timing chart showing an example of the behavior of internal signals and main power / power signals input / output of the power reset generating unit 234 in the second embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0011] Hereinafter, the embodiments will be described with reference to the drawings. However, the components described in the following embodiments are merely examples, and the present invention is not limited to these.

[0012] Example 1 <System configuration> FIG. 1 is a diagram showing an example of the configuration of an image forming system according to an embodiment. In this embodiment, an example in which this embodiment is applied to an image forming apparatus that forms an image will be described as an example of an information processing apparatus. This embodiment is applicable to any information processing apparatus that has a control unit that generates image data for screen display, and a display unit that displays a screen on the display unit based on the image data generated by the control unit, and an operation unit that accepts user operations. For example, this embodiment is also applicable to information processing apparatuses such as printing devices, reading devices, copiers, and facsimile machines.

[0013] 1, a PC (personal computer) 101, a server 102, and an image forming apparatus 200 are connected to a LAN 104. The server 102 is a computer that provides a service in response to a request from a client apparatus such as the PC 101 or the image forming apparatus 200.

[0014] The PC 101 or the server 102 generates a print job including data written in a print language such as PDL or data in a specific data format (compressed with JBIG or the like) according to a user operation. The PC 101 or the server 102 transmits the generated print job to the image forming apparatus 200 via the LAN 104. When the image forming apparatus 200 receives a print job from an external device such as the PC 101 or the server 102, it executes image formation (printing) according to the received print job.

[0015] The PC 101 or the server 102 can remotely access the image forming apparatus 200 via the LAN 104. The PC 101 or the server 102 is configured to be able to operate the image forming apparatus 200 and monitor the status of the image forming apparatus 200 through the remote access. The image forming apparatus 200 is also configured to be able to notify an external device such as the PC 101 or the server 102 of its own status.

[0016] <Configuration of Image Forming Apparatus 200> 2 is a block diagram showing an example of a hardware configuration of the image forming apparatus 200. The image forming apparatus 200 includes a main control unit 201, an operation unit 216, a printer unit 218, and a scanner unit 219.

[0017] The main control unit 201 includes a main CPU 202 (first CPU), and controls the image forming apparatus 200 as a whole.

[0018] The operation unit 216 functions as a user interface (UI) and includes a sub-CPU 208 (second CPU), an input device (touch panel 211) that accepts user operations, and a display device (LCD unit 212) that displays a screen. In this embodiment, the touch panel 211 and the touch panel control unit 210 are collectively referred to as an operation acceptance means.

[0019] In this embodiment, the main control unit 201 functions as an example of a control unit that generates image data for display on the screen of the LCD unit 212 and outputs the image data to the operation unit 216 .

[0020] The operation unit 216 has an LCD unit 212 (display unit), displays a screen on the LCD unit 212 (display unit) based on image data generated by the main control unit 201, and functions as an example of an operation unit that accepts user operations.

[0021] The image data for screen display is not limited to being generated by the main control unit 201 as in this embodiment, but may be generated by the sub-CPU 208 in the operation unit 216 or the like.

[0022] The printer unit 218 performs image formation processing on a sheet-shaped recording medium (paper) according to, for example, an electrophotographic method. Note that the printer unit 218 is not limited to the electrophotographic method, and may employ other recording methods such as an inkjet method or a thermal transfer method.

[0023] The main control unit 201 includes a main CPU 202, a ROM 203, a RAM 204, a STORAGE 205, a LAN controller 206, and a power supply control unit 250. The main control unit 201 realizes a print function by controlling the printer unit 218 to print an image according to a print job received from an external device, for example. The main control unit 201 also realizes a copy function by controlling the scanner unit 219 and the printer unit 218 to print an image based on image data obtained by reading an original image with the scanner unit 219.

[0024] The main CPU 202 controls the entire image forming apparatus 200. The main CPU 202 realizes the functions of the image forming apparatus 200, such as a print function and a copy function, by reading and executing a program stored in the ROM 203 or the STORAGE 205. The RAM 204 is composed of a volatile memory such as a DDR SDRAM. The RAM 204 is used to store the program executed by the main CPU 202 and temporary data used by the main CPU 202. The STORAGE 205 is a storage device such as an SSD (Solid State Drive) connected to the main CPU 202 by a serial ATA. The STORAGE 205 is used to temporarily store various setting information related to the image forming apparatus 200 and image data used in the print function or the copy function. The LAN controller 206 is connected to the main CPU 202 and the LAN 104. The LAN controller 206 controls communication with an external device, such as the PC 101 or the server 102, via the LAN 104.

[0025] The image forming apparatus 200 of this embodiment has a first power saving mode, a second power saving mode, and a standby mode as operation modes. In the standby mode, the main CPU 202 is supplied with power from a power source (not shown) and is in an operable state.

[0026] In the first power saving mode, power is not supplied from the power source to the main CPU 202, and the main CPU 202 is not in an operable state. The first power saving mode is an operation mode in which the image forming apparatus 200 consumes less power than the second power saving mode and the standby mode. In the first power saving mode, power supply to devices such as the printer unit 218 and the scanner unit 219 is also stopped.

[0027] In the second power saving mode, power is supplied from the power supply to the main CPU 202, and the main CPU 202 is in a partially operable state. The second power saving mode is an operation mode in which the image forming apparatus 200 consumes less power than the standby mode, but consumes more power than the first power saving mode. Note that in the second power saving mode, power supply to devices such as the printer unit 218 and the scanner unit 219 is also stopped.

[0028] In this embodiment, a power supply (not shown) for the image forming apparatus 200 is provided in the main control unit 201.

[0029] The power supply control unit 250 performs power supply control of the entire image forming apparatus 200. When power is not supplied to the main CPU 202 and the printer unit 218 / scanner unit 219, the power supply control unit 250 performs on / off control of the power supply in the image forming apparatus 200 provided in the main control unit 201. When power is supplied to the main CPU 202 and the printer unit 218 / scanner unit 219, the main CPU 202 controls the power supply control unit 250 to perform on / off control of the power supply to each unit. The power supply control by the power supply control unit 250 may be realized by the CPU of the power supply control unit executing a program, or may be realized by hardware logic such as a PLD (Programmable Logic Device).

[0030] The power supply control unit 250 performs on / off control of the power supply in the image forming apparatus 200 using a return signal 2033 from the operation unit 216 or a return signal (not shown) from the LAN controller 206 as a trigger. As a result, the power supply control unit 250 transitions the image forming apparatus 200 from the first and second power saving modes to the standby mode. Furthermore, the power supply control unit 250 controls the power supply V1 (described later in FIG. 3) to the operation unit 216.

[0031] The operation unit 216 is connected to the main control unit 201 via an image data signal 2008, a communication signal 2009, and a communication signal 2010. The operation unit 216 is further connected to the main control unit 201 via a READY signal 2031, a READY signal 2032, a return signal 2033, a first mode notification signal 2050, and a second mode notification signal 2053.

[0032] The READY signal 2031 is a signal indicating that the sub CPU 208 is in an operable state (a state in which the communication signal 2010 can be received).

[0033] The READY signal 2032 is a signal indicating that the image output unit 209 is in a state capable of receiving the communication signal 2009 and the image data signal 2008, and is a signal sent from the image output unit 209 to the main CPU 202 and the sub CPU 208 in the operation unit 214.

[0034] The return signal 2033 is a signal for returning the main control unit 201 (image forming apparatus 200) from a sleep state (power saving mode), and is transmitted from the return signal generation unit 235 to the power supply control unit 250.

[0035] The first mode notification signal 2050 and the second mode notification signal 2053 are signals for notifying the power mode of the main control unit 201 (image forming apparatus 200) to the power reset control unit 234 of the operation unit 214. The power mode here indicates whether the power mode is the first power saving mode, the second power saving mode, or the standby mode.

[0036] An image output unit 209 of the operation unit 216 receives instructions or information from the main control unit 201 via an image data signal 2008 , a communication signal 2009 , and a communication signal 2010 , and controls the display of the LCD unit 212 .

[0037] In addition, the operation unit 216 notifies the main control unit 201 of a user operation received via the touch panel 211 via a communication signal 2010 .

[0038] The power reset control unit 234 of the operation unit 216 determines (discriminates) the current operation mode of the main control unit 201 by monitoring the first mode notification signal 2050 and the second mode notification signal 2053. Specifically, the operation unit 216 determines whether the operation mode of the main control unit 201 is the first power saving mode, the second power saving mode, or the standby mode.

[0039] Meanwhile, the main CPU 202 determines whether the sub CPU 208 is in an operable state (a state in which the communication signal 2010 can be received) by monitoring the READY signal 2031. The main CPU 202 further determines whether the image output unit 209 is in a state in which the communication signal 2009 and the image data signal 2008 can be received by monitoring the READY signal 2032.

[0040] The operation unit 216 includes an operation unit control unit 214 , a touch panel 211 , an LCD unit 212 , and a speaker 213 .

[0041] The operation unit control unit 214 includes a sub CPU 208, a touch panel control unit 210, an image output unit 209, a power reset control unit 234, and a return signal generation unit 235.

[0042] The touch panel control unit 210 is connected to the sub CPU 208 , the touch panel 211 , and the return signal generation unit 235 .

[0043] The touch panel control unit 210 is connected to the touch panel 211 via a control signal 2001, and detects a touch input to the touch panel 211 by monitoring the control signal 2001.

[0044] Furthermore, the touch panel control unit 210 uses a touch detection signal 2002 to notify the sub CPU 208 and the return signal generating unit 235 of detection information indicating that a touch input has been made to the touch panel 211 by the user.

[0045] Furthermore, the touch panel control unit 210 communicates with the sub CPU 208 via a control signal 2003 .

[0046] Sub-CPU 208 is also called an operation unit CPU, and transmits setting information for appropriately detecting touch input, such as correcting touch sensitivity and touch coordinate deviation for touch panel 211, to touch panel control unit 210 via control signal 2003.

[0047] Furthermore, the sub CPU 208 receives, via a touch detection signal 2002, detection information indicating that a touch input has been made to the touch panel 211 from the touch panel control unit 210.

[0048] Furthermore, when the sub CPU 208 receives a detection signal from the touch panel control unit 210, it reads out input operation data corresponding to the user's input operation from the touch panel control unit 210 via the control signal 2003. The input operation data here is data such as touched coordinates and pressing pressure.

[0049] The sub CPU 208 transmits the input operation data received from the touch panel control unit 210 to the main CPU 202 via a communication signal 2010 .

[0050] The image output unit 209 is connected to the LCD unit 212 and controls image display on the LCD unit 212. That is, the image output unit 209 functions as an example of an image output circuit that generates an image signal for screen display based on image data received from the main control unit 201 and outputs the image signal to the LCD unit 212. The image output unit 209 controls the LCD unit 212 using an image output signal 2005 and a backlight control signal 2021. The backlight control signal 2021 is used for on / off control (illumination control) of the backlight of the LCD unit 212 and for setting brightness, etc.

[0051] The image output unit 209 is also connected to the main CPU 202 and the sub CPU 208. The image output unit 209 exchanges a control signal 2006 with the sub CPU 208. The image output unit 209 also exchanges an image data signal 2008, a communication signal 2009, and a READY signal 2032 with the main CPU 202.

[0052] The READY signal 2032 is a signal output from the image output unit 209 to the main CPU 202, and is used to notify whether the image output unit 209 is ready to receive the communication signal 2009 and the image data signal 2008 or not.

[0053] The image receiving signal 2022 is output from the image output unit 209 and is used to notify the image output unit 209 from the main CPU 202 whether an image to be displayed on the LCD unit 212 is being received from the image data signal 2008 .

[0054] The image receiving signal 2022 is connected not only to the power reset control section 234 but also to the sub CPU 208 so that the sub CPU 208 can monitor it.

[0055] Also, the READY signal 2032 output from the image output unit 209 is connected not only to the main CPU 202 but also to the sub CPU 208 so that the sub CPU 208 can monitor the READY signal 2032. This allows the sub CPU 208 to monitor the image receiving signal (2022) and the READY signal (2032) indicating whether the image output unit is ready to receive image data.

[0056] The main CPU 202 transmits image data of the screen to be displayed on the LCD unit 212 to the image output unit 209 mounted on the operation unit control unit 214 as an image data signal 2008. The main CPU 202 transmits setting information for setting the screen display, such as the size or orientation of the screen displayed on the LCD unit 212, to the image output unit 209 using the communication signal 2009.

[0057] The image output unit 209 generates an image signal receivable by the LCD unit 212, based on image data received as an image data signal 2008 from the main CPU 202 and setting information received as a communication signal 2009. The image output unit 209 transmits the generated image signal to the LCD unit 212 as an image output signal 2005. The image output unit 209 generates, for example, an LVDS (Low Voltage Differential Signaling) signal or an analog or digital RGB signal as an image signal receivable by the LCD unit 212.

[0058] The LCD unit 212 displays a screen in accordance with the image output signal 2005 received from the image output unit 209 .

[0059] After receiving image data and setting information from the main CPU 202 , when the image output unit 209 becomes capable of outputting an image to the LCD unit 212 , it notifies the power reset control unit 234 using an image receiving signal 2022 .

[0060] The sub CPU 208 controls the image output unit 209 to turn on / off (lighting control) the backlight of the LCD unit 212 and sets the brightness, etc., via the control signal 2006 .

[0061] The sub CPU 208 controls the speaker 213 using the control signal 2004. For example, the sub CPU 208 causes the speaker 213 to output a push sound indicating that a user's input has been accepted, and a sound indicating an operation instruction to the user or information such as the state of the image forming apparatus 200. Note that the speaker 213 may be controlled by the main CPU 202 instead of the sub CPU 208.

[0062] The power reset control unit 234 performs power control and reset control of the entire operation unit 216 .

[0063] The power reset control unit 234 monitors the mode notification signal 2050 from the power control unit 250, and determines whether the main control unit 201 (image forming apparatus 200) is in the first power saving mode, the second power saving mode, or the standby mode.

[0064] Thereafter, the power reset control unit 234 controls the power supply of the entire operation unit 216 by turning on / off the power supply in the operation unit 216 provided in the operation unit control unit 214. Then, like the main control unit 201, the operation unit 216 transitions to the first power saving mode or the second power saving mode, or transitions to the standby mode.

[0065] Furthermore, the power reset control unit 234 notifies the recovery signal generation unit 235 of a power control signal 2051 to generate a recovery signal depending on whether the determined state of the image forming apparatus 200 is the first power saving mode, the second power saving mode, or the standby mode.

[0066] Furthermore, the power reset control section 234 generates a reset signal for devices in the operation section control section 214 by monitoring the on / off state of the power supply in the operation section 216 provided in the operation section control section 214 .

[0067] The power reset control by the power reset control unit 234 may be realized by hardware logic, or may be realized by a CPU such as a microcomputer executing a program.

[0068] The return signal generating unit 235 receives information indicating a change in the user input on the touch panel 211 from the touch panel control unit 210 via a touch detection signal 2002 from the touch panel control unit 210.

[0069] The return signal generating unit 235 generates a return signal 2033 from the received touch detection signal 2002, the return signal 2052 generated by the sub CPU 208, and the power control signal 2051 received from the power reset control unit 234. Thus, by notifying the power control unit 250, the main control unit 201 (image forming apparatus 200) is returned to the standby mode from the first or second power saving mode.

[0070] <Configuration of power reset control unit 234> FIG. 3 is a block diagram showing an example of the hardware configuration of the power reset control unit 234. As shown in FIG.

[0071] The power reset control unit 234 includes a power conversion unit 301 , a power control unit 302 , a first power monitoring unit 303 , a second power monitoring unit 304 , a reset control unit 306 , a switch 307 , a switch 308 , and a switch 309 .

[0072] The power reset control unit 234 is supplied with a power supply V1 from the power supply control unit 250 of the main control unit 201. Here, the power supply V1 is, for example, 12 V DC.

[0073] The power conversion unit 301 converts the supplied power supply V1 into a power supply V2. Here, an example of the power supply V2 is DC 3.3V, and an example of the power supply conversion unit 301 is a regulator that steps down from 12V to 3.3V.

[0074] The power supply V2 is supplied to the touch panel control unit 210 , the return signal generating unit 235 , the power supply control unit 302 , the first power supply monitoring unit 303 , and the reset control unit 306 .

[0075] The power supply control unit 302 monitors the first mode notification signal 2050 and the second mode notification signal 2053 from the power supply control unit 250, and the image receiving signal 2022 from the image output unit 209. Then, it generates a power supply control signal 2051 that controls the ON / OFF of the switch 307, and a power supply control signal 3007 that controls the ON / OFF of the switches 308 and 309.

[0076] The first power supply monitor 303 monitors the voltage of the power supply V2 to monitor whether the power supply V2 is being supplied stably or not, and notifies the reset control unit 306 of a first power supply state notification signal 3003 .

[0077] The second power supply monitor 304 monitors the voltage of the power supply V3 to determine whether the power supply V3 is being supplied stably, and notifies the reset control unit 306 of a second power supply state notification signal 3004 .

[0078] Furthermore, the second power supply monitor 304 monitors the behavior of the voltage of the power supply V3, and notifies the reset control unit 306 of a second power supply rising edge notification signal 3005 only when a rising edge of the power supply V3 is detected.

[0079] The reset control unit 306 generates a reset signal 3001 to the touch panel control unit 210 and a reset signal 3002 to the sub CPU 208 from the first power state notification signal 3003 , the second power state notification signal 3004 , and the second power rising edge notification signal 3005 .

[0080] The switch 307 turns the power supply V 2 on and off based on a power supply control signal 2051 from the power supply control unit 302 , thereby generating the power supply V 3 to be supplied to the sub CPU 208 .

[0081] The switch 308 generates a power supply V 4 to be supplied to the image output unit 209 from the power supply V 2 based on an off-on control signal 3007 from the power supply control unit 302 .

[0082] The switch 309 generates the power supply V5 supplied to the LCD unit from the power supply V1 based on the off-on control signal 3007 from the power supply control unit 302.

[0083] <Configuration of Reset Control Unit 306> FIG. 4 is a block diagram showing an example of the hardware configuration of the reset control unit 306. As shown in FIG.

[0084] The reset control unit 306 is made up of a first reset generation unit 401 and a second reset generation unit 402 .

[0085] The first reset generator 401 generates a reset signal 3001 to the touch panel controller 210 from the first power state notification signal 3003 from the first power monitor 303 and the second power rising edge notification signal 3005 from the second power monitor 304 .

[0086] The second reset generator 402 generates a reset signal 3002 to be sent to the sub CPU 208 from the second power supply state notification signal 3004 from the second power supply monitor 304 .

[0087] <Configuration of the return signal generating unit 235> FIG. 5A is a block diagram showing an example of the hardware configuration of the return signal generating unit 235.

[0088] The return signal generating unit 235 is composed of a return signal masking unit 501 and an OR gate 502 .

[0089] The return signal masking unit 501 performs signal masking on the touch detection signal 2002 from the touch panel control unit 210 using the power supply control signal 2051 from the power supply control unit 302 , and outputs a masked return signal 5001 to the OR gate 502 .

[0090] When the power supply control signal 2051 is ON, the return signal masking unit 501 masks the touch detection signal 2002, and outputs the return signal 5001 as disabled after masking.

[0091] Furthermore, when the power supply control signal 2051 is OFF, the return signal masking unit 501 does not mask the touch detection signal 2002, and outputs the return signal 5001 as enabled after masking.

[0092] The OR gate 502 ORs the return signal 2052 from the sub CPU 208 and the masked return signal 5001 from the return signal masking unit 501 and outputs it as the return signal 2033 .

[0093] Here, as an example of the return signal generating unit 235, an embodiment has been described in which the return signal masking unit 501 and the OR gate 502 are configured with logic circuits, and receive the touch detection signal 2002, invalidate the masked return signal 5001, and output it. However, the present invention is not limited to the embodiment described above, and a CPU or the like may be used, or an embodiment may be used in which the touch detection signal 2002 is received and ignored, or an embodiment in which the touch detection signal 2002 is not received at all.

[0094] FIG. 5B is a block diagram showing the energization state of each block connected to the return signal generating unit 235 in the first power saving state.

[0095] Here, the operation of the recovery signal generating unit 235 in each power state of the image forming apparatus will be described with reference to FIG. 5(A) and FIG. 5(B).

[0096] First, when the image forming apparatus is in the standby mode, as shown in FIG. 5A, the sub-CPU 208 is energized, and the power control signal 2051 from the power control unit 302 is ON.

[0097] Therefore, the touch detection signal 2002 input from the touch panel control unit 210 to the return signal masking unit 501 is masked by the return signal masking unit 501, and after masking, the return signal 5001 is output as disabled.

[0098] On the other hand, the sub CPU 208 uses the touch detection signal 2002 as a trigger for reading out the user's input operation data received by the touch panel 211 via the control signal 2003 from the touch panel control unit 210. This is because the touch detection signal 2002 indicates that a touch input is being made to the touch panel when the user touches the touch panel while an image is being displayed on the LCD unit 212 in the standby mode.

[0099] Therefore, in the standby mode, even if the touch detection signal 2002 is enabled, the sub CPU 208 outputs the return signal 2052 as disabled.

[0100] Next, when the image forming apparatus is in the first power saving mode, as shown in FIG. 5B, no power is applied to the sub-CPU 208, and the power control signal 2051 from the power supply control unit 302 is OFF.

[0101] Therefore, the touch detection signal 2002 input from the touch panel control unit 210 to the return signal masking unit 501 is not masked by the return signal masking unit 501, and the return signal 5001 is enabled and output after masking.

[0102] When the image forming apparatus is in the second power saving mode, power is applied to the sub-CPU 208 as shown in FIG. 5A, and the power control signal 2051 from the power supply control unit 302 is ON.

[0103] Therefore, the touch detection signal 2002 input from the touch panel control unit 210 to the return signal masking unit 501 is masked by the return signal masking unit 501, and after masking, the return signal 5001 is output as disabled.

[0104] On the other hand, the sub CPU 208 uses the touch detection signal 2002 to generate a signal for returning from the second power saving mode. This is because the touch detection signal 2002 indicates that the user is about to return from the power saving mode when no image is displayed on the LCD unit 212 in the second power saving mode and the user touches the touch panel.

[0105] Therefore, in the second power saving mode, when the touch detection signal 2002 is enabled, the sub CPU 208 outputs the return signal 2052 as enabled.

[0106] <Timing chart of main power supplies and signals> FIG. 6 is a timing chart showing an example of the behavior of internal signals of the power reset generation unit 234 and main power / voltage signals input / output.

[0107] At time T1, when a power switch (not shown) is turned ON by a user operation, power supply V1 is first supplied from the power supply control unit 250 of the main control unit 201, and then power supply V2 is generated from power supply V1 by the power supply conversion unit 301, and the startup process of the image forming apparatus is initiated.

[0108] At time T2, when the first power supply monitoring unit 303 detects that the power supply V2 has begun to be supplied stably, it changes the first power supply state notification signal 3003 from LOW to HIGH, and notifies the reset control unit 306 that the power supply V2 is being supplied stably.

[0109] Furthermore, at time T2, the first reset signal generation unit 401 in the reset control unit 306 detects that the first power state notification signal 3003 has changed from LOW to HIGH, and changes the reset signal 3001 to the touch panel control unit 210 from LOW to HIGH, changing the reset state to the reset release state.

[0110] At time T3, first, the power control unit 250 of the main control unit 201 changes the outputs of the first mode notification signal 2050 and the second mode notification signal 2053 from LOW to HIGH to notify the operation unit 216 that the main control unit 201 is starting up.

[0111] The power reset control unit 234 of the operation unit 216 detects that the main control unit 201 is starting up because the outputs of the first mode notification signal 2050 and the second mode notification signal 2053 have changed from LOW to HIGH simultaneously. Furthermore, at time T3, the power control unit 302 of the operation unit 216 changes the first mode notification signal 2050 from LOW to HIGH. Upon detecting that the main control unit 201 is starting up, the power control signal 2051 is changed from LOW to HIGH in order to turn on the switch 307, thereby starting the supply of power V3.

[0112] Furthermore, at time T3, when the power supply control unit 302 detects that the second mode notification signal 2053 has been changed from LOW to HIGH, it changes the power supply control signal 3007 from LOW to HIGH, thereby turning on the switches 308 and 309 and starting the supply of power supplies V4 and V5.

[0113] Furthermore, at time T3, when the second power supply monitor 304 detects that the supply of the power supply V3 has started, it changes the output of the second power supply rising edge notification signal 3005 from LOW to HIGH, thereby notifying the reset control unit 306 that the supply of the power supply V3 has started.

[0114] Furthermore, at time T3, when the first reset generation unit 401 of the reset control unit 306 detects that the second power rising edge notification signal 3005 has changed from LOW to HIGH, it changes the output of the reset signal 3001 from HIGH to LOW, thereby temporarily resetting the touch panel control unit 210.

[0115] At time T4, when the second power supply monitor 304 detects that the power supply V3 has started to be supplied stably, it changes the output of the second power supply state notification signal 3004 from LOW to HIGH, and further changes the output of the second power supply rising edge notification signal 3005 from HIGH to LOW to notify the reset control unit 306 that the power supply V3 has started to be supplied stably.

[0116] Furthermore, at time T4, the first reset signal generation unit 401 of the reset control unit 306 detects that the second power rising edge notification signal 3005 has changed from HIGH to LOW. Then, the first reset signal generation unit 401 of the reset control unit 306 changes the output of the reset signal 3001 to the touch panel control unit 210 from LOW to HIGH again. This releases the touch panel control unit 210 from the reset state.

[0117] Furthermore, at time T4, the second reset signal generating section 402 of the reset control section 306 changes the output of the reset signal 3002 from LOW to HIGH, releasing the sub CPU 208 from the reset state.

[0118] As a result, when transitioning to the standby mode, not only the sub CPU 208 but also the touch panel control unit 210 can be reset.

[0119] At time T5, when the image output unit 209 receives a display image from the main CPU 202 to the LCD unit 212, it changes the image receiving signal 2022 from LOW to HIGH. Then, it notifies the LCD unit 212 that it has started receiving a display image from the main CPU 202, and starts displaying the image on the LCD unit 212.

[0120] The power reset control unit 234 of the operation unit 216 detects that the operation mode of the image forming apparatus 200 has become the standby mode by changing the image receiving signal 2022 from LOW to HIGH.

[0121] The start-up of the image forming apparatus 200 is completed by the processing from time T1 to T5, and the operation mode of the image forming apparatus 200 from time T5 to T6 is the standby mode.

[0122] At time T6, the power supply control unit 250 of the main control unit 201 transitions to the second power saving mode when it detects that no operation has been performed for a certain period of time in the standby mode or when a user inputs an instruction to transition to the power saving mode. Then, the main CPU 202 stops transmitting a display image to the LCD unit 212.

[0123] Furthermore, at time T6, the power supply control unit 250 of the main control unit 201 changes the output of the second mode notification signal 2053 from HIGH to LOW to notify the operation unit 216 that the main control unit 201 will transition to the second power saving mode.

[0124] The power reset control unit 234 of the operation unit 216 detects a transition to the second power saving mode when the output of the second mode notification signal 2053 changes from HIGH to LOW while the output of the first mode notification signal 2050 remains HIGH.

[0125] Furthermore, at time T6, when the image output unit 209 of the operation unit 216 detects that the transmission of the display image from the main CPU 202 to the LCD unit 212 has stopped, it changes the image receiving signal 2022 from HIGH to LOW, and notifies the sub CPU 208 that the transmission of the display image to the LCD unit 212 has stopped.

[0126] Furthermore, at time T6, when the power supply control unit 302 of the operation unit 216 detects that the second mode notification signal 2053 has been changed from HIGH to LOW, it changes the output of the power supply control signal 3007 from HIGH to LOW. Then, it turns off the switches 308 and 309 to cut off the supply of power supplies V4 and V5.

[0127] Furthermore, at time T6, the supply of power from power sources V4 and V5 is cut off, and the image display on the LCD unit 212 is also turned off.

[0128] The operation mode of the image forming apparatus 200 from time T6 to time T7 is the second power saving mode.

[0129] At time T7, when the power supply control unit 250 of the main control unit 201 detects that no user operation has been performed for a certain period of time in the second power saving mode, it changes the output of the first mode notification signal 2050 from HIGH to LOW, and notifies the main control unit 201 that it will transition to the first power saving mode.

[0130] Furthermore, at time T7, when the power supply control unit 302 detects that the first mode notification signal 2050 has been changed from HIGH to LOW, it changes the output of the power supply control signal 2051 from HIGH to LOW, turns off the switch 307, and cuts off the supply of power V3.

[0131] Furthermore, at time T7, when the second power supply monitoring unit 304 detects that the supply of power supply V3 has been cut off, it changes the second power supply state notification signal 3004 from HIGH to LOW, and notifies the reset control unit 306 that the supply of power supply V3 has been cut off.

[0132] Furthermore, at time T7, when the reset control unit 306 detects that the second power state notification signal 3004 has been changed from HIGH to LOW, it changes the output of the reset signal 3004 from HIGH to LOW, and puts the sub CPU 208 into a reset state.

[0133] The operation mode of the image forming apparatus 200 from time T7 to time T9 is the first power saving mode.

[0134] At time T7, image forming apparatus 200 transitions to the first power saving mode and sub CPU 208 is reset, but reset signal 3001 to touch panel control unit 210 remains in the reset release state. This allows touch panel control unit 210 to retain the setting information for detecting touch input set by sub CPU 208 during standby mode even after transition to the first power saving mode, making it possible to detect touches on touch panel 211 with appropriate settings.

[0135] At time T8, when the touch panel control unit 210 detects a touch input from the user to the touch panel 211, it changes the output of the touch detection signal 2002 from LOW to HIGH to the return signal generation unit 235. This notifies the return signal generation unit 235 that the touch panel 211 is being touched.

[0136] Furthermore, at time T8, the return signal masking unit 501 does not mask the touch detection signal 2002 because the power supply control signal 2051 is LOW, i.e., the power supply V3 is OFF, and enables the return signal 5001 after masking, outputting HIGH. The OR gate 502 enables the return signal 2033, outputs HIGH, and instructs the power supply control unit 250 of the main control unit 201 to return to standby mode. On the other hand, the return signal 2052 output by the sub CPU 208 is disabled because the power supply V3 of the sub CPU 208 is OFF.

[0137] At time T9, the power supply control unit 250 of the main control unit 201 detects that the return signal 2033 from the operation unit 216 has been enabled and set to HIGH. Then, the power supply control unit 250 outputs the first mode notification signal 2050 as a HIGH output, notifying the operation unit 216 of the intention to return to the standby mode.

[0138] Furthermore, at time T9, when the power supply control unit 302 of the operation unit 216 detects that the mode notification signal 2050 has been set to HIGH, it sets the output of the power supply control signal 2051 to HIGH, turns on the switch 307, and starts supplying the power supply V3.

[0139] Furthermore, at time T9, when the second power supply monitor 304 detects that the supply of the power supply V3 has started, it changes the output of the second power supply rising edge notification signal 3005 from LOW to HIGH, and notifies the reset control unit 306 that the supply of the power supply V3 has started. Furthermore, at time T9, the first reset generation unit 401 of the reset control unit 306 detects that the second power supply rising edge notification signal 3005 has been set to HIGH. Then, it changes the reset signal 3001 from HIGH to LOW, and temporarily resets the touch panel control unit 210.

[0140] Furthermore, at time T9, the power supply control signal 2051 becomes HIGH, that is, the power supply V3 becomes ON, so the return signal generating unit 235 masks the touch detection signal 2002 and changes the return signal 2033 to LOW, thereby outputting it as disabled.

[0141] At time T10, the touch panel control unit 210 detects that the touch input from the user to the touch panel 211 has been released, and notifies the return signal generating unit 235 that the touch panel 211 is no longer being touched. Specifically, the touch panel control unit 210 notifies the return signal generating unit 235 by changing the touch detection signal 2002 from HIGH to LOW.

[0142] At time T11, when the second power supply monitor 304 detects that the power supply V3 has started to be supplied stably, it changes the output of the second power supply state notification signal 3004 from LOW to HIGH, and further changes the second power supply rising edge notification signal 3005 from HIGH to LOW to notify the reset control unit 306 that the power supply V3 has started to be supplied stably.

[0143] Furthermore, at time T11, first reset signal generation unit 401 of reset control unit 306 detects that second power rising edge notification signal 3005 has changed from HIGH to LOW, and again changes the output of reset signal 3001 to touch panel control unit 210 from LOW to HIGH, releasing touch panel control unit 210 from the reset state.

[0144] Furthermore, at time T11, the second reset signal generating section 402 of the reset control section 306 changes the output of the reset signal 3002 from LOW to HIGH, releasing the sub CPU 208 from the reset state.

[0145] In the first power mode, the touch panel control unit (slave device) operates in the absence of the sub CPU (master device), which may cause a deviation in the setting values and correction values for touch panel control. With the above configuration, when transitioning from the first power mode to the standby mode, not only is the sub CPU 208 reset, but it is also possible to reset the touch panel control unit 210. Therefore, even if the setting values and correction values are deviated in the first power mode, they can be returned to normal, making it possible to continue normal operation.

[0146] At time T12, the power supply control unit 250 of the main control unit 201 changes the output of the second mode notification signal 2053 from LOW to HIGH, notifying that the start-up process of the main control unit 201 has been completed and that the mode has shifted to the standby mode.

[0147] Furthermore, at time T12, when the power supply control unit 302 detects that the second mode notification signal 2053 has been changed from LOW to HIGH, it changes the power supply control signal 3007 from LOW to HIGH, thereby turning on the switches 308 and 309 and starting the supply of power supplies V4 and V5.

[0148] At time T12, the image output unit 209 starts displaying the display image received from the main CPU 202 on the LCD unit 212 as a result of the start of supply of power from the power sources V4 and V5.

[0149] The process from time T9 to time T12 completes the process of returning image forming apparatus 200 from the first power saving mode to the standby mode. However, reset signal 3001 to touch panel control unit 210 goes into a reset state once a rising edge of power supply V3 of sub CPU 208 is detected. When power supply V3 starts to be supplied stably, reset signal 3001 to touch panel control unit 210 and reset signal 3002 to sub CPU 208 go into a reset release state at the same time.

[0150] As a result, even if the setting information or correction information for detecting touch input held in the first power saving mode becomes misaligned, touch detection becomes possible by resetting the touch panel control unit 210 once. In other words, the reset causes the sub CPU 208 to set the touch input detection setting again, so that touch detection on the touch panel 211 becomes possible with the appropriate setting even after returning to the standby mode.

[0151] The operation mode of the image forming apparatus 200 from time T12 to T13 is the standby mode.

[0152] At time T13, when the power switch (not shown) is turned off by a user operation, first the main control unit 201 starts a shutdown process of the image forming apparatus 200. Then, the main CPU 202 stops sending a display image to the LCD unit 212 of the operation unit 216.

[0153] Furthermore, at time T13, when the image output unit 209 of the operation unit 216 detects that the transmission of the display image from the main CPU 202 to the LCD unit 212 has been stopped, it changes the image receiving signal 2022 from HIGH to LOW and notifies the sub CPU 208 that the transmission of the display image to the LCD unit 212 has been stopped.

[0154] At time T14, the power supply control unit 250 of the main control unit 201 simultaneously changes the first mode notification signal 2050 and the second mode notification signal 2053 from IGH to LOW, thereby notifying the operation unit 216 that the main control unit 201 is performing a shutdown process.

[0155] Furthermore, at time T14, when the power supply control unit 302 of the operation unit 216 detects that the second mode notification signal 2053 has been changed from HIGH to LOW, it changes the output of the power supply control signal 3007 from HIGH to LOW, thereby turning off the switches 308 and 309 and cutting off the supply of power supplies V4 and V5.

[0156] Furthermore, at time T14, the supply of power from power sources V4 and V5 is cut off, and the image display on the LCD unit 212 is also turned off.

[0157] Furthermore, at time T14, when the power supply control unit 302 of the operation unit 216 detects that the mode notification signal 2050 has been changed from HIGH to LOW, it changes the output of the power supply control signal 2051 from HIGH to LOW, turns off the switch 307, and cuts off the supply of power V3.

[0158] Furthermore, at time T14, when the second power supply monitoring unit 304 detects that the supply of power supply V3 has been cut off, it changes the second power supply state notification signal 3004 from HIGH to LOW, and notifies the reset control unit 306 that the supply of power supply V3 has been cut off.

[0159] Furthermore, at time T14, when the reset control unit 306 detects that the second power state notification signal 3004 has been changed from HIGH to LOW, it changes the output of the reset signal 3004 from HIGH to LOW, and puts the sub CPU 208 into a reset state.

[0160] At time T15, first, the power supply control unit 250 of the main control unit 201 cuts off the supply of the power supply V1, and further, the supply of the power supply V2 converted by the power supply conversion unit 301 of the operation unit 216 is also turned off.

[0161] The shutdown process of the image output unit 209 is completed by the processes from T13 to T15.

[0162] Fig. 7 is a timing chart showing an example of the behavior of the internal signals of the power reset generation unit 234 and the main power / signals input / output. Fig. 6 is a timing chart showing a transition to the second power saving mode, then to the first power saving mode, and then to a return to the standby mode. On the other hand, Fig. 7 is a timing chart showing a transition to the second power saving mode and then to a return to the standby mode, which is a difference between the two.

[0163] 6. The difference from FIG. 6 is the section from time T6 to T12, and times T1 to T6 and T12 to T15 are the same as in FIG.

[0164] The period from time T5 to time T6 in FIG. 7 is the same as in FIG. 6, so the description will be omitted.

[0165] At time T16, the touch panel control unit 210 detects that the user has performed a touch input on the touch panel 211. Then, the touch panel control unit 210 changes the output of the touch detection signal 2002 from LOW to HIGH to notify the sub CPU 208 and the return signal generation unit 235 that a touch has occurred.

[0166] Furthermore, at time T16, since the power control signal 2051 is HIGH, that is, the power supply V3 is ON, the return signal masking unit 501 of the return signal generating unit 235 masks the touch detection signal 2002. As a result, the post-masking return signal 5001 is disabled and outputs LOW.

[0167] Furthermore, at time T16, when the sub CPU 208 detects that the touch detection signal 2002 from the touch panel control unit 210 has changed from LOW to HIGH during the second power saving mode, it enables the return signal 2052 and outputs HIGH.

[0168] The power reset control unit 234 of the operation unit 216 detects a transition to the second power saving mode when the output of the second mode notification signal 2053 changes from HIGH to LOW while the output of the first mode notification signal 2050 remains HIGH.

[0169] Furthermore, at time T16, since the recovery signal 2052 is enabled and in a HIGH state, the OR gate 502 of the recovery signal generating unit 235 enables the recovery signal 2033 and outputs a HIGH signal.

[0170] At time T17, the sub CPU 208 disables the return signal 2052 for a certain period of time, and further the return signal generating unit 235 disables the return signal 2033 and outputs LOW.

[0171] At time T18, when the touch panel control unit 210 detects that the touch input from the user to the touch panel 211 has been released, it notifies the touch panel 211 that it is no longer being touched. Specifically, it changes the touch detection signal 2002 from HIGH to LOW to the return signal generating unit 235.

[0172] The process from time T12 onwards is the same as in FIG. 6, and therefore the description will be omitted.

[0173] In FIG. 7, the return signal 2033 is generated by a signal output by the sub CPU 208 in order to return from the state in which the sub CPU 208 is operating in the second power saving mode to the standby mode.

[0174] On the other hand, in FIG. 6, in order for the sub-CPU 208 in the first power saving mode to return to the standby mode from a non-operating state, the return signal 2033 is generated by a signal output by the return signal mask unit 501 in the return signal generation unit 235.

[0175] As described above, in the image forming apparatus 200 of this embodiment, the power reset control unit 234 controls the power OFF / ON for each device in the operation unit 216 based on the output state of the mode notification signal from the main control unit 201. In this way, the power control of the entire operation unit 216 is performed.

[0176] As a result, in the first power saving mode, devices to which power is supplied within the operation unit are limited to the touch panel 211, touch panel control unit 210, return signal generation unit 235, and power reset control unit 234. On the other hand, in the first power saving mode, it is possible to return from the first power saving mode to the standby mode by touching the touch panel.

[0177] This also makes it possible to reduce power consumption compared to the second power saving mode / standby mode.

[0178] In the second power saving mode, power is also supplied to the sub CPU 208, and the sub CPU 208 is in an operable state. Since the touch panel control unit 210 is also in a state in which it is possible to acquire the coordinates of a touch, it is possible to return to the standby mode by a return factor other than the detection of a touch on the touch panel. The return factor other than the touch detection may be, for example, returning to the standby mode only when a specific area is touched, or returning to the standby mode when a human is detected by a human sensor (not shown).

[0179] In this way, the control of returning to the standby mode may be changed between the first power saving mode and the second power saving mode, or the return from the first power saving mode and the second power saving mode may be realized in common by only a control signal from the return signal generating unit 235.

[0180] Furthermore, in the image forming apparatus 200 of this embodiment, the power reset control unit 234 in the operation unit 216 performs reset control based on the output state of the mode notification signal from the main control unit 201 .

[0181] As a result, when image forming apparatus 200 transitions to the first power saving mode, reset signal 3001 to touch panel control unit 210 remains in the reset release state. Therefore, touch panel control unit 210 retains the setting information for detecting touch input set by sub-CPU 208 in the standby mode, and touch detection on touch panel 211 becomes possible with appropriate settings.

[0182] Furthermore, when image forming apparatus 200 transitions from the first power saving mode to the standby mode, reset signal 3001 to touch panel control unit 210 is reset once upon detecting the rising edge of power supply V3 of sub CPU 208. Then, when power supply V3 starts to be supplied stably, reset signal 3001 to touch panel control unit 210 and reset signal 3002 to sub CPU 208 are simultaneously released from the reset state.

[0183] This enables the touch panel control unit 210 to detect touches on the touch panel 211 with appropriate settings even if the setting information or correction information for detecting touch input held in the first power saving mode has become misaligned.

[0184] Example 2 Next, a second embodiment will be described with reference to the drawings. Note that the description of the configuration diagram and the flow chart described in the first embodiment will be omitted.

[0185] The differences between the second embodiment and the first embodiment are in FIG. 3, FIG. 4, and FIG.

[0186] In the first embodiment, when transitioning from the first power saving mode to the standby mode, the reset signal 3001 to the touch panel control unit 210 is reset once upon detection of a rising edge of the power supply V3 of the sub CPU 208. Then, when the power supply V3 starts to be supplied stably, the reset signal 3001 to the touch panel control unit 210 and the reset signal 3002 to the sub CPU 208 are simultaneously released from the reset state.

[0187] In the second embodiment, when the first power saving mode is switched to the standby mode, the power supply control unit 302 notifies the sub CPU 208 of the return from the first power saving mode. Therefore, the sub CPU 208 is different from the first embodiment in that it applies a software reset to the touch panel control unit 210 via a control signal 2003.

[0188] First, the only difference between the second embodiment and the first embodiment in FIG. 3 and FIG. 4 is that there is no second power rising edge notification signal 3005. Since the rest is the same, a description thereof will be omitted.

[0189] Next, the second embodiment will be described with reference to the timing chart of FIG. 8 instead of FIG.

[0190] The differences between FIG. 6 and FIG. 8 are times T3, T4, T9, and T11, and the rest are the same as in FIG. 6, so the description will be omitted.

[0191] The period from time T1 to T2 is the same as in FIG. 6, so a description thereof will be omitted.

[0192] At time T19, first, the power supply control unit 250 of the main control unit 201 changes the outputs of the first mode notification signal 2050 and the second mode notification signal 2053 from LOW to HIGH, thereby notifying the operation unit 216 that the main control unit 201 is starting up.

[0193] Furthermore, at time T19, when the power supply control unit 302 detects that the first mode notification signal 2050 has been changed from LOW to HIGH, it changes the power supply control signal 2051 from LOW to HIGH to turn on the switch 307, thereby starting the supply of power V3.

[0194] Furthermore, at time T19, the power supply control unit 302 detects that the second mode notification signal 2053 has been changed from LOW to HIGH. Then, in order to turn on the switches 308 and 309, the power supply control signal 3007 is changed from LOW to HIGH, and the supply of power supplies V4 and V5 is started.

[0195] At time T20, when the second power supply monitor 304 detects that the power supply V3 has started to be supplied stably, it changes the output of the second power supply state notification signal 3004 from LOW to HIGH, and notifies the reset control unit 306 that the power supply V3 has started to be supplied stably. Furthermore, at time T20, the second reset signal generator 402 of the reset control unit 306 changes the reset signal 3002 to the sub CPU 208 from HIGH to LOW, and releases it from the reset state.

[0196] The period from time T5 to T8 is the same as in FIG. 6, so a description thereof will be omitted.

[0197] At time T21, the power supply control unit 250 of the main control unit 201 detects that the return signal 2033 from the operation unit 216 has been enabled and set to HIGH. Then, the power supply control unit 250 changes the mode notification signal 2050 from LOW to HIGH to notify the operation unit 216 of the intention to return to the standby mode.

[0198] Furthermore, at time T21, when the power supply control unit 302 of the operation unit 216 detects that the mode notification signal 2050 has been set to HIGH, it sets the output of the power supply control signal 2051 to HIGH, turns on the switch 307, and starts supplying power V3.

[0199] Furthermore, at time T21, the power supply control signal 2051 is HIGH, that is, the power supply V3 is turned ON, so the return signal generating unit 235 masks the touch detection signal 2002 and changes the return signal 2033 to LOW, thereby outputting it as disabled.

[0200] At time T10, the situation is the same as in FIG. 6, so a description thereof will be omitted.

[0201] At time T22, when the second power supply monitoring unit 304 detects that the power supply V3 has begun to be supplied stably, it changes the output of the second power supply state notification signal 3004 from LOW to HIGH, and notifies the reset control unit 306 that the power supply V3 has begun to be supplied stably.

[0202] Furthermore, at time T22, the second reset signal generating section 402 of the reset control section 306 changes the output of the reset signal 3002 from LOW to HIGH, releasing the sub CPU 208 from the reset state.

[0203] Furthermore, at time T22, the sub CPU 208 is released from reset and transmits a READY signal 2031 to the main CPU 202 to notify that the sub CPU 208 is in an operable state (a state in which the sub CPU 208 can receive the communication signal 2010).

[0204] Thereafter, the main CPU 202 notifies the sub CPU 208 via a communication signal 2010 that the sub CPU 208 has returned from the first power saving mode.

[0205] When a notification is received from main CPU 202 indicating that the first power saving mode has been returned to, an additional software reset is applied to touch panel control unit 210 via control signal 2003. Furthermore, setting information for appropriately detecting touch input, such as correcting the touch sensitivity of touch panel 211 and touch coordinate deviation, is transmitted to touch panel control unit 210.

[0206] The process from time T12 onwards is the same as in FIG. 6, so a description thereof will be omitted.

[0207] As described above, in image forming apparatus 200 of the present embodiment, when the mode transitions from the first power saving mode to the standby mode, sub-CPU 208 performs a software reset on touch panel control unit 210.

[0208] This enables the touch panel control unit 210 to detect touches on the touch panel 211 with appropriate settings even if the setting information or correction information for detecting touch input held in the first power saving mode has become misaligned.

[0209] <Other embodiments> This embodiment can also be realized by supplying a program that realizes one or more of the functions of the above-mentioned embodiment to a system or device via a network or a storage medium, and having one or more processors in the computer of the system or device read and execute the program. It can also be realized by a circuit (e.g., ASIC) that realizes one or more of the functions.

Claims

1. There is an information processing device, An operation receiving means for receiving an operation from a user; A control unit that receives a signal from the operation reception means; a generation unit that receives a signal from the operation reception means and generates a return signal; a power control means for transitioning a power state of the information processing device from a first power state in which no power is supplied to the control unit to a second power state in which power is supplied to the control unit based on the recovery signal; having In the second power state, the generation unit does not generate the return signal even when a signal is received from the operation reception means, and in the first power state, the generation unit generates the return signal when a signal is received from the operation reception means.

23. An information processing apparatus comprising:

2. In the second power state, when the generating unit receives a signal from the operation receiving unit, the generating unit generates a disable signal, thereby not generating the return signal.