Method and apparatus for detecting the type of interface to which a peripheral device is connected

• US 6,795,949 B2
• Filed: 09/30/2002
• Issued: 09/21/2004
• Est. Priority Date: 07/08/1998
• Status: Expired due to Term

• Current Assignee: Microsoft Technology Licensing LLC (Microsoft Corporation)
• Original Assignee: Microsoft Corporation
• Inventors: Hanson, Mark T., Sherman, Nathan C., Featherston, Lord Nigel, Holo, David L., Drake, Victor P., Mullins, Keith
• Primary Examiner(s): Siek, Vuthe
• Assistant Examiner(s): Levin, Naum
• Application Number:
  US10/260,188
• Publication Number:
  US 20030074176A1
• Time in Patent Office: 722 Days
• Field of Search: 716/1, 716/4-6, 716/12, 716/8, 710/129, 710/100, 710/15, 710/63, 710/62, 710/110, 710/8-14, 710/305-317, 326/30, 360/69, 708/854, 713/400
• US Class Current: 716/106
• CPC Class Codes: G06F 13/4068 Electrical coupling
• CPC Class Codes: G06F 13/4086 Bus impedance matching, e.g. termination

Abstract

A peripheral device is connectable to a computer having one of a first interface and a second interface. The first interface communicates with the peripheral device over a differential data connection having a first data conductor and a second data conductor. The second interface communicates with the peripheral device over a clock conductor and a single ended data connection which includes a data conductor. The peripheral device has first and second communication conductors configured for connection to the first and second data conductors in the differential data connection when the computer includes the first interface and is configured for connection to the first data conductor in the single ended data connection and the clock conductor when the computer is provided with the second interface. The peripheral device includes an interface detection component coupled to the first and second communication conductors and configured to detect which of the first and second interfaces the peripheral device is connected to. The peripheral device also includes a controller component configured to communicate between the peripheral device according to a protocol corresponding to the detected interface.

Claims

1. A peripheral device connectable to a computer, the computer having one of a first interface and a second interface, the first interface communicating with the peripheral device over a differential data connection including a first data conductor and a second data conductor, and the second interface communicating with the peripheral device over a single ended data connection, including at least a first data conductor, and a clock conductor, the peripheral device comprising:

first and second conductors configured for connection to the first and second data conductors when the computer includes the first interface, and configured for connection to the first data conductor and the clock conductor when the computer includes the second interface;

an interface detector, operably coupled to at least one of the first and second conductors, configured to detect which of the first and second interfaces the peripheral device is connected to, based on sensed signal levels on at least one of the first and second conductors, and to provide a connection output indicative of the detected interface; and

a controller component, operably coupled to the interface detection component, configured to communicate with the computer over the first and second conductors according to a protocol corresponding to the detected interface.

2. A computer readable medium for use in a peripheral device connectable to a computer, the computer having one of a first peripheral device interface and a second peripheral device interface, the first peripheral device interface having a differential data connection including a first data conductor and a second data conductor, and the second peripheral device interface having a single ended data connection, including a first data conductor, and a clock conductor, the peripheral device including first and second conductors configured for connection to the first and second data conductors when the computer includes the first peripheral device interface, and configured for connection to the first data conductor and the clock conductor when the computer includes the second peripheral device interface, the computer readable medium including instructions stored thereon which when executed by the peripheral device, cause the peripheral device to execute the steps of:

detecting which of the first and second peripheral device interfaces the peripheral device is connected to by signal activity on at least one of the first and second conductors; and

communicating with the computer over the first and second conductors according to a protocol corresponding to the detected interface.

3. A method implemented by a peripheral device for detecting whether the peripheral device is connected to a first interface or a second interface in a computer, the first interface communicating with the peripheral device over a differential data connection including a first data conductor and a second data conductor, and the second interface communicating with the peripheral device over a single ended data connection, including a first data conductor, and a clock conductor, the peripheral device including first and second conductors configured for connection to the first and second data conductors when the computer includes the first interface, and configured for connection to the first data conductor and the clock conductor when the computer includes the second interface, the method comprising:

detecting which of the first and second interfaces the peripheral device is connected to by attempting to impose a signal level on at least one of the first and second conductors and detecting a signal level on the at least one conductor; and

communicating with the computer according to a protocol corresponding to the detected interface.