JP2004243533A - Image forming apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an image forming apparatus constituted so as to save the energy of a network device. <P>SOLUTION: A clock of 125 MHz is usually supplied to an MAC 104 from an oscillator 101. At the time of transfer to an energy saving mode, the AND gate 105 provided between the oscillator 101 and the MAC 104 is controlled by the clock stopping signal 106 from the MCA 104 to stop the supply of the clock of 125 MHz to the MAC 104 from the oscillator 101. Further, the MAC 104 is connected to a network through a PHY 103 and a network connector 107 and connected to the network device not shown in Fig. through the hub 303 on the network. A clock of 25 MHz is supplied to the PHY 103 from an oscillator 102. The MAC 104 leads the register of the PHY 103, when MAC enters the energy saving mode, to lower an operation clock to 2.5 MHz or to hold operation of 25 MHz by the connectable mode of the hub or repeater of a connection partner. <P>COPYRIGHT: (C)2004,JPO&NCIPI

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to an image forming apparatus, and more particularly, to an image forming apparatus incorporating a plurality of functions such as copying, facsimile, printing, and scanning, and used in a complex system connected to a network such as Ethernet (registered trademark).
[0002]
[Prior art]
In recent years, complex systems incorporating a plurality of functions such as copying, faxing, printing, and scanning have been frequently used. This kind of complex system usually shifts to standby mode, preheat mode, low power mode, sleep mode, and in order to save energy after a certain period of time without using after turning on the power. Is controlled.
[0003]
When the above-described complex system is in the energy saving standby state, when the power button provided on the operation panel is pressed, paper is set on the ADF, or the press plate is operated in order to use the system. , So that all of the functions of the system are restored.
[0004]
As described above, for example, the techniques described in Patent Literatures 1 to 5 are known as conventional techniques related to energy saving control.
[0005]
[Patent Document 1]
JP 2001-22481 A
[Patent Document 2]
JP 2001-191616 A
[Patent Document 3]
JP-A-2002-44309
[Patent Document 4]
JP-A-2002-52784
[Patent Document 5]
JP-A-11-126000
[Problems to be solved by the invention]
As described above, in the complex system according to the related art, no consideration is given to shifting to the energy saving standby state for the network device provided when the network device is used by being connected to the network, and the network device is always controlled to operate normally. However, even when the system enters the energy saving standby state, there is a problem that the power consumption of the network device is large.
[0011]
SUMMARY OF THE INVENTION An object of the present invention is to provide an image forming apparatus that solves the above-described problems of the conventional technology and enables energy saving of network devices.
[0012]
[Means for Solving the Problems]
A first means of the present invention for achieving the above object is to stop an operation clock for a Gigabit Ethernet-compatible device during an energy saving standby in an image forming apparatus which can be in an energy saving standby state and has a network function. It is characterized by having a means for making it.
[0013]
According to a second aspect of the present invention, in an image forming apparatus which can be in an energy saving standby state and has a network function, a PHY is accessed during an energy saving standby to select a mode with a low operating frequency and supply a clock. It is characterized by comprising means for performing.
[0014]
According to a third aspect of the present invention, in an image forming apparatus having a network function capable of being in an energy saving standby state and having a network function, a means for stopping an operation clock for a Gigabit Ethernet compatible device during energy saving standby, Means for accessing the PHY to select a mode with a low operating frequency and supply a clock.
[0015]
According to a fourth aspect of the present invention, in the first or the third aspect, upon returning from the energy saving standby state, the network function is switched to the Giga Ethernet mode by receiving a network start condition frame added before data. It is characterized by comprising means for returning.
[0016]
According to a fifth aspect of the present invention, in the second or the third aspect, at the time of return from the energy saving standby state, the PHY is provided with means for accessing the PHY, performing auto negotiation and enabling data transmission / reception at an optimum speed. Features.
[0017]
According to a sixth aspect of the present invention, in the third aspect, when returning from the energy saving standby state, the network function is returned to the Giga Ethernet mode by receiving a network start condition frame added before data. And means for accessing the PHY to perform auto-negotiation and transmit and receive data at an optimum speed.
[0018]
According to the above-described first means of the present invention, the clock for Giga Ethernet having a high operating frequency can be stopped during the energy saving standby, so that the power consumption can be suppressed.
[0019]
Further, according to the above-described second means of the present invention, a clock having a low operating frequency can be selected instead of a clock for Giga Ethernet, so that power consumption can be suppressed.
[0020]
Further, according to the third means of the present invention, the clock for Giga Ethernet having a high operation frequency can be stopped and the clock having a low operation frequency can be selected during the energy saving standby. More power consumption can be suppressed as compared with the second means.
[0021]
Further, according to the fourth means of the present invention described above, upon returning from the energy saving standby state in the first or third means, the network activation condition frame added before the data is received, and the network activation condition frame is received. Since the function can be returned to the giga Ethernet mode, the system can be restored at any time via the network.
[0022]
Further, according to the fifth means of the present invention described above, when returning from the energy saving standby state in the second or third means, the PHY is auto-negotiated, thereby returning the system to the original operating frequency. Can be achieved.
[0023]
Further, according to the sixth means of the present invention described above, when returning from the energy saving standby state by the third means, the network function is transmitted to the network by receiving the network start condition frame added before the data. The system can be returned to the Ethernet mode, and by performing auto-negotiation of the PHY, the system can be returned to its original operating frequency.
[0024]
BEST MODE FOR CARRYING OUT THE INVENTION
FIG. 6 is a block diagram showing a configuration of a hardware platform of the image forming apparatus that executes the energy saving control according to the present invention.
[0025]
The image forming apparatus illustrated in FIG. 6 is configured by connecting a controller 602 and an engine unit 603 by PCI, and further includes a power supply unit (PSU) 610. The controller 602 is a controller that controls the entire image forming apparatus, drawing, communication, and input from an operation unit. The engine unit 603 has a scanner 608 and a plotter 609. The plotter 609 is a black and white plotter, a one-drum color plotter, and the scanner 608 is a scanner, a fax unit, and the like. The engine unit 603 includes an image processing unit 622 that performs image processing such as error diffusion and gamma conversion, an ASIC 607 including a PCI unit 623, and a CPU 611, in addition to so-called engine units such as a plotter 609 and a scanner 608. are doing.
[0026]
The controller 602 includes a CPU 605, a north bridge (NB) 604, a system memory (MEM-P) 612, a south bridge (SB) 621, a local memory (MEM-C) 619, an ASIC 618, and an operation unit 616. , A plurality of hard disk drives (HDD) 617, an ASIC 620, OPTIONs 614 and 615, and a ROM 613. The north bridge (NB) 604 and the ASIC 618 are connected by an AGP (Accessed Graphics Port). . The NB 604 and the SB 621 are connected by a PCI.
[0027]
The CPU 605 controls the entire image forming apparatus, and has a chip set including the NB 604, the MEM-P 612, the ASIC 620, the options 614 and 615, the ROM 613, and the SB 621. Here, the interface of the CPU 605 is not disclosed, and it is assumed that other devices are connected via a chipset.
[0028]
The NB 604 is a bridge for connecting the CPU 605 to the MEM-P 612, the SB 621, and the AGP, and the MEM-P 612 is a system memory used as a drawing memory or the like of the image forming apparatus. The SB 621 is a bridge for connecting the NB 604 to the ROM 613, a PCI device, and peripheral devices. The options 614 and 615 are empty slots for connecting optional PCI devices and peripheral devices.
[0029]
The MEM-C619 is a local memory used as an image buffer for copying and a code buffer, and the ASIC 618 is an IC for image processing having a hardware element for image processing, and includes AGP, PCI, HDD 617, and MEM-C619. It also has a role of a bridge for connecting each.
[0030]
An operation unit 616 is an operation unit that receives an input operation from a user and performs display for the user. An HDD 617 is a storage for storing image data, storing programs, storing font data, and storing forms. It is.
[0031]
The AGP that connects the ASIC 618 and the NB 604 is a bus interface for a graphics accelerator card proposed to speed up graphics processing, and directly accesses the system memory 612 at a high throughput to provide a graphics accelerator card. Is to speed up.
[0032]
The AGP is originally used when a 3D (three-dimensional) image is smoothly displayed on a display. In the image forming apparatus shown in FIG. 6, the NB 604 and the ASIC 618 are connected via the AGP. I have.
[0033]
That is, as described above, since the interface of the CPU 605 is not disclosed, the ASIC 618 is connected via the NB 604 which is a part of the chip set. At this time, if the both are connected by using the PCI bus, the performance is reduced. Therefore, the AGP is extended and used here.
[0034]
The ASIC 118 includes an editing unit, a video output unit, a synthesizing unit, and the like. The ASIC 118 edits image data in a desired state and outputs the edited data to the engine unit 603. Since it is not a summary, the description is omitted.
[0035]
The ASIC 620 includes a MAC (Media Access Control) 601 that performs data conversion, data exchange with a network, and the like. The illustrated image forming apparatus is connected to an external device via the MAC 601.
[0036]
In the image forming apparatus as described above, some power saving measures such as turning off the power of the engine portion when not in use are taken, but the power saving measures of the MAC 601 are generally not taken.
[0037]
FIG. 1 is a block diagram showing a configuration of an embodiment of the present invention in a physical layer and a data link layer of Giga Ethernet connected to the MAC 601 described above, and FIG. 2 illustrates a clock stop processing operation at the time of transition to energy saving. FIG. 3 is a diagram illustrating a configuration example of a link destination of the PHY, FIG. 4 is a flowchart illustrating a processing operation at the time of returning from the energy saving standby state, and FIG. 5 is a diagram illustrating the contents of the Auto-Negotiation Link Partner Availability register of the PHY. FIG.
[0038]
As shown in FIG. 1, a MAC 104 (same as the MAC 601 described in FIG. 6) is usually supplied with a clock of 125 MHz used in the giga Ethernet from the oscillator 101. An AND gate 105 is provided between the MAC 104 and the MAC 104, and the supply of the 125 MHz clock to the MAC 104 from the oscillator 101 can be stopped by controlling the AND gate 105 by a clock stop signal 106 from the MCA 104.
[0039]
Further, as shown in FIG. 3, the MAC 104 is connected to the network via a PHY 103 having a function of performing signal conversion between the MAC 104 and the network to transfer data, and a network connector 107. Can be connected to a network device (not shown) via a hub 303 installed on the network. The PHY 103 is supplied with a 25 MHz clock from the oscillator 102.
[0040]
Normally, data transmission over a network such as Ethernet connected via the network connector 107 is performed at any one of 10 MHz, 100 MHz, and 1 GHz. The PHY 103 has a different clock supply method depending on its specifications. However, the PHY 103 used in the embodiment of the present invention is capable of receiving data from the connector 107 at any speed of 10 MHz, 100 MHz, and 1 GHz. , MAC 104 are supplied with 2.5 MHz, 25 MHz, and 125 MHz clocks. Further, only in the case of transmission at 1 GHz from the MAC 104, the 125 MHz clock from the oscillator 101 is supplied to the MAC 104. Further, in the case of transmission at 10 MHz and 100 MHz, a clock of 2.5 MHz and 25 MHz is supplied from the PHY 103 to the MAC 104.
[0041]
As described above, the operation clock used in Giga Ethernet is 125 MHz. However, the higher the frequency, the higher the power consumption. If the 125 MHz clock is continuously supplied during the energy saving standby state in the system standby state, extra power is consumed during energy saving. In the embodiment of the present invention, conventionally, the operating frequency of the MAC and the PHY has not been changed even in the energy saving standby state, whereas in the energy saving standby state, the operation clock is stopped or reduced, and We are trying to save energy.
[0042]
Next, with reference to the flow shown in FIG. 2, the processing operation of the clock stop at the time of the transition to the energy saving will be described. The clock stopped here is a clock supplied from the oscillator 101 shown in FIG.
[0043]
(1) When the MAC 104 detects an energy-saving condition detection signal that is asserted when the MAC enters the energy-saving mode, the MAC 104 reads the register of the PHY 103 and reads the connectable mode of the hub or repeater to be connected. As shown in FIG. 3, the connection destination hub 303 is connected to the PHY 103 via the network connector (RJ-45) 107, and the operation mode of the hub 303 is set by the register of the PHY 103. You can check. FIG. 5 shows the status of the link destination of the Auto-Negotiation Link Partner Availability register of the PHY 103. The MAC 104 can know the transfer capability of the hub 303 by reading this register of the PHY 103 (steps 201 and 202).
[0044]
As shown in FIG. 5, the registers of the PHY can assert 100BASE-T4, 100BASE-TX Full Duplex, 100BASE-TX, 10BASE-T Full Duplex, and 10BASE-T statuses as statuses 501 to 505. Is stored.
[0045]
(2) The MAC 104 determines whether or not operation at 10 BASE is possible based on the status of the read register (step 203).
[0046]
(3) If all of the statuses 501 to 505 in the register are asserted in the determination in step 203, operation at 10 BASE is possible. Therefore, the operation mode is set to 10 BASE and the operation clock is set to 2.5 MHz. The mode is set to the energy saving mode (step 204).
[0047]
(4) If the asserted status in the register is only one of the statuses 501, 502, and 503 in the determination in step 203, the operation mode is set to 100BASE, the operation clock is set to 25 MHz, and the energy saving mode is set ( Step 205).
[0048]
(5) After the processing of step 204 or step 205, the MAC 104 transmits the clock stop signal 105 to control the AND gate 105, thereby stopping the supply of the 125 MHz clock from the oscillator 101 to the MAC 104. , And asserts the energy-saving mode signal. This energy saving mode signal is equivalent to the clock stop signal 106 shown in FIG. 1 (steps 206 and 207).
[0049]
According to the above-described processing, in the energy saving mode of the system, it is possible to achieve energy saving according to the status of the network device connected to the function unit for connection to the network.
[0050]
In the embodiment of the present invention, even if the supply of the 125 MHz clock to the MAC 104 is simply stopped in the above-described processing, the minimum necessary number of the clocks may be determined according to the status stored in the PHY register. The clock may simply be used.
[0051]
Next, the processing operation at the time of returning from the energy saving standby state will be described with reference to the flow shown in FIG.
[0052]
(1) Upon receiving a frame via the PHY 103, the MAC 104 determines whether or not the frame is an activation frame. If the frame is another frame that is not an activation frame, the MAC 104 repeats the processing up to this point (step 401, 402).
[0053]
(2) If it is determined in step 402 that the received frame is a start frame, the clock stop signal 106 is deasserted and a 125 MHz clock for gigabiter is supplied from the oscillator 101 to the MAC 104 (step 403).
[0054]
(3) Then, the MAC 104 accesses the register of the PHY 103, sets the auto-negotiation function to ON, and enables normal transmission / reception (step 404).
[0055]
According to the above-described processing, the system can be returned from the energy saving standby state by the start frame from the connected network device.
[0056]
Next, the auto-negotiation function and the activation frame in the description of the above-described return processing will be described.
[0057]
* Auto negotiation function At present, the Ethernet uses a mixture of three transfer speeds of 10 BASE: 10 Mb / sec, 100 BASE: 100 Mb / sec, and 1000 BASE: 1000 Mb / sec. The reason for this is that the speed that can be supported varies depending on the performance of a NIC (Network Interface Card), the capabilities of a repeater, a hub, and the like. Further, it is necessary to select between full-duplex communication and half-duplex communication. Full-duplex communication is a communication method in which transmission and reception can be handled simultaneously by performing communication in a one-to-one relationship between a sender and a receiver. In addition, half-duplex communication is a communication method in which transmission and reception cannot be performed simultaneously because a transmission path is supplied in domain units. The above-described selection of the speed usually selects the PHY 103 so that the PHY 103 can automatically access it in the fastest state without any need of the user. This function is called an auto negotiation function. Originally, PHY is set to auto-negotiation by default, so if you want to forcibly drop the transfer mode, or if you want to set only full-duplex communication or only half-duplex communication, etc. Needs to be changed.
[0058]
* In the startup frame network, there is a function to return from the energy saving standby state by transmitting a specific frame when the device is in the energy saving mode. The specific frame is called an activation frame, and by registering the activation frame in the MAC, the user can activate the device via a network or the like at an arbitrary time.
[0059]
【The invention's effect】
According to the embodiments of the present invention described above, it is possible to provide an image forming apparatus capable of saving energy of a network device.
[Brief description of the drawings]
FIG. 1 is a block diagram showing a configuration of an embodiment of the present invention in a physical layer and a data link layer of Giga Ethernet connected to a MAC.
FIG. 2 is a flowchart illustrating a clock stop processing operation at the time of transition to energy saving.
FIG. 3 is a diagram illustrating a configuration example of a PHY link destination;
FIG. 4 is a flowchart illustrating a processing operation when returning from an energy saving standby state.
FIG. 5 is a diagram illustrating the contents of an Auto-Negotiation Link Partner Availability register of the PHY.
FIG. 6 is a block diagram illustrating a configuration of a hardware platform of an image forming apparatus that performs energy saving control according to the present invention.
[Explanation of symbols]
101, 102 Oscillator 103 PHY
104, 601 MAC (Media Access Control)
105 AND gate 107 Network gate 303 Hub 602 Controller 603 Engine 607, 620 ASIC

Claims (6)

An image forming apparatus which can be in an energy saving standby state and has a network function, comprising: means for stopping an operation clock for a gigabit Ethernet-compatible device during energy saving standby. An image forming apparatus which can be in an energy saving standby state and has a network function is provided with means for accessing a PHY during energy saving standby, selecting a mode with a low operating frequency, and supplying a clock. Image forming device. In an image forming apparatus capable of taking a standby state for energy saving and equipped with a network function, means for stopping an operation clock for a Gigabit Ethernet-compatible device during standby for energy saving, and access to a PHY during standby for energy saving to reduce the operating frequency. Means for selecting a mode and supplying a clock. 4. The image according to claim 1, further comprising a unit for returning the network function to the Giga Ethernet mode by receiving a network start condition frame added before data when returning from the energy saving standby state. Forming equipment. 4. The image forming apparatus according to claim 2, further comprising means for accessing a PHY, performing auto negotiation, and enabling data transmission and reception at an optimum speed when returning from the energy saving standby state. Upon return from the energy saving standby state, a means for returning the network function to the Giga Ethernet mode by receiving the network start condition frame added before the data, and access to the PHY to perform auto negotiation and at an optimum speed. 4. The image forming apparatus according to claim 3, further comprising: means for enabling data transmission and reception.

Images