JP6277866B2 - Charging device and electronic device - Google Patents

Description

  The present invention relates to a charging device that receives a power supply from an external device such as a personal computer (PC) and charges a rechargeable battery, and an electronic device including the charging device.

  For example, Patent Document 1 discloses an example of an electronic device that charges a battery (rechargeable battery) by supplying power from the host device when the USB terminal unit is connected to the host device (an example of the second type device). A mobile phone is disclosed. This cellular phone starts initial processing (enumeration) by transferring data to and from the host device via the USB terminal unit, and charges the battery with the first power. When the initial processing is completed within a predetermined time after the USB terminal unit is connected to the host device, processing based on the initial processing is performed. On the other hand, when the initial processing is not completed within a predetermined time after the USB terminal unit is connected to the host device, the battery is charged with the second power larger than the first power.

  In addition, when a power adapter (an example of the first type device) such as a USB battery charger is connected to the USB terminal unit, the electronic device (device device) charges the battery with power supplied from the power adapter.

JP 2012-203765 A

  By the way, when the electronic device is powered off and connected to the host device via USB, the CPU constituting the control circuit is started up to establish communication with the host device for charging, and is initially connected with the host device. Perform processing (enumeration). When the USB device is connected for the purpose of charging under such a power-off state, the electronic device uses a second power (for example, a current value) larger than the first power (for example, a current value of 100 mA) to the host device in the initial process. The power supply at 500 mA) is requested.

  However, the host device may not be able to supply power with the second power requested from the electronic device. For example, the host device and the electronic device may be connected via a hub that operates on bus power. In this case, even if the electronic device transmits configuration information called a descriptor including a required current value (for example, 500 mA) and class information in the initial processing, the host device can supply power at the second power (current value: 500 mA). Recognize that it is via an impossible hub and do not set its configuration information. For this reason, the initial processing completion notification (setting completion notification) for notifying the setting of the configuration information is not transmitted from the host device to the electronic device. As a result, the electronic device waits for an initial processing completion notification that is not transmitted from the host device, and the CPU is left in an activated state.

  For example, when the host device is driven by a battery, in order to suppress power consumption, there is a case where power supply is permitted only with the third power less than the maximum supply power (for example, a current value of 500 mA). When the second power larger than the third power is requested from the electronic device to the host device of this type, the host device cannot supply power with the second power. In this case, the initial processing is completed from the host device to the electronic device. Notifications are not sent. For this reason, the electronic device waits for an initial processing completion notification that is not transmitted from the host device, and in this case, the CPU is left in an activated state.

  In these cases, power is supplied from the host device through the communication cable with the first power before the initial processing (for example, a guaranteed current value of 100 mA), but the electricity consumed by the CPU of the electronic device is wasted. In particular, if the power consumed by the CPU of the electronic device is larger than the first power while waiting for the notification of completion of the initial process, the remaining amount of the battery gradually decreases. As described above, when the host device cannot supply power to the electronic device with the second power for some reason taking the above two cases as an example, the CPU or the like of the control circuit activated under the power-off state of the electronic device The remaining battery level gradually decreases due to power consumption. Note that the above-described problems are not limited to electronic devices such as mobile phones, but include host devices (external devices) such as printers (including multifunction devices), scanners, projectors, digital cameras (imaging devices), audio devices (acoustic devices), and the like. ) And an electronic device that charges a battery by supplying power from the host device when connected in a power-off state.

  The object of the present invention is to start the control circuit even if the control circuit of the electronic device that is connected to the second type device and started up under the power off state fails in the initial processing with the second type device. An object of the present invention is to provide a charging device and an electronic apparatus that can suppress waste of electricity.

Hereinafter, means for solving the above-described problems and the effects thereof will be described.
A charging device that solves the above problem includes a communication circuit that is connected to an external device to perform communication and receive power supply, a control circuit, and a power switch, and the communication circuit is in an off state when the power switch is off. When connected to an external device, the control circuit is a rechargeable battery using the power received by the communication circuit without performing initial processing if the counterpart to which the communication circuit is connected is the first type device. If the other party to which the communication circuit is connected is the second type device, an initial process is performed. After the initial process is completed, the battery is charged and the communication circuit is connected. If the other party is the second type device and the initial process fails, the battery is not charged.

  According to this configuration, when the communication circuit is connected to an external device while the power switch is off, the control circuit does not perform the initial process if the counterpart to which the communication circuit is connected is the first type device. The rechargeable battery is charged with the power received by the communication circuit. In addition, if the partner to which the communication circuit is connected is the second type device, the control circuit is activated in the power-on state, the initial process is performed, and the battery is charged after the initial process is completed. . On the other hand, when the other party to which the communication circuit is connected is the second type device and the initial process fails, the battery is not charged. That is, when the initial process fails, the control circuit can be turned off from the activated state (power-on state), and the charging of the battery can be stopped before the start of the charging. For this reason, it is possible to suppress the waste of electricity and the reduction of the remaining amount of the battery due to the control circuit being left in the activated state for a long time without completing the initial process. In other words, even if the control circuit of the electronic device that is connected to the second type device and started up under the power-off state fails in the initial processing with the second type device, the waste of electricity due to the activation of the control circuit A decrease in the remaining amount of the battery can be suppressed.

  In the charging apparatus, the control circuit includes a determination circuit that determines a partner to which the communication circuit is connected and a processing circuit that executes at least a part of the initial processing, and the processing circuit operates. In the case where the communication circuit consumes more power than the power received before the initial process, and the communication circuit is connected to an external device while the power switch is off, the determination circuit is If the other party to which the communication circuit is connected is determined to be the first type device, the processing circuit is maintained in a power-off state. If the partner to which the communication circuit is connected is determined to be the second type device, the processing circuit is preferably shifted to a power-on state.

  According to this configuration, when the communication circuit is connected to an external device while the power switch is off, the determination circuit operates based on the power received by the communication circuit before the initial processing and determines the partner to which the communication circuit is connected. . If the partner to which the communication circuit is connected is determined to be the first type device, the processing circuit is maintained in the power-off state, and if the partner to which the communication circuit is connected is determined to be the second type device, the processing circuit To the power-on state. For this reason, when the other party to which the communication circuit is connected is the second type device, the processing circuit that has shifted to the power-on state can perform initial processing with the second type device.

In the charging device, it is preferable that the control circuit determines that the initial processing has failed when a timeout occurs in the initial processing with the second type device.
According to this configuration, the control circuit determines that the initial process has failed when a timeout occurs in the initial process with the second type device. Compared to a configuration that waits until the completion of the initial process without considering the timeout, the power-on time (start-up time) of the control circuit when the initial process is unsuccessful can be shortened. Therefore, it is possible to suppress a situation in which the power of the secondary battery is unnecessarily consumed because the control circuit is left in the power-on state (start-up state) even though the initial process fails and charging is impossible.

In the charging device, it is preferable that the control circuit determines that the initial process has failed because a signal that should be periodically sent from the second type device is not sent.
According to this configuration, the control circuit determines that the initial processing has failed because the signal that should be sent periodically from the second type device is not sent. Therefore, when it is determined that the initial process has failed, the battery can be selected not to be charged, and the control circuit can be turned off. For this reason, it is possible to avoid a situation where the control circuit is left in a power-on state without knowing the failure of the initial processing. Further, for example, the control circuit can be turned off relatively early at the time of the initial process failure as compared with the case where the occurrence of the timeout is determined to be the failure of the initial process. For this reason, the power-on time (start-up time) of the control circuit when the initial process is unsuccessful can be further shortened.

In the charging device, it is preferable that the control circuit sets a time-out time used when determining the time-out as a time required for starting the second type device.
According to this configuration, the control circuit sets the time-out time used when determining the time-out according to the time required for starting the second type device. Therefore, when the other party to which the communication circuit is connected is the second type device, even if the second type device is in the middle of starting, the initial processing with the second type device after the startup is performed. The battery can be charged with the power received by the communication circuit from the second type device.

  Preferably, the charging device includes an operation unit operated for data input, and the control circuit determines that the timeout time used when determining the timeout is set based on the operation of the operation unit. .

  According to this configuration, the timeout time used when the control circuit determines occurrence of timeout is set based on the operation of the operation unit. Therefore, it is possible to set an appropriate time-out period suitable for the user's usage environment (the time required for starting the second type device used). For this reason, since a timeout time that is too short that does not match the time required for starting the second type device is set, charging is performed even though the second type device is determined to have timed out during the start and can be charged. Inconvenience that is not done can be reduced. Therefore, the frequency with which the battery is charged can be increased.

  In the charging device, when the external device connected to the communication circuit is the second type device, the control circuit obtains the time required for starting the second type device, and generates the timeout. It is preferable to set the time-out time used for the determination to a value corresponding to the required startup time.

  According to this configuration, when connected to the second type device, the control circuit acquires the time required for starting the second type device, and sets the time-out time corresponding to the time required for the start. Therefore, it is possible to set an appropriate timeout time suitable for the user's usage environment (the time required for starting the second type device to be used). For this reason, due to the use of a too short time-out time that does not match the time required for starting the second type device, a time-out occurs during the start-up of the second type device. Can be reduced. Therefore, the frequency with which the battery is charged can be increased.

  In the charging apparatus, the control circuit measures a value indicating the remaining amount of the battery or a change in the remaining amount, and fails when the value indicating the change in the remaining amount of the battery or the remaining amount exceeds a threshold value. It is preferable to judge that it was.

  According to this configuration, the control circuit determines the failure of the initial process when the value indicating the remaining amount of the battery or the change in the remaining amount exceeds the threshold value. The failure of the initial process can be determined without monitoring the signal that should be sent from the second type device.

  An electronic device that solves the above problem includes the above-described charging device. According to this structure, the same effect as a charging device can be acquired with an electronic device.

FIG. 2 is a schematic diagram illustrating an electrical configuration of a printer and an external device according to the first embodiment. The sequence diagram at the time of the initial process success of a host apparatus and a printer. The sequence diagram at the time of the initial process failure of a host apparatus and a printer. The flowchart which shows a charge process. FIG. 3 is a schematic diagram illustrating an example in which a host device and a printer are connected by USB via a hub. The flowchart which shows the charge process of 2nd Embodiment.

Hereinafter, an embodiment of a printing system will be described with reference to the drawings.
As shown in FIG. 1, a printer 11 (printing apparatus) as an example of an electronic device functions as a USB device 11A (see FIG. 5) based on the USB (Universal Serial Bus) standard. The printer 11 shown in FIG. 1 has a USB connector 12 to which a connector 35A (terminal) is detachably connected in order to be communicably connected to a host device 30 functioning as a USB host 30A through a communication cable 35 such as a USB cable. I have. The USB connector 12 includes power supply lines (+ −) (P, G) as power supply paths and data lines (D +, D−) for transmitting and receiving data. When the connector 35 </ b> A of the communication cable 35 is connected to the USB connector 12, the same poles of the data line and the power line are connected to each other, and data transmission / reception with the host device 30 and power supply from the host device 30 are possible. The USB connector 12 has an electric circuit for communication including a power line, a data line, various elements (for example, resistors), and the like. In this regard, in this embodiment, the USB connector 12 constitutes an example of a communication circuit.

  The host device 30 is configured by, for example, a personal computer (PC), but may be a computer such as a personal digital assistant (PDA (Personal Digital Assistants)) or a tablet PC as long as it functions as the USB host 30A. Further, the host device 30 may be a printer having a USB host function. The host device 30 includes a USB host 30A and a CPU 30B shown in FIG. At least a part of the software portion of the USB host 30A is constructed, for example, by the CPU 30B executing a USB program. In this embodiment, for example, USB 2.0 is used as the USB standard.

  As shown in FIG. 1, the printer 11 includes a control circuit 13 connected by a USB connector 12, a power supply path 12A, and a data line 12B. The printer 11 includes a secondary battery 14 as an example of a rechargeable battery whose charge is controlled by the control circuit 13, a drive circuit 15 that receives an instruction from the control circuit 13, and a drive circuit 15 according to an instruction from the control circuit 13. And a printing mechanism 16 controlled via the printer.

  As shown in FIG. 1, a connector 40A (terminal) of a charging USB battery charger 40 (power adapter) is detachably connected to the USB connector 12. In addition to the USB connector 12, the printer 11 includes an external power connector 17 for supplying power supplementarily. The external power connector 17 is connected to the control circuit 13 through a power supply path 17A and a data line 17B. A connector 50A (terminal) of an AC adapter 50 (power adapter) is detachably connected to the external power connector 17. The connector 50A of the AC adapter 50 has a cylindrical shape similar to the shape of other general AC adapter connectors. In the present embodiment, the host device 30 and the USB battery charger 40 constitute an example of an external device. The USB battery charger 40 constitutes an example of the first type device, and the host device 30 constitutes an example of the second type device.

  As shown in FIG. 1, an operation panel 19 is provided on the main body 11 a of the printer 11. The operation panel 19 includes an operation switch group 20 that is operated to input various instructions and the like to the printer 11 and a display unit 21 that displays various menus, messages of operation statuses, and the like. The operation switch group 20 is electrically connected to the control circuit 13. The display unit 21 is electrically connected to the control circuit 13 via the display drive circuit 18.

  The operation switch group 20 includes a power switch 20A and an operation switch 20B operated for inputting data by various instruction inputs, selection operations, and the like. By operating the power switch 20A, the printer 11 is turned on and off. That is, the printer 11 switches to the power-on state when the power switch 20A is operated under the power-off state, and switches to the power-off state when the power switch 20A is operated under the power-on state. Further, for example, when the user selects various items by operating the operation switch 20B in the menu displayed on the display unit 21, the control circuit 13 accepts the selection result and sets the printing conditions and the like.

  The control circuit 13 enters the charging mode when the partner to which the USB connector 12 is connected is the host device 30 or the USB battery charger 40 while the printer 11 is turned off. It controls charge control for charging the secondary battery 14 with power supplied through the connector 12. However, if the AC adapter 50 is connected to the external power connector 17 while the printer 11 is powered off, the control circuit 13 gives priority to charging the secondary battery 14 with the power supplied from the AC adapter 50, and the host device 30 or charging based on the power supplied from the USB battery charger 40 is not performed.

  The control circuit 13 also controls print control for printing a document or image based on print job data received from the host device 30 on a print medium such as paper while the printer 11 is powered on. When the AC adapter 50 is connected to the external power connector 17 while the printer 11 is powered on, the printer 11 is operated by the power supplied from the AC adapter 50. Further, the control circuit 13 is in the non-charging mode when the printer 11 in which the AC adapter 50 is not connected to the external power connector 17 is in the power-on state, even if the partner to which the USB connector 12 is connected is the host device 30. The secondary battery 14 is not charged and the printer 11 is operated using the secondary battery 14 as a power source. Further, in the power-on state of the printer 11, even if the other party to which the USB connector 12 is connected is the USB battery charger 40, the control circuit 13 is in the non-charging mode and does not charge the secondary battery 14. The printer 11 is operated with power from the USB battery charger 40.

  The printing mechanism 16 of the present embodiment includes a print head (not shown) that records ink on a print medium such as paper and a transport device (not shown) that transports the print medium. The print head may be a serial system that prints while reciprocating the head in a scanning direction that intersects the conveyance direction of the print medium, or a print head having a length that can be printed at one time in the width direction that intersects the conveyance direction. A line head system for printing on a printing medium conveyed at a constant speed may also be used. Further, the print head method may be any of an ink jet method, a dot impact method, and an electrophotographic method. In addition, in the case of an ink jet system, bubbles are instantaneously generated by using a piezoelectric element or an electrostatic element that generates pressure by bending a pressure plate, or heat, etc., for a driving element that generates pressure for ejecting ink. A bubble element can be used. Further, the printer 11 may receive print job data used for printing at least one of wired and wireless, and may read data used for printing from a storage medium such as a memory card.

  As shown in FIG. 1, the control circuit 13 includes a control IC 22, a power supply circuit 23, a CPU 24, and a memory 25. The control IC 22 is an integrated circuit that performs charge control. The control circuit 13 may include an ASIC (Application Specific IC) in addition to the CPU 24, and the ASIC may control a part of the printing mechanism 16 (for example, a print head).

  The power supply path 12 </ b> A and the data line 12 </ b> B of the USB connector 12 are connected to the control IC 22 in the control circuit 13. The power supply path 17A and the data line 17B of the external power connector 17 are connected to the control IC 22. The control IC 22 has a connection detection function for detecting connection of an external device to each of the connectors 12 and 17 and a determination function for determining the detected connection partner (external device). Further, the control IC 22 performs charge control for the secondary battery 14 in the charge mode, manages the power supply paths 12A and 17A for supplying power to the CPU 24 and the drive circuit 15 and the like, and a data line for transmitting data to the CPU 24 and the like. 12B and 17B are managed.

  The control IC 22 detects the USB connection when either the connector 35A of the communication cable 35 from the host device 30 or the connector 40A of the USB battery charger 40 is connected to the USB connector 12. When the control IC 22 detects the USB connection, for example, when the data line 12B (D +, D−) is (D +) ≠ (D−), the USB connector 12 is connected to the host device 30 that is a computer. On the other hand, if (D +) = (D−), it is determined that the USB connector 12 is connected to the USB battery charger 40. That is, the control IC 22 can determine whether the connection partner (connection destination) connected to the USB connector 12 is the host device 30 or the USB battery charger 40. In this regard, in the present embodiment, the control IC 22 constitutes an example of a determination circuit that determines a connection partner. The control IC 22 may determine the connection partner using another determination method.

  A power supply circuit 23 is interposed in series between the control IC 22 and the CPU 24 in the power supply path 12A. The power supply circuit 23 transforms the input DC voltage as necessary to drive the drive voltage necessary for the control IC 22 and the CPU 24 (for example, a predetermined voltage within a range of 3 to 6 V) and the print head constituting the printing mechanism 16. A necessary drive voltage, a drive voltage necessary for driving a conveyance motor that is a power source of a conveyance device that conveys a print medium such as paper, and the like are generated. The secondary battery 14 is connected to a portion between the control IC 22 and the power supply circuit 23 in the power supply path 12 </ b> A via the first switch 26. The first switch 26 is on / off controlled by the control IC 22. When the first switch 26 is on and conducting, the secondary battery 14 is charged by the power supplied from the power supply path 12A.

  Further, a push-type second switch 27 and a third switch 28 formed of a semiconductor switch are interposed in parallel with each other between the power supply circuit 23 and the CPU 24 in the power supply path 12A. . The push-type second switch 27 is mechanically pressed in conjunction with the operation of the power switch 20A, is turned on only during the operation of the power switch 20A, and is turned off when the operation of the power switch 20A is stopped. A fourth switch 29 is interposed on the power supply path 12 </ b> C connecting the power supply circuit 23 and the drive circuit 15.

  The control IC 22 switches the third switch 28 on (conductive) and off (non-conductive) based on the determination result, and switches on (conductive) and off (non-conductive) a switch (not shown) on the data line 12B. The first switch 26 is controlled to be switched on (conducting) and off (non-conducting).

  The trigger for starting the printer 11 is the push-type second switch 27. When the power switch 20A is pressed and the second switch 27 is turned on under the power-off state of the printer 11, the control IC 22 The third switch 28 is kept on. Specifically, an on signal when the push-type second switch 27 is turned on is input to the CPU 24. When the CPU 24 inputs an ON signal from the second switch 27, the CPU 24 instructs the control IC 22 to switch the printer 11 on and off. When the control IC 22 receives a power supply switching instruction from the CPU 24 while the printer 11 is in a power-off state, the control IC 22 turns on the third switch 28 and the fourth switch 29 and receives a power supply switching instruction from the CPU 24 while the printer 11 is in a power-on state. Then, the third switch 28 and the fourth switch 29 are turned off.

  When the third switch 28 is turned on, necessary power is supplied from the power supply circuit 23 to the CPU 24, and when the third switch 28 is turned off, supply of power from the power supply circuit 23 to the CPU 24 is interrupted. Further, when the fourth switch 29 is turned on, necessary power is supplied from the power supply circuit 23 to the drive circuit 15, and when the fourth switch 29 is turned off, power supply from the power supply circuit 23 to the drive circuit 15 is cut off. Is done. The fourth switch 29 may be configured by a switch group for supplying power by voltage.

  In the power-off state of the printer 11, both the third switch 28 and the fourth switch 29 are in the off state. Further, in this power-off state, if the AC adapter 50 is not connected to the external power connector 17 and neither the host device 30 nor the USB battery charger 40 is connected to the USB connector 12, the first switch 26 is in the off state. It is in.

  When the control IC 22 detects the USB connection to the USB connector 12 in a state where the printer 11 is powered off and the AC adapter 50 is not connected, the connection destination is the host device 30 (USB host 30A). If the secondary battery 14 needs to be charged at that time, the third switch 28 that has been in the off state is turned on. When the third switch 28 is turned on, the control IC 22 activates the CPU 24 in order to execute an initial process called enumeration with the host device 30 prior to charging of the secondary battery 14. At this time, the control IC 22 turns on an internal switch so that the CPU 24 can transmit and receive data through the data line 12B.

  When the USB connector 12 is connected to an external device while the power switch 20A is off, the control IC 22 receives the first power (for example, a guaranteed current value of 100 mA) received by the USB connector 12 before the initial processing together with the secondary battery 14. The other party to which the USB connector 12 is connected as part of the power supply is determined. In addition, the CPU 24 consumes power equal to or higher than the first power received by the USB connector 12 by performing the initial processing. For this reason, when the CPU 24 is left in a standby state in the middle of the initial process without receiving an initial process completion notification from the host device 30, the secondary battery 14 is caused by the power consumption during the startup of the CPU 24 during the standby time. The remaining amount of will be reduced. Here, the guaranteed power is power that must be supplied to a USB connected USB device in the USB standard, and is set to 100 mA in the USB standard, for example.

  In the present embodiment, when the printer 11 is connected to the host device 30 via the USB while the power is off, the CPU 24 is activated to perform initial processing necessary for charging the secondary battery 14. Call it. In addition, turning on the third switch 28 and starting the CPU 24 by the control IC 22 is called “charging start-on”, and turning off the third switch 28 and turning off the activated CPU 24 is called “charging start-off”. There is a case.

  In addition, when the printer 11 is connected to the AC adapter 50 or the USB battery charger 40 under the power-on state, the control IC 22 turns off the first switch 26 and turns on the switches 28 and 29. The CPU 24 and the drive circuit 15 are operated with the power supplied from the power adapter. On the other hand, when the printer 11 is connected to the AC adapter 50 or the USB battery charger 40 with the power off, the control IC 22 turns on the first switch 26 and turns off the switches 28 and 29. The secondary battery 14 is charged with the electric power supplied from the power adapter.

  When the control IC 22 charges the secondary battery 14 with the power from the AC adapter 50 or the USB battery charger 40 when the printer 11 is powered off, the CPU 24 is not activated because it does not need to perform initial processing. The USB battery charger 40 and the AC adapter 50 are not limited to those connected to an AC power outlet, but also include those connected to a DC battery.

  The memory 25 connected to the CPU 24 stores a USB communication program for performing an initial process called enumeration including negotiation of the power supply capability with the host device 30. When connection of the host device 30 to the USB connector 12 is detected, the CPU 24 performs initial processing (enumeration) with the host device 30. In the present embodiment, the CPU 24 executes all of the initial processing, but the CPU 24 may execute a part of the initial processing and the ASIC or the control IC 22 may execute the other part. In the present embodiment, the CPU 24 configures an example of a processing circuit that executes at least a part of the initial processing.

  Further, the CPU 24 shown in FIG. 1 includes a timer 24A. The timer 24A is constituted by a counter in the CPU 24, for example, and functions as a timer by counting clock signal pulses. The CPU 24 causes the timer 24 </ b> A to count the elapsed time from the start of charging as the time T. The memory 25 stores a set timeout time T1 (hereinafter also simply referred to as “timeout time T1”) used when determining whether or not the initial process has failed. When the time T of the timer 24A reaches the timeout time T1 without receiving the initial process completion notification from the host device 30, the CPU 24 instructs the control IC 22 to turn off the charging and turns off the power. , Stop the initial process before starting charging. On the other hand, when the CPU 24 receives the initial processing completion notification from the host device 30 before the time T of the timer 24A reaches the timeout time T1, the CPU 24 instructs the control IC 22 to start charging and turns on the first switch 26. Then, charging of the secondary battery 14 by the power source from the host device 30 is started. Note that the timer 24 </ b> A may be configured by software that performs timing processing by a program, or may be provided in the control IC 22 or ASIC instead of the CPU 24.

  Here, the timeout time T1 is equal to or longer than the BIOS startup time of the host device 30 having the longest BIOS (Basic Input / Output System) startup time among a plurality of types of host devices 30 expected to be used, and this host device. It is set to a value equal to or less than the time required for adding 30 margins to the BIOS startup time. As an example, the timeout time T1 is set to a predetermined value within a range of 30 to 120 seconds. Of course, the time-out time T1 is not limited to the above range, and is associated with the BIOS start time or regardless of the BIOS start time, for example, a shorter time such as 10 seconds or 20 seconds, or 3 minutes or 5 minutes. A longer time can be used.

  Next, referring to FIG. 2 and FIG. 3, enumeration executed as an initial process to establish a communication connection state with the host device 30 under the power-off state of the printer 11 and a timeout process by the timer 24A are involved. The charging process will be described.

  As shown in FIG. 2, when the printer 11 is USB-connected to the host device 30, enumeration is executed as an initial process between the host device 30 that has detected this USB connection and the printer 11.

  As shown in FIG. 2, in the enumeration, first, the printer 11 receives “USB BusReset” instructing reset processing (bus reset) from the host device 30 at the start of enumeration. Next, a “GetDescriptor” requesting configuration information called a descriptor is received. In response to this request, the printer 11 returns printer information as configuration information to the host device 30. The printer information includes class information of the printer 11 and required power value information of power supply requested to the host device 30. Here, when the printer 11 is powered off, the class information is, for example, “human interface device (HID) class”. When the printer 11 is powered on, the class information is “printer class”, for example.

  Further, as the required power value information, a second power larger than the first power (guaranteed power (for example, current value 100 mA)) is set. The required power value information is indicated by required current value information that requests a current value under a predetermined power supply voltage (for example, 5 volts). The requested current value information for requesting the second power is, for example, “500 mA” corresponding to the maximum power that can be supplied by the USB standard. The second power is not limited to the maximum power, but may be any power that can charge the secondary battery 14, and may be a power that is larger than the first power and less than the maximum power.

  Then, the host device 30 recognizes that the USB device connected by USB based on the class information (for example, “HID”) is a human interface device. Further, the host device 30 determines whether or not power supply with the requested second power is possible based on the requested current value information (for example, 500 mA), and power supply with the second power is possible. If so, the printer information is set and “SetConfiguration” which is an initial processing completion notification (setting completion notification) is transmitted to the printer 11.

  As shown in FIG. 2, charging is not possible until the power supply with the second power requested from the printer 11 in the enumeration is permitted and the initial processing completion notification “SetConfiguration” is received. When the initial processing completion notification is received, the secondary battery 14 can be charged by being supplied with the second power requested from the host device 30 to the printer 11.

  In this embodiment, when the USB device is detected when the printer 11 is powered off and the AC adapter 50 is not connected, the CPU 24 in the printer 11 is activated when the connection partner is the host device 30. (Charge start-up is on). At substantially the same time as the start of charging of the CPU 24, the CPU 24 starts measuring time by the timer 24A. The CPU 24 measures the elapsed time from the activation time by the timer 24A, and determines whether or not the time T has reached the timeout time T1. If the initial processing completion notification “SetConfiguration” is received before the time T reaches the timeout time T1, power supply at the second power (for example, 500 mA in current value) is started from the host device 30. The secondary battery 14 is charged with the second electric power.

  On the other hand, as shown in FIG. 3, the printer information transmitted by the printer 11 in the initial process started when the USB connection between the printer 11 and the host device 30 is detected and the CPU 24 in the printer 11 is activated (charging activation is turned on). Is not permitted by the host device 30, the printer 11 cannot receive the initial processing completion notification “SetConfiguration”. In this case, in the printer 11, the time T of the timer 24A reaches the timeout time T1 without receiving the initial process completion notification. As described above, when the time T reaches the timeout time T1 without receiving the initial process completion notification “SetConfiguration”, the printer 11 turns off the power of the CPU 24 that is internally turned on for the purpose of charging. , Turn off charging start (power off).

  Here, as an example in which the initial processing completion notification cannot be received even after the time-out period T1 has elapsed, the following cases may be mentioned. For example, as shown in FIG. 5, in a configuration in which the host device 30 and the printer 11 are connected via a hub 60 (branch device) operating with bus power, the port 60a of the hub 60 is, for example, an N port ( In the example of FIG. 5, power can be supplied only at a current value of 500 / N (mA) per port (100 mA in the example of FIG. 5). Therefore, even if the printer 11 transmits printer information including class information and requested current value information (for example, 500 mA), the host device 30 recognizes that it is via a hub and uses the second power (for example, 500 mA for the current value). It is determined that the power cannot be supplied. For this reason, since the host apparatus 30 cannot permit the power supply with the requested second power, the printer information is not set. As a result, as illustrated in FIG. 3, the host device 30 does not transmit the initial processing completion notification “SetConfiguration” to the printer 11. For this reason, the printer 11 enters a standby state waiting for reception of the initial processing completion notification “SetConfiguration” that is not transmitted from the host device 30.

  In some cases, the host device 30 is set to limit power supply to the USB device (printer 11) to a predetermined power less than the maximum power (for example, a current value of 500 mA) when the battery is driven. In such a host device 30, the power supply with the second power requested from the printer 11 cannot be performed, and thus the initial processing completion notification “SetConfiguration” is not transmitted from the host device 30 to the printer 11. Also in this case, the printer 11 is in a standby state waiting for reception of an initial processing completion notification “SetConfiguration” that is not transmitted from the host device 30.

  In this standby state, the CPU 24 waits in an activated state (charging activation on state), and thus consumes the power of the secondary battery 14. In this standby state, the printer 11 receives power supply from the host device 30 through the communication cable 35 with the first power (current value is, for example, 100 mA). However, the power consumed by the activated CPU 24 in the initial process exceeds the first power. Therefore, the remaining amount of the secondary battery 14 gradually decreases as the standby time elapses.

  Therefore, in the present embodiment, the above-described timeout time T1 is set, and when the measured time T reaches the timeout time T1 and times out without receiving the initial processing completion notification, it is included in the printer information responding to the host device 30. Assuming that the request is not permitted and the initial process has failed, the CPU 24 turns off the power (charge activation off). The timeout time T1 is set to a value corresponding to the longest BIOS startup time among a plurality of types of host devices 30 that are assumed to be connected to the USB connector 12, and the host device 30 waits for BIOS startup. It will time out after waiting for almost enough time. For this reason, the timeout time T1 is set to easily avoid the inconvenience that the secondary battery 14 cannot be charged due to a timeout due to a timeout time that is too short even if the battery can be charged.

  Further, the printer 11 stores a charging processing program shown in the flowchart of FIG. This program includes a part written in the control IC 22 (steps S11 to S16) and a part stored in the memory 25 and executed by the CPU 24 (steps S17 to S23).

  Next, the operation of the printer 11 will be described with reference to FIG. That is, a charging process executed by the control IC 22 and the CPU 24 in the printer 11 will be described. The charging process illustrated in FIG. 4 is performed in a state where the printer 11 is in a power-off state and the AC adapter 50 is not connected and the secondary battery 14 is not charged by the AC adapter 50. When any connector is connected to the USB connector 12 and the USB connection is detected, the charging process program shown in FIG. 4 is executed.

First, in step S11, the control IC is activated.
In the next step S12, it is determined whether or not the connection destination is a host device. That is, the control IC 22 determines whether the connection destination is the host device 30 that functions as the USB host 30A or a power adapter such as the USB battery charger 40. For example, when the data line is (D +) ≠ (D−), it is determined that the connection destination is the host device 30, and when (D +) = (D−), it is determined that the connection destination is the power adapter. . If the connection destination is not the host device 30 but the power adapter, the process proceeds to step S13. If the connection destination is the host apparatus 30, the process proceeds to step S14.

In step S13, charging is started with the power adapter. In this example, the secondary battery 14 is charged with power from the USB battery charger 40.
In step S14, it is determined whether or not the remaining amount of the secondary battery is less than a threshold value. That is, it is determined whether or not the remaining amount of the secondary battery 14 is less than a threshold value that is sufficient for performing the initial process. If the remaining amount of the secondary battery 14 is less than the threshold value, the process proceeds to step S15, and if not, the process proceeds to step S16.

  In step S15, the secondary battery is charged with the first power (for example, 100 mA). In the USB standard, power supply with the first power is guaranteed, so the secondary battery 14 is charged with the first power until the remaining amount reaches a threshold value. And if the secondary battery 14 is charged until the remaining amount becomes more than a threshold value (it is negative determination by S14), it will progress to step S16.

  In step S16, the CPU is activated (charging activation is on). That is, the control IC 22 activates the CPU 24 by switching the third switch 28 from off to on. In this way, the CPU 24 is activated in order to perform necessary initial processing with the host device 30 before starting the charging of the secondary battery 14.

  In step S17, the timer starts counting. That is, the CPU 24 starts measuring the timer 24A. As a result, the timer 24 </ b> A measures the elapsed time (timed time T) from the activation point of the CPU 24.

  In the next step S18, pull-up is performed. That is, the CPU 24 performs pull-up by changing the voltages of the data lines D + and D−. By this pull-up, the host device 30 detects the connection of the USB device 11A (printer 11) and starts an initial process (enumeration) (see FIGS. 2 and 3). It should be noted that the processing order of the timing start process (S17) and the pull-up process (S18) by the timer 24A may be reversed.

  In step S19, initial processing is performed, and printer information is transmitted in response to a request from the host device 30. The printer information includes class information and required power information. In the printer 11 of this example, the required power information is set to the second power (for example, 500 mA in current value) in the charging mode. For this reason, the printer 11 requests the second power from the host device 30 through the printer information.

  As shown in FIG. 2, when USB connection is detected by pull-up, enumeration is performed as an initial process between the host device 30 and the printer 11. That is, first, “USB BusReset” for instructing bus reset to the printer 11 is transmitted from the host device 30, and then “GetDescriptor” for requesting configuration information (descriptor) is transmitted. The printer 11 that has received “GetDescriptor” transmits printer information including class information (for example, “HID”) and requested power information (second power) as configuration information.

  When the host device 30 can supply power to the printer 11 with the second power, an initial processing completion notification “SetConfiguration” is transmitted from the host device 30 to the printer 11 as shown in FIG.

  On the other hand, as shown in FIG. 5, when the host device 30 and the printer 11 are connected via a bus power hub, the printer 11 transmits printer information including class information and required power information (second power). However, the host device 30 does not permit the power supply with the requested second power because it recognizes that it is via the hub. Therefore, as shown in FIG. 3, the initial processing completion notification “SetConfiguration” is not transmitted from the host device 30. Therefore, the printer 11 waits in the activated state for the initial processing completion notification “SetConfiguration” that is not transmitted from the host device 30. During this standby, the power of the secondary battery 14 is consumed by the CPU 24 that is being activated (charging activation is on).

  Further, when the host device 30 is set to limit the power supplied to the USB device 11A to a predetermined power less than the maximum power (500 mA in current value) when the battery is driven, the second power requested from the printer 11 ( The power cannot be supplied at a current value of 500 mA). For this reason, the initial processing completion notification “SetConfiguration” is not transmitted from the host device 30 to the printer 11. Also in this case, the CPU 24 in the printer 11 waits for the initial processing completion notification “SetConfiguration” that is not transmitted from the host device 30 in the activated state. During this standby, the power of the secondary battery 14 is consumed by the activated CPU 24. In these cases, when the first power (100 mA in current value) is supplied from the host device 30 through the communication cable 35, but the power consumed by the starting CPU 24 in the initial process exceeds the first power, the secondary battery 14 The remaining amount of will gradually decrease.

  In step S20, it is determined whether an initial processing completion notification has been received. Here, the host device 30 determines whether or not the power supply with the second power requested in the printer information (configuration information) received in the initial process can be permitted, and if so, sets the printer information. Then, an initial processing completion notification “SetConfiguration” is transmitted to the printer 11. Then, the CPU 24 proceeds to step S21 if it does not receive the initial process completion notification, and proceeds to step S22 if it is received.

  If the initial process completion notification is not received, it is determined in step S21 whether a timeout has occurred. That is, it is determined whether or not the time T of the timer 24A has reached the timeout time T1. If not timed out, the process returns to step S20. That is, the processes in steps S20 and S21 are repeated until an initial process completion notification is received (affirmative determination in S20) or a timeout occurs (positive determination in S21).

In step S22, the battery is charged with the second power (current value is 500 mA). That is, the secondary battery 14 is charged with the second power supplied from the host device 30.
On the other hand, if a time-out has occurred (Yes in S21), the CPU 24 and the control IC 22 are turned off (charge activation off) in step S23. That is, when the time T, which is the elapsed time from the time of starting the CPU, reaches the time-out time T1, both the CPU 24 and the control IC 22 in the activated state are turned off, and the charging of the secondary battery 14 is stopped before the start. (Charging start off) For example, in accordance with an off instruction from the CPU 24, the control IC 22 turns off the power of the CPU 24 by turning off the third switch 28, and then turns off its own power. During charging after the secondary battery 14 is started to be charged in steps S13 and S22, the control IC 22 monitors the remaining amount of the secondary battery 14, and when the secondary battery 14 is fully charged, the first switch 26 is turned on. By turning off, the charging of the secondary battery 14 is terminated.

According to the embodiment described in detail above, the following effects can be obtained.
(1) If the power switch 20A is off and the USB connector 12 is connected to the USB battery charger 40 (an example of the first type device), the control circuit 13 performs initial processing (enumeration). Instead, the secondary battery 14 is charged with the power received by the USB connector 12. Further, if the other party to which the USB connector 12 is connected is the host device 30 (an example of the second type device), the control circuit 13 performs an initial process and charges the secondary battery 14 after the initial process is completed. To do. On the other hand, when the other party to which the USB connector 12 is connected is the host device 30 and the initial process fails, the secondary battery 14 is not charged. Therefore, when the power switch 20A is off and the USB connector 12 is connected to the host device 30 and the initialization process fails, the control circuit 13 (especially the CPU 24) can be turned off, and the battery 14 can be stopped before it starts. For this reason, even if the initial process fails, it is possible to suppress waste of electricity and reduction of the remaining amount of the battery 14 due to the control circuit 13 being left in the activated state for a long time.

  (2) The control circuit 13 includes a control IC 22 (an example of a determination circuit) that determines a partner to which the USB connector 12 is connected, and a CPU 24 (an example of a processing circuit) that executes at least a part of the initial processing. If it is determined that the other party to which the USB connector 12 is connected is the USB battery charger 40 (an example of the first type device), the CPU 24 is maintained in a power-off state. If it is determined that the other party to which the USB connector 12 is connected is the host device 30 (an example of the second type device), the CPU 24 is shifted to the power-on state. Therefore, the CPU 24 that has shifted to the power-on state can perform initial processing with the host device 30.

  (3) The control circuit 13 determines that the initial process has failed when a timeout occurs in the initial process with the host device 30. For this reason, the startup time (power-on time) of the control circuit 13 when the initial process is unsuccessful can be shortened as compared with the case where the configuration waits until the initial process completion notification is received without considering the timeout. it can. Therefore, it is possible to suppress the situation where the control circuit 13 is left in the activated state (power-on state) and the power of the secondary battery 14 is unnecessarily consumed although the initial process fails and charging is impossible.

  (4) The control circuit 13 sets the timeout time T1 used when determining the timeout, according to the BIOS startup required time (an example of the startup required time) of the host device 30. Therefore, even when the host device 30 to which the USB connector 12 is connected is in the middle of starting, the second power (for example, current) is supplied by supplying power from the host device 30 after performing initial processing with the host device 30 after the startup. The secondary battery 14 can be charged at a value of 500 mA).

  (5) In particular, the timeout time T1 is set by adding a predetermined margin time to the longest time required for starting up a plurality of types of host devices 30 to be connected. Therefore, it is possible to suppress the situation where the secondary battery 14 cannot be charged as much as possible because it is determined that the initial process has failed due to the occurrence of a timeout during the startup of the host device 30 due to the too short timeout time even though the battery can be charged. For this reason, the frequency with which the secondary battery 14 is charged can be relatively increased.

(Second Embodiment)
Next, a second embodiment will be described with reference to FIG. In this embodiment, the activation of the CPU 24 is turned off by another method in addition to the timeout. The configuration of the printer 11 is the same as that of the first embodiment, and only a part of the charging process executed by the CPU 24 is different. Therefore, the same reference numerals are used for the same configuration and the same processing as those of the first embodiment. The description will be omitted, and only different parts will be described.

  In the present embodiment, the failure of the initial process is determined by the occurrence of a timeout similar to that in the first embodiment and the transition of the host device 30 to the suspended state (temporary suspension state). Depending on the type of the host device 30, an SOF (start of frame) signal is transmitted to the printer 11 periodically (for example, every predetermined time of less than 1 millisecond) during USB connection. The SOF signal is a signal transmitted from the host device 30 to the printer 11 at intervals of a predetermined time To within a range of 10 microseconds to 1 millisecond, for example.

  For this reason, the SOF signal is transmitted from the host device 30 to the printer 11 even during the initial processing. When the host device 30 cannot permit the required power information (second power) included in the printer information (configuration information) received from the printer 11 in the initial process, the host device 30 does not set the printer information and shifts to the suspended state. . By shifting to the suspended state, the host device 30 stops transmitting the SOF signal.

  When the SOF signal that should have been sent from the host device 30 during the USB connection with the host device 30 is interrupted, the CPU 24 that constitutes the control circuit 13 in the printer 11 stops the host device 30 from being suspended. Transition is made, and it is considered that the initial process has failed, and the activation of the CPU 24 and the like is turned off (charge activation off). In this example, when the SOF signal that should be sent from the host device 30 is not sent for the second set time T2, the CPU 24 considers that the host device 30 has shifted to the suspended state, and the CPU 24 Turn off the power (charging start off). The second set time T2 is set to, for example, a certain time that satisfies T2> To in a range of 1 to 10 milliseconds. That is, it is determined that the initial process has failed when the SOF signal stops and becomes idle for the second set time T2.

Next, the operation of the printer 11 of the present embodiment will be described with reference to FIG. In the first embodiment, the processes in steps S11 to S18 shown in FIG. 4 are the same in this embodiment.
In step S19, initial processing is performed, and printer information including class information (for example, “HID”) and requested power information (second power (current value: 500 mA)) is transmitted in response to a request from the host device 30. .

  In step S20, it is determined whether an initial processing completion notification has been received. Here, the host device 30 determines whether or not the power supply with the second power requested in the printer information (configuration information) received in the initial process can be permitted, and if so, sets the printer information. At the same time, an initial processing completion notification “SetConfiguration” is transmitted to the printer 11. Then, the CPU 24 of the printer 11 proceeds to step S21 if the initial processing completion notification is not received, and proceeds to step S22 if received.

  If the initial processing completion notification is not received (No in S20), it is determined in step S21 whether a timeout has occurred. That is, it is determined whether or not the time T of the timer 24A has reached the timeout time T1. If not timed out, the process proceeds to step S31.

  In step S31, it is determined whether or not the SOF signal is received for the second set time T2 or longer. That is, the CPU 24 determines whether or not the reception of the SOF signal that should have been sent from the host device 30 during the USB connection has been idle for a second set time T2 or longer. If the idle state where the reception of the SOF signal is interrupted does not reach the second set time T2, the process returns to step S20, and if the idle state continues for the second set time T2 or more, the process proceeds to step S23.

  In this way, any one of the determination processes is established as to whether the initial process completion notification is received (Yes in S20), the time-out occurs (Yes in S21), or whether the SOF signal is received for the second set time or more. Until it does, each processing of step S20, S21 and S31 is repeated.

  If the reception of the SOF signal is not interrupted for the second set time T2 or longer (No determination in S31) and if the initial process completion notification is received, the process proceeds to step S22 and the secondary battery 14 is charged with the second power.

  On the other hand, if the idle state in which the SOF signal that should be periodically sent from the host device 30 is interrupted during the USB connection continues for the second set time T2 or more (affirmative determination in S31), it is regarded as a failure of the initial process, and the step Proceeding to S23, the CPU 24 and the control IC 22 are turned off (charging start-off). In this case, the CPU 24 detects (determines) the failure of the initial process almost in real time without waiting for the elapse of the timeout time T1 from the start point, turns off the power of the CPU 24 and the control IC 22, and cancels the initial process before starting the charging To do.

  When the host device 30 does not transmit the SOF signal and the host device 30 cannot permit the power supply with the second power, the CPU 24 of the printer 11 does not receive the initial processing completion notification, and the time measurement time T is the timeout time. T1 is reached (affirmative determination in S21). In this case, in step S23, the power of the CPU 24 and the control IC 22 is turned off (charging start-off).

According to the second embodiment, the same effects as those of the first embodiment can be obtained, and the following effects can be further obtained.
(6) When the CPU 24 of the printer 11 stops receiving the SOF signal that should be sent periodically from the host device 30 during the USB connection and stops for the second set time T2, the power of the CPU 24 and the control IC 22 is turned off. Turn off. That is, when the SOF signal is not received for the second set time T2, it is determined that the initial process has failed, the power of the CPU 24 and the control IC 22 can be turned off, and the charging of the secondary battery 14 can be stopped. For this reason, it is possible to avoid a situation in which the control circuit 13 is left in a power-on state without knowing the failure of the initial process.

  (7) The CPU 24 and the control IC 22 can be shifted to the power-off state almost in real time when the initial process fails without waiting for the timeout time T1 from the time when the CPU 24 is activated. For this reason, the power-on time (start-up time) of the control circuit 13 when the initial process is unsuccessful can be shortened, and the remaining amount of the secondary battery 14 due to the control circuit 13 being left in the start-up state can be reduced. Reduction can be further suppressed.

In addition, each said embodiment can also be changed into the following forms, or can also combine these.
-You may enable it to change timeout time according to a user's operating environment. An operation switch 20B as an example of an operation unit operated for data input is provided, and the control circuit 13 may be configured to set a timeout time T1 used when determining a timeout based on the operation of the operation switch 20B. Good. In this case, the timeout time T1 may be input and set as a numerical value by operating the operation switch 20B, or a desired one may be selected from the options of the timeout time T1. According to this configuration, it is possible for the user to set an appropriate timeout time T1 suitable for the usage environment based on the operation of the operation switch 20B. Therefore, since the timeout time that is too short that does not match the BIOS startup time of the host device 30 to be used is set in an unchangeable state, the host device 30 is determined to time out during startup even though it can be charged. Inconvenience that the battery is not charged can be reduced. As a result, the frequency with which the secondary battery 14 is charged can be increased.

  Although the timeout time T1 is a constant value, it may be variable. When the partner to which the USB connector 12 is connected is the host device 30 which is an example of the second type device, the control circuit 13 acquires the required start time information from the host device 30 or the host device 30 The required start time may be obtained by counting with a timer in the control circuit 13, and the timeout time T1 may be set according to the acquired required start time. According to this configuration, the control circuit 13 can set the timeout time T1 according to the acquired required startup time, and thus can set an appropriate timeout time T1 suitable for the use environment of the user. For this reason, since a timeout time that is too short that does not match the required startup time of the host device 30 is set, it is determined that a timeout has occurred during the startup of the host device 30, and charging is not performed despite being able to be charged. Can be reduced. As a result, the frequency with which the battery 14 is charged can be increased. In addition, the control circuit 13 stores the data of the maximum M required startup times in the memory 25, and erases the oldest data among the past data exceeding M each time a new startup required time is acquired. A timeout time is set according to the longest required startup time among the M. In addition, data exceeding the preset maximum set time among the past M pieces is not adopted, and the timeout time T1 is set according to the longest required start time among the data of the required start time less than the maximum set time. Good. With these configurations, since the host device 30 that happens to have a very long startup time is connected to the printer 11 only once, an excessively long timeout time based on the very long startup time of the host device 30 is set. It is possible to set an appropriate timeout time T1 while avoiding this.

  The control circuit 13 measures a value indicating the remaining amount of the secondary battery 14 or a change in the remaining amount, and if the value indicating the remaining amount of the secondary battery 14 or the change in the remaining amount exceeds a threshold value, the initial process fails. You may judge that you did. In this case, the value indicating the change in the remaining amount of the secondary battery may be a change amount or a change rate. According to this configuration, the control circuit 13 determines that the initial process has failed when a value indicating the remaining amount of the secondary battery 14 or a change in the remaining amount (for example, a change amount or a change rate) exceeds a threshold value. . For this reason, it is possible to determine the failure of the initial process without using a timer such as a timer. Further, when the remaining rate of change is used, when the remaining amount of the secondary battery 14 is relatively small, it is determined that the initial process has failed relatively early, and the remaining amount of the secondary battery 14 is relatively If there are many, it is determined that the initial processing has failed relatively late. For this reason, although the remaining amount of the secondary battery 14 is small, it is easy to avoid a situation where the determination of the failure of the initial process is delayed and the remaining amount becomes extremely small. Further, when the timeout time T1 is set according to the remaining amount of the secondary battery 14, for example, when the remaining amount of the secondary battery 14 is less than the threshold, the timeout time T1 is set relatively short, and the remaining amount is If there are many, the timeout time T1 may be set relatively long.

  The timeout time T1 is preferably set to a value corresponding to the longest startup required time (BIOS startup required time) among a plurality of types of host devices 30 that are assumed to be connected. The same time or a time shorter than the BIOS startup time may be set. For example, it may be 1/2 or 1/3 of the BIOS startup time. Moreover, you may set timeout time T1 which does not consider BIOS starting required time. For example, the timeout time T1 may be set to a value not less than the enumeration required time and not more than a time obtained by adding a predetermined margin time (for example, 1 to 10 seconds) to the enumeration required time.

  The timing for starting the timing T is not limited to the time when the CPU is activated (the time when charging is activated). For example, the timer 24A may start timing at the time of USB connection (for example, when USB connection is detected). In this case, for example, if the time is measured by a timer (for example, a counter) in the control IC 22, the time can be started even before the CPU is activated. Alternatively, the timer may be started when a predetermined time elapses from the CPU activation time. For example, the time measurement by the timer may be started from the transmission time point of the printer information (configuration information).

  In the second embodiment, if it is assumed that the host device 30 periodically transmits an SOF signal to the USB device 11A during USB connection, it is determined whether or not a timeout has occurred in the flowchart shown in FIG. The process (S22) may be abolished.

  The USB standard is not limited to USB 2.0, but may be applied to USB 3.0 and USB 3.1. Moreover, you may apply to USB1.0 or USB1.1. Further, the present invention is not limited to the USB standard, and may be applied to other communication standards. In short, the initial processing is performed between the host device and the electronic device, and the initial processing is completed by receiving the initial processing completion notification (notification corresponding to “Set Configuration” of the USB standard) as a trigger. Any other communication standard may be used as long as it is configured to receive power necessary for charging from the host device upon completion. For example, IEEE1394, SCSI, or ATA may be used. The communication method is not limited to the wired communication method, and may be a wireless communication method as long as power can be supplied from the host device to the electronic device.

  The power switch 20A is not limited to the push type, and may be a toggle type. In addition, any switch that can be operated so as to be able to switch the power on and off may be used. Further, a sensor type power switch may be used, and a contact sensor type or non-contact sensor type power switch may be used.

  The control circuit is configured to include a control IC 22 configured by hardware and software by a CPU that executes a program. However, the control circuit may be realized by hardware using an electronic circuit such as the control IC 22 or ASIC, or only by software. It may be realized.

  The printer (printing apparatus) is not limited to a dedicated printing machine, but may be a multifunction machine having a copy function and a scanner function. Furthermore, the printer may be any of a page printer in addition to a serial printer and a line printer. The printer may be a portable type, a small size, a medium size printer, or a large size printer. For example, a business printer or a large format printer may be used.

  The electronic device is not limited to a printer (including a multifunction device) but may be a scanner, a projector, a digital camera (imaging device), a digital audio device (acoustic device), or the like.

  DESCRIPTION OF SYMBOLS 11 ... Printer as an example of an electronic device, 12 ... USB connector as an example of a communication circuit, 13 ... Control circuit, 14 ... Secondary battery as an example of a rechargeable battery, 15 ... Drive circuit, 16 ... Printing mechanism, 20A ... Power switch, 20B ... Operation switch as an example of an operation unit, 22 ... Control IC as an example of a determination circuit, 23 ... Power supply circuit, 24 ... CPU as an example of a processing circuit, 25 ... Memory, 26 ... First Switch, 30 ... host device as an example of external device and second type device, 35 ... communication cable, 40 ... USB battery charger as an example of external device and first type device, T1 ... as an example of timeout time Setting timeout time, T2 ... second setting time.

Claims (9)

A communication circuit connected to an external device for communication and receiving power supply;
A control circuit;
A power switch, and
When the communication circuit is connected to an external device in a state where the power switch is off, the control circuit can perform the initial processing without performing initial processing if the counterpart to which the communication circuit is connected is the first type device. Charge the rechargeable battery with the power received by the communication circuit,
If the other party to which the communication circuit is connected is a second type device, perform an initial process, and after completing the initial process, charge the battery,
The charging device is characterized in that the battery connected to the communication circuit is a second type device, and the battery is not charged when the initial process fails. The control circuit includes a determination circuit that determines a partner to which the communication circuit is connected, and a processing circuit that executes at least a part of the initial processing.
When the processing circuit operates, consume more power than the power received by the communication circuit before initial processing,
When the communication circuit is connected to an external device when the power switch is off,
The determination circuit is operated by the power received by the communication circuit before initial processing to determine a partner to which the communication circuit is connected,
If the partner to which the communication circuit is connected is determined to be the first type device, the processing circuit is maintained in a power-off state,
2. The charging device according to claim 1, wherein if the counterpart to which the communication circuit is connected is determined to be a second type device, the processing circuit is shifted to a power-on state.   The charging device according to claim 1, wherein the control circuit determines that the initial process has failed when a timeout occurs in the initial process with the second type device.   3. The control circuit according to claim 1, wherein the control circuit determines that the initial processing has failed because a signal that should be periodically transmitted from the second type device is not transmitted. The charging device described.   4. The charging device according to claim 3, wherein the control circuit sets a timeout time used when determining the timeout as a time required for starting the second type of device. 5. It has an operation unit that is operated to input data,
6. The charging device according to claim 3, wherein a timeout time used when the control circuit determines occurrence of the timeout is set based on an operation of the operation unit.   When the external device connected to the communication circuit is the second type device, the control circuit acquires a time required for starting the second type device and uses it to determine the occurrence of the timeout. 6. The charging device according to claim 3, wherein a timeout time is set to a value corresponding to the required startup time.   The control circuit measures a value indicating the remaining amount of the battery or a change in the remaining amount, and determines that the initial process has failed when the value indicating the remaining amount of the battery or the change in the remaining amount exceeds a threshold value. The charging device according to claim 1, wherein:   An electronic apparatus comprising the charging device according to any one of claims 1 to 8.