Enabling Efficient Communication Between a Host and Multiple USB Devices
The present invention relates generally to devices and methods for communicating between a host computer and a peripheral device, such as a monitor or printer, and, more particularly, to enable efficient communication between a host and a plurality of such USB peripheral devices without substantial bandwidth degradation. In one embodiment, a device driver, in data communication with a configuration application executing on a host computer, instructs a secondary USB device to accept data packets related to not only its own unique address but also of at least one other primary USB device whose address was additionally caused to be stored with the USB device.
1 . A method of concurrently transmitting data from a host to multiple USB devices, comprising the steps of:
a. Selecting a primary USB device and a plurality of secondary USB devices;
b. Communicating an address of said primary USB device to a device driver for each of said plurality of secondary USB devices; and
c. Having said device drivers instruct each of said plurality of secondary USB devices to monitor and utilize data sent to said address of the primary USB device.
2 . The method of claim 1 wherein the host resends data in response to an error experienced by said primary USB device.
3 . The method of claim 1 wherein said multiple USB devices are monitors.
4 . The method of claim 1 wherein said device drivers instruct each of said plurality of secondary USB devices to monitor and utilize data sent to said address of the primary USB device by using a vendor specific request.
5 . The method of claim 1 wherein each of said secondary USB devices store the address of the primary USB device in a hardware register.
6 . The method of claim 4 wherein, when a data packet is received by each secondary USB device, the secondary USB device compares the data packet's address field with both an address assigned to said secondary USB device and the address of the primary USB device.
7 . The method of claim 5 wherein said secondary USB device keeps the data packet if the data packet's address field matches either the address assigned to said secondary USB device or the address of the primary USB device.
8 . The method of claim 5 wherein said secondary USB device discards the data packet if the data packet's address field does not matches either the address assigned to said secondary USB device or the address of the primary USB device.
9 . The method of claim 1 wherein, for at least some of the data packets sent by the host, the primary USB device responds with an acknowledgement to indicate to the host that the packet has been properly received by the primary USB device.
10 . The method of claim 8 wherein, for all of the data packets sent by the host, the secondary USB device does not respond with an acknowledgement to indicate to the host that the packet has been properly received by the secondary USB device.
11 . A method of broadcasting data from a host to at least two USB devices, comprising the steps of:
a. Selecting a primary USB device and at least one secondary USB device;
b. Communicating an address of said primary USB device to a device driver for said at least one secondary USB device;
c. Having said device drivers instruct each of said plurality of secondary USB devices to monitor and utilize data sent to said address of the primary USB device by using a vendor specific request; and
d. Transmitting data to the address of the primary USB device only and not transmitting the same data to the address of the secondary USB device.
12 . The method of claim 10 wherein said multiple USB devices are monitors.
13 . The method of claim 10 wherein said host resends data in response to an error experienced by said primary USB device.
14 . The method of claim 10 wherein said host does not resend data in response to an error experienced by said at least one secondary USB device.
15 . The method of claim 10 wherein each of said secondary USB devices store the address of the primary USB device in a hardware register.
16 . The method of claim 14 wherein, when a data packet is received by the at least one secondary USB device, the secondary USB device compares the data packet's address field with both an address assigned to said secondary USB device and the address of the primary USB device.
17 . The method of claim 15 wherein said secondary USB device keeps the data packet if the data packet's address field matches either the address assigned to said secondary USB device or the address of the primary USB device.
18 . The method of claim 15 wherein said secondary USB device discards the data packet if the data packet's address field does not matches either the address assigned to said secondary USB device or the address of the primary USB device.
19 . The method of claim 10 wherein, for at least some of the data packets sent by the host, the primary USB device responds with an acknowledgement to indicate to the host that the packet has been properly received by the primary USB device.
20 . The method of claim 18 wherein, for all of the data packets sent by the host, the secondary USB device does not respond with an acknowledgement to indicate to the host that the packet has been properly received by the secondary USB device.