1. Field of the Invention
The present invention generally relates to a data transmitting device and system, and more particularly to a data transmitting device and system for communicating with a portable device and method thereof.
2. Description of Related Art
Hand-held devices or portable devices, such as a USB device, not only can be used to transfer data, but also can be used to perform charging by plugging the device in the interface connecting port (e.g., USB connecting port) of a computer. However, this has the limitation of the number of USB devices communicating with the USB connecting port of the computer. In order to communicate with the computer for more hand-held devices, the USB hub is developed to connect the hand-held devices and the computer.
Referring now to
Although the host computer 11 can connect plural portable devices 15 at the same time based on the scheme in
In view of the above drawbacks, a need has arisen to propose a novel data transmitting system for portable device and method thereof to save power consumption and design cost.
In view of the foregoing, it is an object of the embodiment of the present invention to provide a data transmitting device and system and method for communicating a portable device with a host computer, which utilizes switch circuit to switch data transmitting path, so as to simplify the control mechanism for the communication between a USB interface of the host computer and the USB portable devices.
According to one embodiment, a data transmitting device is provided. The data transmitting device includes a first USB connector, at least one second USB connector and a first portable device. The first USB connector is used to connect with a host computer. The first portable device, coupling with the first USB connector and the second USB connector, includes a switch circuit and a switch. The switch is configured to generate a control signal to the switch circuit, so as to connect the data transmission path between the first portable device and the host computer or connect the data transmission path between the second USB connector and the host computer.
According to another embodiment, a data transmitting system for communicating with one of USB portable devices is provided. The data transmitting system includes a data transmitting device and a first portable device. The data transmitting device includes a first USB connector, used to connect with a host computer, and at least one second USB connector. The first portable device, coupled with the data transmitting device, includes a first switch circuit and a first switch. The first switch configured to generate a first control signal to the first switch circuit, so as to connect or disconnect the data transmission path between the first portable device and the host computer.
According to another embodiment, a data transmitting method for communicating one of a plurality of portable devices with a host computer via a data transmitting device having a plurality of USB connectors is disclosed. The method comprises the following steps: firstly, a switch circuit is configured in each of the portable devices. Then, at least one of the portable devices is coupled to the host computer by connecting the at least one of the portable devices to one of the USB connectors of the data transmitting device. Afterward, at least one data transmission path between the host computer and the portable devices is connected by the switch circuits of the portable devices. Data between the portable device and the host computer is transmitted when only one data transmission path between the host computer and the portable device is connected by the switch circuit of the portable device. The USB connectors of the data transmitting device could be the USB host connectors, the USB device connectors or the combination thereof.
According to another embodiment, a data transmitting method for communicating one of a plurality of portable devices with a host computer via a data transmitting device having a plurality of USB connectors is disclosed. The method comprises the following steps: firstly, a switch circuit is configured in one of the portable devices. Then, the portable device having the switch circuit is coupled with the data transmitting device. Afterward, a data transmission path between the host computer and the portable device having the switch circuit is connected by the switch circuit to transmit data between the portable device having the switch circuit and the host computer, or the data transmission path between the USB connector, which is not connecting with the portable device having the switch circuit, and the host computer is connected by the switch circuit.
Referring now to
Please refer to
Each of the portable devices 25, such as the (first) portable device 25a for example, comprises a switch circuit 252a and a switch 251. The switch circuit 252a is configured in portable device 25a. When turning on the portable device 25a and other portable devices are turned off) by switching the switch 251 of the portable device 25a, the switch 251 generates a control signal (Ctrl_a) to close the switch circuit 252a, so as to connect the data transmission path (via the differential data pins 2113, 2115) between the portable 25a device and the host computer 21 and obtain electricity provided by the host computer 21 via the voltage pin 2111. Similarly, the (second) portable device 25b or other portable device, which is parallel coupled with the data transmitting device 23 directly or via the USB connector 233, also has the same control circuit to switch voltage and differential data lines. That is, the (second) portable device 25b communicates with the host computer 21 when the data transmission path between the portable device 25a and the host computer 21 is disconnected, and the switch circuit 252b receives the control signal (Ctrl_b) to connect the data transmission path between the second portable device 25b and the host computer 21. There is only one of the portable devices 25 turned on at the same time, and other portable devices 25 must enter into off-line state.
In one embodiment, the switch circuit 252a comprises a PMOS transistor or a NMOS transistor. As shown in
Referring now to
Please refer to
The data transmitting system of the present invention allows only one portable device 25 to communicate with the host computer at a time. In one embodiment, the data transmitting device further comprises a multiplexer configured to selectively couple the first portable device 25a or the second portable device 25b with the host computer 21 according to a select signal, so as to select one of the portable devices 25 to transmit data with the host computer 21 via the differential data pins 2113, 2115. Wherein, the select signal is generated according to the on/off states of all the portable devices 25.
Finally,
In step S605, the host computer 21 determines whether there is only one of the portable devices 25 turned on. If not, it indicates that the at least two switch circuits of the portable devices 25 are closed to enable to occupy the differential data lines (pins 2113, 2115). Therefore, in step S607, unnecessary portable devices 25 must be turned off until there is only one portable device 25 staying the on-line state. That is, the data transmission paths between the host computer 21 and the unnecessary portable devices 21 are disconnected when not only one data transmission path between the host computer 21 and the portable devices 25 is connected. In one embodiment, the host computer 21 displays a warning window to notify users to turn off the unnecessary portable devices 25.
If determining that there is only one of the portable devices 25 turned on, the switch circuit of the turned-on portable device 25 is closed. Therefore, the portable device 25 obtains electricity provided by the host computer 21 via the voltage pin 2111 in step S609, and further transmits data with the host computer 21 via the differential data pins 2113, 2115 in step S611. When finishing the operation of the portable device 25, user can turn it off and turn on (or plug in) another portable device 25, and flow returns to step S603 to perform similarly control.
According to the above embodiment, the data transmitting system and method for portable devices, provided in the present invention, switches the switch circuit to communicate with the host computer by turning on the portable device. In this scheme, it can simply substitute for the USB hub by controlling to turn on only one portable device at a time. Accordingly, the present invention not only decreases system cost but also saves power consumption.
Although specific embodiments have been illustrated and described, it will be appreciated by those skilled in the art that various modifications may be made without departing from the scope of the present invention, which is intended to be limited solely by the appended claims.