Wireless human interface device packet compression system and method for reducing power consumption

Abstract

A method, system, and computer-readable storage medium are provided for compressing a packet of data sent across a wireless transmission path to reduce power consumption in a wireless input device. The wireless input device preferably includes a human interface device that sends a report that is of variable length and compressed by refraining from transmitting unused bytes of a packet containing the report. Certain byte fields can be swapped, such as a first scan code byte field with a modifier key byte. Also, any reserved bytes that are not used can be removed in order to convert a standard HID report format into the present compressed report format. By removing unused bytes and optimally swapping the more prevalently used byte into the first field while removing any reserved bytes, the compressed report reduces the amount of power consumed to transmit the compressed report, relative to a non-compressed and fixed-length report of conventional HID input devices. A report descriptor maintains the compresses format and provides that format, along with the compressed report, to the USB interface, for example, to recompile the standard report at the input port of, for example, a personal computer. The input device can be, for example, a keyboard and a pointing device. If a pointing device is used, the scroll wheel and button information can be combined into a single byte rather than utilizing two bytes as in conventional HID reports.