Abstract: In one embodiment, a method includes receiving at a stylus a receive signal from a device. The stylus includes one or more computer-readable media embodying logic, and the device includes a touch sensor. The receive signal is received at the stylus through the touch sensor of the device and one or more electrodes of the stylus. The method includes filtering the receive signal for processing by the logic and processing, by the logic, the receive signal as filtered.

Abstract: In one embodiment, an apparatus comprises a data-transmitting component and a data-receiving component. The data-transmitting component is operable to: select a set of first reference values and a set of second reference values respectively indicating a lower bound and an upper bound of a range of values; respectively represent the set of first reference values and the set of second reference values as a set of first pulses and a set of second pulses; represent a set of analog values as a set of third pulses, each third pulse having a third amplitude between the first amplitude of a corresponding first pulse and the second amplitude of a corresponding second pulse that is determined based on a percentage of the corresponding analog value within the range of values; and transmit the set of first pulses, the set of third pulses, and the set of second pulses to the data-receiving component.

Abstract: In one embodiment, a method includes accessing, by a stylus, data associated with a particular user of the stylus, the data associated with the particular user being stored in a memory of the stylus; and by the stylus, wirelessly transmitting the data to a device in response to the stylus contacting a touch sensor of the device.

Abstract: In one embodiment, a device includes a form factor of a stylus. The form factor includes a surface area. The device also includes one or more substrates disposed along one or more portions of the surface area; and one or more touch sensors disposed on one or more of the substrates. At least one of the touch sensors includes a distinct touch-sensitive area that includes a touch-sensitive button, a touch-sensitive wheel, or a touch-sensitive slider. The device also includes a computer-readable non-transitory storage medium coupled to one or more of the touch sensors and embodying logic configured to associate the distinct touch-sensitive area with a pre-determined function of the device.

Abstract: In one embodiment, a method includes modifying an amount of charge of a capacitance of a touch sensor. The modified amount of charge results in a voltage at the capacitance being a first pre-determined voltage level. The method also includes applying a first pre-determined amount of charge to the capacitance. The application of the first pre-determined amount of charge to the capacitance modifies the voltage at the capacitance from the first pre-determined voltage level to a first charging voltage level. The method also includes determining a first voltage at a sampling capacitor. The first voltage is proportional to a difference between the first charging voltage level and a reference voltage level. The method also includes determining whether a touch and stylus input to the touch sensor has occurred based on the first voltage and a second voltage.

Abstract: In certain embodiments, an apparatus includes a touch sensor that includes a touch-sensitive area and a touch-sensor controller. The touch-sensor controller is operable to: scan two or more electrodes within the touch-sensitive area to determine a first location associated with an object within the touch-sensitive area, predict, based on the first location and one or more metrics, two or more next locations associated with the object, select, based on a first next location of the two or more next locations, a first region within the touch-sensitive area, select, based on a second next location of the two or more next locations, a second region within the touch-sensitive area, and scan two or more electrodes within the first region and two or more electrodes within the second region to determine a second location associated with the object. The second region is at least partially different from the first region.

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: In one embodiment, a stylus with 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 has one or more sensors for detecting movement of the stylus.

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, an apparatus comprises a sense unit and a drive unit. The sense unit is operable to sense a first signal from drive lines of a touch sensor. The touch sensor comprises the drive lines and sense lines arranged relative to the drive lines such that intersections of the drive lines and the sense lines form one or more capacitive nodes. The drive unit is operable to transmit a second signal based on the first signal to the sense lines such that transmission of the second signal changes the perceived capacitance of the one or more capacitive nodes.

Abstract: In one embodiment, a method includes receiving sensor data from one or more sensors in or on a stylus, the stylus including one or more electrodes and one or more computer-readable non-transitory storage media embodying logic for wirelessly transmitting signals to a device through a touch sensor of the device. The method includes generating a carrier signal and modulating the carrier signal to communicate the sensor data and wirelessly transmitting from the stylus to the device the carrier signal as modulated through the touch sensor of the device.

Abstract: In one embodiment, a method includes receiving at a stylus a receive signal from a device. The stylus includes one or more computer-readable media embodying logic, and the device includes a touch sensor. The receive signal is received at the stylus through the touch sensor of the device and one or more electrodes of the stylus. The method includes filtering the receive signal for processing by the logic and processing, by the logic, the receive signal as filtered.

Abstract: In one embodiment, a method includes receiving at a stylus a receive signal from a device. The stylus includes one or more computer-readable media embodying logic, and the device includes a touch sensor. The receive signal is received at the stylus through the touch sensor of the device and one or more electrodes of the stylus. The method includes determining whether a level of the receive signal substantially meets or exceeds a pre-determined threshold; if the level of the receive signal substantially meets or exceeds the pre-determined threshold, then transmitting the receive signal to the logic for processing; and, if the level of the receive signal does not substantially meet or exceed the pre-determined threshold, then filtering out the receive signal from processing by the logic.

Abstract: In one embodiment, a method includes detecting movement of a spring structure of a force sensor coupled to a center shaft of an active stylus; measuring a change of capacitance between electrodes of the force sensor; and determining an amount of force applied to the center shaft based on the change of capacitance.

Abstract: In one embodiment, a stylus receives a signal, the stylus being able to wirelessly transmit signals to and receive signals from a device, and the stylus having a plurality of electrodes disposed in a tip of the stylus. The stylus compares a first value of the signal to a first threshold and determines whether to start a timing period based at least in part on this comparison. If the timing period is started, the stylus compares a second value of the signal to a second threshold and determines whether to stop the timing period based at least in part on this second comparison. If the timing period is stopped, the stylus determines whether the duration of the timing period is within a pre-determined range of timing period values. If so, the stylus processes the signal.

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 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: In one embodiment, a method includes in an inductive-sensing mode, by a controller, applying an alternating-current (AC) signal on a first electrode of a capacitive touch sensor. The capacitive touch sensor is configured to operate in the inductive-sensing mode and a capacitive-sensing mode. The method also includes sensing a signal indicative of a magnetic field on the first electrode. The signal is due at least in part to a magnetic field generated by the object and the magnetic field is generated at least in part in response to the AC signal applied on the first electrode. The method also includes determining a position of the object generating the magnetic field based on the signal indicative of the magnetic field.

Abstract: In one embodiment, a stylus with 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 has one or more sensors for detecting movement of the stylus.

Abstract: A single-wire bootloader software architecture is disclosed that interfaces with any host device that has a serial port to program memory of a target device using only a single general-purpose I/O pin. The single-wire bootloader does not require any chip hardware resource modules. Instead, the single-wire bootloader implements a single-wire UART in software that monitors a single general-purpose I/O pin for commands from the host device.