JP7009866B2 - Electronic devices, communication processing methods and programs - Google Patents

Description

The present invention relates to electronic devices, communication processing methods, programs, and the like.

USB (Universal Serial Bus) is known as a standard for high-speed communication between a host device and a peripheral device via a serial communication bus. For example, in USB3.0, in addition to the conventional HS (High Speed) mode of USB2.0, an SS (Super Speed) mode capable of high-speed communication at 5 Gbps is prepared. As a conventional technique of a peripheral device that realizes such communication in SS mode of USB3.0, there is a technique disclosed in Patent Document 1. In Patent Document 1, an SS processing unit having a USB3.0 SS protocol circuit and the like and a Non-SS processing unit having a USB2.0 protocol circuit and the like are provided in the peripheral device. Then, the processing in which the host device controls the SS processing unit and the Non-SS processing unit of the peripheral device so as to be in a low power state is disclosed. Specifically, the SS processing unit is controlled so as to be in a low power state of U1, U2 or U3 defined by the USB3.0 standard. The Non-SS processing unit is controlled so as to be in a low power state of L1 (sleep) or L2 (suspend) defined by the USB 2.0 standard.

Japanese Unexamined Patent Publication No. 2014-21821

When the USB communication bus is set to the power saving state, it is first necessary to restore the power saving state to the non-power saving state at the time of USB communication. Therefore, there is a problem that the return period becomes a time loss and the start of USB communication is delayed. Further, depending on the host device, a power saving transition request may be made every time a command is issued, and there is also a problem that the processing load of the electronic device that processes the power saving transition request becomes excessive. On the other hand, in a communication system using USB, it is necessary to realize power saving.

According to some aspects of the present invention, it is possible to provide an electronic device, a communication processing method, a program, and the like that can realize power saving while realizing high speed of USB communication and job execution.

One aspect of the present invention includes a communication unit that communicates via a USB communication bus and a processing unit that controls the communication unit, and the processing unit is from a host device connected to the communication bus. If the power saving transition condition is satisfied when the power saving transition request is received, the power saving transition request is permitted, the communication bus is shifted to the power saving state, and the power saving transition condition is satisfied. If not, it relates to an electronic device that rejects the power saving transition request and does not shift the communication bus to the power saving state.

According to one aspect of the present invention, when the power saving transition condition is satisfied, the power saving transition request from the host device is permitted and the power saving state is entered, so that the power saving can be realized. On the other hand, if the power saving transition condition is not satisfied, the power saving transition request from the host device is rejected, so that it is possible to prevent the recovery time from becoming a time loss and delaying the command execution. Will be. Therefore, it is possible to provide an electronic device or the like that can realize both high-speed USB communication and job execution and power saving.

Further, in one aspect of the present invention, when the state of the electronic device is the first state, the processing unit determines that the power saving transition condition is satisfied, and the state of the electronic device is the second state. If is, it may be determined that the power saving transition condition is not satisfied.

By doing so, it is possible to determine whether or not the power saving transition condition is satisfied according to the state of the electronic device, and to allow or reject the power saving transition request from the host device.

Further, in one aspect of the present invention, the first state may be a state in which the power consumption of the electronic device is lower than that of the second state.

In this way, when the electronic device is in the first state where the power consumption is smaller than the second state, the power saving transition request is permitted, and the second state where the power consumption is larger than the first state. In this state, the power saving transition request will be rejected.

Further, in one aspect of the present invention, the processing unit states that the power saving transition condition is satisfied when the power saving transition request is a request for shifting the communication bus to the first power saving state. If the power saving transition request is a request to shift the communication bus to the second power saving state, it may be determined that the power saving transition condition is not satisfied.

In this way, in the case of the power saving transition request to the first power saving state, the power saving transition request is permitted, and the transition to the first power saving state is started, and the second power saving is performed. In the case of a power saving transition request to the power state, the power saving transition request is rejected and the second power saving state is not shifted.

Further, in one aspect of the present invention, the second power saving state is a power saving state in which the power consumption is smaller and the return time to the normal state is longer than the first power saving state. You may.

For example, the second power saving state is a power saving state in which the power consumption is smaller and the recovery time is longer than the first power saving state. Alternatively, the second power saving state may be a power saving state in which the power consumption is smaller or the recovery time is longer than the first power saving state.

Further, in one aspect of the present invention, when the command issued via the communication bus is the first command, the processing unit determines that the power saving transition condition is satisfied, and the command is used. In the case of the second command, it may be determined that the power saving transition condition is not satisfied.

By doing so, it is determined whether or not the power saving transition condition is satisfied according to the type and content of the command issued via the communication bus, and the power saving transition request from the host device is permitted or rejected. It becomes possible to do.

Further, in one aspect of the present invention, the processing unit satisfies the power saving transition condition when the command issued via the communication bus is a command for which there is no information to be sent following the command. If the command has information to be sent following the command, it may be determined that the power saving transition condition is not satisfied.

In this way, in the case of a command that has information to be sent following the command, the speed can be increased by rejecting the power saving transition request from the host device. On the other hand, in the case of a command for which there is no information to be sent following the command, power saving can be achieved by permitting the power saving transition request.

Further, in one aspect of the present invention, when the communication unit receives a series of data from the host device, the processing unit does not satisfy the power saving transition condition during the transfer of the series of data. After the determination is completed and the transfer of the series of data is completed, it may be determined that the power saving transition condition is satisfied.

By doing so, since the power saving transition request is rejected during the transfer of a series of data, it is possible to prevent the situation of shifting to the power saving state. Then, after the transfer of a series of data is completed, the power saving transition request is permitted, so that the power saving state can be shifted to after the transfer of the series of data is completed, and the power saving can be achieved.

Further, in one aspect of the present invention, the series of data is print data, and the processing unit satisfies the power saving transition condition after receiving the print start command and before receiving the print end command. After receiving the print end command, it may be determined that the power saving transition condition is satisfied.

By doing so, during the reception of a series of print data, the power saving state is prevented from shifting, and the print data can be transferred at high speed. Then, after receiving the print end command, by permitting the power saving transition request, the power saving state can be shifted and the power saving can be achieved.

Further, in one aspect of the present invention, the USB communication bus may be a communication bus compliant with the USB3.0 or USB3.1 standard.

However, the communication bus of the present invention is not limited to this, and may be a communication bus compliant with a standard developed from USB3.0 or USB3.1.

Another aspect of the present invention is a communication processing method using a USB communication bus, in which a power saving transition condition is satisfied when a power saving transition request is received from a host device connected to the communication bus. If so, the power saving transition condition is satisfied when the power saving transition request is permitted, the communication bus is shifted to the power saving state, and the power saving transition request is received from the host device. If not, it relates to a communication processing method that rejects the power saving transition request and does not shift the communication bus to the power saving state.

In another aspect of the present invention, a computer functions as a communication unit that communicates via a USB communication bus and a processing unit that controls the communication unit, and the processing unit is connected to the communication bus. If the power saving transition condition is satisfied when the power saving transition request is received from the host device, the power saving transition request is permitted, the communication bus is shifted to the power saving state, and the power saving transition state is performed. If the transition condition is not satisfied, the present invention relates to a program that rejects the power saving transition request and does not shift the communication bus to the power saving state.

Configuration example of the electronic device of this embodiment. An explanatory diagram of a USB connection between a PC (host device) and a printer (electronic device). Explanatory drawing about USB communication processing. Explanatory drawing about the power saving state which can be migrated. A communication sequence diagram illustrating conventional problems. The communication sequence diagram explaining the method of this embodiment. The communication sequence diagram explaining the 1st application example of the method of this embodiment. The communication sequence diagram explaining the 2nd application example of the method of this embodiment. Explanatory drawing of power saving state U1 and U2. The communication sequence diagram explaining the 3rd application example of the method of this embodiment. The communication sequence diagram of the transition permission from the normal state U0 to the power saving state U1. The communication sequence diagram of the transition refusal from the normal state U0 to the power saving state U1. The communication sequence diagram of the return from the power saving state U1 to the normal state U0. The communication sequence diagram of the transition permission from the normal state U0 to the power saving state U2. The communication sequence diagram of the transition refusal from the normal state U0 to the power saving state U2. The communication sequence diagram of the return from the power saving state U2 to the normal state U0. The communication sequence diagram of the transition permission from the normal state L0 to the power saving state L1. The communication sequence diagram of the transition refusal from the normal state L0 to the power saving state L1. The communication sequence diagram of the return from the power saving state L1 to the normal state L0. State transition diagram of U0, U1, U2. The communication sequence diagram explaining the transition by the time-out from the power saving state U1 to U2. The communication sequence diagram of the method of forcibly returning to the normal state U0 before the time-out time elapses.

Hereinafter, preferred embodiments of the present invention will be described in detail. It should be noted that the present embodiment described below does not unreasonably limit the content of the present invention described in the claims, and all of the configurations described in the present embodiment are indispensable as the means for solving the present invention. Not necessarily.

1. 1. Electronic device FIG. 1 shows a configuration example of the electronic device 10 of the present embodiment. The electronic device 10 includes a processing unit 20 and a communication unit 30. Further, the electronic device 10 can further include a storage unit 50, an operation unit 60, a display unit 70, and a printing unit 80. The processing unit 20, the communication unit 30, the storage unit 50, the operation unit 60, the display unit 70, and the printing unit 80 are electrically connected via signal wiring such as an internal bus of the electronic device 10.

The electronic device 10 is not limited to the configuration shown in FIG. 1, and various modifications such as omitting some of these components (for example, an operation unit, a display unit, a printing unit, etc.) or adding other components are added. It is possible to carry out. Further, the electronic device 10 is, for example, a printer (printing device). Alternatively, the electronic device 10 may be a scanner, a facsimile machine or a copier. The electronic device 10 may be a multifunction device (MFP: Multifunction Peripheral) having a plurality of functions, and a multifunction device having a printing function is also an example of a printer. Alternatively, the electronic device 10 includes a projector, a head-mounted display device, a wearable device (wrist-type wearable device, etc.), a biometric information measuring device (pulse meter, pedometer, activity meter, etc.), a robot, a video device (camera, etc.). , A portable information terminal (smartphone, portable game machine, etc.), a physical quantity measuring device, or the like.

The processing unit 20 (processor, controller) controls each unit (communication unit, storage unit, printing unit, etc.) of the electronic device 10, and performs various processes of the present embodiment. For example, the processing unit 20 can include a plurality of CPUs (MPU, microcomputer) such as a main CPU 21 and a sub CPU 22. The main CPU 21 (main control board) controls each part of the electronic device 10 and controls the whole. For example, when the electronic device 10 is a printer, the sub CPU 22 performs various processes related to printing. Alternatively, a CPU for communication processing may be further provided.

Each process (each function) of the present embodiment performed by the processing unit 20 can be realized by a processor (a processor including hardware). For example, each process of the present embodiment can be realized by a processor that operates based on information such as a program and a memory (storage device) that stores information such as a program. In the processor here, for example, the functions of each part may be realized by individual hardware, or the functions of each part may be realized by integrated hardware. For example, the processor includes hardware, which hardware can include at least one of a circuit that processes a digital signal and a circuit that processes an analog signal. For example, a processor can be composed of one or more circuit devices (eg, ICs, etc.) mounted on a circuit board, or one or more circuit elements (eg, resistors, capacitors, etc.). The processor may be, for example, a CPU. However, the processor is not limited to the CPU, and various processors such as a GPU (Graphics Processing Unit) or a DSP (Digital Signal Processor) can be used. Further, the processor may be a hardware circuit by ASIC.

The communication unit 30 (communication interface) can be realized by at least one communication device (communication IC, interface IC). The communication unit 30 performs USB communication processing, for example. For example, the communication unit 30 performs interface processing for high-speed serial communication with a host device (external device) via the USB communication bus BS. In this case, the communication unit 30 is realized by an IC or the like of a USB device controller. Alternatively, the communication unit 30 may perform wireless communication processing conforming to the standards of Bluetooth (Bluetooth is a registered trademark) and Wi-Fi (registered trademark).

The storage unit 50 (storage device, memory) stores various information such as data and programs. The processing unit 20 and the communication unit 30 operate, for example, using the storage unit 50 as a work area. The storage unit 50 may be a semiconductor memory such as SRAM or DRAM, a register, a magnetic storage device such as a hard disk device (HDD), or an optical disk device or the like. It may be an expression storage device. For example, the storage unit 50 stores instructions that can be read by a computer, and when the instructions are executed by the processing unit 20 (processor), the functions of each unit (communication unit, processing unit) of the electronic device 10 are realized. Will be done. The instruction here may be an instruction of an instruction set constituting the program, or may be an instruction instructing the hardware circuit of the processing unit 20 (processor) to operate.

The operation unit 60 (operation panel) is for the user to perform an input operation, and can be realized by an operation button, a key, a touch sensor, or the like. The display unit 70 (display) displays various types of information, and can be realized by a display such as a liquid crystal display or an organic EL. The operation unit 60 and the display unit 70 may be integrally configured by, for example, a touch panel.

The printing unit 80 is realized by a printing engine. A print engine is a mechanical configuration that prints an image on a print medium. The printing engine includes, for example, a transport mechanism, an inkjet discharge head, a drive mechanism of a carriage including the discharge head, and the like. The printing engine prints an image on the printing medium by ejecting ink from the ejection head onto the printing medium (paper or cloth) conveyed by the conveying mechanism. The specific configuration of the printing engine is not limited to the one illustrated here, and may be one that prints with toner by a laser method. Further, the printing unit 80 may include a sensor that detects various physical quantities related to the operating state of the printing engine, a counter that counts the detection result, and the like. By using a sensor or a counter, it is possible to acquire information such as the driving amount of the transport mechanism (rotation amount of the motor), the number of reciprocations of the ejection head, and the consumption amount of ink.

For example, the processing unit 20 and the communication unit 30 in FIG. 1 can perform each processing of the present embodiment based on the program. This program can be stored in an information storage medium, which is a medium that can be read by a computer, for example. The information storage medium can be realized by, for example, an optical disk, a memory card, an HDD, a semiconductor memory (ROM), or the like. The processing unit 20 and the communication unit 30 perform various processes of the present embodiment based on the program (data) stored in the information storage medium. That is, the information storage medium has a program (a program for causing the computer to execute the processing of each part) for functioning a computer (a device including an input device, a processing unit, a storage unit, and an output unit) as each part of the present embodiment. It will be remembered.

In FIG. 2, a printer 210, which is an example of an electronic device 10, and a PC 220 (personal computer), which is an example of a host device 90, are connected by a USB cable 230 having a USB communication bus BS. Then, the printer 210 receives print data from the PC 220 via the USB cable 230 (communication bus BS). Further, various status information of the printer 210 is transmitted from the printer 210 to the PC 220 via the USB cable 230. When the printer 210 is, for example, a multifunction device having a scanner function, the data read by the scanner of the printer 210 is transmitted from the printer 210 to the PC 220 via the USB cable 230.

Next, the communication process of USB3.0 will be described with reference to FIG. In the following, the case where the communication bus BS is a bus compliant with the USB3.0 standard will be mainly described as an example, but the communication bus BS in the present embodiment is an extension of USB3.0 such as USB3.1. The bus may be compliant with the standard. USB3.1 has a higher data transfer speed than USB3.0, and in addition to USB3.0's 5 Gbps data transfer mode (Super Speed (Gen1)), it has a higher speed of 10 Gbps data transfer mode (Super Speed). Plus (Gen2)) has been added.

As shown in FIG. 3, the communication unit 30 of the electronic device 10 is realized by, for example, a USB device controller (IC), and has an SS processing unit 34 and a Non-SS processing unit 36. The SS processing unit 34 processes, for example, a physical layer, a link layer, and a protocol layer in SS (Super Speed) mode compliant with USB3.0 (or USB3.1; the same applies hereinafter). The Non-SS processing unit 36 processes, for example, the physical layer, the link layer, and the protocol layer of the HS (High Speed) mode, the FS (Full Speed) mode, and the LS (Low Speed) mode of USB 2.0.

The communication unit 92 of the host device 90 is realized by, for example, a USB host controller (IC), and has an SS processing unit 94 and a Non-SS processing unit 96. The SS processing unit 94 processes, for example, the physical layer, the link layer, and the protocol layer of the SS mode compliant with USB3.0. The Non-SS processing unit 96 processes, for example, the physical layer, link layer, and protocol layer of USB 2.0 in HS mode, LS mode, and FS mode.

The USB cable 230 having the USB communication bus BS is connected to the USB connector 232 (downstream port) of the electronic device 10 and the USB connector 234 (upstream port) of the host device 90.

In USB3.0, SS mode is introduced in addition to HS mode of USB2.0. In the HS mode, half-duplex communication is performed in which the same communication line is switched between transmission and reception, and in SS mode, full-duplex communication in which a communication line dedicated to each of transmission and reception is performed is performed. Therefore, as shown in FIG. 3, the communication bus BS of the USB cable 230 has a communication line for SS (communication line for transmission and communication line for reception) and a communication line for Non-SS such as HS (for both transmission and reception). It has a communication line). As described above, in the SS mode, high-speed transfer of 5 Gbps, which is about 10 times that of the HS mode, is realized by performing full-duplex communication. In USB3.0, the link layer has various roles in order to absorb the greatly changed difference in the physical layer while maintaining backward compatibility with USB2.0. Specifically, the link layer manages link training, power management, framing, flow control and buffers.

In USB3.0, as a means for knowing the connection state on the opposite side, a process called receiver detection is performed as in the case of PCI Express. The receiver detection electrically and periodically determines whether or not the opposite side is in the connected state. Then, when the presence of the opposite side can be grasped by the receiver detection, a link training sequence is performed to physically and logically confirm the connection state. That is, synchronization is achieved with the linked device, and the link is established.

Specifically, in USB3.0, the link state of the serial communication bus is managed by the LTSSM (Link Training Status State Machine). Link power management is performed by this LTSSM. For example, in USB3.0 full-duplex communication, when a link becomes active, communication is continued using an idle signal even in an idle state. For this reason, power consumption increases, and power management by LTSSM enables unnecessary devices to stop communication and shift to a power saving state.

Specifically, the states of U0, U1, U2, and U3 are defined as the states of power management by LTSSM. U0 is a normal state, and is a state in which packet transfer with the link destination is performed. U1 is in a power saving state, packet transfer with the link destination is not performed, and for example, the transmission / reception circuit is stopped. That is, in U1, the packet transfer is stopped, and both sides of the link shift to the power saving state. However, it is required to maintain the operating state of the system to the extent that LFPS (Low Frequency Periodic Signaling), which is a low frequency burst signal, can be transmitted. U2 is in a power saving state with lower power than U1, but is in a state in which a recovery time (latency) is longer than that in U1. For example, the clock generation circuit is stopped. The transition from U1 to U2 is triggered by, for example, a timeout by a timer. This timer is LFPS. It is reset / restarted every time a ping is received. That is, both sides of the link migrate to U1 and periodically LFPS. As long as you keep sending Ping, the state of U1 is maintained. U3 is a state that shifts to the suspend state, and is the state with the lowest power consumption.

In the link layer, LGO_UX (transition request to U1, U2, U3), LAU (permission of migration request), LXU (rejection of migration request), LPMA (reception notification of LAU) are used as link commands for power management. It is prepared. By using these link commands, power management can be performed by the link layer, so that the processing load of the protocol layer and the application layer can be reduced.

2. 2. Method of the present embodiment As shown in FIG. 4, when the host device 90 does not support USB3.0, the communication speed of USB becomes HS, and it becomes possible to shift to the power saving state L1. For example, even in USB 2.0, states such as L1 (sleep) and L2 (suspend) are additionally defined as LPM (Link Power Management) states. On the other hand, when the host device 90 is compatible with USB3.0, the communication speed of USB becomes SS, and for example, it is possible to shift to the power saving states U1 and U2. These L1, U1 and U2 are in a power saving state in which the device side can reject the migration request from the host side. For example, L2, U3, etc. are states that cannot be rejected from the host side in response to the migration request.

Then, when the USB communication bus BS is in the power saving state, it is necessary to first recover from the power saving state at the time of USB communication. Therefore, there arises a problem that the recovery time becomes a time loss and the start of USB communication is delayed.

For example, as shown in FIG. 5, the host device 90 (USB host) makes a power saving transition request (transition request to the power saving state) to the electronic device 10 (USB device), and the electronic device 10 permits the migration request. Then, the USB communication bus BS is in a power saving state. If the host device 90 wants to send a command when the power saving state is reached in this way, a power saving return request (return request to the power saving state) is made, and the electronic device 10 permits this return request. There is a need to. Then, with the permission of the return request, the communication bus BS needs to return to the normal state, and then the host device 90 needs to send a command. Therefore, the host device 90 cannot immediately transmit the command, and the transmission of the command is delayed by the time lag of the return time. For example, when the electronic device 10 is a printer and the command is a print command, there arises a problem that the start of printing is delayed and the user is kept waiting.

Therefore, in the present embodiment, a method for speeding up USB communication is adopted by forcibly rejecting the power saving transition request. That is, as shown in FIG. 6, the electronic device 10 can reject the power saving transition request from the host device 90. For example, if the power saving transition condition is satisfied, the power saving transition request is permitted, and if the power saving transition condition is not satisfied, the power saving transition request can be rejected. As a result, it is prevented that the communication bus BS shifts to the power saving state as shown in FIG. 5, and the communication bus BS (link layer state) is maintained in the normal state as shown in FIG. Therefore, the host device 90 can immediately send a command, and can realize high-speed USB communication. Taking a printer as an example, print commands can be sent immediately, reducing the user's waiting time for printing.

Specifically, as shown in FIG. 1, the electronic device 10 of the present embodiment includes a communication unit 30 that communicates via a USB communication bus BS and a processing unit 20 that controls the communication unit 30. For example, the program of this embodiment causes a computer (electronic device) to function as a communication unit 30 that communicates via a USB communication bus BS and a processing unit 20 that controls the communication unit 30. Then, when the processing unit 20 receives the power saving transition request from the host device 90 connected to the communication bus BS, if the power saving transition condition is satisfied, the processing unit 20 permits the power saving transition request and the communication bus. The BS (link state) is shifted to a power saving state (for example, U1, U2). On the other hand, if the power saving transition condition is not satisfied, the processing unit 20 rejects the power saving transition request and prevents the communication bus BS (link state) from shifting to the power saving state. That is, as shown in FIG. 6, the power saving transition request from the host device 90 is rejected, and the communication bus BS is maintained in the normal state (for example, U0). As described above, in the communication processing method of the present embodiment using the USB communication bus BS, when the power saving transition request is received from the host device 90, if the power saving transition condition is satisfied, the power saving transition request is made. Allows the communication bus BS to shift to the power saving state, and if the power saving transition condition is not satisfied, rejects the power saving transition request and prevents the communication bus BS from shifting to the power saving state. ..

By doing so, when the power saving transition condition is satisfied, the power saving transition request from the host device 90 is permitted, and the power saving state is entered, so that the power saving can be realized. On the other hand, if the power saving transition condition is not satisfied, the power saving transition request from the host device 90 is rejected, so that it is possible to prevent the recovery time from being lost and the command execution from being delayed, and the USB. Communication and job execution can be speeded up. When the electronic device 10 is a printer, for example, the waiting time for printing can be shortened. Therefore, it is possible to realize both high-speed USB communication and job execution and power saving.

For example, depending on the host device 90, a power saving transition request may be made every time a command is issued. If the electronic device 10 connected to the host device 90 via the communication bus BS cannot reject the power saving transition request, the electronic device 10 shifts to the power saving state every time a command is issued. There is a problem that the speed of USB communication and job execution is hindered, and the processing load of the electronic device 10 for responding to the power saving transition request becomes excessive. In this respect, in the present embodiment, if the power saving transition condition is not satisfied, the power saving transition request from the host device 90 is rejected, so that the occurrence of such a problem can be prevented.

The power saving transition condition is, for example, a condition that serves as a standard for determining whether to permit or reject the transition to the power saving state. The power saving transition conditions are based on, for example, the state of the electronic device 10 (normal state, power saving state, etc.), the content and type of the power saving state subject to the power saving transition request, the content and type of the issued command, and the like. Is set. Further, as will be described later, the power saving transition request is, for example, LGO_U1, LGO_U2, LPM, or the like. The permission of the power saving transition request is, for example, LAU, ACK, or the like. The refusal of the power saving transition request is, for example, LXU, NAK, or the like.

FIG. 7 is a diagram illustrating a first application example of the method of the present embodiment. In FIG. 7, when the electronic device 10 as a USB device has a plurality of states, the response to the power saving transition request is switched according to the states to achieve both high speed and low power consumption of USB communication and the like. To be realized.

For example, as shown in FIG. 7, when the electronic device 10 is in the normal state (broadly defined as the second state), the power saving transition request from the host device 90 is rejected. That is, when the electronic device 10 is in a normal state (idle state) instead of a power saving state such as a sleep state, it is determined that the power saving transition condition is not satisfied, and the power saving transition request is rejected. .. On the other hand, when the electronic device 10 is in the power saving state (in a broad sense, the first state), the power saving transition request from the host device 90 is permitted. That is, when the electronic device 10 is in a power saving state such as a sleep state, a clock down state, or a deep sleep state, it is determined that the power saving transition condition is satisfied, and the power saving transition request is permitted.

As described above, in the present embodiment, when the state of the electronic device 10 is the first state, the processing unit 20 determines that the power saving transition condition is satisfied, and the state of the electronic device 10 is the second state. If it is in the state, it is determined that the power saving transition condition is not satisfied. That is, when the electronic device 10 is in the first state such as the power saving state, it is determined that the power saving transition condition is satisfied, the power saving transition request from the host device 90 is permitted, and the USB communication is performed. Move the bus BS to a power saving state. On the other hand, when the electronic device 10 is in the second state such as the normal state, it is determined that the power saving transition condition is not satisfied, the power saving transition request from the host device 90 is rejected, and the USB communication bus is used. Prevent the BS from shifting to a power saving state. Here, for example, the first state is a state in which the power consumption of the electronic device 10 is lower than that in the second state. That is, the power consumption of the electronic device 10 in the first state (for example, the sleep state) is smaller than the power consumption of the electronic device 10 in the second state (for example, the normal state).

By doing so, it is possible to determine whether or not the power saving transition condition is satisfied according to the state of the electronic device 10, and to allow or reject the power saving transition request from the host device 90. Therefore, it is possible to determine whether or not the power saving transition condition that reflects the state of the electronic device 10 is satisfied, and it is possible to realize appropriate power saving transition control. For example, when the electronic device 10 is in the normal state, the communication bus BS can be maintained in the normal state by rejecting the power saving transition request sent by the host device 90 after issuing the command. Therefore, as shown in FIG. 6, the next time the host device 90 issues a command, the command can be executed immediately. Taking the case where the electronic device 10 is a printer as an example, it is possible to avoid the situation where the communication bus BS shifts to the power saving state every time the host device 90 sends a print command, and the print command sent by the host device 90 can be avoided. Can be processed one after another. On the other hand, when the electronic device 10 is in the power saving state, the power saving transition request from the host device 90 is permitted so that not only the electronic device 10 but also the USB communication bus BS shifts to the power saving state. become. Therefore, it becomes possible to further reduce the power consumption of the system including the electronic device 10, the electronic device 10, and the host device 90.

For example, when the electronic device 10 is a printer, the normal state of the electronic device 10 is an idle state. This idle state is a standby state in which the print process can be immediately executed in response to a print instruction (print command) from the printer. The power saving state of the electronic device 10 is a sleep state, a clock down state, a deep sleep state, or the like. The sleep state is, for example, a state in which some units of the printer are set to the power saving state. For example, the print engine which is the printing unit 80 of FIG. 1 and the operation panel which is the operation unit 60 and the display unit 70 are set to the power saving state. Specifically, some functions of the printing engine are stopped, or the backlight of the display on the operation panel is turned off. In the clock down state, in addition to the sleep state, the frequency of the operating clock of, for example, the main CPU 21 in FIG. 1 is lowered. In the deep sleep state, some units of the printer are set to the power off state, and the main CPU 21 is also set to the power off state. For example, the storage unit 50 is also set to the power off state. The communication unit 30 is set to, for example, a power saving state.

The first state of the electronic device 10 determined to satisfy the power saving transition condition and the second state of the electronic device 10 determined not to satisfy the power saving transition condition are various. Can be assumed. For example, the first state may be the power saving state of the electronic device 10, and the second state may be the normal state (idle state) of the electronic device 10. Alternatively, the first state is the clock down state of the electronic device 10, the second state is the sleep state, or the first state is the deep sleep state and the second state is the clock down state. May be good. In this way, by determining that the power saving transition condition is satisfied in the first state where the power consumption is smaller than that in the second state, the system including the electronic device 10, the electronic device 10, and the host device 90 can be upgraded. It is possible to save power. Further, in the second state where the power consumption is larger than that in the first state, it is possible to speed up the USB communication and job execution by determining that the power saving transition condition is not satisfied.

FIG. 8 is a diagram illustrating a second application example of the method of the present embodiment. In FIG. 8, the response to the power saving transition request is switched according to the power saving state that is the target of the power saving transition request, and both high speed and low power consumption of USB communication and the like are realized.

For example, as shown in FIG. 8, when the power saving transition request from the host device 90 is a transition request to the power saving state U2 (broadly speaking, the second power saving state), this power saving transition request is made. Try to refuse. That is, it is determined that the power saving transition condition is not satisfied, and the power saving transition request can be rejected. On the other hand, when the transition request coming from the host device 90 is a transition request to the power saving state U1 (broadly speaking, the first power saving state), the power saving transition request from the host device 90 is permitted. That is, it is determined that the power saving transition condition is satisfied, and the power saving transition request is permitted.

As described above, in the present embodiment, the processing unit 20 determines that the power saving transition condition is satisfied when the power saving transition request is a request for shifting the communication bus BS to the first power saving state. If the power saving transition request is a request to shift the communication bus BS to the second power saving state, it is determined that the power saving transition condition is not satisfied. That is, in the case of the first power saving transition request, it is determined that the power saving transition condition is satisfied, the power saving transition request from the host device 90 is permitted, and the USB communication bus BS is used. Move to a power saving state. On the other hand, in the case of the second power saving transition request, it is determined that the power saving transition condition is not satisfied, the power saving transition request from the host device 90 is rejected, and the communication bus BS is saved. Do not shift to the power state.

Here, for example, the second power saving state is a power saving state in which the power consumption is smaller and the return time to the normal state is longer than that of the first power saving state. For example, the second power saving state is a power saving state in which the power consumption is smaller and the recovery time is longer than the first power saving state. Alternatively, the second power saving state may be a power saving state in which the power consumption is smaller or the recovery time is longer than the first power saving state. Specifically, as shown in FIG. 9, the power saving state U1, which is an example of the first power saving state, consumes a large amount of power but has a short recovery time from the power saving state. On the other hand, in the power saving state U2, which is an example of the second power saving state, the power consumption is small, but the recovery time from the power saving state is long.

As described above, in the power saving state U2, the recovery time from the power saving state is long, so that the recovery time becomes a time loss and the start of USB communication is delayed. For example, as shown in FIG. 5, during the long recovery time of the power saving state U2, the next command cannot be transmitted, which hinders the speeding up of USB communication and job execution. Since the latency of the power saving state U2 is, for example, on the order of ms (low ms range), waiting for such a long recovery time is a major obstacle to speeding up.

In this regard, in the present embodiment, as shown in FIG. 8, the electronic device 10 rejects the request for transition from the host device 90 to the power saving state U2. That is, in the case of a request for transition to the power saving state U2, the processing unit 20 determines that the power saving transition condition is not satisfied, and rejects the transition request. Therefore, it is not necessary to wait for the return time, which is on the order of ms, and the speed of USB communication and job execution can be increased.

On the other hand, the power saving state U1 consumes more power than U2, but the recovery time from the power saving state is short, for example, the recovery time on the order of μs. Therefore, even if the request for transition to the power saving state U1 is permitted as shown in FIG. 8, it does not hinder the speeding up so much as compared with the case where the power saving state U2 is permitted. Then, by permitting the request for transition to the power saving state U1, the power saving can be achieved. That is, by permitting the request for transition to the power saving state U1 and rejecting the request for transitioning to the power saving state U2, both speeding up of USB communication and job execution and power saving are realized at the same time. Will be possible.

For example, depending on the host device 90, a power saving transition request may be made every time a command is issued. When the power saving transition request made every time a command is issued is U1, even if the transition request is permitted, the recovery time is short, so that the speedup is not so hindered. Then, by permitting the transition request to U1, power saving can be realized. That is, power saving is prioritized at the expense of speeding up to some extent. On the other hand, in the case of a U2 migration request, if this is permitted, it will not be possible to wait for the return time of the ms order. Therefore, the U2 migration request is rejected and communication and job execution are performed at high speed. Aim for conversion. That is, at the expense of power saving to some extent, priority is given to speeding up. In the above, the case where the first power saving state is U1 and the second power saving state is U2 has been mainly described as an example, but the present embodiment is not limited to this, and the first and second power saving states are not limited to this. The power saving state of may be a power saving state other than U1 and U2.

FIG. 10 is a diagram illustrating a third application example of the method of the present embodiment. In FIG. 10, the response to the power saving transition request is switched according to the command received from the host device 90 by the electronic device 10, to realize both high speed and low power consumption of USB communication and the like.

For example, FIG. 10 shows an example of a communication sequence when the electronic device 10 is a printer, and the host device 90 sends a print start command to the electronic device 10. When the command received from the host device 90 is the print start command in this way, the power saving transition request from the host device 90 is rejected as shown in FIG. Specifically, the power saving transition request from the host device 90 is rejected until the print end command is received. When the print end command is received from the host device 90, the power saving transition request from the host device 90 is permitted. As described above, in the third application example, the response (rejection, permission) to the power saving transition request is switched according to the command (print start command, print end command) received from the host device 90.

As described above, in the present embodiment, when the command issued via the communication bus BS is the first command, the processing unit 20 determines that the power saving transition condition is satisfied, and the command is the second command. If it is a command, it is determined that the power saving transition condition is not satisfied. That is, when the command received from the host device 90 is the first command (for example, the print end command), it is determined that the power saving transition condition is satisfied, and the power saving transition request from the host device 90 is permitted. Then, the USB communication bus BS is shifted to the power saving state. On the other hand, when the command received from the host device 90 is the second command (for example, the print start command), the processing unit 20 determines that the power saving transition condition is not satisfied, and saves the power from the host device 90. Reject the power transfer request to prevent the communication bus BS from shifting to the power saving state.

In this way, depending on the type and content of the command issued via the communication bus BS, it is determined whether or not the power saving transition condition is satisfied, and the power saving transition request from the host device 90 is permitted. , It will be possible to refuse. Therefore, it is possible to determine whether or not the power saving transition condition is satisfied that reflects the type and content of the command, and it is possible to realize appropriate power saving transition control.

For example, as shown in FIG. 10, when the command received from the host device 90 is the print start command, the print data is received via the communication bus BS after the print start command is received. If the power saving transition request from the host device 90 is permitted during such a print data reception period, the transfer of a series of print data is stopped, and during the recovery time from the power saving state, the transfer is stopped. There will be a situation that makes the user wait.

In this respect, in the present embodiment, when the command received from the host device 90 is the print start command, the subsequent power saving transition request from the host device 90 is rejected, and the transfer of a series of print data is not stopped. To do so. As a result, it is possible to prevent the occurrence of a situation in which the user is kept waiting during the recovery time from the power saving state. Then, when the print end command is received from the host device 90, the subsequent power saving transition request from the host device 90 is permitted to realize the power saving. By doing so, it becomes possible to realize both high-speed USB communication and job execution and low power consumption.

For example, in the present embodiment, the processing unit 20 determines that the power saving transition condition is satisfied when the command issued via the communication bus BS is a command for which there is no information to be sent following the command. .. On the other hand, if the command has information to be sent following the command, the processing unit 20 determines that the power saving transition condition is not satisfied. That is, when a command (for example, a print end command) for which there is no information to be sent is received following the command, it is determined that the power saving transition condition is satisfied, and the subsequent power saving transition request from the host device 90 is performed. To realize power saving. On the other hand, when a command (for example, a print start command) having information to be sent is received following the command, it is determined that the power saving transition condition is not satisfied, and the subsequent power saving transition request from the host device 90 is performed. Is rejected to achieve higher speed.

For example, in the case of a command that has information (print data) to be sent following the command, such as the print start command, if the power saving transition request from the host device 90 is permitted, the transfer of the information will stop. This causes a problem that keeps the user waiting.

In this respect, in the present embodiment, when such a command is received, the power saving transition request from the host device 90 is rejected, so that it is possible to prevent the occurrence of problems such as making the user wait. On the other hand, in the case of a command such as a print end command in which there is no information to be sent following the command, the above problem does not occur even if the power saving transition request from the host device 90 is permitted. Then, by permitting the power saving transition request, the power saving can be achieved.

The commands that have information to be sent following the command include, for example, a job execution start instruction command such as a print start command, and status information of the electronic device 10 (for example, ink remaining amount, print count information, error information). Various commands such as acquisition commands can be assumed. For example, when the electronic device 10 is a scanner or a multifunction device having a scanner function, the command requested by the host device 90 to transfer the read data of the scanner is also a command having information to be sent following the command. .. Further, as a command for which there is no information to be sent following the command, various commands such as a job end instruction command such as a print end command and a command for setting an operation for the electronic device 10 can be assumed. For example, when a job end instruction command is received from the host device 90, it is considered that the electronic device 10 does not have to execute the job for a while after that. Therefore, in this case, the power saving transition request from the host device 90 is permitted, and the power saving is realized. When a command for setting the operation mode of the electronic device 10 is received from the host device 90, power saving from the host device 90 is performed until a job execution start command is subsequently received from the host device 90. By allowing the migration request, it will be possible to save power.

Further, in the present embodiment, when the communication unit 30 receives a series of data from the host device 90, the processing unit 20 determines that the power saving transition condition is not satisfied during the transfer of the series of data, and determines that the power saving transition condition is not satisfied, and the series of data. After the transfer is completed, it is determined that the power saving transition condition is satisfied. For example, it is determined that the power saving transition condition is not satisfied during the transfer of a series of data, and the power saving transition request from the host device 90 is rejected. After the transfer of a series of data is completed, it is determined that the power saving transition condition is satisfied, and the power saving transition request from the host device 90 is permitted.

By doing so, since the power saving transition request is rejected during the transfer of a series of data, the transition to the power saving state is prevented and the series of data can be transferred at high speed. On the other hand, after the transfer of a series of data is completed, the power saving transition request is permitted, so that the power saving state can be shifted to after the transfer is completed, and the power saving can be achieved.

Specifically, as shown in FIG. 10, the series of data is print data. Then, the processing unit 20 determines that the power saving transition condition is not satisfied after receiving the print start command and before receiving the print end command, and after receiving the print end command, the power saving transition condition. Is determined to hold. That is, after receiving the print start command and before receiving the print end command, the power saving transition request from the host device 90 is rejected, and after receiving the print end command, the power saving transition request from the host device 90 is made. to approve.

By doing so, during the reception of a series of print data, the power saving state is prevented from shifting, and the print data can be transferred at high speed. Then, after receiving the print end command, by permitting the power saving transition request, the power saving state can be shifted and the power saving can be achieved.

For example, when the application program of the host device 90 instructs to print the print data of the predetermined data amount, the communication unit 92 (FIG. 3) of the host device 90 divides the print data of the predetermined data amount into a plurality of data blocks. May be sent. At this time, depending on the host device 90, a power saving transition request may be made every time one data block is transmitted. For example, the communication unit 92, which is a hardware circuit, automatically divides the print data of a predetermined amount of data instructed by the application program into a plurality of data blocks. Then, in order to save power, a power saving transition request is made for each transmission of each data block. If such a power saving transition request for each data block is permitted, there arises a problem that it takes a long time to complete the transfer of print data (a series of print data) of a predetermined data amount.

In this regard, according to the present embodiment, even if the host device 90 makes a power saving transition request after transmitting one data block, the power saving transition request is rejected. For example, after receiving a print start command for a predetermined amount of print data (a series of print data), a power saving transition request from the host device 90 until the print end command for the print data of the predetermined data amount is received. Is rejected. Then, after receiving the print end command, the power saving transition request from the host device 90 is permitted. By doing so, the print data of the predetermined data amount will not be transferred to the power saving state until the transfer of the print data of the predetermined data amount instructed by the application program is completed. Therefore, the print data of the predetermined data amount is transferred to the USB communication bus. It will be possible to transfer at high speed via BS. Then, by permitting the power saving transition request after the transfer of the print data of the predetermined data amount, the power saving can be achieved.

3. 3. Details of power saving transition and power saving recovery Next, a detailed example of the communication sequence of power saving transition and power saving recovery will be described. 11, 12, and 13 are communication sequence diagrams for transition permission, transition refusal, and return from the normal state U0 to the power saving state U1. In the following, the host device 90 will be described as a USB host, and the electronic device 10 will be described as a USB device.

LGO_U1 is used to shift from the normal state U0 to the power saving state U1. This LGO_U1 can be transmitted by both a USB host and a USB device. When the receiving side receives LGO_U1, it needs to respond with LAU (permission) or LXU (rejection) and notify whether or not the transition to U1 is possible. Then, in FIG. 11, LAU (permission) is returned to LGO_U1, and the request for transition to the power saving state U1 is permitted. In this case, the USB host transmits LPMA and shifts to the power saving state U1. This LPMA is a command for a handshake indicating that the power saving state is about to be reached. On the other hand, in FIG. 12, LXU (rejection) is returned to LGO_U1, the request for transition to the power saving state U1 is rejected, and the normal state U0 is maintained.

As shown in FIG. 13, when returning from the power saving state U1 to the normal state, the USB host or the USB device transmits the LFPS Handshake (U1exit). When the receiving side receives this, it responds with the LFPS Handshake (U1exit), and the USB host and the USB device are in the Recovery state in which U0 is being restored. In the Recovery state, synchronous communication called Link Training is performed, and when the synchronization is completed, the USB host and the USB device return to the normal state U0.

14, 15, and 16 are communication sequence diagrams for transition permission, transition refusal, and return from the normal state U0 to the power saving state U2. The transition sequence to U2 is very similar to the transition sequence to U1, and instead of LGO_U1 used in the transition to U1, LGO_U2 is used as shown in FIG. Like LGO_U1, this LGO_U2 can be transmitted by both the USB host and the USB device. When the receiving side receives LGO_U2, it needs to respond with LAU (permission) or LXU (rejection) and notify whether or not the transition to U2 is possible. Then, as shown in FIG. 14, when LAU (permission) is returned to LGO_U2, the transmitting side transmits LPMA and shifts to the power saving state U2. On the other hand, as shown in FIG. 15, when LXU (rejection) is returned to LGO_U2, the normal state U0 is maintained.

As shown in FIG. 15, the return sequence to the power saving state U2 is very similar to the return sequence to the power saving state U1, but as described in FIG. 9 above, U2 takes longer to return than U1. long. Then, when returning from U2 to U0, the USB host or USB device transmits an LFPS Handshake (U2exit). When the receiving side receives this, it responds with the LFPS Handshake (U2exit), and the USB host and the USB device are in the Recovery state in which the USB host and the USB device are returning to U0. In the Recovery state, synchronous communication called Link Training is performed, and when the synchronization is completed, the USB host and the USB device return to the normal state U0.

17, FIG. 18 and FIG. 19 are communication sequence diagrams for transition permission, transition refusal, and return from the normal state L0 to the power saving state L1. As shown in FIG. 17, LPM is used to shift from the normal state L0 to the power saving state L1. This is different from LGO_U1 and LGO_U2, and only the USB host can transmit. The USB device responds to the LPM with ACK (permit) or NAK (deny), and notifies whether or not the transition to the power saving state L1 is possible. As shown in FIG. 17, when the USB device responds to LPM by ACK, the request for transition to the power saving state L1 is permitted, and the USB device shifts to the power saving state L1. On the other hand, as shown in FIG. 18, when the USB device responds to LPM by NAK, the request for transition to the power saving state L1 is rejected, and the normal state L0 is maintained. Further, as shown in FIG. 19, when returning from the power saving state L1 to the normal state L0, the process returns from L1 to L0.

FIG. 20 is a state transition diagram of the normal state U0 and the power saving states U1 and U2. As described above, the transition from the normal state U0 to the power saving states U1 and U2 is performed by LGO_U1 and LGO_U2, respectively. These LGO_U1 and LGO_U2 can be rejected. On the other hand, the transition from the power saving state U1 to U2 is caused by a timeout by the timer. The timer is set by the USB host when the communication is connected. The timer can be set, for example, in the range of 256 μs to 65.024 ms. Then, as shown in FIG. 21, the power saving state U1 to U2 automatically transitions to U2 due to a timeout. Therefore, it seems that there is no point in rejecting the request for transition to the power saving state U2, but at least the immediate transition to U2 can be prevented, so it is meaningful to reject the request for transition to U2.

There is also a method for preventing the transition from the power saving state U1 to U2. As shown in FIG. 22, it is a method of forcibly returning to the normal state U0 after shifting to the power saving state U1 and before the timeout time by the timer elapses. The USB device can take the initiative in issuing a request to return to the normal state U0. As another method, for example, it is possible to set to disable the timeout. In that case, the transition from the power saving state U1 to the U2 cannot be performed, and the normal state U0 must be passed.

Although the present embodiment has been described in detail as described above, those skilled in the art will easily understand that many modifications that do not substantially deviate from the novel matters and effects of the present invention are possible. Therefore, all such modifications are included in the scope of the present invention. For example, terms described at least once in the specification or drawings with different terms (first state, second state, first power saving state, second power saving state, etc.). Power saving state, normal state, power saving state U1, power saving state U2, etc.) can be replaced with different terms anywhere in the specification or drawings. Further, the configuration of the electronic device, communication processing, and the like are not limited to those described in the present embodiment, and various modifications can be made.

BS ... communication bus, L0 ... normal state, L1 ... power saving state,
U0 ... normal state, U1, U2 ... power saving state,
10 ... Electronic device, 20 ... Processing unit, 21 ... Main CPU, 22 ... Sub CPU,
30 ... Communication unit, 34 ... SS processing unit, 36 ... Non-SS processing unit, 50 ... Storage unit,
60 ... operation unit, 70 ... display unit, 80 ... printing unit, 90 ... host device, 92 ... communication unit,
94 ... SS processing unit, 96 ... Non-SS processing unit,
210 ... printer, 220 ... PC, 230 ... USB cable,
232, 234 ... USB connector

Claims (15)

With the communication unit that communicates via the USB communication bus,
A processing unit that controls the communication unit and
Including
The processing unit
If the power saving transition condition is satisfied when the power saving transition request is received from the host device connected to the communication bus, the power saving transition request is permitted and the communication bus is put into the power saving state. If the transition is performed and the power saving transition condition is not satisfied, the power saving transition request is rejected and the communication bus is not shifted to the power saving state.
The processing unit
When the power saving transition request is a request for shifting the communication bus to the first power saving state, it is determined that the power saving transition condition is satisfied, and the power saving transition request is the communication bus. When it is a request to shift to the second power saving state, the electronic device is characterized in that it is determined that the power saving transition condition is not satisfied. In claim 1,
The second power saving state is an electronic device characterized in that it is a power saving state in which the power consumption is smaller and the return time to the normal state is longer than that of the first power saving state. With the communication unit that communicates via the USB communication bus,
A processing unit that controls the communication unit and
Including
The processing unit
If the power saving transition condition is satisfied when the power saving transition request is received from the host device connected to the communication bus, the power saving transition request is permitted and the communication bus is put into the power saving state. If the transition is performed and the power saving transition condition is not satisfied, the power saving transition request is rejected and the communication bus is not shifted to the power saving state.
The processing unit
If the command issued via the communication bus is a command for which there is no information to be sent following the command, it is determined that the power saving transition condition is satisfied, and there is information to be sent following the command. When it is a command, it is an electronic device characterized in that it is determined that the power saving transition condition is not satisfied. With the communication unit that communicates via the USB communication bus,
A processing unit that controls the communication unit and
Including
The processing unit
If the power saving transition condition is satisfied when the power saving transition request is received from the host device connected to the communication bus, the power saving transition request is permitted and the communication bus is put into the power saving state. If the transition is performed and the power saving transition condition is not satisfied, the power saving transition request is rejected and the communication bus is not shifted to the power saving state.
The processing unit
When the power saving transition request is a transition request to the power saving state U1, it is determined that the power saving transition condition is satisfied, and when the power saving transition request is a transition request to the power saving state U2. Is an electronic device characterized in that it is determined that the power saving transition condition is not satisfied. In any of claims 1 to 4,
The processing unit
When the state of the electronic device is the first state, it is determined that the power saving transition condition is satisfied, and when the state of the electronic device is the second state, the power saving transition condition is satisfied. An electronic device characterized in that it is determined not to be present. In claim 5,
The first state is an electronic device characterized in that the power consumption of the electronic device is lower than that of the second state. In any of claims 1 to 6,
The processing unit
When the communication unit receives a series of data from the host device, it is determined that the power saving transition condition is not satisfied during the transfer of the series of data, and after the transfer of the series of data is completed, the communication unit determines that the power saving transition condition is not satisfied. An electronic device characterized in that it is determined that the power saving transition condition is satisfied. In claim 7,
The series of data is print data and is
The processing unit
After receiving the print start command and before receiving the print end command, it is determined that the power saving transition condition is not satisfied, and after receiving the print end command, the power saving transition condition is satisfied. An electronic device characterized in that it is determined to be. In any one of claims 1 to 8,
The USB communication bus is an electronic device characterized by being a communication bus compliant with the USB3.0 or USB3.1 standard. It is a communication processing method using a USB communication bus.
If the power saving transition condition is satisfied when the power saving transition request is received from the host device connected to the communication bus, the power saving transition request is permitted and the communication bus is put into the power saving state. Migrate,
If the power saving transition condition is not satisfied when the power saving transition request is received from the host device, the power saving transition request is rejected and the communication bus is not shifted to the power saving state.
When the power saving transition request is a request for shifting the communication bus to the first power saving state, it is determined that the power saving transition condition is satisfied, and the power saving transition request is the communication bus. When it is a request to shift to the second power saving state, the communication processing method is characterized in that it is determined that the power saving transition condition is not satisfied. It is a communication processing method using a USB communication bus.
If the power saving transition condition is satisfied when the power saving transition request is received from the host device connected to the communication bus, the power saving transition request is permitted and the communication bus is put into the power saving state. Migrate,
If the power saving transition condition is not satisfied when the power saving transition request is received from the host device, the power saving transition request is rejected and the communication bus is not shifted to the power saving state.
If the command issued via the communication bus is a command for which there is no information to be sent following the command, it is determined that the power saving transition condition is satisfied, and there is information to be sent following the command. When it is a command, it is a communication processing method characterized in that it is determined that the power saving transition condition is not satisfied. It is a communication processing method using a USB communication bus.
If the power saving transition condition is satisfied when the power saving transition request is received from the host device connected to the communication bus, the power saving transition request is permitted and the communication bus is put into the power saving state. Migrate,
If the power saving transition condition is not satisfied when the power saving transition request is received from the host device, the power saving transition request is rejected and the communication bus is not shifted to the power saving state.
When the power saving transition request is a transition request to the power saving state U1, it is determined that the power saving transition condition is satisfied, and when the power saving transition request is a transition request to the power saving state U2. Is a communication processing method characterized in that it is determined that the power saving transition condition is not satisfied. With the communication unit that communicates via the USB communication bus,
As a processing unit that controls the communication unit,
Make your computer work
The processing unit
If the power saving transition condition is satisfied when the power saving transition request is received from the host device connected to the communication bus, the power saving transition request is permitted and the communication bus is put into the power saving state. If the transition is performed and the power saving transition condition is not satisfied, the power saving transition request is rejected and the communication bus is not shifted to the power saving state.
The processing unit
When the power saving transition request is a request for shifting the communication bus to the first power saving state, it is determined that the power saving transition condition is satisfied, and the power saving transition request is the communication bus. Is a request to shift to the second power saving state, the program is characterized in that it is determined that the power saving transition condition is not satisfied. With the communication unit that communicates via the USB communication bus,
As a processing unit that controls the communication unit,
Make your computer work
The processing unit
If the power saving transition condition is satisfied when the power saving transition request is received from the host device connected to the communication bus, the power saving transition request is permitted and the communication bus is put into the power saving state. If the transition is performed and the power saving transition condition is not satisfied, the power saving transition request is rejected and the communication bus is not shifted to the power saving state.
The processing unit
If the command issued via the communication bus is a command for which there is no information to be sent following the command, it is determined that the power saving transition condition is satisfied, and there is information to be sent following the command. If it is a command, it is a program characterized in that it is determined that the power saving transition condition is not satisfied. With the communication unit that communicates via the USB communication bus,
As a processing unit that controls the communication unit,
Make your computer work
The processing unit
If the power saving transition condition is satisfied when the power saving transition request is received from the host device connected to the communication bus, the power saving transition request is permitted and the communication bus is put into the power saving state. If the transition is performed and the power saving transition condition is not satisfied, the power saving transition request is rejected and the communication bus is not shifted to the power saving state.
The processing unit
When the power saving transition request is a transition request to the power saving state U1, it is determined that the power saving transition condition is satisfied, and when the power saving transition request is a transition request to the power saving state U2. Is a program characterized in that it is determined that the power saving transition condition is not satisfied.

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