Pen and sensor controller

Abstract

The invention provides a pen and a sensor controller. The pen includes: a reception circuit configured to receive both a first uplink signal generated in accordance with a first protocol and a second uplink signal generated in accordance with a second protocol different from the first protocol; a control circuit configured to control an operation of the pen in at least two operation modes; and a transmission circuit configured to transmit a downlink signal, in which, when the reception circuit receives the second uplink signal, the control circuit enters a second operation mode in accordance with the second protocol, and when the reception circuit receives the second uplink signal, the control circuit enters a second operation mode in accordance with the second protocol. And whether the receiving circuit operating in the second operation mode receives the first uplink signal in accordance with the first protocol or the second uplink signal in accordance with the second protocol, the receiving circuit operating in the second operation mode receives the first uplink signal in accordance with the first protocol or the second uplink signal in accordance with the second protocol. The transmission circuit operating in the second operation mode transmits a second downlink signal in accordance with the second protocol.

Description

[0001] This application is a divisional application of an application with PCT application number PCT / JP2019 / 023168, international filing date of June 11, 2019, Chinese application number 201980096819.3, and invention title "Pen and Sensor Controller", which entered the Chinese national phase on November 25, 2021. Technical Field

[0002] The present invention relates to a pen and a sensor controller. Background Art

[0003] Regarding electronic devices such as electronic blackboards having a large-sized touch surface, in recent years, the use of simultaneously operating (drawing) multiple electronic pens has been increasing.

[0004] In Patent Document 1, an example of a sensor controller that enables simultaneous drawing with two electronic pens is disclosed. The sensor controller of this example assigns different local IDs to the two electronic pens for which detection has been completed, and is configured to be able to individually control each electronic pen by including the local ID in the command signal.

[0005] In Patent Document 2, an example of a sensor controller that establishes synchronization with an electronic pen when a pulse train of a specified length transmitted by the electronic pen is detected is disclosed.

[0006] Prior Art Documents

[0007] Patent Documents

[0008] Patent Document 1: International Publication No. 2018 / 043203 specification

[0009] Patent Document 2: U.S. Patent Publication No. 2015 / 0256329 specification Summary of the Invention

[0010] Problems to be Solved by the Invention

[0011] However, the protocol of the signals transmitted and received bidirectionally between the electronic pen and the sensor controller may change due to technological progress or the like. Thus, a situation may occur where some of two or more electronic pens simultaneously used in a certain electronic device correspond to a new protocol (hereinafter, referred to as the "new protocol"), while another part corresponds only to an old protocol (hereinafter, referred to as the "old protocol"). Therefore, in one electronic device, it is necessary to be able to use both an electronic pen corresponding to both the new and old protocols (hereinafter, referred to as the "new pen") and an electronic pen corresponding only to the old protocol (hereinafter, referred to as the "old pen").

[0012] Therefore, one object of the present invention is to provide an electronic pen and a sensor controller that can simultaneously use both new pens and old pens in one electronic device.

[0013] Technical solution for solving the problem

[0014] A pen according to one aspect of the present invention is configured to receive an uplink signal generated according to a first protocol and transmit a downlink signal according to the reception timing of the uplink signal and an instruction configured in the uplink signal. Wherein, when the pen receives the uplink signal and does not normally receive the next uplink signal during the period when the next uplink signal can be received but receives an uplink signal in a special state, according to the first protocol, it transmits the downlink signal including data or predetermined data according to the instruction configured in the first uplink signal received before this period.

[0015] A pen according to another aspect of the present invention is configured to be able to receive both a first uplink signal generated according to a first protocol and a second uplink signal generated according to a second protocol different from the first protocol. Wherein, after the pen enters a second operation mode according to the second protocol in response to receiving the second uplink signal, when it receives the first uplink signal, it transmits a second downlink signal according to the second protocol.

[0016] The sensor controller of the present invention is configured to be able to detect both a first downlink signal generated according to a first protocol and a second downlink signal generated according to a second protocol different from the first protocol. Wherein, the sensor controller is configured to alternately set a first frame for transmitting a first uplink signal for the first protocol and a second frame for transmitting a second uplink signal for the second protocol at a set ratio. In the second frame, the sensor controller detects both the first downlink signal and the second downlink signal.

[0017] Advantages of the invention

[0018] According to the present invention, both a new pen and an old pen can be used simultaneously in one electronic device. Description of the drawings

[0019] Figure 1 It is a diagram showing the whole of the position detection system 1 according to an embodiment of the present invention.

[0020] Figure 2 It is a diagram showing the arrangement of transmission (Tx) and reception (Rx) in the sensor controller 31.

[0021] Figure 3 It is a diagram showing the structure of the downlink signal DS.

[0022] Figure 4 It is a diagram showing the structure of the uplink signal US.

[0023] Figure 5 It is a diagram showing the internal structure of pen 2.

[0024] Figure 6 It is a diagram showing the internal structure of electronic device 3.

[0025] Figure 7 For (a), it is a diagram showing a structural example of uplink signal US1, and for (b) to (g), they are diagrams showing structural examples of uplink signal US2 respectively.

[0026] Figure 8 For (a), it is a diagram showing an example of an extended code constituting the preamble PRE used in the old protocol, and for (b), it is a diagram showing an example of an extended code constituting the preamble PRE used in the new protocol.

[0027] Figure 9 It is a mode transition diagram of the old pen, i.e., pen 2a.

[0028] Figure 10 It is a mode transition diagram of the new pen, i.e., pen 2b.

[0029] Figure 11 It is a mode transition diagram of sensor controller 31.

[0030] Figure 12 It is an explanatory diagram for explaining the mode transition of sensor controller 31.

[0031] Figure 13 It is an explanatory diagram for explaining the mode transition of sensor controller 31.

[0032] Figure 14 It is an explanatory diagram for explaining the steps of converting the communication of pen 2b paired with the old protocol to the new protocol.

[0033] Figure 15 It is a mode transition diagram of pen 2b according to the first modification of the embodiment of the present invention.

[0034] Figure 16 It is a diagram showing the arrangement of transmission (Tx) and reception (Rx) in sensor controller 31 according to the second modification of the embodiment of the present invention. Detailed Embodiment

[0035] Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings.

[0036] Figure 1It is a diagram showing the overall position detection system 1 of the present embodiment. As shown in this diagram, the position detection system 1 is configured to include two pens 2a, 2b and an electronic device 3. The electronic device 3 is configured to include a sensor electrode 30, a sensor controller 31, a panel 32, an electronic device control unit 33, and a liquid crystal display unit 34.

[0037] The pens 2a, 2b are both active styluses corresponding to the active electrostatic method and are used by one or more users simultaneously or separately. Hereinafter, when it is not necessary to particularly distinguish between the pens 2a, 2b, they are sometimes collectively referred to as pen 2.

[0038] The pen 2 and the sensor controller 31 are configured to be able to communicate in both directions. Hereinafter, as Figure 1 also shown, the signal sent from the sensor controller 31 to the pen 2 is called the uplink signal US, and the signal sent from the pen 2 to the sensor controller 31 is called the downlink signal DS.

[0039] The transceiver of the uplink signal US and the downlink signal DS is performed according to a prescribed protocol, but this protocol may be changed due to technological advancements, etc. Hereinafter, the protocol newly launched at a certain point in time is called the new protocol (second protocol), and the protocol used previously is called the old protocol (first protocol). In addition, it is assumed that pen 2a is an electronic pen (old pen) corresponding only to the old protocol and pen 2b is an electronic pen (new pen) corresponding to both the old and new protocols to continue the description.

[0040] An overview of the input operation of the pen 2 will be described. The user gradually brings the pen 2 closer to the surface (touch surface) of the panel 32 (putting the pen down. Recorded as "DOWN" in Figure 1 . Eventually, the tip of the pen 2 is brought into contact with the touch surface (pen touch). Then, when the user moves the tip on the touch surface while maintaining this contact state (pen movement), a moving trajectory is drawn on the touch surface through the processing of the electronic device 3. In Figure 1 , as an example of such a drawn trajectory, three trajectories st1 to st3 are shown. The drawing of the trajectory continues until the user lifts the tip of the pen 2a from the touch surface (lifting the pen. Recorded as "UP" in Figure 1 .

[0041] The pen 2 is configured to detect the uplink signal US supplied by the sensor controller 31 via the sensor electrode 30, and transmit a prescribed downlink signal DS based on the uplink signal US. As will be described in detail later, the sensor controller 31 obtains the position of the pen 2 within the touch surface and the data transmitted by the pen 2 by receiving the downlink signal DS via the sensor electrode 30. The position and data obtained by the sensor controller 31 are sequentially supplied to the electronic device control unit 33. The electronic device control unit 33 generates stroke data based on the position and data thus supplied, and outputs the stroke data to the liquid crystal display unit 34 on the basis of drawing, thereby depicting the above-described trajectory on the touch surface.

[0042] Figure 2 FIG. is a diagram showing the arrangement of transmission (Tx) and reception (Rx) in the sensor controller 31. As shown in this figure, the sensor controller 31 is configured to transmit the uplink signal US and receive the downlink signal DS in units of frames F. Within each frame F, the transmission of the uplink signal US and the reception of the downlink signal DS are performed in a time-division manner. Specifically, first, at the beginning of each frame F, the sensor controller 31 transmits the uplink signal US. Then, during the remaining time of each frame F, the pen 2 transmits the downlink signal DS.

[0043] Here, as can be observed Figure 2 As understood, in the present embodiment, two reception time slots TS1 and TS2 are provided in one frame F. Hereinafter, when it is not necessary to particularly distinguish between the time slots TS1 and TS2, they are sometimes collectively referred to as the time slot TS. These time slots TS are set so that different pens 2 can transmit the downlink signal DS in a time-division manner. In the present embodiment, two time slots TS1 and TS2 are provided, whereby within one frame F, at most two pens 2 can transmit the downlink signal DS. This means that the maximum number of pens 2 that can be paired with the sensor controller 31 simultaneously is two. However, as exemplified later in Figure 16 As exemplified, the maximum number of pens 2 that can be paired with the sensor controller 31 simultaneously is not limited to two. The time slot TS used by each pen 2 is determined when the sensor controller 31 and the pen 2 are paired.

[0044] Figure 3 FIG. is a diagram showing the structure of the downlink signal DS. (a) of this figure shows the downlink signal DS transmitted by the pen 2 that has not detected the sensor controller 31, and (b) of this figure shows the downlink signal DS transmitted by the pen 2 paired with the sensor controller 31.

[0045] As Figure 3As shown in (a) of [Figure 0], for the pen 2 where the sensor controller 31 has not been detected, only the position signal PS is sent as the downlink signal DS. The position signal PS is, for example, an unmodulated carrier signal. In this case, the position signal PS is used by the sensor controller 31 to detect the position of the pen 2 across the entire touch surface. In this specification, this position detection is referred to as "global scanning". The specific method for position detection based on global scanning will be described later.

[0046] On the other hand, as shown in Figure 3 (b) of [Figure 0], for the pen 2 paired with the sensor controller 31, in addition to the above-mentioned position signal PS, a data signal DATA is also sent as the downlink signal DS. In this case, the position signal PS is used by the sensor controller 31 to update the position of the pen 2. In this specification, this position update is referred to as "local scanning". The specific method for position update based on local scanning will be described later.

[0047] The data signal DATA is a signal for sending the data held in the pen 2 to the sensor controller 31, and is configured to include the pen pressure value detected by a pen pressure detection unit 23 (refer to Figure 5 ), the on / off value of a switch provided on the side or bottom surface of the housing of the pen 2, and the pen ID for uniquely identifying each pen 2, etc. The pen 2 usually sends a downlink signal DS in which only the pen pressure value is configured in the data signal DATA. On the other hand, in the case where the sensor controller 31 instructs the transmission of specific data through an instruction COMDATA described later, the pen 2 sends a downlink signal DS including the data according to the instruction COMDATA.

[0048] Here, Figure 3 the bit A shown in (b) of [Figure 0] is flag information that has different values in the case where the pen 2 corresponds only to the old protocol and in the case where the pen 2 corresponds to both the old protocol and the new protocol, and is used to notify the sensor controller 31 of the correspondence status with the new protocol. The bit A only needs to be included in the downlink signal DS generated according to the old protocol, and may not be included in the downlink signal DS generated according to the new protocol.

[0049] Figure 4 [Figure 19] is a diagram showing the structure of the uplink signal US. As shown in this figure, the uplink signal US is configured to include a preamble PRE, an instruction signal COM, and an error detection code CRC.

[0050] The preamble PRE is a synchronization signal known to the pen 2 used to synchronize the pen 2 with the sensor controller 31. This synchronization signal is composed of a prescribed spreading code (pulse train) composed of chips with a chip width of a prescribed length (e.g., 0.5 us, 1.0 us, 2.0 us,...). The chip length of this spreading code (the chip period of the spreading code) is, for example, 7, 15, 31, 63 [chips].... Additionally, a synchronization signal can also be formed by connecting two or more spreading codes with such chip lengths. As another example, the synchronization signal can also be, for example, a pulse train of a specific frequency with a pulse width of the length as in the above examples for a prescribed number of consecutive pulses. The pen 2 continuously or intermittently performs a detection operation of the spreading code that constitutes the preamble PRE. When the preamble PRE is detected, the presence of the sensor controller 31 is detected, and synchronization with the sensor controller 31 is achieved according to the timing of detecting the preamble PRE. The synchronization mentioned here means determining the transmission timing of the downlink signal DS and the reception timing of the next uplink signal US (i.e., the transceiver arrangement of the uplink signal US and the downlink signal DS) according to the timing of detecting the preamble PRE. The pen 2 is configured to update this synchronization each time it receives the uplink signal US.

[0051] The command signal COM is configured to include the local ID (LID) of the pen 2 indicating the destination of the command signal COM, the command COMDATA including a command for the pen 2, and each represented by 1 bit Figure 2 the slot status information STA indicating the idle status of each of the shown time slots TS1, TS2.

[0052] The error detection code CRC is a code obtained by performing a prescribed operation with the command signal COM as the input, and is used to detect errors that occur during the transmission of the command signal COM.

[0053] The pen 2 that receives the uplink signal US in a state where the sensor controller 31 has not been detected confirms the idle status of the time slots TS1, TS2 by referring to the slot status information STA. As a result, when a certain time slot TS is empty, the pen 2 uses this time slot TS to send a downlink signal DS containing only the position signal PS. The sensor controller 31 that receives this downlink signal DS changes the slot status information STA of the time slot TS of the received downlink signal DS to in use in the subsequently transmitted uplink signal US. The pen 2 that receives this uplink signal US detects that it has been detected by the sensor controller 31 by detecting the change in the slot status information STA, and obtains a prescribed local ID corresponding to the time slot TS that transmitted the downlink signal DS (e.g., 0 if it is time slot TS1, 1 if it is time slot TS, etc.), and stores it in its own memory.

[0054] When the pen 2 storing the local ID receives and decodes the uplink signal US later, it first refers to the local ID in the instruction signal COM to determine whether it is the same as the local ID stored in its own memory 45, thereby determining whether the uplink signal US is sent to itself. As a result of this determination, in the case of the uplink signal US determined to be sent to itself, the pen 2 extracts the instruction COMDATA from the instruction signal COM and performs processing corresponding to its content. In this processing, it includes the processing of obtaining the data requested to be sent from the sensor controller 31 and configuring the data in the subsequent downlink signal DS. On the other hand, in the case of the uplink signal US determined not to be sent to itself, the pen 2 does not obtain the instruction COMDATA in the instruction signal COM, but sends a predetermined downlink signal DS including the position signal PS and the data signal DATA containing only the pen pressure value.

[0055] The sensor controller 31 is configured to detect the presence and position of the pen 2 by receiving the position signal PS using the sensor electrode 30. Figure 1 The indicated positions P1, P2 shown are examples of such detected positions. The above trajectories st1 to st3 are the trajectories of the movement of the indicated positions P1, P2. The sensor controller 31 is also configured to obtain the data (such as pen pressure value) sent by the pen 2 by receiving the data signal DATA using the sensor electrode 30.

[0056] Figure 5 It is a diagram showing the internal structure of the pen 2. As shown in this diagram, the pen 2 is configured to have a core body 20, a nib electrode 22, a pen pressure detection unit 23, a power source 26, and an integrated circuit 27.

[0057] The core body 20 is a rod-shaped member whose longitudinal direction is arranged in the same direction as the pen axis of the pen 2, and one end thereof constitutes the nib end 21 of the pen 2. A conductive material is coated on the surface of the core body 20 to form the nib electrode 22.

[0058] The nib electrode 22 is a conductor provided near the core body 20 and is electrically connected to the integrated circuit 27 through wiring. The integrated circuit 27 receives the uplink signal US and transmits the downlink signal DS via the nib electrode 22. However, the nib electrode 22 can also be separated into an electrode for transmission and an electrode for reception.

[0059] The pen pressure detection unit 23 is a functional unit that detects the force (pen pressure value) applied to the nib end 21. Specifically, the pen pressure detection unit 23 is configured to abut against the rear end portion of the core body 20, and through this abutment, detect the force applied to the nib end 21 when the user presses the nib of the pen 2 against a touch surface or the like. In a typical example, the pen pressure detection unit 23 is composed of a variable capacitance module whose electrostatic capacitance changes according to the force applied to the nib end 21.

[0060] The power supply 26 is used to supply operating power (DC voltage) to the integrated circuit 27 and is constituted by, for example, a cylindrical AAAA battery.

[0061] The integrated circuit 27 is a processing unit constituted by a circuit group formed on a substrate (not shown), and performs processing of receiving the uplink signal US via the nib electrode 22, generating a downlink signal DS based on the received uplink signal US, and transmitting the downlink signal DS via the nib electrode 22. The type of protocol corresponding to the pen 2 (only the old protocol or both the old and new protocols) is determined by at least one of the firmware and hardware of the integrated circuit 27.

[0062] For detailed content, refer to Figure 9 As described later, the integrated circuit 27 of the old pen 2a corresponding only to the old protocol is configured to operate in one of a discovery mode S0 for discovering the sensor controller 31, a communication mode S1 for communicating with the discovered sensor controller 31, and a continue mode S1a for continuing to communicate with the sensor controller 31 even when an uplink signal US in a special state described later is received after entering the communication mode S1. Hereinafter, the uplink signal US in the special state will be referred to as "uplink signal SUS", and the uplink signal US normally received according to the old protocol will be referred to as "uplink signal NUS".

[0063] On the other hand, for detailed content, refer to Figure 10 As described later, the integrated circuit 27 of the new pen 2b corresponding to both the old and new protocols is configured to operate in one of a discovery mode S10 for discovering the sensor controller 31, an old mode S11 (first operation mode) for communicating with the discovered sensor controller 31 based on the old protocol, an old continue mode S11a for continuing to communicate with the sensor controller 31 even when an uplink signal US generated according to the new protocol is received after entering the old mode S11, a new mode S12 (second operation mode) for communicating with the discovered sensor controller 31 based on the new protocol, and a new continue mode S12a for continuing to communicate with the sensor controller 31 even when an uplink signal US generated according to the old protocol is received after entering the new mode S12. Hereinafter, the uplink signal US generated according to the old protocol will be referred to as "uplink signal US1", and the uplink signal US generated according to the new protocol will be referred to as "uplink signal US2". For the pen 2a, the uplink signal US1 is the uplink signal NUS, and the uplink signal US2 is the uplink signal SUS.

[0064] Next, Figure 6 is a diagram showing the internal structure of the electronic device 3. Hereinafter, with reference to this Figure 6, the structure and operation of the electronic device 3 will be described in detail.

[0065] The sensor electrode 30 is composed of a plurality of linear electrodes 30X extending in the Y direction and a plurality of linear electrodes 30Y extending in the X direction respectively. The sensor electrode 30 is configured such that the pen 2 is capacitively coupled to these linear electrodes 30X and 30Y. The above-mentioned uplink signal US and downlink signal DS are transmitted and received via this capacitive coupling.

[0066] As Figure 6 shown, the sensor controller 31 is configured to include an MCU 60, a logic unit 61, a transmission unit 62, a reception unit 63, and a selection unit 64.

[0067] The MCU 60 and the logic unit 61 are control units that control the transmission and reception operations of the sensor controller 31 by controlling the transmission unit 62, the reception unit 63, and the selection unit 64. Specifically, the MCU 60 is a microprocessor having a ROM and a RAM inside and operating based on a prescribed program. Among the processes performed by the MCU 60, in addition to the process of controlling the logic unit 61, it also includes a process of generating an instruction signal COM and an error detection code CRC according to the control of the electronic device control unit 33 and supplying them to the transmission unit 62, and a process of deriving the coordinates x and y of the pen 2 from the downlink signal DS supplied from the reception unit 63, receiving the data Res transmitted by the pen 2, and outputting it together with the local ID of the pen 2 to the electronic device control unit 33. On the other hand, the logic unit 61 is configured to output control signals ctrl_t1 to ctrl_t4 and ctrl_r based on the control of the MCU 60.

[0068] The MCU 60 is configured to transmit the uplink signal US and receive the downlink signal DS according to the Figure 2 transmission and reception arrangement shown. Specifically, referring to Figure 11 which will be described later, the MCU 60 has three modes, namely the new-old hybrid mode, the old-only mode, and the new-only mode, as the transmission mode of the uplink signal US. When entering the new-old hybrid mode, the MCU 60 is configured to alternately set the frame F (the first frame) of the uplink signal US1 for the old protocol and the frame F (the second frame) of the uplink signal US2 for the new protocol at a set ratio (for example, 1:1). On the other hand, when entering the old-only mode, the MCU 60 is configured to transmit the uplink signal US1 for the old protocol in all frames F. In addition, when entering the new-only mode, the MCU 60 is configured to transmit the uplink signal US2 for the new protocol in all frames F.

[0069] In addition, for detailed content, also refer to Figure 11As described later, the MCU 60 has three modes, i.e., a discovery mode, an old mode, and a new mode, as the reception modes of the downlink signal DS for each time slot TS. In the time slot TS that enters the discovery mode, the MCU 60 waits to receive the downlink signal DS transmitted by the unpaired pen 2. In addition, in the time slot TS that enters the old mode, the MCU 60 waits to receive the downlink signal DS generated by the pen 2 according to the old protocol. On the other hand, in the time slot TS that enters the new mode, the MCU 60 waits to receive the downlink signal DS generated by the pen 2 according to the new protocol. Hereinafter, the downlink signal DS generated according to the old protocol is referred to as "downlink signal DS1", and the downlink signal DS generated according to the new protocol is referred to as "downlink signal DS2".

[0070] Here, the reception mode of the downlink signal DS is set regardless of the transmission mode of the uplink signal US. Therefore, the MCU 60 sometimes detects both the downlink signals DS1 and DS2 in the frame F in which the uplink signal US1 is transmitted, and sometimes also detects both the downlink signals DS1 and DS2 in the frame F in which the uplink signal US2 is transmitted.

[0071] Figure 7 Fig. (a) is a diagram showing a structural example of the uplink signal US1. Figure 7 Figs. (b) to (g) are diagrams showing structural examples of the uplink signal US2, respectively. Both the uplink signals US1 and US2 have the structure shown in Figure 4 and have a common part in some parts, but there are differences due to different protocols. The content of this difference is not particularly limited, and various methods can be considered. Figs. (b) to (g) in Figure 7 show six of such methods. Hereinafter, each will be described in detail.

[0072] Figure 7 Fig. (b) is an example in which the value of the bit B that is defined as the first value (e.g., "0") in the old protocol is set to the second value (e.g., "1") different from the first value in the new protocol. In this case, after decoding the received uplink signal US, the new pen, i.e., the pen 2b, can determine which of the uplink signals US1 and US2 the uplink signal US is by referring to the value of the bit B. On the other hand, after decoding the received uplink signal US, the old pen, i.e., the pen 2a, determines that it can receive normally if the bit B is the first value, and determines that an abnormality is detected in the decoding of the instruction if the bit B is the second value. Moreover, in the former case, it is determined that the received uplink signal US is the above-mentioned uplink signal NUS, and in the latter case, it is determined that the received uplink signal US is the uplink signal SUS in the above-mentioned special state.

[0073] In addition, it is possible to useFigure 7 In the case of the uplink signal US2 in (b), for example, there is a reserved field within the uplink signal US1. The value of the reserved field does not have a specific meaning, but usually has a specific value (e.g., "0"). When the old protocol was designed, it was impossible to specifically foresee how bits would be allocated in the field in the new protocol. However, by setting a value different from the above specific value (e.g., "1") in the above field during the design of the new protocol, when pen 2a receives the uplink signal US1, it can recognize that a value other than the normal value is set in the above field. Therefore, the received uplink signal US can be determined to be an uplink signal SUS in a special state.

[0074] Figure 7 In (c), an example is shown where, in the new protocol, instead of the error detection code CRC obtained by performing a specified operation with the instruction signal COM as input, an inverted error detection code RCRC obtained by inverting the error detection code CRC is configured within the uplink signal US. In this case, the new pen, namely pen 2b, extracts the part corresponding to the error detection code CRC or the inverted error detection code RCRC from the received uplink signal US, attempts error detection without inverting this part, and attempts error detection after inverting this part. Thus, it can be determined which of the uplink signals US1 and US2 the uplink signal US is. That is, when the result of error detection after inverting the extracted part shows no error detected, pen 2b can determine that the uplink signal US2 has been received. When the result of error detection without inverting the extracted part shows no error detected, pen 2b can determine that the uplink signal US1 has been received. On the other hand, in the old pen, namely pen 2a, if the error detection code CRC is configured within the received uplink signal US, the decoding result becomes a code word (i.e., no error is detected by the error detection code). However, if the inverted error detection code RCRC is configured, the decoding result does not become a code word (i.e., an error is detected by the error detection code). Therefore, when the decoding result becomes a code word or when it does not become a code word and the CRC field contains an inverted value, pen 2a determines that the received uplink signal US is the above uplink signal NUS. When the decoding result does not become a code word, pen 2a determines that the received uplink signal US is the above uplink signal SUS in a special state. In this way, as Figure 7 shown in (b), without using a new field, by utilizing the CRC field existing in the old protocol, it is possible to represent the issuance of an instruction suitable for the new protocol.

[0075] Figure 7 In (d), an example is shown where the preamble PRE of the new protocol is longer than the preamble PRE of the old protocol. Figure 7 In (e), an example is shown where, different from the old protocol, no error detection code CRC is set in the new protocol.Figure 7 In (f), an example is shown where the time length of the command signal COM of the new protocol is made shorter than that of the command signal COM of the old protocol through multi-valued conversion or the like. Figure 7 In (g), different from the old protocol, no error detection code CRC is set in the new protocol, and through multi-valued conversion or the like, the time length of the command signal COM of the new protocol is made shorter than that of the command signal COM of the old protocol. In either case, the new pen, i.e., pen 2b, can attempt to decode by assuming that the received uplink signal US is each of the uplink signals US1 and US2, and thereby determine which of the uplink signals US1 and US2 the uplink signal US is. On the other hand, the old pen, i.e., pen 2a, decodes the uplink signal US only as the uplink signal US1. Therefore, when the uplink signal US is the uplink signal US2, an abnormal result will be obtained. Thus, when pen 2a obtains a normal decoding result, it determines that the received uplink signal US is the above-mentioned uplink signal NUS, and when it obtains an abnormal decoding result, it determines that the received uplink signal US is the uplink signal SUS in the above-mentioned special state.

[0076] In addition, as in Figure 7 the example shown in (d), when different preambles PRE are used in the old protocol and the new protocol, each preamble PRE can also be configured in such a way that the chip width of the spreading code (the time length per chip, i.e., the fundamental frequency or an integer multiple frequency of the chip (pulse)), a part of the code (chip string) constituting the spreading code, is consistent (including the case where the result of the correlation operation is equal to or greater than a specified value), or only a part such as the beginning part of the preamble PRE composed of patterns of multiple spreading codes is consistent. In this case, the old pen, i.e., pen 2a, can also determine that the received uplink signal US is the uplink signal SUS in the above-mentioned special state when it detects the consistency of this part in addition to obtaining an abnormal decoding result. In this way, it is possible to prevent the uplink signal SUS in the special state from being determined in the case of decoding errors caused by noise or the like.

[0077] Figure 8 (a) shows an example of the spreading code constituting the preamble PRE used in the old protocol. Figure 8The (b) shows an example of the spreading code that constitutes the preamble PRE used in the new protocol. In these examples, different preambles PRE are used in the old protocol and the new protocol, but the chip width L of the spreading code is the same. If the preamble PRE like this example is used, the old pen, that is, pen 2a, will get abnormal decoding results (including results where all of the preamble PRE (or uplink signal US) is inconsistent). As long as the chip width L is detected to be the same, it can be determined that the received uplink signal US is the above-mentioned special state uplink signal SUS. Instead of the chip width L being the same, or in addition to the chip width L being the same, it is the same when a partial consistency of the code constituting the spreading code or the preamble PRE is detected.

[0078] Return to Figure 6 . The transmitting unit 62 is a circuit that generates the uplink signal US according to the control of the MCU 60 and the logic unit 61. As Figure 6 shown, it is configured to include a pattern supply unit 80, a switch 81, a code string holding unit 82, a spreading processing unit 83, and a transmission protection unit 84. In addition, especially regarding the pattern supply unit 80, in this embodiment, it is described as being included in the transmitting unit 62, but it can also be included in the MCU 60.

[0079] The pattern supply unit 80 is a functional unit that outputs the symbols constituting the preamble PRE according to the instruction of the control signal ctrl_t1 supplied from the logic unit 61. The symbols constituting the preamble PRE are composed of preamble-specific symbols that do not correspond to any one of, for example, 0 to 15.

[0080] The switch 81 functions as follows. According to the control signal ctrl_t2 supplied from the logic unit 61, it selects either the pattern supply unit 80 or the MCU 60, and supplies the output of the selected one to the spreading processing unit 83. When the switch 81 selects the pattern supply unit 80, the symbols constituting the preamble PRE are supplied from the pattern supply unit 80 to the spreading processing unit 83. On the other hand, when the switch 81 selects the MCU 60, the instruction signal COM and the error detection code CRC are supplied from the MCU 60 to the spreading processing unit 83. The instruction signal COM and the error detection code CRC supplied to the spreading processing unit 83 are each composed of a string of symbols corresponding to, for example, a certain one of 0 to 15.

[0081] The code string holding unit 82 has the function of generating and holding a spreading code PN with a specified chip length having autocorrelation characteristics according to the control signal ctrl_t3 supplied from the logic unit 61. In the code string holding unit 82, different spreading codes PN are held according to the type of symbol. The spreading code PN held by the code string holding unit 82 is supplied to the spreading processing unit 83.

[0082] The expansion processing unit 83 has the following function: it expands the value of the symbol (preamble PRE or instruction signal COM) supplied via the switch 81 by the corresponding spreading code among the multiple spreading codes PN held in the code string holding unit 82, thereby obtaining a transmission chip string. The expansion processing unit 83 is configured to supply the obtained transmission chip string to the transmission protection unit 84.

[0083] The transmission protection unit 84 has the following function: according to the control signal ctrl_t4 supplied from the logic unit 61, during the transmission period of the uplink signal US and the reception period of the downlink signal DS, it inserts a protection period (a period during which neither transmission nor reception is performed) required for switching the transmission operation and the reception operation.

[0084] The receiving unit 63 is a circuit for receiving the downlink signal DS transmitted by the pen 2 according to the control signal ctrl_r supplied from the logic unit 61. Specifically, it is configured to include an amplifier circuit 85, a detection circuit 86, and an analog-to-digital (AD) converter 87.

[0085] The amplifier circuit 85 amplifies the downlink signal DS supplied from the selection unit 64 and outputs it. The detection circuit 86 is a circuit that generates a voltage corresponding to the level of the output signal of the amplifier circuit 85. The AD converter 87 is a circuit that generates a digital signal by sampling the voltage output from the detection circuit 86 at a prescribed time interval. The digital signal output by the AD converter 87 is supplied to the MCU 60. The MCU 60 obtains the data Res (pen pressure value, pen ID, etc.) transmitted by the pen 2 according to the digital signal thus supplied.

[0086] The selection unit 64 is configured to include switches 88x, 88y, and conductor selection circuits 89x, 89y.

[0087] The switches 88x, 88y are switch elements each configured such that a common terminal is connected to either the T terminal or the R terminal of a 1-circuit 2-contact. The common terminal of the switch 88x is connected to the conductor selection circuit 89x, the T terminal is connected to the output terminal of the transmission unit 62, and the R terminal is connected to the input terminal of the receiving unit 63. Additionally, the common terminal of the switch 88y is connected to the conductor selection circuit 89y, the T terminal is connected to the output terminal of the transmission unit 62, and the R terminal is connected to the input terminal of the receiving unit 63.

[0088] The conductor selection circuit 89x is a switch element for selectively connecting multiple linear electrodes 30X to the common terminal of the switch 88x. The conductor selection circuit 89x is configured to be able to connect a part or all of the multiple linear electrodes 30X to the common terminal of the switch 88x simultaneously.

[0089] The conductor selection circuit 89y is a switching element for selectively connecting a plurality of linear electrodes 30Y to the common terminal of the switch 88y. The conductor selection circuit 89y is also configured to be able to connect a part or all of the plurality of linear electrodes 30Y to the common terminal of the switch 88y simultaneously.

[0090] Four control signals sTRx, sTRy, selX, and selY are supplied from the logic unit 61 to the selection unit 64. Specifically, the control signal sTRx is supplied to the switch 88x, the control signal sTRy is supplied to the switch 88y, the control signal selX is supplied to the conductor selection circuit 89x, and the control signal selY is supplied to the conductor selection circuit 89y. The logic unit 61 controls the selection unit 64 by using these control signals sTRx, sTRy, selX, and selY to realize the transmission of the uplink signal US and the reception of the downlink signal DS.

[0091] More specifically, when transmitting the uplink signal US, the logic unit 61 controls the selection unit 64 so that all of the plurality of linear electrodes 30Y (or all of the plurality of linear electrodes 30X) are connected to the output terminal of the transmission unit 62.

[0092] The operation of the logic unit 61 when receiving the position signal PS included in the downlink signal DS is different depending on whether it is paired with the pen 2 in the time slot TS when the position signal PS is received. In the time slot TS when not paired, the logic unit 61 controls the selection unit 64 so that all of the plurality of linear electrodes 30X and 30Y are sequentially connected to the input terminal of the reception unit 63 during the duration of the time slot TS. In this way, the MCU 60 can obtain the reception intensity of the position signal PS of each of all the linear electrodes 30X and 30Y, and thus can detect the position of the pen 2 over the entire touch surface (global scan). On the other hand, in the time slot TS when not paired, the logic unit 61 controls the selection unit 64 so that a predetermined number of linear electrodes 30X and 30Y located near the previously detected position are sequentially connected to the input terminal of the reception unit 63 during the transmission duration of the position signal PS. In this way, the MCU 60 can obtain the reception intensity of the position signal PS of a predetermined number of linear electrodes 30X and 30Y located near the previously detected position, and thus can update the position of the pen 2 (local scan).

[0093] When receiving the data signal DATA included in the downlink signal DS, the logic unit 61 controls the selection unit 64 so that only one electrode closest to the position derived from the previous position signal PS of the pen 2 that transmitted the data signal DATA among the plurality of linear electrodes 30X and 30Y is connected to the input terminal of the reception unit 63. Thereby, the transmission time of the data signal DATA can be fully utilized for transmitting data from the pen 2 to the sensor controller 31.

[0094] As described above, the structures of the pen 2 and the electronic device 3 that constitute the position detection system 1 have been described, and the uplink signal US and the downlink signal DS have been described. Next, the operations of the pen 2 and the electronic device 3 will be described in detail with reference to the respective mode transition diagrams.

[0095] Figure 9 This is the mode transition diagram of the old pen, namely the pen 2a. As shown in this figure, the pen 2a is configured to operate in one of the discovery mode S0, the communication mode S1, and the continuation mode S1a.

[0096] The discovery mode S0 is a mode for discovering the sensor controller 31. The pen 2a that enters the discovery mode S0 intermittently or continuously performs the detection operation of the uplink signal US. Moreover, when the uplink signal NUS is received, the transceiver arrangement of the uplink signal US and the downlink signal DS is determined according to the reception timing, and the pen 2a transfers to the communication mode S1. On the other hand, when the uplink signal SUS is received, the pen 2a stays in the discovery mode S0 and attempts to receive the next uplink signal US.

[0097] The pen 2a that enters the communication mode S1 communicates with the sensor controller 31 while staying in the communication mode S1 during the period of receiving the uplink signal NUS according to the transceiver arrangement. Specifically, the transceiver arrangement is updated according to the reception timing of the received uplink signal NUS, and the downlink signal DS is transmitted according to the updated transceiver arrangement. The downlink signal DS thus transmitted is a signal generated by the pen 2a according to the old protocol, and includes data indicated by an instruction COMDATA in the previous uplink signal NUS or predetermined data such as a pen pressure value.

[0098] On the other hand, when the pen 2a does not receive the uplink signal US according to the transceiver arrangement, it is determined that the pen 2a has left the sensor controller 31, and the pen 2a returns to the discovery mode S0. In addition, when the uplink signal SUS is received without normally receiving the next uplink signal NUS during the transceiver arrangement (that is, during the period when the next uplink signal NUS can be received), the pen 2a transfers to the continuation mode S1a.

[0099] The pen 2a that enters the continuation mode S1a updates the transceiver arrangement according to the reception timing of the uplink signal SUS when the uplink signal SUS is received, and transmits the downlink signal DS according to the old protocol. Specifically, the downlink signal DS including data configured by an instruction in the uplink signal NUS received before the above period or predetermined data such as a pen pressure value is transmitted.

[0100] On the other hand, when the pen 2a receives the uplink signal NUS, it returns to the communication mode S1. Additionally, in the case where the uplink signal SUS is detected continuously more than n times (n is any natural number of 2 or more, i.e., the uplink signal NUS is not detected), and in the case where the uplink signal US is not received according to the transceiver arrangement, it returns to the discovery mode S0.

[0101] Figure 10 It is a mode transition diagram of a new pen, namely the pen 2b. As shown in this diagram, the pen 2b is configured to operate in one of the discovery mode S10, the old mode S11, the old continuation mode S11a, the new mode S12, and the new continuation mode S12a.

[0102] The discovery mode S10 is the same as the discovery mode S0 of the pen 2a shown in Figure 9 and is a mode for discovering the sensor controller 31. The pen 2b in the discovery mode S10 intermittently or continuously performs the detection operation of the uplink signal US. Moreover, when the uplink signal US1 is received, the transceiver arrangement of the uplink signal US and the downlink signal DS is determined according to the reception timing, and it transfers to the old mode S11. On the other hand, when the uplink signal US2 is received, the transceiver arrangement of the uplink signal US and the downlink signal DS is determined according to the reception timing, and it transfers to the new mode S12.

[0103] The pen 2b that enters the old mode S11 stays in the old mode S11 and communicates with the sensor controller 31 during the period when the uplink signal US1 is received according to the transceiver arrangement. Specifically, the transceiver arrangement is updated according to the reception timing of the received uplink signal US (including the uplink signals US1 and US2), and the downlink signal DS is transmitted according to the updated transceiver arrangement. The downlink signal DS thus transmitted is a signal generated by the pen 2b according to the old protocol and includes established data such as the data indicated by the instruction COMDATA in the previous uplink signal US1 or the pen pressure value.

[0104] On the other hand, when the pen 2b does not receive the uplink signal US according to the transceiver arrangement, it determines that it has left the sensor controller 31 and returns to the discovery mode S10. Additionally, when the uplink signal US2 is received according to the transceiver arrangement, it transfers to the old continuation mode S11a.

[0105] When the pen 2b that has entered the old continuation mode S11a receives the uplink signal US2, it updates the transceiver arrangement according to the reception timing of the uplink signal US2 and transmits the downlink signal DS according to the old protocol. Specifically, it transmits a downlink signal DS that contains data according to the instructions configured in the previously received uplink signal US1, or established data such as pen pressure values.

[0106] On the other hand, when the pen 2b receives the uplink signal US1, it returns to the old mode S11. Additionally, when the uplink signal US2 is detected continuously more than n times (n is any natural number greater than or equal to 2, i.e., the uplink signal US1 is not detected), and when the uplink signal US is not received according to the transceiver arrangement, it returns to the discovery mode S10.

[0107] Here, when the instruction COMDATA configured in the received uplink signal US1 is a conversion instruction indicating mode conversion, as Figure 10 shown by the dashed line in the figure, it preferably transfers to the new mode S12. Thus, through the indication from the sensor controller 31, the mode of the pen 2b can be forcibly switched to the new mode S12.

[0108] Next, while the pen 2b that has entered the new mode S12 is receiving the uplink signal US2 according to the transceiver arrangement, it stays in the new mode S12 and communicates with the sensor controller 31. Specifically, it updates the transceiver arrangement according to the reception timing of the received uplink signal US (including uplink signals US1 and US2), and transmits the downlink signal DS according to the updated transceiver arrangement. The downlink signal DS thus transmitted is a signal generated by the pen 2b according to the new protocol, and contains data indicated by the instruction COMDATA in the previous uplink signal US2, or established data such as pen pressure values.

[0109] On the other hand, when the pen 2b does not receive the uplink signal US according to the transceiver arrangement, it determines that it has left the sensor controller 31 and returns to the discovery mode S10. Additionally, when the uplink signal US1 is received according to the transceiver arrangement, it transfers to the new continuation mode S12a.

[0110] When the pen 2b that has entered the new continuation mode S12a receives the uplink signal US1, it updates the transceiver arrangement according to the reception timing of the uplink signal US1 and transmits the downlink signal DS according to the new protocol. Specifically, it transmits a downlink signal DS that contains data according to the instructions configured in the previously received uplink signal US2, or established data such as pen pressure values.

[0111] On the other hand, when the pen 2b receives the uplink signal US2, it returns to the new mode S12. Additionally, when the uplink signal US1 is detected continuously more than n times (n is any natural number greater than or equal to 2, i.e., the uplink signal US2 is not detected) and when the uplink signal US is not received according to the transceiver arrangement, it returns to the discovery mode S10.

[0112] Figure 11 is the mode transition diagram of the sensor controller 31. As shown in this figure, the sensor controller 31 has a reception mode for the downlink signal DS for each time slot TS and a transmission mode for the uplink signal US. The former includes the discovery mode, the old mode, and the new mode, and the latter includes the old and new hybrid mode, the old-only mode, and the new-only mode. Additionally, Figure 12 and Figure 13 are explanatory diagrams for explaining the mode transition of the sensor controller 31. Hereinafter, with reference to these Figures 11 - 13 the mode transition of the sensor controller 31 will be described.

[0113] First, Figure 11 The state S20 shown is the initial state where the sensor controller 31 is not paired with any pen 2. In this state S20, the reception mode for each of the two time slots TS1 and TS2 is the discovery mode, and the transmission mode for the uplink signal US is the old and new hybrid mode. In this case, the sensor controller 31 alternately sets the frame F for transmitting the uplink signal US1 for the old protocol and the frame F for transmitting the uplink signal US2 for the new protocol at a set ratio. This ratio is preferably 1:1, but it can also be other than 1:1.

[0114] Figure 12 Figure (a) of shows the case where the sensor controller 31 receives the downlink signal DS2 in the time slot TS1 within the frame F of the uplink signal US2 when in the state S20. The pen 2 that sends the initial downlink signal DS2 according to the uplink signal US2 is the pen 2b. At the time point of sending the downlink signal DS2, the Figure 10 shown new mode S12 is performed. The sensor controller 31 pairs with the pen 2 that sent the detected downlink signal DS2 through the new protocol and sets the reception mode for the downlink signal DS in the time slot TS1 to the new mode ( Figure 11 state S21 of ). Thereby, in the time slot TS1, communication based on the new protocol is performed.

[0115] Figure 12Part (b) shows the situation where the sensor controller 31 receives the downlink signal DS2 in the time slot TS2 within the frame F when the uplink signal US2 has been sent while in state S21. The pen 2 that sends this downlink signal DS2 is also pen 2b (a different pen 2b from the pen 2b that sends the downlink signal DS2 in time slot TS1. The same applies hereinafter). At the time point of sending the downlink signal DS, it enters Figure 10 the new mode S12 shown. The sensor controller 31 pairs with the pen 2 that has sent the detected downlink signal DS2 through the new protocol, sets the reception mode of the downlink signal DS in time slot TS2 to the new mode, and sets the transmission mode of the uplink signal US to only the new mode ( Figure 11 state S23). Thereby, communication based on the new protocol is performed in both time slots TS1 and TS2, and as the uplink signal US, only the uplink signal US2 is sent.

[0116] Figure 12 Part (c) shows the situation where the sensor controller 31 receives the downlink signal DS1 in the time slot TS2 within the frame F when the uplink signal US1 has been sent while in state S21. The pen 2 that sends this downlink signal DS1 can be either pen 2a or pen 2b. In the case of pen 2a, at the time point of sending the downlink signal DS1, it enters Figure 9 the communication mode S1 shown. On the other hand, if it is pen 2b, at the time point of sending the downlink signal DS1, it enters Figure 10 the old mode S11 shown. The sensor controller 31 pairs with the pen 2 that has sent the detected downlink signal DS1 through the old protocol, and sets the reception mode of the downlink signal DS in time slot TS2 to the old mode ( Figure 11 state S24). Thereby, communication based on the new protocol is performed in time slot TS1, and communication based on the old protocol is performed in time slot TS2.

[0117] Figure 13 Part (a) shows the situation where the sensor controller 31 receives the downlink signal DS1 in the time slot TS1 within the frame F when in state S20 and the uplink signal US1 has been sent. The pen 2 that sends the initial downlink signal DS1 according to the uplink signal US1 can be either pen 2a or pen 2b. In the case of pen 2a, at the time point of sending the downlink signal DS1, it enters Figure 9 the communication mode S1 shown. On the other hand, if it is pen 2b, at the time point of sending the downlink signal DS1, it enters Figure 10 the old mode S11 shown. The sensor controller 31 pairs with the pen 2 that has sent the detected downlink signal DS1 through the old protocol, and sets the reception mode of the downlink signal DS in time slot TS1 to the old mode (Figure 11 State S22). Thus, in time slot TS1, communication based on the old protocol is performed.

[0118] Figure 13 The (b) of shows the case where the sensor controller 31 receives the downlink signal DS2 in time slot TS2 within the frame F in which the uplink signal US2 has been transmitted when it is in state S22. The pen 2 that transmits this downlink signal DS2 is pen 2b, and at the time point when the downlink signal DS2 is transmitted, it enters Figure 10 the new mode S12 shown. The sensor controller 31 pairs with the pen 2 that has transmitted the detected downlink signal DS2 through the new protocol, and sets the reception mode of the downlink signal DS in time slot TS2 to the new mode ( Figure 11 State S25). Thus, communication based on the old protocol is performed in time slot TS1, and communication based on the new protocol is performed in time slot TS2.

[0119] Figure 13 The (c) of shows the case where the sensor controller 31 receives the downlink signal DS1 in time slot TS2 within the frame F in which the uplink signal US1 has been transmitted when it is in state S22. The pen 2 that transmits this downlink signal DS1 can be either pen 2a or pen 2b. In the case of pen 2a, at the time point when the downlink signal DS1 is transmitted, it enters Figure 9 the communication mode S1 shown. On the other hand, if it is pen 2b, at the time point when the downlink signal DS1 is transmitted, it enters Figure 10 the old mode S11 shown. The sensor controller 31 pairs with the pen 2 that has transmitted the detected downlink signal DS1 through the old protocol, sets the reception mode of the downlink signal DS in time slot TS2 to the old mode, and sets the transmission mode of the uplink signal US to only the old mode ( Figure 11 State S26). Thus, communication based on the old protocol is performed in both time slots TS1 and TS2, and as the uplink signal US, only the uplink signal US1 is transmitted.

[0120] Here, according to the above actions, even if the paired pen 2 is pen 2b corresponding to the new protocol, when the first detected uplink signal US after pen 2b approaches the touch surface is the uplink signal US1, communication starts through the old protocol. Therefore, when the sensor controller 31 starts communication through the old protocol, by referring to bit A included in the downlink signal DS1 (refer to Figure 2 ), it determines whether the pen 2 corresponds to the new protocol. If it is determined that it corresponds to the new protocol, a conversion instruction for switching to communication under the new protocol is configured in the subsequently transmitted uplink signal US1. Hereinafter, this will be described in detail with reference to Figure 14 this.

[0121] Figure 14 1 is an explanatory diagram for explaining the steps of converting the communication with the pen 2b paired with the old protocol to the new protocol. Figure 11 The steps of switching the communication with the pen 2b detected in the time slot TS1 to the new protocol in the state S20 shown in FIG. 1 are shown in (b) of FIG. 1 . Figure 11 The step of switching the communication with the pen 2b detected in the time slot TS2 to the new protocol in the state S21 shown in FIG. Figure 11 The steps of switching the communication with the pen 2b detected in the time slot TS2 to the new protocol in the state S22 shown are described below in sequence.

[0122] first, Figure 14 (a) is a case where the sensor controller 31 receives the uplink signal US1 when in state S20 and the pen 2b enters the old mode S11 and uses the time slot TS1 to send the downlink signal DS1. The sensor controller 31 that receives the downlink signal DS1 pairs with the pen 2b in the time slot TS1 through the old protocol and moves to state S22.

[0123] Then, the sensor controller 31 detects the bit A (see FIG. 1 ) contained in the downlink signal DS1 transmitted by the pen 2b in the pairing in the time slot TS1. Figure 3 (b)), it is detected that pen 2b corresponds to both the old protocol and the new protocol. In addition, since the bit A is included Figure 3 The data signal DATA shown in (b) is within the sensor controller 31, so the detection is transferred to the local scanning.

[0124] The sensor controller 31 detects that the pen 2b corresponds to both the old protocol and the new protocol, and then sends a command COMDATA (conversion command) to the pen 2b to instruct it to switch to the new protocol through the uplink signal US1 that is subsequently sent. The pen 2b that receives the command COMDATA is as shown in FIG. Figure 10 As described above, the new mode S12 is entered. Furthermore, the sensor controller 31 that receives the downlink signal DS2 sent by the pen 2b that enters the new mode S12 re-pairs with the pen 2b using the new protocol, and the reception mode of the downlink signal DS in the time slot TS1 is transferred to the state S21 of the new mode. Through the above steps, the communication with the pen 2b detected in the time slot TS1 in the state S20 is converted to the new protocol.

[0125] then, Figure 14Case (b) is a situation where the pen 2b that enters the old mode S11 by receiving the uplink signal US1 when the sensor controller 31 is in the state S21 uses the time slot TS2 to transmit the downlink signal DS1. The sensor controller 31 that has received the downlink signal DS1 pairs with the pen 2b using the old protocol in the time slot TS2 and transfers to the state S24.

[0126] Then, the sensor controller 31 detects that the pen 2b corresponds to both the old protocol and the new protocol based on the bit A included in the downlink signal DS1 transmitted by the pen 2b in the pairing in the time slot TS2 (refer to Figure 3 case (b)). Thus, the sensor controller 31 sends an instruction COMDATA (conversion instruction) indicating a conversion to the new protocol to the pen 2b in the pairing in the time slot TS2 through the subsequently transmitted uplink signal US1. The pen 2b that has received the instruction COMDATA enters the new mode S12 as described in reference to Figure 10 Moreover, the sensor controller 31 that has received the downlink signal DS2 transmitted by the pen 2b that has entered the new mode S12 re-pairs with the pen 2b using the new protocol and transfers to the state S23 where the reception mode of the downlink signal DS in the time slot TS2 becomes the new mode. Through the above steps, the communication with the pen 2b detected in the time slot TS2 in the state S21 is switched to the new protocol.

[0127] Finally, Figure 14 Case (c) is a situation where the pen 2b that enters the old mode S11 by receiving the uplink signal US1 when the sensor controller 31 is in the state S22 uses the time slot TS2 to transmit the downlink signal DS1. The sensor controller 31 that has received the downlink signal DS1 pairs with the pen 2b using the old protocol in the time slot TS2 and transfers to the state S26.

[0128] Then, the sensor controller 31 detects that the pen 2b corresponds to both the old protocol and the new protocol based on the bit A included in the downlink signal DS1 transmitted by the pen 2b in the pairing in the time slot TS2 (refer to Figure 3 case (b)). Thus, the sensor controller 31 sends an instruction COMDATA (conversion instruction) indicating a conversion to the new protocol to the pen 2b in the pairing in the time slot TS2 through the subsequently transmitted uplink signal US1. The pen 2b that has received the instruction COMDATA is as described in reference to Figure 10As described above, the new mode S12 is entered. Further, the sensor controller 31 that has received the downlink signal DS2 transmitted by the pen 2b that has entered the new mode S12 re-pairs with the pen 2b using the new protocol, and the reception mode of the downlink signal DS in the time slot TS2 is changed to the state S25 of the new mode. Through the above steps, the communication with the pen 2b detected in the time slot TS2 in the state S22 is switched to the new protocol.

[0129] As described above, according to the present embodiment, even when the sensor controller 31 is paired with the pen 2b corresponding to the new protocol through the old protocol, it can re-pair through the new protocol and start communication based on the new protocol.

[0130] As described above, according to the present embodiment, even if the pen 2a corresponding only to the old protocol receives the uplink signal SUS in a special state (for example, the uplink signal US2 based on the new protocol) from the sensor controller 31, it can operate according to the previously received uplink signal NUS. In addition, the pen 2b corresponding to both the old and new protocols can operate according to the previously received uplink signal US2 even when it receives the uplink signal US1 during communication with the sensor controller 31 based on the new protocol, and can operate according to the previously received uplink signal US1 even when it receives the uplink signal US2 during communication with the sensor controller 31 based on the old protocol. Further, the sensor controller 31 can detect both the downlink signal DS1 generated according to the old protocol and the downlink signal DS2 generated according to the new protocol in the frame F that transmits the uplink signal US1 and the frame F that transmits the uplink signal US2. Therefore, according to the present embodiment, both the pen 2a and the pen 2b can be used simultaneously in one electronic device 3.

[0131] In addition, according to the present embodiment, even when paired with the pen 2b corresponding to the new protocol through the old protocol, the pen 2b can be transferred to the new mode S12 by sending a conversion instruction from the sensor controller 31, so that communication with the pen 2b corresponding to the new protocol can be performed using the new protocol.

[0132] The preferred embodiments of the present invention have been described above. The present invention is not limited to any such embodiments, and the present invention can of course be implemented in various ways without departing from its gist.

[0133] For example, in the above embodiment, in order to convert the pen 2b that has entered the old mode S11 to the new mode S12, a conversion instruction is sent from the sensor controller 31, but the pen 2b may also autonomously convert to the new mode S12.

[0134] Figure 15It is a pattern transition diagram of the pen 2b according to the first modification of the embodiment of the present invention. As shown in this figure, when the pen 2b of this modification detects the uplink signal US2 during the entry into the old mode S11, it transfers to the new mode S12 instead of Figure 10 the continued mode S11a shown. In Figure 15 the example, the continued mode S11a is not provided. Even so, the sensor controller 31 can communicate with the pen 2b through the new protocol.

[0135] In addition, in the above embodiment, the maximum number of pens 2 that can be paired with the sensor controller 31 at the same time is 2, but the number of pens 2 that can be paired with the sensor controller 31 at the same time is not limited to 2.

[0136] Figure 16 It is a diagram showing the arrangement of transmission (Tx) and reception (Rx) in the sensor controller 31 according to the second modification of the embodiment of the present invention. As shown in this figure, in this modification, two reception channels Rx1 and Rx2 with different frequencies are used. Two time slots TS1 and TS2 are set in the reception channel Rx1, and two time slots TS3 and TS4 are set in the reception channel Rx2. Therefore, since the total number of time slots available for the transmission of the downlink signal DS is 4, according to this modification, the number of pens 2 that can be paired with the sensor controller 31 at the same time is 4.

[0137] In addition, regarding this modification, it may also be that the old protocol corresponds only to the reception channel Rx1, and the new protocol corresponds to the reception channels Rx1 and Rx2. In this case, the pen 2b corresponding to the new protocol preferably preferentially uses the time slots TS3 and TS4. Thus, as many pens 2 as possible can be used simultaneously.

[0138] In addition, the sensor controller 31 of this modification preferably changes the transmission ratio of the uplink signals US1 and US2 according to the mixing state of the downlink signal DS1 generated according to the old protocol and the downlink signal DS2 generated according to the new protocol. Specifically, it is preferable to change the above ratio in such a way that the higher the reception number of the downlink signal DS2 compared to the downlink signal DS1, the higher the transmission rate of the uplink signal US2.

[0139] In addition, in the above embodiment, as the conversion instruction transmitted by the sensor controller 31, only the case of converting the communication with the pen 2b from the old protocol to the new protocol is described, but the sensor controller 31 can also transmit a conversion instruction for converting the communication with the pen 2b from the new protocol to the old protocol.

[0140] In addition, in the above-described embodiment, when changing the communication with the pen 2b from the old protocol to the new protocol, the sensor controller 31 transmits a conversion instruction via the uplink signal US1, but it may also transmit the conversion instruction via the uplink signal US2. In this case, preferably, even when the pen 2b enters the old mode S11 or the old continuation mode S11a, it temporarily decodes the instruction signal COM in the uplink signal US2 and determines whether a conversion instruction is included. Further, when a conversion instruction is included, preferably, an operation according to the conversion instruction, that is, a conversion to the new mode S12, is executed.

[0141] In addition, in the above-described embodiment, an example in which the present invention is applied to new and old protocols (backward compatibility) has been described, but the present invention can also be applied to a multi-pen environment in which different protocols coexist. For example, even in two different protocols that are different from each other but in which the reference time of the frame is determined by the uplink signal and a part of the signals is common, the present invention can be applied.

[0142] Reference Numerals

[0143] 1 Position detection system

[0144] 2, 2a, 2b Pens

[0145] 3 Electronic device

[0146] 20 Core

[0147] 21 Tip end

[0148] 22 Tip electrode

[0149] 23 Pen pressure detection unit

[0150] 26 Power supply

[0151] 27 Integrated circuit

[0152] 30 Sensor electrode

[0153] 30X Linear electrode

[0154] 30X, 30Y Linear electrodes

[0155] 30Y Linear electrode

[0156] 31 Sensor controller

[0157] 32 Panel

[0158] 33 Electronic device control unit

[0159] 34 Liquid crystal display unit

[0160] 45 Memory

[0161] 60 MCU

[0162] 61 Logic unit

[0163] 62 Transmission unit

[0164] 63 Reception unit

[0165] 64 Selection unit

[0166] 80 Pattern supply unit

[0167] 81 Switch

[0168] 82 Code string holding unit

[0169] 83 Expansion processing unit

[0170] 84 Transmission protection unit

[0171] 85 Amplification circuit

[0172] 86 Detection circuit

[0173] 87 Analog-to-digital (AD) converter

[0174] 88x, 88y Switch

[0175] 89x, 89y Conductor selection circuit

[0176] A.B bit

[0177] COM command signal

[0178] COMDATA command

[0179] CRC error detection code

[0180] ctrl_t1~ctrl_t4, ctrl_r control signal

[0181] DATA data signal

[0182] DS Downlink signal

[0183] F Frame

[0184] NUS Uplink signal US received normally according to the old protocol

[0185] P1, P2 Indicating positions

[0186] PN spreading code

[0187] PRE Preamble

[0188] PS Position signal

[0189] RCRC Inverted error detection code

[0190] Rx1 and Rx2 receiving channels

[0191] S0 discovery mode

[0192] S1 communication mode

[0193] S0 and S10 discovery modes

[0194] S11 legacy mode

[0195] S11a legacy continuation mode

[0196] S12 new mode

[0197] S12a new continuation mode

[0198] S1a continuation mode

[0199] Trajectories st1 to st3

[0200] STA time slot status information

[0201] Control signals sTRx, sTRy, selX, and selY

[0202] SUS Special status uplink signal US

[0203] Time slots TS, TS1 to TS4

[0204] US Uplink signal

[0205] US1 Uplink signal US generated according to the legacy protocol

[0206] US2 Uplink signal US generated according to the new protocol.

Claims

1. A pen, comprising: a receiving circuit configured to receive both a first uplink signal generated according to a first protocol and a second uplink signal generated according to a second protocol different from the first protocol; a control circuit configured to control the operation of the pen in at least two operation modes; and a transmitting circuit configured to transmit a downlink signal, wherein when the receiving circuit receives the second uplink signal, the control circuit enters a second operation mode according to the second protocol, and regardless of whether the receiving circuit operating in the second operation mode receives the first uplink signal according to the first protocol or the second uplink signal according to the second protocol, the transmitting circuit operating in the second operation mode transmits a second downlink signal according to the second protocol.

2. The pen according to claim 1, wherein when the receiving circuit operating in the second operation mode does not detect the second uplink signal for a period exceeding a specified period and only detects the first uplink signal, the control circuit transfers to a discovery mode for discovering a sensor controller.

3. The pen according to claim 1, wherein when the receiving circuit operating in a first operation mode according to the first protocol receives an instruction indicating entry into the second operation mode through the first uplink signal or the second uplink signal, the control circuit transfers to the second operation mode.

4. The pen according to claim 1, wherein when the receiving circuit receives the first uplink signal, the control circuit enters a first operation mode according to the first protocol, and the transmitting circuit transmits a first downlink signal according to the first protocol, and the first downlink signal includes flag information indicating whether the pen supports only the first protocol or both the first protocol and the second protocol.

5. A sensor controller, comprising: a receiving circuit configured to detect both a first downlink signal generated according to a first protocol and a second downlink signal generated according to a second protocol different from the first protocol; and a transmitting circuit configured to transmit a first uplink signal of the first protocol in a first frame and a second uplink signal of the second protocol in a second frame, wherein the first frame and the second frame are alternately set at a set ratio, wherein the receiving circuit is further configured to detect both the first downlink signal and the second downlink signal within the second frame.

6. The sensor controller according to claim 5, wherein the receiving circuit detects both the first downlink signal and the second downlink signal within the first frame during operation.

7. The sensor controller according to claim 5, wherein the sensor controller changes the ratio according to a mixing condition of the first downlink signal and the second downlink signal during operation.

8. The sensor controller according to claim 7, wherein The sensor controller changes the ratio in such a manner that the higher the number of received second downlink signals compared to the number of received first downlink signals, the higher the transmission rate of the second uplink signal.

9. The sensor controller according to claim 5, wherein the first uplink signal and the second uplink signal include a common part.

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