JP2005078475A - Data transfer unit - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a data transfer unit, which is mounted on an electronic apparatus driven by a battery, and can transfer a data to another unit by reducing power consumption for transmitting data if the rest of battery power is less than normal. <P>SOLUTION: The data transfer unit mounted on the electronic apparatus driven by the battery comprises a first data transfer means 14 for transferring an input data at high speeds, a second data transfer means 16 for transferring the input data at low speeds, a detecting means 28 for detecting a voltage of the battery to drive the electronic apparatus, and a control means 26, which controls the first and the second data transfer means 14 and 16 based on the voltage detected by the detecting means 28 so that only the data transfer means 14 is activated if the voltage of the battery is more than a predetermined value, and only the data transfer means 16 is activated if the voltage of the battery is less than the predetermined value. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a data transfer apparatus, and more particularly to a data transfer apparatus that switches transfer means having different transfer speeds according to the voltage of an electronic device.

  Patent Document 1 describes a data communication apparatus that processes high-speed communication data communicated at a relatively high speed and low-speed communication data communicated at a relatively low speed. In this data communication apparatus, in particular, when the communication speed is high, the frequency of the operation clock of the data processing CPU is increased, and when the communication speed is low, the frequency of the operation clock of the data processing CPU is decreased. According to this data communication apparatus, the data processing capacity does not become excessive and wasteful power is not consumed, so that it is particularly effective for a battery-driven portable data communication apparatus.

Patent Document 2 describes a data transfer control device that can dynamically switch the frequency of a generated clock without causing a malfunction and can realize data transfer in different transfer modes with low power consumption. ing.
JP-A-7-321874 JP 2002-141911 A

  The above-described conventional apparatus attempts to realize low power consumption by detecting the communication speed and transfer mode on the communication cable and operating at the communication speed and transfer mode according to the state. However, in such a conventional apparatus, the state of the apparatus itself is not taken into consideration. Therefore, in such a conventional device, even when the remaining amount of the battery driving the device is low, data may be transferred with high power consumption, which may spur a decrease in the remaining battery amount.

  In view of this point, the present invention can perform data transfer while reducing the power consumption in the data transfer device when the electronic device provided with the data transfer device is driven by the battery and the remaining amount of the battery is low. An attempt is made to propose a data transfer device that can be used.

  The present invention drives a first transfer means for transferring input data at a high speed, a second transfer means for transferring input data at a low speed, and the electronic apparatus in a data transfer device in an electronic device capable of battery driving. When the battery voltage is equal to or higher than the set value, only the first transfer means is in an operating state, and when the battery voltage is less than the set value, only the second transferring means is in an operating state. As described above, the data transfer apparatus includes a control unit that controls the first and second transfer units based on the detection voltage of the voltage detection unit.

  According to the data transfer device of the present invention, when the battery voltage is equal to or higher than the set value, only the first transfer means is in the operating state, and when it is less than the set value, only the second transfer means is in the operating state. As described above, the control unit controls the first and second transfer units based on the detection voltage of the voltage detection unit. In the data transfer apparatus of the present invention, the data transfer device has detection means for detecting that power is supplied from the AC adapter, and when the detection means detects that power is supplied from the AC adapter, the control means is the first. It is possible to set only the transfer means to the operating state.

  According to the present invention, in a data transfer device in an electronic device that can be driven by a battery, the first transfer unit that transfers input data at high speed, the second transfer unit that transfers input data at low speed, and the electronic device include: When the voltage of the battery to be driven is detected and the battery voltage is equal to or higher than the set value, only the first transfer means is in an operating state, and when it is less than the set value, only the second transfer means is operated. Since it has a control means for controlling the first and second transfer means based on the detection voltage of the voltage detection means so as to be in a state, the electronic device provided with the data transfer device is driven by a battery, When the remaining battery level is low, it is possible to obtain a data transfer device that can perform data transfer while reducing power consumption in the data transfer device. When the battery voltage is less than the predetermined value, the second transfer means, which consumes less power than the first transfer means, is in the operating state, so the first transfer means is in the operating state. Compared with when the first transfer means is in an operating state, the data transfer rate is lower, but the battery remaining capacity decreases less and the battery life is longer. Therefore, when the electronic device provided with the data transfer device is a portable electronic device, it is preferable.

  The configuration of an example of the data transfer apparatus according to the embodiment of the present invention will be described in detail below with reference to FIG. FIG. 1 shows a data transfer device provided in an electronic apparatus. A USB connector is connected to the free end of a USB cable derived from a host computer (not limited to this, various devices, circuits, etc.) not shown, and the USB connector is connected to the illustrated USB connector. It is connected to the connector 18 so that data can be transmitted between the host computer and the electronic device provided with the data transfer device. Note that USB is an abbreviation for Universal Serial Bus, and is one of the standards designed to share the interface of computer peripheral devices.

  Reference numeral 10 denotes a controller as a whole, and the controller 10 detects a connection detection unit (connection detection module) for detecting that a USB connector connected to a free end of a USB cable derived from a host computer is connected to the USB connector 18. 12) A USB 2.0 module 14 for transferring data at high speed and a USB 1.1 module 16 for transferring data at low speed are provided. A USB cable (data communication means) 24 connected to the USB connector 18 is connected to a CPU (Central Processing Unit) 26 through a USB 2.0 module 14 and a USB 1.1 module 16 that are in parallel relation.

  There are two types of data transfer speeds of the USB 1.1 module 16: 12 Mbps (full speed mode) and 1.5 Mbps (low speed mode). The data transfer speed of USB 2.0 is a maximum of 480 Mbps (full speed mode). For this reason, the power consumption of the USB 2.0 module 14 is considerably larger than the power consumption of the USB 1.1 module 16.

  The USB connector 18 is connected to the connection detection means 12 through a USB cable. For example, when a USB connector connected to the free end of a USB cable derived from a host computer is connected to the USB connector 18, an interrupt occurs when this connection is detected by the connection detection means 12. The interruption is transmitted to the CPU 26 through the detection signal transmission path (connection detection notification means) 20. Also, the control signal from the CPU 26 is supplied to the USB 2.0 module 14 and the USB 1.1 module 16 through the control signal transmission path (USB module switching means) 22, and only one of them is controlled to be in an operating state. The

  In an electronic apparatus provided with a data transfer device, an AC adapter is configured such that a battery (battery) 30 can be loaded in a battery housing as a power source, and an AC voltage input terminal is connected to a commercial AC power source. The DC voltage output terminal is configured to be connectable to the DC voltage input terminal. The battery 30 may be a dry battery or a rechargeable battery.

  Voltage detection means (voltage detection module) 28 detects a DC voltage from the battery 30 or a DC voltage from the AC adapter, and the detected voltage is transmitted to the CPU 26 through the detection voltage transmission path 34. . The CPU 26 determines whether the DC voltage from the battery 30 or the DC voltage from the AC adapter is equal to or higher than the set value or less than the set value. When the DC voltage is equal to or higher than the set value, only the USB 2.0 module 14 is operated. When the DC voltage is less than the set value, a control signal for operating only the USB module 1.1 is sent to the USB 2.0 module 14 and the USB 1.1 module 16 through the control signal transmission path 22. I am trying to supply. Note that when the electronic device is driven by the DC voltage from the AC adapter 32, the DC voltage from the AC adapter 32 is equal to or higher than the set value, so that only the USB 2.0 is in an operating state.

  Next, the operation of the data transfer apparatus of FIG. 1 will be described with reference to the block diagram of FIG. 1 together with the flowchart of FIG. First, in step S10, whether or not the USB connector connected to the free end of the USB cable derived from the host computer by the connection detecting means 12 is connected to the USB connector 18, that is, the USB derived from the host computer. It is detected whether or not the cable is connected to the USB cable 24. When the cable is not connected, the process returns to step S10 to be in a standby state, and when connected, the connection detection signal (interrupt) is transmitted to the CPU 26.

  If the determination result in step S10 is “connected”, the process proceeds to step S12, and the CPU 26 determines whether the power supply voltage is equal to or higher than the set value. If the determination result in step S12 is equal to or greater than the set value, the process proceeds to step S16, and the process is started in the high-speed transfer mode. Communication of the USB cable 24 is established.

  If the determination result in step S12 is less than the set value, the process proceeds to step S14, and the process is started in the low-speed transfer mode. That is, only the USB 1.1 module 16 is activated, and then the process proceeds to step S18. Communication of the USB cable 24 is established.

  Next, the configuration of another example of the data transfer apparatus according to the embodiment of the present invention will be described with reference to FIG. 3. In FIG. 3, parts corresponding to those in FIG. The duplicated explanation is omitted. Reference numeral 36 denotes AC adapter detection means as detection means for detecting that power is supplied from the AC adapter. In this example of the data transfer device, for example, the insertion of the plug of the AC adapter 32 into the jack of the electronic device is detected by the AC adapter detection means 36 including a switch that operates by the insertion of the plug, and the detected output is the CPU 26. And control so that only the first transfer means 14 is in an operating state. Other configurations and operations are the same as those in FIG.

It is a block diagram which shows an example of the data transfer apparatus of embodiment of this invention. 3 is a flowchart for explaining the operation of an example of the data transfer apparatus in FIG. 1. It is a block diagram which shows the other example of the data transfer apparatus of embodiment of this invention.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 10 ... Controller, 12 ... Connection detection means (connection detection module), 14 ... USB2.0 module, 16 ... USB1.1 module, 18 ... USB connector, 26 ... CPU, 28 ... Voltage detection means (voltage detection module), 30 ... Battery, 32 ... AC adapter

Claims (3)

In a data transfer device in an electronic device capable of battery driving,
A first transfer means for transferring input data at high speed;
Second transfer means for transferring the input data at a low speed;
Voltage detection means for detecting the voltage of a battery that drives the electronic device;
When the voltage of the battery is equal to or higher than a set value, only the first transfer means is in an operating state, and when it is less than the set value, only the second transfer means is in an operating state. A data transfer apparatus comprising: control means for controlling the first and second transfer means based on a detection voltage of the means. The data transfer device according to claim 1, wherein
Having detection means for detecting that power is supplied from the AC adapter;
The data transfer apparatus according to claim 1, wherein when the detection unit detects that power is supplied from an AC adapter, only the first transfer unit is in an operating state by the control unit. In the data transfer device according to claim 1 or 2,
The first transfer means is a USB 2.0 module,
The data transfer apparatus according to claim 2, wherein the second transfer means is a USB 1.1 module.

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