摘要 |
Reporting an attribute of a device via PS/2 protocols to a host executing an industry standard PS/2 port driver that does not include explicitly recognize the attribute. For example, a wireless mouse reports a battery state and a signal quality state through a standard PS/2 port driver that does not recognize any command or identifier for battery state or signal quality state. The attribute state is encoded in a standard PS/2 data packet. The standard PS/2 data packet is uniquely identified as an attribute packet by encoding data corresponding to highly unlikely mouse movement. A filter driver running on the host activates transmission of the attribute packets by commanding the port driver to issue a unique sequence of standard PS/2 commands, which the mouse system recognizes. The filter driver intercepts incoming PS/2 data packets, recognizes the unlikely data values that identify an attribute packet, and decodes the attribute state. |