CN104932615A - Universal serial bus expansion seat and method for charging portable device by using same - Google Patents

Abstract

Universal Serial Bus docking station and method of charging portable devices. The invention provides a Universal Serial Bus (USB) docking station, which includes: a plurality of downstream ports; an upstream port for connecting the USB docking station to a portable device, wherein the upstream port includes an OTG ID pin and a differential pair; and a microcontroller for detecting multiple operating states of the portable device. When the microcontroller detects that the portable device is in a USB OTG master mode and has entered a suspend state, the microcontroller controls the portable device to be controlled by the USB OTG by switching the state of the OTG ID pin. The master mode is switched to a USB device mode to charge the portable device through the upstream port.

Description

Universal serial bus docking station and method for charging portable devices

technical field

The present invention relates to a dock for a portable device, in particular to a universal serial bus (USB) dock that can charge the portable device according to the detected operating status of the portable device.

Background technique

In recent years, there have been several developments in the need for new functionality in computer systems and the ability to easily connect peripheral devices to computer systems. One of them is developed as Universal Serial Bus (Universal Serial Bus). The development of the USB specification is to provide external expansion, which can make adding peripheral devices as simple as hooking up a handset on a telephone. Since the invention of the USB specification, it has been widely accepted by the market.

The USB On-the-Go (OTG) specification defines two roles of devices, such as OTG A device and OTG B device. This term defines which side provides power to the link and which is initially the host. The OTG A device is a power provider, and the OTG B device is a power user. The default connection configuration is that the OTG A device acts as a USB host, and the OTG B device acts as a USB peripheral device. The USB OTG specification opens up a device that can play the roles of master and slave, so it subtly changes the above terminology. With OTG, a USB device can be a master when acting as the master of the connection, or a peripheral when acting as the slave of the connection. The choice of whether to be a host or a peripheral is entirely determined by which end of the cable the USB device is plugged into. When a USB device is connected to the A end of the cable, the USB device is the A device and acts as the default host. When a USB device is connected to the B end of the cable, the USB device is the B device and acts as the default peripheral device.

In the USB battery charging specification, the USB device always draws power from the USB host. If a user wants to use his portable device as a USB host, he needs to use a special type of cable with an ID pin. Therefore, USB micro A/B cables with OTG ID pins are often used. When a USB device is connected to a portable device using a USB micro A/B cable, the portable device will switch from the USB device mode to the USB OTG master mode, and the portable device will provide power to the connected USB device.

In a scenario using a docking station, the user may be stationary for a long period of time and needs to use large and traditional input devices such as a keyboard and mouse. When the portable device is in USB OTG master mode, the USB docking station can provide the required video and USB input/storage functions. However, when the portable device is in USB OTG master mode, the portable device uses its own power source. Although the USB docking station has its own power source, the power supply of the USB docking station cannot be shared with the portable device because this function is not defined in the USB battery charging specification.

Contents of the invention

The present invention provides a universal serial bus (USB) docking station, comprising: a plurality of downstream ports; an upstream port for connecting the USB docking station to a portable device, wherein the upstream port includes an OTG ID pin and a differential pair; and a microcontroller for detecting a plurality of operating states of the portable device. When the microcontroller detects that the portable device is in a USB OTG master mode and has entered a suspend (suspend) state, the microcontroller controls the portable device by switching the state of the OTG ID pin from the USB OTG The host control mode is switched to a USB device mode, so as to charge the portable device through the upstream port.

The present invention also provides a method for charging a portable device using a Universal Serial Bus (USB) docking station, wherein the USB docking station includes a plurality of downstream ports and an upstream port, and the method includes: through the upstream port Connecting the USB docking station to the portable device, wherein the upstream port includes an OTG ID pin and a differential pair; detecting multiple operating states of the portable device; and when detecting that the portable device is in a USB OTG master mode and has entered a suspend (suspend) state, by switching the state of the OTG ID pin to control the portable device to switch from the USBOTG master mode to a USB device mode, so as to charge the portable device through the upstream port .

Description of drawings

FIG. 1 is a block diagram showing a USB docking station according to an embodiment of the present invention.

【Symbol Description】

100～USB expansion seat;

110～microcontroller;

120～downlink port;

130～uplink port;

140～button;

150～portable device;

D+, D-, VBUS, OTG ID, GND ~ pins.

Detailed ways

In order to make the above-mentioned objects, features and advantages of the present invention more comprehensible, a preferred embodiment will be described in detail below together with the accompanying drawings.

FIG. 1 is a block diagram showing a USB docking station according to an embodiment of the present invention. In one embodiment, the USB docking station 100 includes a microcontroller 110 , a plurality of downstream ports 120 , and an upstream port 130 . The uplink port 130 can couple the USB docking station 100 to a portable device 150 such as a mobile phone or a tablet computer. The downstream port 120 can couple the USB docking station 100 to other USB devices, such as a monitor, keyboard, or mouse, which can help input or output information to the portable device connected to the USB docking station 100 . In one embodiment, the upstream port 130 is a USB micro A/B connector, which includes a differential pair (D+ and D- pins), a VBUS power pin, a ground (GND) pin, and One OTG ID pin. The microcontroller 110 can detect the operating state of the portable device 150 according to the state of the OTG ID pin. For example, when the OTG ID pin is in a first state (for example: grounded), the microcontroller 110 can know that the portable device 150 is in a working state. In another embodiment, the upstream port 130 is compatible with the USB micro A/B interface, which includes a differential pair (D+ and D- pins), a VBUS power pin, a ground (GND) pin, and One OTG ID pin. Further, there are many types of USB connectors on the market, but all of them are equipped with the main USB pins mentioned above.

In the situation when a user connects the portable device 150 to the USB docking station 100, the USB docking station 100 can enable (enable) the USB OTG host mode of the portable device 150, so as to enable connection to the USB docking station The use of the USB peripheral of the downstream port 120 of the cradle 100, and normal data transmission between the portable device 150 and the USB peripheral. It should be noted that the portable device 150 cannot use the upstream port 130 for charging in the USB OTG master mode, because the portable device 150 acts as a "host" in the USB OTG master mode.

When the portable device 150 utilizes the differential pair to send a suspend (suspend) command to the USB docking station 100, the microcontroller 110 of the USB docking station 100 can set the state of the OTG ID pin to a second state (for example: Floating (floating)), so that the portable device 150 enters a USB (device) device mode from the USB OTG master control mode, and also makes the USB docking station 100 use the uplink port 130 to charge the portable device 150. It should be noted that when the portable device 150 has been idle for a predetermined time, the portable device 150 will automatically enter a suspend state. Optionally, when the user manually turns off the power of the screen of the portable device 150, the portable device 150 may also enter the suspend state, but the invention is not limited thereto. When entering the suspend state, the portable device 150 can send a suspend command to the USB docking station 100 .

Furthermore, when the USB docking station receives a suspend command from the portable device 150, the USB docking station 100 disconnects (disconnect) the differential pair, and then short-circuits (short) the differential pair, so that the portable device 150 detects Uplink port 130 has been physically disconnected and replugged into portable device 150 . Then, the USB docking station 100 can set the state of the OTG ID pin to a second state to force the portable device 150 to enter the USB device (device) mode from the USB OTG master control mode. It should be noted that the USB docking station 100 can set the voltage of the differential pair when the portable device 150 is in the USB device mode, so as to provide multiple fast charging modes to charge the portable device 150 . For example, the fast charging mode can be a power delivery mode defined in the USB battery charging standard v1.2, an Apple mode, or another fast charging mode, but the present invention is not limited thereto .

In one embodiment, the USB docking station 100 further includes a button 140 , which is a physical button for switching the USB operation mode of the portable device 150 through the GPIO interface. For example, when the user needs to switch the portable device 100 from the USB device mode back to the USB OTG master mode, the user can press the button 140 . Then, the microcontroller 110 detects that the button 140 is pressed, and uses the setting GPIO interface to set the state of the OTG ID pin to the first state (for example: grounding), thereby notifying the portable device 150 to enter the USB from the USB device mode. OTG master mode.

In another embodiment, when the user needs to switch the portable device from the USB device mode back to the USB OTG master control mode, the user can use one of the peripheral devices connected to the USB docking station 100 to send a trigger signal, so that the USB The docking station 100 can disconnect the differential pair to leave the USB device mode. Then, the USB docking station 100 can activate the differential pair and set the state of the OTG ID pin to the first state to notify the portable device 150 to enter the USB OTG master mode.

In yet another embodiment, instead of waiting for the portable device 150 to enter the suspend state, the USB docking station 100 sends a specific suspend command through a virtual endpoint (virtual endpoint) defined in advance by the USB docking station 100, so that the USB docking station 100 can actively Ground forces the portable device 150 to enter the suspend state from the working state. The specific pause command may be triggered by the user pressing another button (not shown in FIG. 1 ). In one embodiment, the virtual endpoint belongs to a virtual connection device coupled to a virtual port of the USB docking station 100 . For example, the virtual endpoint is used to emulate a keyboard, and it can send a suspend command to the portable device 150 . That is, the virtual endpoint is a predefined endpoint in the USB docking station 100 for suspending the portable device 150 . In the manner described above, there is no need to wait for the portable device 150 to automatically suspend. In other words, when the user needs to charge the portable device at any time, the above method provides more flexibility to the user.

In another embodiment, the specific pause command can be triggered by the button 140 mentioned earlier. In this case, the button 140 may have various functions depending on the state of the portable device 150 . When the portable device 150 is in the USB OTG master mode, when the button 140 is pressed, the portable device 150 enters the suspend state. When the portable device 150 is in the USB device mode, when the button 140 is pressed, the portable device 150 will be switched from the USB device mode to the USB OTG master mode.

To sum up, when the USB OTG master control mode is turned on, the USB docking station 100 can detect the working state of the portable device 150 . The USB docking station 100 can also control the portable device 150 to switch from the USB OTG master control mode to the USB device mode by switching the state of the OTG ID pin. In addition, the USB docking station 100 can further charge the portable device 150 through the uplink port 130 . The above features of the USB docking station 100 are non-obvious because the features are not defined in the USB standard. The present invention utilizes hardware and firmware functions to enable the above features, which allow the portable device 150 to perform fast charging when the user does not need to use the USB peripheral and the portable device 150 is still connected to the USB docking station.

The method of the present invention, or a specific form or part thereof, may be included in a physical medium in the form of program code, such as a floppy disk, an optical disk, a hard disk, or any other machine-readable (such as computer-readable) storage medium, wherein, When the program code is loaded and executed by a machine, such as a computer, the machine becomes a device or system for participating in the present invention. The method, system and device of the present invention can also be transmitted in the form of program code through some transmission media, such as wires or cables, optical fibers, or any transmission type, wherein when the program code is received, loaded and executed by a machine such as a computer , the machine becomes a device or system for participating in the present invention. When implemented on a general-purpose processor, the program code combines with the processor to provide a unique device that operates similarly to application-specific logic circuits.

Although the present invention is disclosed as above with the embodiment, it is not intended to limit the scope of the present invention, those skilled in the art can make some changes and modifications without departing from the spirit and scope of the present invention, so the protection scope of the present invention The scope defined by the appended claims shall prevail.

Claims (18)

1. A universal serial bus USB docking station, comprising: Multiple downstream ports; an upstream port for connecting the USB docking station to a portable device, wherein the upstream port includes an OTG ID pin and a differential pair; and a microcontroller for detecting a plurality of operating states of the portable device, Wherein when the microcontroller detects that the portable device is in the USB OTG master mode and has entered a suspended state, the microcontroller controls the portable device to switch from the USB OTG master mode by switching the state of the OTG ID pin to USB device mode, whereby the portable device is charged through the upstream port. 2. The USB docking station as claimed in claim 1, wherein the upstream port is implemented by a USB micro A/B interface. 3. The USB docking station as claimed in claim 1, wherein the upstream port is compatible with the USB microA/B interface. 4. The USB docking station as claimed in claim 1, further comprising: a first button for switching the portable device from the USB device mode to the USB OTG master mode. 5. The USB docking station as claimed in claim 1, further comprising: a second button for controlling the portable device to enter the suspend state when the portable device is in the USB OTG master control mode. 6. The USB docking station as claimed in claim 1, wherein when the portable device is in the USBOTG master mode, the microcontroller performs a plurality of operations of the portable device and the plurality of downstream ports connected to the USB docking station. Data transfer between USB peripheral devices. 7. The USB docking station as claimed in claim 1, wherein when the portable device has entered the suspend state, the portable device sends a suspend command to the microcontroller, and when the microcontroller receives the suspend command, The microcontroller interrupts the differential pair and then restarts the differential pair so that the portable device enters the USB device mode from the USB OTG master mode. 8. The USB docking station as claimed in claim 1, wherein when the portable device enters the USB device mode, the microcontroller also short-circuits the differential pair to activate the fast charging mode. 9. The USB docking station as claimed in claim 6, wherein when the user uses one of the plurality of USB peripheral devices to send a trigger signal, the USB docking station controls the portable device to enter from the USB device mode according to the trigger signal The USB OTG master mode. 10. A method for charging a portable device utilizing a Universal Serial Bus USB docking station, wherein the USB docking station includes a plurality of downstream ports and upstream ports, the method comprising: Connect the USB docking station to the portable device through the upstream port, wherein the upstream port includes an OTG ID pin and a differential pair; detecting a plurality of operating states of the portable device; and When it is detected that the portable device is in the USB OTG master mode and has entered the suspend state, the portable device is controlled to switch from the USB OTG master mode to the USB device mode by switching the state of the OTG ID pin, so that the upstream The port charges the portable device. 11. The method according to claim 10, wherein the upstream port is implemented by a USB micro A/B interface. 12. The method of claim 10, wherein the upstream port is compatible with a USB micro A/B interface. 13. The method of claim 10, wherein the USB docking station further comprises: a first button, and the method further comprises: By pressing the first button, the portable device is switched from the USB device mode to the USB OTG master mode. 14. The method as claimed in claim 10, wherein the USB docking station further comprises: a second button, and the method further comprises: By pressing the second button to control the portable device to enter the suspend state when the portable device is in the USB OTG master mode. 15. The method of claim 10, further comprising: When the portable device is in the USB OTG master mode, data transmission between the portable device and a plurality of USB peripheral devices connected to the plurality of downstream ports of the USB docking station is performed. 16. The method of claim 10, further comprising: sending a suspend command to the portable device when the portable device has entered the suspend state; When the portable device receives the suspend command, it interrupts the differential pair and then restarts the differential pair, so that the portable device enters the USB device mode from the USB OTG master mode. 17. The method of claim 10, further comprising: When the portable device enters the USB device mode, the differential pair is shorted to activate a fast charging mode. 18. The method of claim 15, further comprising: When the user utilizes one of the USB peripheral devices to send a trigger signal, the USB docking station is controlled according to the trigger signal to control the portable device to enter the USB OTG master mode from the USB device mode.