Method and device for deriving pen position and reporting pen position to host computer

A touch controller configured to be coupled to a touch surface on which a pen indicates a position and to be coupled to a host computer, the touch controller comprising:

• a memory including a buffer area for retaining a plurality of reports;
• and
• processing circuitry coupled to the memory and configured to:
• derive a pen position on the touch surface based on signals received by the touch controller from the touch surface and/or from the pen at each determined scanning time;
• for each derived position, generate a report including a first area including position data indicating the derived pen position and a second area including at least a pen pressure value, to thereby generate and store the plurality of reports in the buffer area;
• and
• sequentially transmit the plurality of reports to the host computer and, in response to detecting a pen-up event indicating that the pen is separated from the touch surface, modify one or more of the pen pressure values included in one or more of the plurality of reports that have not been transmitted, and transmit the one or more of the plurality of reports including the modified one or more of the pen pressure values to the host computer.

A method performed by a device, which is coupled to a touch surface on which a pen indicates a position, and which is coupled to a host computer, the method comprising:

• deriving a pen position on the touch surface based on signals received by the device from the touch surface and/or from the pen at each determined scanning time;
• for each derived pen position, generating a report including a first area including position data indicating the derived pen position and a second area including a pen pressure value indicating a pressure applied to a pen tip of the pen, to thereby generate a plurality of reports;
• and
• sequentially transmitting the plurality of reports to the host computer and, in response to detecting a pen-up event indicating that the pen is separated from the touch surface, rewriting one or more of the pen pressure values included in one or more of the plurality of reports that have not been transmitted, and transmitting the one or more of the plurality of reports including the rewritten one or more of the pen pressure values to the host computer.

A touch controller configured to be coupled to a touch surface on which a pen indicates a position and to be coupled to a host computer, the touch controller comprising:

• a memory including a buffer area for retaining a plurality of reports;
• and
• processing circuitry coupled to the memory and configured to:
• derive a pen position on the touch surface based on signals received by the touch controller from the touch surface and/or from the pen at each determined scanning time;
• for each derived position, generate a report including a first area including position data indicating the derived pen position and a second area including a pen pressure value indicating a pressure applied to a pen tip of the pen, to thereby generate the plurality of reports;
• and
• sequentially transmit the plurality of reports to the host computer and, in response to detecting a pen-up event indicating that the pen is separated from the touch surface, rewrite one or more of the pen pressure values included in one or more of the plurality of reports that have not been transmitted, and transmit the one or more of the plurality of reports including the rewritten one or more of the pen pressure values to the host computer.