Patent Description:
To utilize the full functionality of the pen, and not just inking, users must pair their pens with the companion devices (e.g., via Bluetooth) in existing systems. There are several ways in which Bluetooth pairing is possible, but some users do not pair their pens given the difficulties involved in current pairing processes and, therefore, do not get the benefit of the full functionality of the pen. <CIT> describes a touch sensor that can be used with a finger and/or a pen configured to provide a touch input to the touch sensor. The touch sensor involves touch capacitive touch sensing, or other touch and pen technologies, such as resistive, surface acoustic wave, bending wave, touch force, electromagnetic. Discrimination between intentional touches and unintentional touches on the touch surface can be performed using first criteria. For each touch identified as an intentional touch, discrimination between a finger touch and a pen touch can be performed using second criteria. During a mating process, the pen transmits a wildcard code to a touch sensor controller through a local connection; the controller transmits an identification code to the pen through a second (longer range) connection; and the pen transmits the identification code to the touch sensor controller through the first (local) connection. When a pen initially comes within range of the second communication connection, the pen and controller establish the communication connection. If the pen and controller have been previously mated (paired), the pen is commanded to emit the identification code previously established and stored on the controller's list. If the pen and controller have not been previously mated, the pen emits a wildcard drive code that is a generic code used for all compatible controller/ Host systems. <CIT> provides a method of copying, using a substrate, object data to a clipboard of a graphical user interface operating system, the substrate having a graphical representation of the object data disposed therein or thereon, the substrate also having coded data disposed therein or thereon, the coded data identifying a plurality of locations on the substrate, the coded data also identifying a layout of the graphical representation of the object data, the method including the steps of: receiving, from a sensing device and in a computer system, indicating data, the indicating data describing movement of the sensing device relative to the substrate, the indicating data also identifying the layout of the graphical representation of the object data, the sensing device, when moved relative to the substrate, adapted to read at least some of the coded data and generate, from the at least some coded data, the indicating data; retrieving, in the computer system and using the indicating data, the object data; and copying the object data to the clipboard. <CIT> relates to device pairing, e.g. between a computing device (e.g., companion device) and a stylus. The companion device can have a display and be configured to communicate in accordance with a wireless protocol. The stylus can be configured to transmit proximity information to the computing device when a user brings a tip of the stylus proximate to the display and be configured to supply wireless protocol identification information with the proximity information. The computing device can be configured to pair with the stylus over the wireless protocol using the wireless protocol identification information without requiring any additional action from the user on the computing device or the stylus. Once pairing is complete, the user can use click switch on the stylus to control the companion device. For instance, the user may use the click switch to launch an application on the companion device.

It is the object of the present invention to provide an improved method, one or more computer storage media and system for coupling a stylus to a computing device.

In <FIG>, the systems are illustrated as schematic drawings. The drawings may not be to scale.

Aspects of the disclosure provide a system and method for coupling a stylus and computing device in a "loose coupling" relationship. Based on a tip of a stylus being brought proximate to a display of a computing device, the stylus and computing device are configured to exchange respective wireless protocol identifiers and security keys. Each device stores the exchanged identifiers and security keys, enabling the described coupling, but without formal or traditional pairing. User input to the stylus is received by the stylus, and indicates that a signal is to be sent to a coupled computing device using a wireless protocol other than the one used to exchange the identifiers and security keys. The stylus transmits the indicated signal to the computing device using the wireless protocol identifier of the computing device. Based on receiving a signal from the coupled stylus, the computing device performs an operation based on the signal. Performed operations may be related to the relationship between the stylus and computing device (e.g., initiating full, formal pairing, etc.) and/or associated with other functionality of the computing device (e.g., executing and/or interacting with applications, etc.). In this manner, the devices are coupled through the exchange of identifiers and security keys via a wireless protocol (e.g., a short range wireless protocol) without pairing, while other communication may occur later via another wireless protocol (e.g., a wireless protocol with a longer range than the short range wireless protocol).

The described systems and/or methods are designed to, among other items, improve the initial pairing and/or connecting experience for the user, remove the need for factory pre-pairing, and create a seamless coupling and/or connecting experience with respect to new or replacement pen devices (e.g., styluses, pens, etc.) through the formation initially of loosely coupled connections between pen devices and companion devices, such as tablets or phones, as described herein. The described systems and/or methods are configured to maintain compatibility with previous pen devices/companion devices as necessary.

The described system operates in an unconventional way by providing full pen device functionality that roams with the user's pen device, whereby it is enabled across multiple computing devices. To enable roaming seamlessly across devices, the present disclosure provides the loosely coupled connection model which is different from formal pairing. Particularly, it should be understood that "coupling" and "pairing" refer to different processes and/or states. The coupling of pen devices and companion devices and use of loosely coupled connections refer to the relationship formed between the devices based on an exchange of identification and security information prior to pairing, as described herein. Further, the pairing of pen devices and companion devices generally refers connecting the devices using a standard Bluetooth pairing process as is understood in the art. Coupling of a pen device to a companion device may occur prior to and/or independently of a pairing, bonding, or other connection or linkage of the devices.

Users that buy a stylus with their companion device expect the stylus to work with the companion device. User satisfaction can quickly diminish if the user has to read instructions and take various manual, non-intuitive actions to get the stylus and companion device to operate cooperatively. The present disclosure provides several seamless solutions so that, from the user's perspective, the stylus and the companion device work as expected with little or no user intervention/involvement.

In this manner, loosely coupling the pen and computing devices without pairing simplifies human-machine interaction by requiring fewer, or no, manual steps than traditional pairing. Further, the loose coupling configuration improves the underlying functioning of the computing device by enabling functionality previously only available after traditional pairing.

<FIG> collectively illustrate a use case scenario explained relative to a system <NUM>. In this case, system <NUM> involves a stylus <NUM> and a companion device (e.g., computing device) <NUM> having a display <NUM>. The stylus <NUM> includes a body <NUM>, a sensing tip <NUM>, and a power source, such as a battery <NUM>.

For purposes of explanation, this scenario begins relative to Instance One when a user <NUM> powers up the stylus <NUM> for the first time, such as by inserting the battery <NUM> into the stylus. For instance, the user may purchase the stylus <NUM> and the companion device <NUM> together as a set, open the packaging, and install the battery. In other cases, the battery may already be installed and the user may simply pick up the stylus for initial use.

As shown in Instance Two, upon unwrapping the stylus <NUM> and powering it up, the user <NUM> may intuitively try to write (e.g., ink) on the companion device <NUM>'s display <NUM> (or otherwise interact with the display) with the stylus. As the stylus's sensing tip <NUM> interacts (e.g., approaches and/or touches) the display <NUM>, sensed information can be communicated between the stylus <NUM> and the companion device <NUM> as indicated generally at <NUM>. The sensed information can be communicated in various wireless formats (e.g., via an electrostatic signal). Generally, these formats rely on close proximity of the devices involved, such as within a couple of inches. For instance, the stylus <NUM> can generate signals that convey the sensed information and that are picked up by the companion device <NUM> via a proximity sensing component, such as a digitizer <NUM> underlying the display <NUM> as shown by cut-away <NUM>.

Normally, this sensed information <NUM> can relate to pressure information of the sensing tip <NUM> on the display <NUM>, acceleration information relating to the sensing tip, etc. However, the present implementations may include additional information with the sensed information <NUM>. This additional information can be wireless format (e.g., protocol) identification information about other wireless capabilities of the stylus <NUM>. For instance, the stylus may have Bluetooth capabilities, and the wireless format identification information can relate to these Bluetooth capabilities. For example, the wireless format identification information can include a Bluetooth unique identification (e.g., manufacturing identification number or Bluetooth address) or the Bluetooth unique identification can be derived from the available wireless format identification information.

In Instance Three, the companion device <NUM> can use the Bluetooth unique identification received with (or derived from) the sensed information to couple with the stylus <NUM> as described herein, priming the companion device <NUM> and stylus <NUM> for interaction and/or communication prior to subsequent Bluetooth pairing, or entirely without subsequent Bluetooth pairing. It should be understood that, if the stylus <NUM> is loosely coupled to the companion device <NUM>, a user may still pair and/or bond the stylus <NUM> to the companion device <NUM>. The stylus <NUM> may be configured with two identifying addresses (e.g., Bluetooth addresses, etc.) to achieve this (one address for loose coupling and the second address for pairing and bonding). Coupling may include the companion device <NUM> storing the Bluetooth unique identification of the stylus <NUM> and responding to the stylus <NUM> by providing Bluetooth unique identification of the companion device <NUM>. The stylus <NUM> may be configured to store the Bluetooth unique identification of the companion device <NUM> for future use during subsequent Bluetooth pairing or other use of Bluetooth communication between the coupled devices. The stylus <NUM> can respond to the initial communication as indicated generally at <NUM> and coupling, or priming, can be accomplished as described herein. This wireless protocol identification information allows subsequent pairing or related communication to be accomplished without the user <NUM> taking any affirmative steps, such as going to a settings menu on the companion device, selecting Bluetooth, selecting an individual device, and selecting that the individual device be paired; thereby improving the user experience by reducing the amount of user interaction required for pairing.

It should be understood that the companion device <NUM> may be configured to enable blocking loosely coupled connections entirely. Such configurations may be based on an organization-mandated policy or the like; by default, the loose coupling feature may be enabled.

In some examples, a graphical user interface (GUI) may be presented on companion device <NUM> that indicates that pairing has been commenced with the stylus <NUM>. This example first couples the companion device <NUM> and stylus <NUM>, and then performs associated Bluetooth communications, such as pairing, without any user input and instead relies on the fact that the user is using the stylus to interact with the companion device as evidence that the user wants to proceed. Further, a GUI of the companion device <NUM> may include a "Bluetooth and other devices" settings page that displays loosely coupled styluses (e.g., stylus <NUM>, etc.) for interaction with a user. If the same stylus is loosely coupled to the companion device <NUM> and is then paired to the companion device <NUM> (or vice versa) the list of devices may display a unified instance of the stylus.

Some of the present implementations utilize out-of-band communications relating to display interactions to transfer information about other wireless formats of the interacting device/apparatus (e.g., stylus <NUM>) to the display device (e.g., companion device <NUM>). The companion device can use the information about the interacting device to establish coupling and/or communication over another wireless format, rather than relying on manual actions from the user to establish the coupling and/or communication.

<FIG> shows that communication subsequent to the coupling can be accomplished between the stylus <NUM> and the companion device <NUM> via the second wireless format (e.g., in this example, Bluetooth). As shown in example Instance Four, if the user <NUM> subsequently activates a sensor or other interface of the stylus <NUM> associated with the second wireless format, the stylus initiates pairing or otherwise communicate with the companion device <NUM> based on the coupling and cause the companion device to launch a drawing application (or take another action). As shown in example Instance Five, the drawing application (e.g., drawing application GUI) <NUM> is launched and ready for the user to use on the companion device <NUM> before the stylus <NUM> even approaches the companion device's display <NUM>.

As an alternative to launching an application, the user <NUM> may select an 'eraser' feature on the stylus <NUM> (e.g., via a button press), and this information is communicated to the companion device <NUM> based on the stored identification information shared during coupling so that when the stylus's sensing tip <NUM> approaches the display <NUM>, visual content is erased rather than drawing/inking new content.

<FIG> shows system <NUM> and offers details about stylus <NUM> and/or companion device <NUM>. The stylus <NUM> and the companion devices <NUM> are in and of themselves types of computing devices. In this case, system <NUM> includes several example companion devices <NUM>(<NUM>)-<NUM>(<NUM>). Companion device <NUM>(<NUM>) is manifest as a tablet type device similar to device <NUM> of <FIG>, companion device <NUM>(<NUM>) is manifest as a smart phone type device. Companion device <NUM>(<NUM>) is manifest as a notebook computer type device and device <NUM>(<NUM>) is manifest as a digital whiteboard type device.

Two example device configurations <NUM>(<NUM>) and <NUM>(<NUM>) are illustrated that can be used to implement stylus <NUM> and/or companion devices <NUM>. Briefly, configuration <NUM>(<NUM>) represents an operating system centric configuration, and configuration <NUM>(<NUM>) represents a system on a chip configuration (SOC). Configuration <NUM>(<NUM>) is organized into one or more applications <NUM>, operating system <NUM>, and hardware <NUM>. Configuration <NUM>(<NUM>) is organized into shared resources <NUM>, dedicated resources <NUM>, and an interface <NUM> therebetween.

In either configuration <NUM>(<NUM>) or <NUM>(<NUM>), the stylus <NUM> and/or companion device <NUM> can include storage/memory (e.g., computer-readable storage media) <NUM>, a processor <NUM>, a battery <NUM> (or other power source), and input assemblies <NUM>. In this case, the input assemblies are manifest as a click switch <NUM>. Both configurations can also include sensors <NUM>. Examples of sensors can include: pressure sensors, proximity sensors, accelerometers, gyroscopes, inertial sensors, capacitors, magnetometers, and/or microphones, among others. A specific sensor that is discussed in detail is a pressure sensor. Either configuration can include a wireless communication component(s) <NUM> and/or a facilitation component <NUM>. The communication component <NUM> can include transmitters and/or receivers for communicating over various electromagnetic wavelengths in compliance with various formats (e.g., protocols), such as <NUM> to <NUM> in the case of Bluetooth.

The sensing tip's pressure sensors may be positioned to detect when sensing tip <NUM> contacts display <NUM>. Similarly, electrostatic receivers detect proximity of the sensing tip to a surface as the tip approaches the surface but before physical contact via capacitance or other mechanism. In some configurations, the electrostatic receivers function as proximity detectors to the companion device <NUM> so that the stylus <NUM> transmits proximity information and wireless format identification information to the companion device <NUM>.

The companion device <NUM> can include a proximity sensing component manifest as a 'pen sensor' (e.g., a sensor <NUM>) configured to receive the proximity information and wireless format identification information from the stylus <NUM>. The pen sensor can be associated with the companion device's display <NUM> (designated in <FIG>) or the pen sensor can be independent of the display. For instance, the pen sensor is integrated into the display as a display component. In another case the pen sensor is associated with the display as a separate component. For example, the display is manufactured as a display module and then the pen sensor is bonded to the display module in a subsequent process. In still another configuration, the pen sensor is a component of the companion device that is not physically associated with the display.

In the illustrated configuration of the stylus <NUM>, the sensing tip <NUM> protrudes from one end of the body <NUM>. Other implementations may employ sensing tips from both ends of the body and/or within the body. Further, sensing tips can be employed on other form factors besides the illustrated 'pen-like' configuration.

The communication component <NUM> can allow the stylus <NUM> to communicate with various companion devices, such as the illustrated companion devices <NUM>(<NUM>)-<NUM>(<NUM>). The communication component can include a receiver and a transmitter and/or other radio frequency circuitry (and/or other components, such as analog-to-digital converters, rectifiers, etc.) for communicating via various formats, such as cellular, Wi-Fi (IEEE <NUM>. xx), Bluetooth, etc. Example communication components are described below relative to <FIG>.

Instances of facilitation component <NUM> can occur on the stylus <NUM> and/or companion device <NUM>. In some implementations, the facilitation component <NUM> is manifest as part of the operating system <NUM>, application <NUM>, an application part, and/or an application program interface, among other options. The functionality performed by the facilitation components on various devices may be similar or different. For instance, in one case, the facilitation component on the stylus <NUM> stores the wireless format identification information of the stylus <NUM>, causes this information to be communicated to the companion device <NUM>, receives wireless format identification information from the companion device <NUM>, and stores the received identification information from the companion device <NUM>. In contrast, the facilitation component <NUM> on the companion device may identify (or otherwise distinguish) the sensor information from the wireless format identification information of the stylus <NUM>, process the wireless format identification information, cause the communication component to store the wireless format identification information, communicate wireless format identification information of the companion device <NUM> to the stylus <NUM>, and, based on coupling with the stylus <NUM> as described herein, subsequently contact the stylus's communication component and begin the pairing process as defined by the Bluetooth protocol (or other protocol) and/or otherwise communicate with via the Bluetooth protocol (or other protocol). Once pairing is complete or another method of communication is established based on the coupling, the facilitation component <NUM> can facilitate actions on the companion device <NUM> upon receiving Bluetooth communications from the stylus <NUM>. For instance, the user <NUM> may select an 'erase' function on the stylus. This may cause the stylus <NUM> to communicate to the companion device <NUM> with which it is coupled and the 'erase' function information can be communicated over Bluetooth communications to the companion device. The facilitation component can then cause the stylus's functionality to switch from 'draw' to 'erase' on the companion device as the user engages the display with the stylus. Of course, the facilitation component can cause other actions (whether predefined or user defined) upon receiving information from the stylus received via Bluetooth communications.

Stylus <NUM> and companion devices <NUM>(<NUM>)-<NUM>(<NUM>) are considered to be computing devices. The term "device," "computer," or "computing device" as used herein can mean any type of device that has some amount of processing capability and/or storage capability. Processing capability can be provided by one or more processors <NUM> that can execute data in the form of computer-readable instructions to provide a functionality. Data, such as computer-readable instructions and/or user-related data, can be stored on storage <NUM>, such as storage that can be internal or external to the computer.

As mentioned above, configuration <NUM>(<NUM>) is considered to be an SOC type design. In such a case, functionality provided by the device can be integrated on a single SOC or multiple coupled SOCs. One or more processors 324can be configured to coordinate with shared resources <NUM>, such as memory/storage <NUM>, etc., and/or one or more dedicated resources <NUM>, such as hardware blocks configured to perform certain specific functionality. Thus, the term "processor" as used herein can also refer to central processing units (CPUs), graphical processing units (GPUs), controllers, microcontrollers, processor cores, or other types of processing devices.

Generally, any of the functions described herein can be implemented using software, firmware, hardware (e.g., fixed-logic circuitry), or a combination of these implementations. The term "component" as used herein generally represents software, firmware, hardware, whole devices or networks, or a combination thereof. In the case of a software implementation, for instance, these may represent program code that performs specified tasks when executed on a processor (e.g., CPU or CPUs). The program code can be stored in one or more computer-readable memory devices, such as computer-readable storage media. The features and techniques of the component are platform-independent, meaning that they may be implemented on a variety of commercial computing platforms having a variety of processing configurations.

<FIG> shows additional details about one example SOC implementation of stylus <NUM>. The stylus's sensing tip <NUM> is touching display <NUM> of companion device <NUM>(<NUM>). Illustrated elements of the companion device include facilitation component <NUM>, storage <NUM>, a Bluetooth address generation algorithm <NUM>, a pen sensor <NUM>(N), and a communication component <NUM>.

This particular implementation of stylus <NUM> includes two separate printed circuit boards, PCB <NUM>(<NUM>) and PCB <NUM>(<NUM>), powered by two separate batteries <NUM>(<NUM>) and <NUM>(<NUM>), though the functionality could be achieved on a single integrated PCB powered by a single battery. In this case, battery <NUM>(<NUM>) is manifest as a AAAA battery generating <NUM> volts and battery <NUM>(<NUM>) is manifest as two <NUM> button batteries connected in series to generate <NUM> volts.

PCB <NUM>(<NUM>) includes an ASIC <NUM> and a signal generator <NUM>(<NUM>) for generating signals of specific frequencies. Sensor tip <NUM> includes a pressure sensor <NUM>(<NUM>) that is connected to the ASIC <NUM>. The ASIC <NUM> is also connected to battery <NUM>(<NUM>) and selectively to ground <NUM>. In this case, signal generator <NUM>(<NUM>) is manifest as an oscillator <NUM>(<NUM>) and the ASIC <NUM>. The ASIC <NUM> also includes storage 322A that has wireless protocol identification information <NUM> that is manifest as a device serial number <NUM>.

PCB <NUM>(<NUM>) includes another ASIC <NUM> and a signal generator <NUM>(<NUM>) in the form of an oscillator <NUM>(<NUM>). In this case, the ASIC <NUM> can function as a Bluetooth radio. The ASIC <NUM> can include storage 322B that has a Bluetooth random static address (Bluetooth (BT) address) <NUM> stored thereon. The ASIC <NUM> is driven by two <NUM> button batteries <NUM>(<NUM>)A and <NUM>(<NUM>)B. The batteries also drive a power on indicator assembly <NUM>. A user activatable input assembly <NUM> in the form of click switch <NUM> is connected to the ASIC <NUM>. ASIC <NUM> and the signal generator <NUM>(<NUM>) can function as a communication component (<NUM>, <FIG>). Similarly, ASIC <NUM> and signal generator <NUM>(<NUM>) can function as a communication component, or alternatively, ASIC <NUM>, signal generator <NUM>(<NUM>), ASIC <NUM>, and signal generator <NUM>(<NUM>) can be viewed as a single communication component.

Traditionally, Bluetooth pairing between the stylus <NUM> and the companion device <NUM>(<NUM>) requires multiple, manual steps to be performed by the user, such as going to a settings menu, finding the Bluetooth option, identifying the device to be paired, etc. Further, the user may not even know that the stylus has Bluetooth capabilities and thus not even know to complete the pairing process. The present disclosure describes a process of loosely coupling the stylus and companion device that may be used instead of, or in conjunction with, a standard Bluetooth pairing process or other similar pairing process.

In this example, the device serial number <NUM> is assigned to the stylus <NUM> during manufacture, such as by an entity manufacturing the stylus or a component thereof, such as the PCB <NUM>(<NUM>). The device serial number <NUM> can be processed by Bluetooth address generation algorithm <NUM> to produce the Bluetooth address <NUM>. Such an example algorithm is the SHA1 or SHA256 algorithm. An example application of the SHA1 Bluetooth address generation algorithm is provided below. The Bluetooth address <NUM> can be thought of as the over the air address or GAP address (e.g., the address used to communicate with the Bluetooth radio provided by the ASIC <NUM>).

Example Bluetooth address generation algorithm <NUM> includes:.

In the present scenario, the ASIC <NUM> is configured to perform Bluetooth loose coupling operations as described herein. Other implementations using other wireless protocols can perform operations to implement loose coupling that are compliant with the individual wireless protocol. Upon interaction with display <NUM>, the pressure sensor <NUM>(<NUM>) can convert mechanical pressure on the sensing tip <NUM> to an output signal (e.g., TIP_OUT) pressure value <NUM>. The ASIC <NUM> can receive the output signal pressure value <NUM> and represent the output signal pressure value by modulating signals generated by the signal generator <NUM>(<NUM>). In this case, the signal generator is manifest as oscillator <NUM>(<NUM>). The ASIC <NUM> can further modulate the signals generated by the signal generator <NUM>(<NUM>) to convey device serial number <NUM>.

The companion device's pen sensor <NUM>(N) operating cooperatively with communication component <NUM> can receive the modulated signals from the signal generator <NUM>(<NUM>) of stylus <NUM>. The companion device's facilitation component <NUM> can identify portions of the signals conveying tip sensing information and portions of the signals conveying the serial number <NUM> and/or an associated Bluetooth low energy (BLE) address of the stylus <NUM>. The facilitation component can process the serial number <NUM> with the Bluetooth address generation algorithm <NUM> (e.g., the same algorithm that was used to generate the Bluetooth address <NUM> for the stylus <NUM>). The facilitation component can compare the Bluetooth address <NUM> to a listing of Bluetooth devices (stored in storage <NUM>) that the companion device is already loosely coupled with and/or has already paired with. If the stylus is already on the list of coupled or paired devices, the facilitation component can stop processing. If this is the initial use of the stylus <NUM> with the companion device <NUM>(<NUM>) (e.g., the stylus is not on the list of coupled or paired devices), the facilitation component can cause the communication component to use the Bluetooth address <NUM> to contact the stylus <NUM>. The communication component can then communicate with the stylus in accordance with the coupling process described herein. Once coupling is complete, the user can use click switch <NUM> to cause the stylus <NUM> to pair with or otherwise communicate with the companion device <NUM>(<NUM>) in order to control the companion device <NUM>(<NUM>). For instance, the user may use the click switch to launch an application, switch stylus contact from 'drawing' to 'erasing', or 'add a note,' among others.

From one perspective, the Bluetooth address <NUM> (e.g., GAP address) generated from serial number <NUM> (e.g., Pen ID) can be used to enable out of band or loose coupling and/or pairing since the serial number can be communicated to the companion device operating system (<NUM>, <FIG>) via stylus human interface device (HID) reports when the stylus's sensing tip <NUM> is interacting with the display <NUM> of the companion device <NUM>(<NUM>). An operating system driver or application can decode the serial number to the Bluetooth address using the same Bluetooth address generation algorithm and initiate the coupling process described herein by passing the Bluetooth address to the appropriate operating system application program interface (API). If the Bluetooth address decoded from the serial number is already coupled or paired, then it can stop the process. Similar implementations can be accomplished for other wireless formats/protocols.

In this implementation, the serial number <NUM> can be smaller (e.g., less bytes) than the Bluetooth address <NUM>. Thus, communicating the serial number <NUM> to the companion device <NUM>(<NUM>) rather than the Bluetooth address <NUM> is less resource intensive for the stylus <NUM>. The companion device <NUM>(<NUM>) thus obtains the Bluetooth address indirectly by processing the received serial number <NUM> with the Bluetooth address generation algorithm <NUM>, such as the above mentioned SHA1 or SHA256. Other implementations can instead convey the Bluetooth address directly to the companion device via signal generator <NUM>(<NUM>).

Further, the stylus <NUM> may be configured to obtain a BLE address, or other similar address, and/or security key(s) of the companion device <NUM>(<NUM>) during the loose coupling process. It is intended that the BLE address is obtained via the pen tip <NUM> from the digitizer of the display <NUM> while inking. This address may be stored in non-volatile memory (e.g., storage 322A, 322B, etc.) until a different address is obtained, at which time the old address may be replaced. Alternatively, the stylus <NUM> may be configured to retain multiple host BLE addresses for use as described herein. Further, multiple styluses may be paired and bonded and/or loosely coupled to one companion device <NUM>(<NUM>) at the same time and the click functionality may work for each stylus on that companion device <NUM>(<NUM>). The companion device <NUM>(<NUM>) and/or stylus <NUM> may be configured to enable users to remove any stylus-companion device association.

The stylus <NUM> and associated companion device <NUM>(<NUM>) are configured to provide functionality based on being coupled or paired and using Bluetooth wireless communications. For instance, user input through the assembly <NUM> of the stylus <NUM> may cause a signal to be communicated to the companion device <NUM>(<NUM>), further causing the companion device <NUM>(<NUM>) to perform an associated operation as described herein. Functionality enabled by the stylus <NUM> and companion device <NUM>(<NUM>) may be based on the use of stylus-based communication services that may be interpreted by the companion device <NUM>(<NUM>).

In an exemplary embodiment, these stylus-based communication services may use vendor-specific base UUID E766xxxx-3F85-40F5-<NUM>-284E9095A1E2. Exemplary service details are provided below, though the disclosure is operable with other configurations. In some examples, services may include a pen service (e.g., service UUID 0x1000, etc.) configured to report button activity and battery status, a "click" service characteristic (e.g., service UUID 0x2000, etc.), a "pen ID" service characteristic (e.g., service UUID Ox2001, etc.), a "pen serial number" service characteristic (e.g., service UUID 0x2002, etc.), a "pen descriptor" service characteristic (e.g., service UUID 0x2003, etc.), a "service session key" service characteristic (e.g., service UUID Ox0010, etc.), and/or an "implied sign counter" service characteristic.

In some examples, the "click" service characteristic may include a <NUM>-byte data field that is openly notifiable but not readable or writable. The field may include a button identifier that indicates buttons of the stylus being clicked (e.g., a byte <NUM> with data values of 0x00 for "no button", Ox01 for "click button", and Ox10 for a "barrel button <NUM>", etc.). A "click type" data field (e.g., a byte <NUM> of the click service data field, etc.) may indicate a type of click that has been performed. Exemplary click types and associated data codes are provided below.

A given button uses either the pressed/released messages or the single/double/press-hold messages depending on whether button processing is done in the peripheral or on the host. In an example, the tail click button of the stylus may use the single/double/press-hold click types.

Further data fields of the click service data field may include a "battery level" data field (e.g., a byte <NUM> of the data field that provides the battery life remaining in a percent data value, etc.). The battery level data field may further report that no reading is available (e.g., a value of 0xFF, etc.) and/or report the battery level without an associated click (e.g., by setting the button identifier to a "no button" value, etc.). The click service data field may also include reserved bytes (e.g., a byte <NUM> of the data field, etc.). Such reserved bytes may be set to zero or other values.

In some examples, a portion of the click service data field (e.g., bytes <NUM> through <NUM>, etc.) of the click service data field may be associated with an encryption signature (e.g., a count value and an Advanced Encryption Standard cipher-based message authentication code (AES-CMAC) according to Bluetooth Core <NUM>, section <NUM>, Part f, <NUM>. <NUM>, etc.).

The pen ID service characteristic of the pen service as described herein may be a four-byte data field that contains the pen ID of the pen device. It may be configured to be openly readable but not writeable. Further, the pen serial number service characteristic of the pen service may be a <NUM>-byte data field containing the serial number of the stylus in an ASCII format. Unused bytes may be set to zero. It may be configured to be openly readable but not writable.

The pen description service characteristic of the pen service as described herein may be a one-byte data field that contains data indicating whether the associated stylus is rechargeable (e.g., a "<NUM>" indicating the device is not rechargeable, a "<NUM>" indicating the device is rechargeable, with other values <NUM>-<NUM> reserved, etc.). The data field may be configured to be openly readable but not writeable.

The service session key characteristic of the pen service as described herein may be a four-byte writable field for storing a Service Session Key. Once connection between pen and host is established, the host sends a new randomly generated Service Session Key to the pen. The pen remembers one Service Session Key per each service which has signed data exchange. This key is only stored for duration of one connection. Once the associated connection is dropped, a new key must be received by the stylus for future connections.

The implied sign counter characteristic of the pen service as described herein may be a four-byte variable for storing data associated with a sign counter. Once a connection between the stylus and host is established, the host and stylus each allocate a <NUM>-bit sign counter with initial value <NUM>. Separate sign counters are maintained for every service that has an active signed data exchange. The first message from the stylus is defined to have a sign counter value <NUM>. Each sign counter is incremented before every new message is sent by the stylus. The host does not send a sign counter value to the stylus. The host validates that all messages from the stylus have a sign counter value greater than in previous accepted message in the same connection and the same service. The sign counters associated with a connection are only persisted during the connection duration.

In some examples, data size and content for a button click notification and/or other associated notifications from the stylus may include <NUM> bytes for button click data, <NUM> bytes for a sign counter, and <NUM> bytes for a Service Session Key. Initial signing procedure between the stylus and host may include a message in the following pattern: Service Session Key (<NUM> bytes) | | Button Click Data (<NUM> bytes) | | Sign Counter (<NUM> bytes).

Sign counters are configured to be unique per service to prevent replay attacks within the same service and connection. Random service session keys prevent replay attacks where data from one connection or service is replayed in another connection or service. Implementing the described signing procedure and notification procedure may prevent malicious replay, sniffing, and spoofing attacks that can lead to denial of service (e.g., when pen button clicks are not received by the host, etc.) or malicious injection attacks (e.g., when unauthorized pen button clicks are injected into the system, etc.).

<FIG> shows a flowchart describing exemplary operations of a system including a pen device and an associated companion device. The pen begins in "shipping mode" (e.g., an inactive mode, etc.) at <NUM> and, upon docking to the companion device, the pen goes to "operational mode" (e.g., an active mode, etc.) at <NUM>. The pen may transition from being docked (at <NUM>) to being undocked (at <NUM>) as it is used by a user.

If the user is logged in when the pen is docked at <NUM>, a loose coupling association may be formed between the pen and the companion device as described herein. In this case, the association may be formed via near field communication (NFC) or other short ranged wireless communication (e.g., via a wireless local area network (LAN) controller (WLC), etc.) at <NUM>. In some examples, the docking-based association may occur in less than <NUM> milliseconds after the pen is docked to the companion device.

Alternatively, or additionally, if the user is logged in when the pen is undocked at <NUM> and used to ink on the screen of the companion device, the loose coupling association may be formed between the pen and the companion device based on an electrostatic (ES) transmission of data as described herein at <NUM>. This "uplink" communication (e.g., a digitizer-to-pen ES communication channel, etc.) is used to facilitate connecting and/or re-connecting to the companion device on which the pen is inking by sharing identification information and/or secure key information as described herein. In some examples, the ES-based association may occur in less than <NUM> milliseconds from the host to the pen and less than <NUM> milliseconds based on continuous inking input.

In an example, if a user has docked a pen to a first device for charging but has also used it recently for inking on a second device, the coupling association is with the second device until a user has inked on the first device or explicitly paired or reconnected to the first device. Alternatively, the pen may default to the device to which it is docked, rather than the device on which it has most recently inked. Further, when a user moves a pen from a first device to a second device and back, BLE functionality is available immediately after receiving first device's address. It is not necessary to receive an authentication key or keys again before BLE functionality is enabled on the first device. In some examples, this may be valid for at least <NUM> companion devices (the pen stores keys for at least <NUM> companion devices).

Once associated, the buttons and/or other interfaces of the pen may be used to cause the companion device to perform operations as described herein. If the pen is docked and associated at <NUM> and the button is pressed, then the companion device may be configured to do nothing at <NUM>. However, if the pen is undocked and associated at <NUM> and the button is pressed, the pen may directly advertise to the associated companion device, based on the most recently obtained BLE address of the companion device, at <NUM> and send a message associated with he pressed button at <NUM>. In some examples, following a pen button press, the pen sends the button event to the associated host device and the button events are translated and injected into the input stack. Alternatively, or additionally, if the button press exceeds <NUM> seconds, or, in other examples, a different threshold, the pen may transition into un-directed advertising at <NUM> in order to perform a Bluetooth pairing operation according to the known Bluetooth processes (e.g., 1st time pairing processes at <NUM> including user consent at <NUM>, re-pairing processes at <NUM>, etc.), resulting in the pen being paired at <NUM>. Alternatively, or additionally, in examples where no BLE address is available (e.g., the pen is not associated with a companion device, etc.) when connection is desired, the pen may indicate an error condition by blinking the LED.

It should be understood that a pen configured as described herein may be used with legacy companion devices or companion devices that are not uplink-enabled (e.g., configured for loose coupling, etc.) by using known Bluetooth pairing processes. Further, a companion device configured as described herein may also be paired with legacy pens or pens that are not uplink-enabled using known Bluetooth pairing processes.

It should be understood that, when the pen enters un-directed advertising mode via button press and hold at <NUM>, the pen may advertise in a high-power mode for <NUM> minutes or another defined time period. If pairing does not occur within the time period, the pen may stop advertising. Further, when pen enters advertising mode, it advertises for the specified duration, overriding any sleep timer or the like.

In some examples, following a <NUM>-second tail button press, the pen goes into advertising mode even if it is associated to a companion device in range (i.e., via a loosely coupled connection). If the pen is loosely coupled to a device, the long-press event may be sent to the companion device before going into advertising mode. If the pen is paired/connected to a companion device in range and the button is pressed for <NUM> seconds, the pen does not lose its bonding information and does not go into advertising mode, similar to other pen devices.

<FIG> are sequence charts that illustrate exemplary operations of a system <NUM> according to an embodiment. The system includes a host device (e.g., companion device <NUM>, etc.), also described as a companion device below, with a pen service, a digitizer driver (e.g. digitizer HID TLC with adaptation driver, etc.), and associated digitizer firmware. Further, the system includes a pen device (e.g., stylus <NUM>, etc.) with pen tip and pen Bluetooth components.

<FIG> illustrate several processes of the system as described herein. A first process, illustrated in <FIG>, occurs when the digitizer is powered on, when a digitizer-initiated-reset notification is received, or when the screen associated with the digitizer unlocks. The pen service sends the host BLE address to the digitizer driver at <NUM>. The digitizer driver sends the received host BLE address to the digitizer firmware at <NUM>. Finally, the digitizer firmware caches the host BLE address at <NUM>.

Another illustrated process in <FIG> occurs when the pen tip component is in range of the digitizer panel. At <NUM>, the pen tip component sends a pen ID to the digitizer firmware. If the host BLE address is cached in the digitizer firmware, the digitizer firmware sends the cached host BLE address to the pen tip at <NUM>. If the host is a new host and an authentication key is already cached, the pen tip component sets the host as the current host at <NUM>.

The digitizer firmware then sends the received pen ID to the digitizer driver at <NUM>. At <NUM>, the digitizer driver maps the pen ID to the pen BLE address and, at <NUM>, sends the pen BLE address to the pen service. If the screen of the host device is unlocked, the pen service fetches a cached secret key or generates a new secret key at <NUM>. The pen service then sends the pen BLE address and key to the digitizer driver at <NUM>. The digitizer driver maps the pen BLE address to the pen ID at <NUM> and sends the pen ID and key to the digitizer firmware at <NUM>. Using the pen ID, the digitizer firmware sends the key to the pen tip component at <NUM>. If the key is different than a key stored by the pen device, the pen tip component persists with the host BLE address and key at <NUM>. This process may result in the pen and host device being loosely coupled. Following this association of pen to host device, all Bluetooth functionality is sent to this associated host. Association of pen to host device remains until the pen is associated or connected to a different host device. If there is a current BLE transaction in process, it is terminated; if this happens during a key-press event, termination would occur after the key-up event.

Another process is described in <FIG> that occurs when a pen button is clicked or another wake-up event initiated with respect to the loosely coupled pen device and host device. At <NUM>, during a fixed loop duration, the pen Bluetooth component sends directed advertisement to the pen service. Upon receiving the directed advertisement, the pen service connects to the pen Bluetooth at <NUM>. The pen service then generates a random <NUM>-bit session key at <NUM> and writes the session key to the pen Bluetooth at <NUM>. In some examples, the pen service initializes a sign counter to zero at <NUM> for use in communications with the pen device as described herein. The pen service enables notifications of the pen Bluetooth at <NUM> and the pen Bluetooth responds with a pen report at <NUM>. The pen report may include a variety of data, such as button event data or other user input data, battery level data, and/or telemetry data. At <NUM>, the pen service validates a signature and sign counter received with the pen report to verify the communications with the pen device. The signature may be based on a previously generated signing key as described herein. If the pen report indicates that an operation is to be performed by the host device and/or, specifically, the pen service, the pen service performs an operation based on the report at <NUM>. Alternatively, the pen service may cause another component of the host device to perform the indicated operation. For instance, operations may include injecting button click data when button click data is present in the report and/or reporting battery status of the pen device when battery data is present in the report. At <NUM>, the pen service updates the locally stored pen information based on the pen report as well (e.g., updating the last seen timestamp, pen friendly name, etc.). The host device may be configured to only receive loosely coupled Bluetooth connections from associated and authenticated pens (e.g., connections from new pens which have not inked on the host or docked to it are rejected, etc.). A user may remove a loosely coupled pen from the host device. Upon removal, Bluetooth functionality from the pen is no longer acted upon by the host device until a new association or pairing takes place.

Yet another process in <FIG> is described that occurs when the screen of the host device is locked. At <NUM>, the pen service sends a "clear host BLE address" command to the digitizer driver and, at <NUM>, the digitizer driver forwards the "clear host BLE address" command to the digitizer firmware. At <NUM>, the digitizer firmware clears the cached host BLE address.

<FIG> show flowcharts describing exemplary operations of a computing device and an associated stylus respectively according to an embodiment. In <FIG>, the flowchart <NUM> illustrates operations of a computing device according to an embodiment are described. At <NUM>, the computing device receives a stylus wireless protocol identifier in a first signal from a stylus. The signal is communicated using a communication channel that is not associated with the wireless protocol with which the received stylus wireless protocol identifier is associated. For instance, the computing device may receive a BLE address of the stylus via an ES communication channel.

At <NUM>, based on the receiving the stylus wireless protocol identifier, the computing device transmits a second signal including a wireless protocol identifier of the computing device and a security key to the stylus via the communication channel. The computing device and stylus may each store the wireless protocol identifiers of the respective devices and the security key, such that the computing device and stylus are loosely coupled as described herein. It should be understood that, while <NUM> describes sharing single a single security key, in some examples, multiple security keys may be shared.

At <NUM>, based on receiving a third signal associated with user input from the coupled stylus via the wireless protocol, the computing device is configured to perform an operation based on the third signal. In some examples, the operation performed may include pairing the stylus and computing device (e.g., Bluetooth pairing, etc.). Other operations may include operations based on button presses or other sensor input events on the stylus. The third signal may be a directed advertising signal from the stylus that uses the wireless protocol identifier of the computing device to directly target the computing device with the third signal, enabling the user input from the stylus to cause the computing device to perform operations that would not be possible unless the computing device and stylus were paired or otherwise coupled as described herein.

In <FIG>, the flowchart <NUM> illustrates operations of a stylus according to an embodiment are described. At <NUM>, upon the tip of the stylus being brought proximate to the display of the computing device, the stylus transmits a signal including a stylus wireless protocol identifier of the stylus to the computing device via the communication channel not associated with the wireless protocol as described above (e.g., ES communication channel, NFC channel, etc.).

At <NUM>, the stylus receives a signal including a wireless protocol identifier of the computing device via the communication channel. The stylus may be configured to store the wireless protocol identifier of the computing device, such that the stylus and computing device are coupled as described herein.

At <NUM>, based on receiving user input indicating a signal associated with the received user input is to be sent to the coupled computing device using the wireless protocol, the stylus transmits the indicated signal to via the wireless protocol to the computing device using the wireless protocol identifier of the computing device. As described above, the transmitted signal may cause the computing device to perform an associated operation.

The system, as described herein, may further be configured to perform any of the following operations, in any combination:.

Various example scenarios are next described.

Miles gets his new uplink-enabled companion device and uplink-enabled pen device. Miles docks his pen to the uplink-enabled companion device. Miles is now able to enjoy his pen's full functionality, both inking and BLE, and pressing the tail button invokes actions on his Uplink-enabled companion device.

Miles also owns another uplink-enabled device. After inking with his new pen on his uplink-enabled companion device, Miles now starts writing on his second device, causing a loosely coupled connection to be formed between the pen and the second device, and the new pen is now fully functional on his second device, without the need for pairing or performing any actions. Miles can go back and forth between his uplink enabled devices, and every time the new pen is loosely coupled to the device that Miles is writing with his new pen.

Megan starts using her new pen on her legacy device. She would like to use the Bluetooth features on her legacy device, so Megan presses the button for <NUM> seconds. She is prompted to go through the pairing flow. She clicks and double clicks and finds the same responsiveness to the clicks that she experienced with her legacy pen and devices. It works great while the system is in connected standby, when the system is locked (above the lock screen) and when she is logged in. Once Megan either dock and/or starts inking with the new pen on her new uplink-enabled companion device, the new pen is now associated to the uplink-enabled companion device. If Megan wishes to use the BT features on her legacy device again, she would have to press the tail button for <NUM> seconds to initiate pairing.

George is using the new Hub device in the team's meeting room. After inking with the new pen, he can use the tail button to use its Bluetooth functionality. Daryl has joined George, and both are collaborating and inking on the device. Now Daryl's pen is also capable of sending Bluetooth messages. Matt walks in with his personal uplink-enabled companion device and uplink-enabled pen device. Matt inks on his Uplink-enabled companion device and the Hub device interchangeably. Matt's pen inks on both devices, and the tail button acts on the last device he had inked on.

In another example, upon activation from a locked state, sleep state, or the like, the host device caches the host BLE address in the digitizer of the host device. Later, upon locking the host device, the host BLE address may be cleared from the digitizer. While the host device is active, the digitizer may receive a pen ID (e.g., a <NUM>-bit ID) from a pen device when it is brought within a close proximity to the digitizer. In response, the digitizer may send the cached host BLE address to the pen device.

The host device may further receive a BLE address of the pen device from the pen device. The host device may map the received pen ID to the pen BLE address for later use. In order to facilitate secure communication, when unlocked, the host device may identify an authentication key (e.g., generate a new key or identify a key previously used with the pen device, etc.).

The authentication key is sent to the pen device after the pen device has received the host BLE address. The pen device and host device are loosely coupled.

Upon detecting a button press, the pen device initiates a BLE advertisement associated with the host device. The host device is already listening for the pen advertisement due to the loose coupling. The pen device sends a pen report that describes the pen event (e.g., the button press, etc.). The pen report is signed using the previously exchanged signing key and the key is sent with the pen report.

In some examples, a sign counter (e.g., a strictly increasing number with each message that is increased every time a new message is sent, etc.) is also used by the pen device and host device to prevent spoofing of pen reports. Both devices track the counter to predict the next valid number. This avoids replay attacks. Once the user stops using buttons of the pen, the connection between the host device and pen device may be disconnected. The loose coupling state may be maintained for a defined time period.

The present disclosure is operable with a computing apparatus according to an embodiment as a functional block diagram <NUM> in <FIG>. In an embodiment, components of a computing apparatus <NUM> may be implemented as a part of an electronic device according to one or more embodiments described in this specification. The computing apparatus <NUM> comprises one or more processors <NUM> which may be microprocessors, controllers or any other suitable type of processors for processing computer executable instructions to control the operation of the electronic device. Alternatively, or in addition, the processor <NUM> is any technology capable of executing logic or instructions, such as a hardcoded machine. Platform software comprising an operating system <NUM> or any other suitable platform software may be provided on the apparatus <NUM> to enable application software <NUM> to be executed on the device.

Computer executable instructions may be provided using any computer-readable media that are accessible by the computing apparatus <NUM>. Computer-readable media may include, for example, computer storage media such as a memory <NUM> and communications media. Computer storage media, such as a memory <NUM>, include volatile and non-volatile, removable and non-removable media implemented in any method or technology for storage of information such as computer readable instructions, data structures, program modules or the like. Computer storage media include, but are not limited to, RAM, ROM, EPROM, EEPROM, flash memory or other memory technology, CD-ROM, digital versatile disks (DVD) or other optical storage, magnetic cassettes, magnetic tape, magnetic disk storage or other magnetic storage devices, or any other non-transmission medium that can be used to store information for access by a computing apparatus. In contrast, communication media may embody computer readable instructions, data structures, program modules, or the like in a modulated data signal, such as a carrier wave, or other transport mechanism. As defined herein, computer storage media do not include communication media. Therefore, a computer storage medium should not be interpreted to be a propagating signal per se. Propagated signals per se are not examples of computer storage media. Although the computer storage medium (the memory <NUM>) is shown within the computing apparatus <NUM>, it will be appreciated by a person skilled in the art, that the storage may be distributed or located remotely and accessed via a network or other communication link (e.g. using a communication interface <NUM>).

The computing apparatus <NUM> may comprise an input/output controller <NUM> configured to output information to one or more output devices <NUM>, for example a display or a speaker, which may be separate from or integral to the electronic device. The input/output controller <NUM> may also be configured to receive and process an input from one or more input devices <NUM>, for example, a keyboard, a microphone or a touchpad. In one embodiment, the output device <NUM> may also act as the input device. An example of such a device may be a touch sensitive display. The input/output controller <NUM> may also output data to devices other than the output device, e.g. a locally connected printing device. In some embodiments, a user may provide input to the input device(s) <NUM> and/or receive output from the output device(s) <NUM>.

The functionality described herein can be performed, at least in part, by one or more hardware logic components. According to an embodiment, the computing apparatus <NUM> is configured by the program code when executed by the processor <NUM> to execute the embodiments of the operations and functionality described. For example, and without limitation, illustrative types of hardware logic components that can be used include Field-programmable Gate Arrays (FPGAs), Application-specific Integrated Circuits (ASICs), Program-specific Standard Products (ASSPs), SOC systems, Complex Programmable Logic Devices (CPLDs), GPUs.

At least a portion of the functionality of the various elements in the figures may be performed by other elements in the figures, or an entity (e.g., processor, web service, server, application program, computing device, etc.) not shown in the figures.

Examples of well-known computing systems, environments, and/or configurations that may be suitable for use with aspects of the disclosure include, but are not limited to, mobile or portable computing devices (e.g., smartphones), personal computers, server computers, hand-held (e.g., tablet) or laptop devices, multiprocessor systems, gaming consoles or controllers, microprocessor-based systems, set top boxes, programmable consumer electronics, mobile telephones, mobile computing and/or communication devices in wearable or accessory form factors (e.g., watches, glasses, headsets, or earphones), network PCs, minicomputers, mainframe computers, distributed computing environments that include any of the above systems or devices, and the like. In general, the disclosure is operable with any device with processing capability such that it can execute instructions such as those described herein. Such systems or devices may accept input from the user in any way, including from input devices such as a keyboard or pointing device, via gesture input, proximity input (such as by hovering), and/or via voice input.

While no personally identifiable information is tracked by aspects of the disclosure, examples have been described with reference to data monitored and/or collected from the users. In some examples, notice may be provided to the users of the collection of the data (e.g., via a dialog box or preference setting) and users are given the opportunity to give or deny consent for the monitoring and/or collection. The consent may take the form of opt-in consent or opt-out consent.

In some examples, the operations illustrated in the figures may be implemented as software instructions encoded on a computer readable medium, in hardware programmed or designed to perform the operations, or both. For example, aspects of the disclosure may be implemented as a system on a chip or other circuitry including a plurality of interconnected, electrically conductive elements.

Claim 1:
A system for coupling a stylus (<NUM>) to a computing device (<NUM>), the system comprising:
a computing device (<NUM>) having a display (<NUM>); the computing device configured to communicate with the stylus in accordance with a first wireless protocol and via at least one communication channel; the at least one communication channel being associated with a second wireless protocol, the computing device executing computer-executable instructions to:
receive a stylus wireless protocol identifier in a first signal from the stylus via the at least one communication channel upon a tip of the stylus being brought proximate to the display of the computing device;
based on receiving the stylus wireless protocol identifier, transmit a second signal including a wireless protocol identifier of the computing device and a signing key to the stylus via the at least one communication channel associated with the second wireless protocol, whereby the computing device is coupled to the stylus to listen for signals from the stylus; and
based on receiving a third signal from the coupled stylus to the computing device via the first wireless protocol, performing an operation on the computing device based on the third signal, the third signal indicating user input to the stylus; wherein the performing an operation based on the third signal includes launching an application on the computing device prior to an optional pairing of the coupled stylus to the computing device.