Abstract: In one embodiment, a stylus includes one or more electrodes and one or more computer-readable non-transitory storage media embodying first logic for transmitting signals wirelessly to a device through a touch-sensor of the device. The stylus has a first power mode in which components of the stylus for receiving signals from or transmitting signals to the device are powered off; a second power mode in which components of the stylus for receiving signals from the device are powered on at least periodically and components of the stylus for transmitting signals to the device are powered off; and a third power mode in which components of the stylus for transmitting signals to the device are powered on at least periodically. The media further embodies second logic for transitioning the stylus from one of the first, second, and third power modes to another one of the first, second, and third power modes.

Abstract: In one embodiment, computer-readable non-transitory storage media receive one or more signals based on motion of an object, a device, or both. The received signals are compared to a motion profile which defines unintended motion of the object, the device, or both, and this comparison determines whether any of the signals represent unintended motion of the stylus or device. The received signals are then processed to correct for the unintended motion defined by the motion profile.

Abstract: In one embodiment, computer-readable non-transitory storage media receive one or more signals based on motion of an object, a device, or both. The received signals are compared to a motion profile which defines unintended motion of the object, the device, or both, and this comparison determines whether any of the signals represent unintended motion of the stylus or device. The received signals are then processed to correct for the unintended motion defined by the motion profile.

Abstract: In one embodiment, a stylus includes one or more electrodes and one or more computer-readable non-transitory storage media embodying first logic for transmitting signals wirelessly to a device through a touch-sensor of the device. The stylus has a first power mode in which components of the stylus for receiving signals from or transmitting signals to the device are powered off; a second power mode in which components of the stylus for receiving signals from the device are powered on at least periodically and components of the stylus for transmitting signals to the device are powered off; and a third power mode in which components of the stylus for transmitting signals to the device are powered on at least periodically. The media further embodies second logic for transitioning the stylus from one of the first, second, and third power modes to another one of the first, second, and third power modes.

Abstract: In one embodiment, an active stylus includes a transmitter configured to transmit electrical signals to a device through a touch sensor of the device. The active stylus also includes a receiver configured to receive electrical signals from the device through the touch sensor of the device. Furthermore, the active stylus includes a controller configured to determine a strength of an electrical signal received by the receiver from the touch sensor of the device and instruct the transmitter to transmit electrical signals to the device at a voltage based at least on the determined strength of the electrical signal received by the receiver.

Abstract: In one embodiment, a stylus includes one or more electrodes and one or more computer-readable non-transitory storage media embodying first logic for transmitting signals wirelessly to a device through a touch-sensor of the device. The stylus has a first power mode in which components of the stylus for receiving signals from or transmitting signals to the device are powered off; a second power mode in which components of the stylus for receiving signals from the device are powered on at least periodically and components of the stylus for transmitting signals to the device are powered off; and a third power mode in which components of the stylus for transmitting signals to the device are powered on at least periodically. The media further embodies second logic for transitioning the stylus from one of the first, second, and third power modes to another one of the first, second, and third power modes.

Abstract: In one embodiment, an active stylus includes a transmitter configured to transmit electrical signals to a device through a touch sensor of the device. The active stylus also includes a receiver configured to receive electrical signals from the device through the touch sensor of the device. Furthermore, the active stylus includes a controller configured to determine a strength of an electrical signal received by the receiver from the touch sensor of the device and instruct the transmitter to transmit electrical signals to the device at a voltage based at least on the determined strength of the electrical signal received by the receiver.

Abstract: In one embodiment, a method for determining the location of a touch on a touch sensor includes receiving input signals in response to a touch proximate to a location on the touch sensor. Each input signal may have a total capacitance that includes a first capacitance associated with the touch and a second capacitance that is parasitic capacitance. The parasitic capacitance of one or more of the input signals may be adjusted to result in the second capacitance of each of the input signals being substantially equal. An average capacitance of the adjusted input signals may be calculated. The location of the touch on the touch sensor may then be determined based on a comparison of the total capacitance of each of the input signals and the average capacitance of the input signals.

Abstract: A method of one embodiment includes generating, by a stylus, a composite signal. The composite signal includes a first signal having a first frequency, the first signal being used by a touch-sensing device to determine a position of the stylus relative to the touch-sensing device, and a second signal having a second frequency. The second signal may include status information such as an amount of force exerted on the stylus, battery information, orientation information, information indicating whether the stylus is within a threshold distance of the touch-sensing device, information indicating a status of a button of the stylus, and/or information indicating input from a user of the stylus. Furthermore, the second frequency is higher than the first frequency. The stylus sends the composite signal to the touch-sensing device, and an electrode array of the touch-sensing device may receive the composite signal.

Abstract: A digital microprocessor device (2) has: a central processing unit; a memory (8); and an output signal module (4). The output signal module comprises: a counter (6) arranged to count to a predetermined count value; and at least one comparator (10a, 10b, 10c) arranged to change an output signal (14a, 14b, 14c) from a first output state to a second output state when the counter reaches a predetermined comparator value. The output signal module is arranged to load automatically from the memory at least one parameter selected from the group comprising: the predetermined count value, the predetermined comparator value and the first output state or the second output state, without receipt of an instruction from the central processing unit.

Abstract: In one embodiment, a method comprises generating, by a controller, a plurality of drive signals. The method further includes simultaneously transmitting, by the controller, the plurality of drive signals to a plurality of drive electrodes disposed on a touch sensor. The method further includes sensing a sense electrode of a plurality of sense electrodes disposed on the touch sensor. The sensing comprises measuring, for each drive electrode of the plurality of drive electrodes, at least one value indicative of a capacitance between the sense electrode and the drive electrode.

Abstract: In one embodiment, a stylus includes electrodes operable to transmit signals wirelessly to a device through a touch sensor of the device. The stylus also includes one or more computer-readable non-transitory storage media within the stylus and embodying logic that is operable when executed to access first data representing a gesture made with the stylus by a user, such as a sequence of manipulations of the stylus. The logic is further operable to access second data representing a pre-defined authentication sequence and compare the first data with the second data. This comparison may authenticate the user to the stylus or the device, authenticate the stylus to the device or the user, or authenticate the device to the stylus or the user.

Abstract: A method of one embodiment includes generating, by a touch-sensing device, a first signal comprising information identifying a first electrode line of an electrode array of the touch-sensing device, the first signal having a first strength. The first electrode sends the first signal to a stylus, which receives the first signal, the first signal having a received strength. The stylus sends a second signal comprising information based on the received first signal, and the touch-sensing device receives the second signal. A position of the stylus is determined based at least in part on the information identifying the first electrode line and the received strength of the first signal.

Abstract: In one embodiment, a stylus operable to communicate wirelessly with a device through a touch sensor of the device contains one or more computer-readable non-transitory storage media embodying logic that is operable when executed to access first data representing a recently occurred authentication event involving the stylus or the device. The logic is further operable to access second data representing a pre-defined authentication event. The logic is further operable to compare the first data with the second data to authenticate a user to the stylus or the device, a stylus to the user or the device, or a device to the user or the stylus.

Abstract: In one embodiment, a system comprises a stylus and a touch sensor. The stylus is operable to transmit a first signal. The touch sensor comprises a first plurality of electrode lines and a controller. Each electrode line is operable to sense the first signal transmitted by a stylus. The stylus tip of the stylus is located at a position relative to the first plurality of electrode lines at the time of transmission of the first signal. The controller is operable to measure a voltage, charge, or capacitance of the sensed first signal on each electrode line of the first plurality of electrode lines and estimate the position of the stylus tip based on interpolation of the measured voltages on each electrode line of the first plurality of electrode lines.

Abstract: In one embodiment, a stylus has one or more sensors that detect the movement of the stylus, such as an accelerometer, a gyroscope, or a magnetometer. The stylus wirelessly transmits signals to a device based on the movement of the stylus.

Abstract: In one embodiment, a stylus includes one or more electrodes and one or more computer-readable non-transitory storage media embodying logic for transmitting signals wirelessly to a device through a touch sensor of the device. The computer-readable non-transitory storage media of the stylus further embodies logic for allocating between the stylus and the device electric energy available at the stylus or the device based on one or more first criteria.

Abstract: A system of one embodiment includes a touch-sensing device and a stylus. The touch sensing device includes an electrode array, which includes a plurality of electrode line pairs, and a controller. Each electrode line pair includes a first and second electrode line to send a first and second signal, respectively. The stylus includes a sensor to measure the first and second signals, a signal processor to determine position information, and a transmitter to send position information to the touch-sensing device. A method of another embodiment includes sending, by a first electrode line, a first signal having a first frequency. A second electrode line sends a second signal having a second frequency. A stylus receives the first and second signals. The stylus sends a response signal to the touch-sensing device based on the first and second signals. A position of the stylus is determined based on the first and second signals.

Abstract: In one embodiment, an active stylus includes a transmitter configured to transmit electrical signals to a device through a touch sensor of the device. The active stylus also includes a receiver configured to receive electrical signals from the device through the touch sensor of the device. Furthermore, the active stylus includes a controller configured to determine a strength of an electrical signal received by the receiver from the touch sensor of the device and instruct the transmitter to transmit electrical signals to the device at a voltage based at least on the determined strength of the electrical signal received by the receiver.

Abstract: In one embodiment, a method includes receiving a signal at a stylus. The stylus is operable to wirelessly transmit signals to and receive signals from a device. The stylus includes a plurality of electrodes disposed in a tip of the stylus. The method includes determining a characteristic of the signal, and based at least in part on the characteristics of the signal, a threshold for determining whether to process signals received wirelessly from the device is dynamically adjusted.