CN107733435B

CN107733435B - Signal processing method, signal processing device, storage medium and processor

Info

Publication number: CN107733435B
Application number: CN201710840716.6A
Authority: CN
Inventors: 冯鹏斐
Original assignee: Chipone Technology Beijing Co Ltd
Current assignee: Chipone Technology Beijing Co Ltd
Priority date: 2017-09-15
Filing date: 2017-09-15
Publication date: 2020-08-25
Anticipated expiration: 2037-09-15
Also published as: CN107733435A

Abstract

The invention discloses a signal processing method, a signal processing device, a storage medium and a processor. The method comprises the following steps: under a first scanning mode, scanning a plurality of buffer areas corresponding to the first scanning mode to obtain first sampling data of an active pen, wherein the plurality of buffer areas are used for storing the first sampling data, the first sampling data comprises pressure information of the active pen, and the sampling length of the first sampling data is greater than a target sampling length; and performing pressure demodulation on the first sampling data according to the peak data of the first sampling data to obtain the pressure frequency of the active pen. According to the invention, the effect of improving the demodulation precision of the active pen is achieved.

Description

Signal processing method, signal processing device, storage medium and processor

Technical Field

The present invention relates to the field of control, and in particular, to a signal processing method, apparatus, storage medium, and processor.

Background

At present, a touch IC is usually used to perform a self-compatibility detection mode, and coordinate calculation and pressure analysis of an active pen are realized through a software algorithm. However, because a Random Access Memory (RAM) has a limited space and a limited sampling rate, and sufficient Analog-to-Digital Converter (ADC) data cannot be acquired on the premise that a hit rate is greater than 100Hz, the conventional pressure detection algorithm has the problems of a small demodulation order and low accuracy.

In addition, due to the fact that a proper software demodulation algorithm and a proper filtering algorithm are not available, the existing pressure detection algorithm has the problem of large demodulation error, and the problem of low demodulation precision of the active pen is caused.

Aiming at the problem that the setup time and the hold time of the trigger in the prior art are short, an effective solution is not provided at present.

Disclosure of Invention

The invention mainly aims to provide a signal processing method, a signal processing device, a storage medium and a processor, which at least solve the problem of low demodulation precision of an active pen.

In order to achieve the above object, according to one aspect of the present invention, there is provided a signal processing method. The method comprises the following steps: under a first scanning mode, scanning a plurality of buffer areas corresponding to the first scanning mode to obtain first sampling data of an active pen, wherein the plurality of buffer areas are used for storing the first sampling data, the first sampling data comprises pressure information of the active pen, and the sampling length of the first sampling data is greater than a target sampling length; and performing pressure demodulation on the first sampling data according to the peak data of the first sampling data to obtain the pressure frequency of the active pen.

Optionally, after performing pressure demodulation on the first sampled data according to peak data of the first sampled data to obtain a pressure frequency of the active pen, the method further includes: and filtering the pressure frequency to obtain the pressure information of the active pen.

Optionally, after scanning the plurality of buffers of the active pen to obtain the first sample data of the active pen, the method further includes: switching the first scanning mode to a second scanning mode; in a second scanning mode, scanning a buffer area corresponding to the second scanning mode to obtain second sampling data of the active pen, wherein the buffer area corresponding to the second scanning mode is used for storing the second sampling data, the second sampling data is used for obtaining position information of the active pen and/or position information of a target object, and the target object is used for supporting the active pen in the process that the active pen is used; under the condition that the second sampling data is used for acquiring the position information of the active pen, processing the second sampling data to obtain the position information of the active pen; and under the condition that the second sampling data is used for acquiring the position information of the target object, processing the second sampling data to obtain the position information of the target object.

Optionally, the pressure demodulating the first sampling data according to peak data of the first sampling data to obtain the pressure frequency of the active pen includes: detecting whether the active pen is touched after processing the second sampling data; and under the condition that the active pen is detected to be touched, performing pressure demodulation on the first sampling data according to peak data of the first sampling data to obtain the pressure frequency of the active pen.

Optionally, after detecting whether the active pen is touched, the method further comprises: detecting whether scanning of a buffer area corresponding to the second scanning mode is finished or not under the condition that the active pen is not detected to be touched; after detecting that the scanning of the buffer area corresponding to the second scanning mode is finished, switching the second scanning mode into the first scanning mode; in a first scanning mode, a plurality of buffer areas of the active pen are scanned to obtain first sampling data of the active pen.

Optionally, in the first scanning mode, scanning the plurality of buffers of the active pen to obtain the first sample data of the active pen includes: scanning a first buffer area in a first pair of buffer areas under a first scanning mode, wherein the first pair of buffer areas are buffer areas needing to be scanned currently, and first sub-sampling data, second sub-sampling data and third sub-sampling data in first sampling data are stored in the first buffer area in the first pair of buffer areas; storing the first sub-sampling data from a first buffer area in a first pair of buffer areas to a first buffer area in a second pair of buffer areas, wherein the second pair of buffer areas is a buffer area which has been scanned last time, and the second buffer area in the second pair of buffer areas is used for storing sampling data obtained by scanning the first pair of buffer areas; scanning the first buffer area in the first pair of buffer areas again, and storing the second sub-sampling data from the first buffer area in the first pair of buffer areas to the first buffer area in a third pair of buffer areas, wherein the third pair of buffer areas are the buffer areas needing to be scanned next time; the method further includes scanning again the first buffer of the first pair of buffers, retaining the third sub-sampled data in the first buffer of the first pair of buffers, and storing the second sub-sampled data from the first buffer of the third pair of buffers to the second buffer of the first pair of buffers, wherein the sampled data in the second buffer of the first pair of buffers is cleared while the first buffer of the first pair of buffers is scanned.

Optionally, the pressure demodulating the first sampling data according to peak data of the first sampling data to obtain the pressure frequency of the active pen includes: acquiring a first sine wave periodicity obtained by scanning the first pair of buffer areas; acquiring a second sine wave periodicity obtained by scanning the second pair of buffer areas; acquiring a third sine wave cycle number obtained by scanning a third pair of buffer areas; acquiring the sum of the first sine wave periodicity, the second sine wave periodicity and the third sine wave periodicity to obtain a target sine wave periodicity; and performing pressure demodulation on the first sampling data according to the target sine wave periodicity and the number of sampling points of the first sampling data to obtain the pressure frequency of the active pen.

Optionally, the obtaining a first sine wave cycle number obtained by scanning the first pair of buffers comprises: acquiring a plurality of peak data of first sample data in a first pair of buffers; acquiring the number of sampling points of sampling data between a plurality of adjacent peak data in a plurality of peak data in the first pair of buffer areas, and acquiring the number of average sampling points between a plurality of adjacent peak data according to the number of sampling points; acquiring a first sine wave cycle number for scanning the first pair of buffers according to a sine wave cycle number between first peak data and second peak data of the plurality of peak data in the first pair of buffers, a sampling point number of sampling data other than the first peak data, the second peak data, and sampling data between the first peak data and the second peak data in the first sampling data, and an average sampling point number, wherein the first peak data and the second peak data are respectively located at a head position and a tail position of the plurality of peak data ordered according to time.

Alternatively, acquiring the first number of sine wave cycles for scanning the first pair of buffers, based on the number of sine wave cycles between the first peak data and the second peak data of the plurality of peak data, the number of sampling points of the first sample data excluding the first peak data, the second peak data, and the sample data between the first peak data and the second peak data, and the number of average sampling points, includes: a first sine wave cycle number CircleNum a, which is CircleNum1+ Extra _ Pt _ Num/CirclePtNum, is obtained by a first formula, where CircleNum1 is used to represent the number of sine wave cycles between first peak data and second peak data of the plurality of peak data, Extra _ Pt _ Num is used to represent the number of sampling points of the sample data other than the sample data between the first peak data, the second peak data, the first peak data, and the second peak data in the first sample data, and CirclePtNum is used to represent the number of average sampling points.

Optionally, the pressure demodulating the first sampling data according to peak data of the first sampling data to obtain the pressure frequency of the active pen includes: respectively acquiring a plurality of peak data of first sampling data in a first pair of buffer areas, a second pair of buffer areas and a third pair of buffer areas; respectively acquiring sine wave cycle numbers between first peak data and second peak data of a plurality of peak data in a first pair of buffer areas, a second pair of buffer areas and a third pair of buffer areas to obtain the sine wave cycle number between the first peak data and the second peak data corresponding to the first pair of buffer areas, the sine wave cycle number between the first peak data and the second peak data corresponding to the second pair of buffer areas and the sine wave cycle number between the first peak data and the second peak data corresponding to the third pair of buffer areas; respectively obtaining the sampling point number of sampling data except the sampling data among the first peak data, the second peak data, the first peak data and the second peak data in the first pair of buffer areas, the second pair of buffer areas and the third pair of buffer areas, and obtaining the sampling point number corresponding to the first pair of buffer areas, the sampling point number corresponding to the second pair of buffer areas and the sampling point number corresponding to the third pair of buffer areas, wherein the first peak data and the second peak data are respectively positioned at the head and the tail of a plurality of peak data sequenced according to time; respectively acquiring the sampling point number of sampling data among a plurality of peak data in a first pair of buffer areas, a second pair of buffer areas and a third pair of buffer areas and acquiring the average sampling point number among a plurality of adjacent peak data according to the sampling point number to obtain the average sampling point number corresponding to the first pair of buffer areas, the average sampling point number corresponding to the second pair of buffer areas and the average sampling point number corresponding to the third pair of buffer areas; acquiring a target sine wave cycle number according to the sine wave cycle number between first peak data and second peak data corresponding to the first pair of buffer areas, the sine wave cycle number between the first peak data and the second peak data corresponding to the second pair of buffer areas, the sine wave cycle number between the first peak data and the second peak data corresponding to the third pair of buffer areas, the sampling point number corresponding to the first pair of buffer areas, the sampling point number corresponding to the second pair of buffer areas, the sampling point number corresponding to the third pair of buffer areas, the average sampling point number corresponding to the first pair of buffer areas, the average sampling point number corresponding to the second pair of buffer areas and the average sampling point number corresponding to the third pair of buffer areas; and performing pressure demodulation on the first sampling data according to the target sine wave periodicity and the number of sampling points of the first sampling data to obtain the pressure frequency of the active pen.

Optionally, obtaining the target cycle number according to the number of sine wave cycles between the first peak data and the second peak data corresponding to the first pair of buffers, the number of sine wave cycles between the first peak data and the second peak data corresponding to the second pair of buffers, the number of sine wave cycles between the first peak data and the second peak data corresponding to the third pair of buffers, the number of sampling points corresponding to the first pair of buffers, the number of sampling points corresponding to the second pair of buffers, the number of sampling points corresponding to the third pair of buffers, the number of average sampling points corresponding to the first pair of buffers, the number of average sampling points corresponding to the second pair of buffers, and the number of average sampling points corresponding to the third pair of buffers comprises: acquiring a target sine wave cycle number CircleNum by a second formula as follows:

wherein CircleNum1 is for indicating the number of sine wave cycles between first peak data and second peak data corresponding to the first pair of buffers, CircleNum2 is for indicating the number of sine wave cycles between first peak data and second peak data corresponding to the second pair of buffers, CircleNum3 is for indicating the number of sine wave cycles between first peak data and second peak data corresponding to the third pair of buffers, Extra _ Pt _ Num1 is for indicating the number of sample points of sample data other than sample data between first peak data, second peak data, first peak data, and second peak data among the first sample data in the first pair of buffers, Extra _ Pt _ Num2 is for indicating the number of sample points of sample data other than sample data among first peak data, second peak data, first peak data, and second peak data among the first sample data in the second pair of buffers, extra _ Pt _ Num3 is used to represent the number of sample points of the first sample data in the third pair of buffers excluding the first peak data, the second peak data, and the sample data between the first peak data and the second peak data, and CirclePtNum2 is used to represent the number of sample points of the first sample data corresponding to the second pair of buffersThe number of average samples, circeptnum 3, is used to represent the number of average samples corresponding to the third pair of buffers, and circeptnumarg is used to represent the average number of samples corresponding to the first pair of buffers, the number of average samples corresponding to the second pair of buffers, and the average number of samples corresponding to the third pair of buffers.

In order to achieve the above object, according to another aspect of the present invention, there is also provided a signal processing apparatus. The device includes: the scanning unit is used for scanning a plurality of buffer areas corresponding to a first scanning mode in the first scanning mode to obtain first sampling data of the active pen, wherein the plurality of buffer areas are used for storing the first sampling data, the first sampling data comprises pressure information of the active pen, and the sampling length of the first sampling data is greater than a target sampling length; and the demodulation unit is used for carrying out pressure demodulation on the first sampling data according to the peak data of the first sampling data to obtain the pressure frequency of the active pen.

In order to achieve the above object, according to another aspect of the present invention, there is also provided a storage medium. The storage medium includes a stored program, wherein the apparatus in which the storage medium is located is controlled to execute the signal processing method of the embodiment of the present invention when the program is executed.

To achieve the above object, according to another aspect of the present invention, there is also provided a processor. The processor is used for running a program, wherein the program executes the signal processing method of the embodiment of the invention.

In the embodiment of the invention, in a first scanning mode, a plurality of buffer areas corresponding to the first scanning mode are scanned to obtain first sampling data of an active pen, wherein the plurality of buffer areas are used for storing the first sampling data, the first sampling data comprises pressure information of the active pen, and the sampling length of the first sampling data is greater than a target sampling length; and performing pressure demodulation on the first sampling data according to the peak data of the first sampling data to obtain the pressure frequency of the active pen. Due to the fact that the plurality of buffer areas are scanned, on the premise that the report rate of the active pen is not influenced, the sampling length is increased, the demodulation error is reduced by adopting a peak detection algorithm, the purpose of improving the demodulation order is achieved, the problem of low demodulation precision of the active pen is solved, and the effect of improving the demodulation precision of the active pen is achieved.

Drawings

The accompanying drawings, which are incorporated in and constitute a part of this application, illustrate embodiments of the invention and, together with the description, serve to explain the invention and not to limit the invention. In the drawings:

FIG. 1 is a flow chart of a method of signal processing according to an embodiment of the present invention;

FIG. 2 is a flow diagram of another signal processing method according to an embodiment of the invention;

FIG. 3 is a flow chart of a circular Buffer scan algorithm according to an embodiment of the present invention;

FIG. 4 is a waveform diagram of sampled data according to an embodiment of the invention;

FIG. 5 is a flow chart of a pressure demodulation method according to an embodiment of the present invention;

FIG. 6 is a schematic diagram of a measured waveform according to an embodiment of the present invention; and

fig. 7 is a schematic diagram of a signal processing apparatus according to an embodiment of the present invention.

Detailed Description

It should be noted that the embodiments and features of the embodiments in the present application may be combined with each other without conflict. The present invention will be described in detail below with reference to the embodiments with reference to the attached drawings.

In order to make the technical solutions better understood by those skilled in the art, the technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application, and it is obvious that the described embodiments are only partial embodiments of the present application, but not all embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present application.

It should be noted that the terms "first," "second," and the like in the description and claims of this application and in the drawings described above are used for distinguishing between similar elements and not necessarily for describing a particular sequential or chronological order. It should be understood that the data so used may be interchanged under appropriate circumstances such that embodiments of the application described herein may be used. Furthermore, the terms "comprises," "comprising," and "having," and any variations thereof, are intended to cover a non-exclusive inclusion, such that a process, method, system, article, or apparatus that comprises a list of steps or elements is not necessarily limited to those steps or elements expressly listed, but may include other steps or elements not expressly listed or inherent to such process, method, article, or apparatus.

Example 1

The embodiment of the invention provides a signal processing method.

Fig. 1 is a flow chart of a signal processing method according to an embodiment of the present invention. As shown in fig. 1, the method comprises the steps of:

step S102, in a first scanning mode, scanning a plurality of buffer areas corresponding to the first scanning mode to obtain first sampling data of the active pen.

In the technical solution provided in the above step S102, in the first scanning mode, a plurality of buffer areas corresponding to the first scanning mode are scanned to obtain first sampling data of the active pen, where the plurality of buffer areas are used to store the first sampling data, the first sampling data includes pressure information of the active pen, and a sampling length of the first sampling data is greater than a target sampling length.

In this embodiment, the first scan Mode may be an analog-to-digital conversion Test Mode (ADC Test Mode), and the plurality of buffers corresponding to the first scan Mode are scanned, for example, the RAM a, the RAM B, and the RAM C corresponding to the first scan Mode are cyclically scanned, wherein the RAM a includes the buffer a_IAnd A_QThe RAM B comprises a buffer B_IAnd B_QThe RAM C includes a buffer C_IAnd C_Q。

And circularly scanning the plurality of buffer areas to obtain first sampling data of the active pen, wherein the first sampling data can be ADC (analog to digital converter) data containing pressure information of the active pen and is used for pressure demodulation of the active pen. Optionally, ADC data acquisition is performed on the sensing electrode (RX) where the active pen is located, and the ADC data acquisition may be performed by using a software algorithm of a circular Buffer (Buffer) and multiple scanning, so that on the premise of not affecting a reporting rate, the sampling length of the ADC data is increased, the problem that sufficient ADC data cannot be acquired due to Ram space limitation and limited sampling rate is avoided, 1024 orders may be reached in a frequency interval of 10K, the demodulation order is increased, and the demodulation precision is greatly increased.

For example, one chip includes 3 pairs of RAMs, RAM a, RAM B, RAMC respectively. Wherein the RAM A comprises a buffer area A_IAnd A_QThe RAM B comprises a buffer B_IAnd B_QThe RAM C includes a buffer C_IAnd C_Q. Assume that the scan is currently completed for RAMB. Switching the normal scanning Mode to ADC Test Mode, scanning for the first time B_IA 1 to B_IThe first sample data stored in (1) is stored in (A)_Q(ii) a Second scan B_IA 1 to B_ITo C_I(ii) a Third scan B_IMixing C with_IThe first sample data stored in (1) is stored in (B)_Q. Since RAM C is to be used for the next scan, A_IThe sampled data of this time scanning RAM B is saved

This example is thus represented by A_I、B_IAnd B_QADC data containing pressure information is stored. In the case of completing the scanning of the RAM a or completing the scanning of the RAM C, the first sample data is stored in the same manner as the first sample data stored in the scan RAM B, which is not illustrated herein.

Optionally, after the active pen is scanned in the Normal scanning mode (Start Normal Scan), that is, after the Normal self-consistent Scan is finished, the data that is scanned and demodulated last time is saved to the designated RAM, and the data stored in the designated RAM is used for calculating the coordinates of the active pen or the coordinates of the finger later. And then switching the normal scanning mode into a first scanning mode, and scanning a plurality of buffer areas corresponding to the first scanning mode in the first scanning mode to obtain first sampling data of the active pen.

And step S104, performing pressure demodulation on the first sampling data according to the peak data of the first sampling data to obtain the pressure frequency of the active pen.

In the technical solution provided in the above step S104, the pressure demodulation is performed on the first sampling data according to peak data of the first sampling data, so as to obtain the pressure frequency of the active pen.

The first sample data has Peak data, for example, Peak points (PK1 to PKn), where PK1 is the first Peak point, PKn is the nth Peak point, and n is a natural number greater than 1. After scanning a plurality of buffer areas corresponding to the first scanning mode to obtain first sampling data of the active pen, performing pressure Demodulation (Press Demodulation) on the first sampling data according to peak data of the first sampling data to obtain pressure frequency of the active pen, wherein Demodulation errors can be reduced by adopting a peak detection algorithm and a series of filtering algorithms. Alternatively, the waveform in the ADC sampling mode may be used for pressure demodulation of the active pen.

Optionally, after scanning a plurality of buffer areas corresponding to the first scanning mode to obtain first sampling data of the active pen, starting normal scanning to perform data processing, that is, performing coordinate operation on the sampling data obtained by scanning in the normal scanning mode to obtain position information of the active pen, then judging whether the touch of the active pen is touched, and if it is detected that the active pen is touched, performing pressure demodulation on the first sampling data according to peak data of the first sampling data to obtain pressure frequency of the active pen. And if the fact that the active pen is not touched is detected, after the normal self-mutual capacitance scanning is finished, entering a first scanning mode, and continuously scanning a plurality of buffer areas corresponding to the first scanning mode in the first scanning mode to obtain first sampling data of the active pen.

Alternatively, the embodiment counts Peak points (PK 1-PKn) of the first sampled data, and CircleNum1 represents the complete sine wave period number between the first and last Peak points (PK1, PKn) of this scan, because the ADC sampling frequency (e.g., 2M) is higher than the sine wave frequency (mostly within 100K) emitted by the active pen, so there are typically several tens of sampling points in each sine wave period.

In this embodiment, due to the influence of noise, the Peak points at a short distance need to be filtered, filtering can be performed according to the calculation that the distance between the Peak points is 14.6-15.6 sampling points, and optionally, the distance between adjacent Peak points is determined<If the threshold value is 10 points, determining the points as noise points; then counting the number of sampling points between adjacent Peak points, and calculating the average value of the obtained sampling points, thereby obtaining the average value CirclePtNum of sampling points in each sampling period; and then counting the number of sampling points Extra _ Pt _ Num except the Peak points at the first and the last positions to obtain the sine wave period number of the scanning: CircleNum1+ Extra _ Pt _ Num/CirclePtNum; applying the same algorithm to the first sampling data obtained by scanning under the first scanning for the other two times, thereby obtaining sine wave cycle numbers of the three times of scanning, wherein the sine wave cycle numbers obtained by the three times of scanning are all complete sine wave cycle numbers between the head peak point and the tail peak point; and calculating the pressure frequency of the active pen according to the sine wave cycle number of the three-time scanning, the ADC sampling rate, the sampling point number at each time, for example,

to obtain

Preferably, after the pressure demodulation is performed on the first sampling data according to the peak data of the first sampling data to obtain the pressure frequency of the active pen, the pressure frequency of the active pen is filtered, for example, an average moving average filtering algorithm is applied to the first sampling data, so that the pressure value of the active pen is smoother, the demodulation error can be controlled within 10Hz, and the pressure demodulation error of the active pen is reduced.

In the embodiment, in a first scanning mode, a plurality of buffer areas corresponding to the first scanning mode are scanned to obtain first sampling data of an active pen, wherein the plurality of buffer areas are used for storing the first sampling data, the first sampling data includes pressure information of the active pen, and the sampling length of the first sampling data is greater than a target sampling length; and performing pressure demodulation on the first sampling data according to the peak data of the first sampling data to obtain the pressure frequency of the active pen. Due to the fact that the plurality of buffer areas are scanned, on the premise that the report rate of the active pen is not influenced, the sampling length is increased, the demodulation error is reduced by adopting a peak detection algorithm, the purpose of improving the demodulation order is achieved, the problem of low demodulation precision of the active pen is solved, and the effect of improving the demodulation precision of the active pen is achieved.

As an optional implementation manner, after performing pressure demodulation on the first sample data according to peak data of the first sample data to obtain a pressure frequency of the active pen in step S104, the method further includes: and filtering the pressure frequency to obtain the pressure information of the active pen.

In this embodiment, after the peak detection algorithm is used to perform pressure demodulation on the first sampling data to obtain the pressure frequency of the active pen, the obtained pressure frequency is filtered, for example, the obtained pressure frequency is subjected to moving average filtering to filter noise information in the pressure frequency, so that the obtained pressure value of the active pen is smoother, the demodulation error can be controlled within 10Hz, and the effect of reducing the demodulation error of the active pen is achieved.

As an alternative implementation, in step S102, after scanning the plurality of buffers of the active pen to obtain the first sample data of the active pen, the method further includes: switching the first scanning mode to a second scanning mode; in a second scanning mode, scanning a buffer area corresponding to the second scanning mode to obtain second sampling data of the active pen, wherein the buffer area corresponding to the second scanning mode is used for storing the second sampling data, the second sampling data is used for obtaining position information of the active pen and/or position information of a target object, and the target object is used for supporting the active pen in the process that the active pen is used; under the condition that the second sampling data is used for acquiring the position information of the active pen, processing the second sampling data to obtain the position information of the active pen; and under the condition that the second sampling data is used for acquiring the position information of the target object, processing the second sampling data to obtain the position information of the target object.

In this embodiment, after scanning the plurality of buffers of the active pen to obtain first sampling data of the active pen, the first scanning Mode is switched to a second scanning Mode, where the first scanning Mode may be an ADC Test Mode, the sampling data obtained in the first scanning Mode is used for pressure demodulation by the active pen, and the second scanning Mode is a normal scanning Mode, the sampling data obtained in the second scanning Mode is used for calculating position information of the active pen and position information of the finger, where self-contained scanning is used for detecting coordinates of the active pen, and mutual-contained scanning is used for detecting coordinates of the finger. After the first scanning mode is switched to the second scanning mode, scanning a buffer area corresponding to the second scanning mode, that is, performing normal self-compatible scanning on the active pen to obtain second sampling data of the active pen, where the buffer area corresponding to the second scanning mode is used to store the second sampling data, that is, the buffer area corresponding to the second scanning mode stores the sampling data used to obtain the position information of the active pen and/or the position information of the target object. The target object is used to support the active pen during use of the active pen, for example, the target object is a finger. And after scanning the buffer corresponding to the second scanning mode to obtain second sampling Data of the active pen, performing Data processing on the second sampling Data to perform coordinate operation, and processing the second sampling Data to obtain the position information of the active pen under the condition that the second sampling Data is used for obtaining the position information of the active pen, wherein the position information of the active pen can be indicated through the coordinate information of the active pen (Touch Data Process). And under the condition that the second sampling data is used for acquiring the position information of the target object, processing the second sampling data to obtain the position information of the target object, wherein the position information of the target object can be indicated through the coordinate information of the target object, so that the calculation of the coordinate of the active pen or the finger is realized.

As an alternative implementation, in step S104, performing pressure demodulation on the first sample data according to peak data of the first sample data to obtain a pressure frequency of the active pen includes: detecting whether the active pen is touched after processing the second sampling data; and under the condition that the active pen is detected to be touched, performing pressure demodulation on the first sampling data according to peak data of the first sampling data to obtain the pressure frequency of the active pen.

After the second sampling data is processed to obtain the position information of the active pen and/or the position information of the target object, the embodiment detects whether the active pen is touched (Stylus on), that is, whether the active pen is used. And if the active pen is detected to be touched, performing pressure demodulation on the first sampling data according to peak data of the first sampling data to obtain the pressure frequency of the active pen. After the pressure frequency of the active pen is obtained, the normal self-mutual capacitance scanning is waited for ending, then the cyclic scanning under the ADC Test Mode is carried out, the normal scanning is started, the data processing and the coordinate operation are carried out, whether the active pen is touched or not is judged, the pressure demodulation is carried out under the condition that the active pen is touched, the cyclic processing is carried out, the pressure demodulation of the active pen is realized, and the effect of improving the demodulation precision of the active pen is achieved.

As an optional embodiment, after detecting whether the active pen is touched, the method further comprises: detecting whether scanning of a buffer area corresponding to the second scanning mode is finished or not under the condition that the active pen is not detected to be touched; after detecting that the scanning of the buffer area corresponding to the second scanning mode is finished, switching the second scanning mode into the first scanning mode; in a first scanning mode, a plurality of buffer areas of the active pen are scanned to obtain first sampling data of the active pen.

After detecting whether the active pen is touched, if the active pen is not detected to be touched, detecting whether scanning of the buffer area corresponding to the second scanning mode is finished, that is, waiting for the end of normal self-mutual capacitance scanning (wait scan complete). After detecting that scanning of the buffer area corresponding to the second scanning mode is finished, switching the second scanning mode to the first scanning mode, that is, switching the normal scanning mode to the ADC Test mode. After the second scanning mode is switched to the first scanning mode, the plurality of buffer areas of the active pen are scanned, 6 buffer areas of the active pen can be circularly scanned, first sampling data of the active pen are obtained, then pressure demodulation is carried out on the first sampling data according to peak data of the first sampling data, pressure frequency of the active pen is obtained, the pressure frequency is filtered, pressure information of the active pen is obtained, and the effect of improving demodulation precision of the active pen is achieved.

As an alternative embodiment, in the first scanning mode, scanning the plurality of buffers of the active pen to obtain the first sample data of the active pen includes: scanning a first buffer area in a first pair of buffer areas under a first scanning mode, wherein the first pair of buffer areas are buffer areas needing to be scanned currently, and first sub-sampling data, second sub-sampling data and third sub-sampling data in first sampling data are stored in the first buffer area in the first pair of buffer areas; storing the first sub-sampling data from a first buffer area in a first pair of buffer areas to a first buffer area in a second pair of buffer areas, wherein the second pair of buffer areas is a buffer area which has been scanned last time, and the second buffer area in the second pair of buffer areas is used for storing sampling data obtained by scanning the first pair of buffer areas; scanning the first buffer area in the first pair of buffer areas again, and storing the second sub-sampling data from the first buffer area in the first pair of buffer areas to the first buffer area in a third pair of buffer areas, wherein the third pair of buffer areas are the buffer areas needing to be scanned next time; the method further includes scanning again the first buffer of the first pair of buffers, retaining the third sub-sampled data in the first buffer of the first pair of buffers, and storing the second sub-sampled data from the first buffer of the third pair of buffers to the second buffer of the first pair of buffers, wherein the sampled data in the second buffer of the first pair of buffers is cleared while the first buffer of the first pair of buffers is scanned.

Under this embodiment, the buffer is cyclically scanned to increase the length of the sample data for pressure demodulation. In the first scanning mode, a first buffer, e.g., RAM B, of the first pair of buffers is scanned. The first pair of buffers are buffers which need to be scanned currently, and first sample data is stored in a first buffer of the first pair of buffersOf the first, second and third sub-sampled data, e.g. B in RAM B_IFirst sub-sampling data, second sub-sampling data and third sub-sampling data in the first sampling data are saved, and the first sub-sampling data, the second sub-sampling data and the third sub-sampling data are ADC data containing pressure information. Storing the first sub-sampled data from the first buffer of the first pair of buffers to the first buffer of the second pair of buffers, for example, the second pair of buffers is a RAM a, and the RAM a includes the first buffer a_Q. First sub-sampled data from B_ITo A in RAM A_QIn (1). In this embodiment, the second pair of buffers is the buffers that have been scanned last time, and the second buffer in the second pair of buffers is used to store the sample data obtained by scanning the first pair of buffers, for example, the RAM a further includes a_I，A_IFor storing the sampling data obtained by this time of scanning RAM B

The first buffer area of the first pair of buffer areas is scanned again, and the second sub-sampled data is stored from the first buffer area of the first pair of buffer areas to the first buffer area of the third pair of buffer areas, for example, the third pair of buffer areas is a RAM C, and the RAM C includes the first buffer area as C_IAnd a second buffer C_QSecond scan B_IA 1 to B_ISecond sub-sampled data of (1) to (C)_IIn (1). The third pair of buffers of this embodiment is the buffers that need to be scanned next after the first pair of buffers is scanned.

The first buffer of the first pair of buffers is scanned again, third sub-sampled data is retained in the first buffer of the first pair of buffers, and second sub-sampled data is stored from the first buffer of the third pair of buffers to the second buffer of the first pair of buffers, e.g., scan B for a third time_IA 1 to B_IThe third sub-sample data of (1) is retained at B_IIn (C)_ISecond sub-sampled data of (1) to (B)_QIn (1). Due to the fact thatWhen a first buffer of a pair of buffers is in use, the sampled data in a second buffer of the first pair of buffers is cleared, so that the second sub-sampled data in the first buffer of the first pair of buffers cannot be directly stored in the second buffer of the first pair of buffers, i.e., B cannot be directly stored in the second buffer of the first pair of buffers_IThe second sub-sampled data in the first buffer in (B) is stored to (B)_QIn the third time, otherwise, in the second time, B_IB is removed when the third sub-sampled data in (1) is scanned_QThe second sample data stored in (c).

In this embodiment, the third pair of buffers is used for the next scan, and the second buffer of the second pair of buffers is used for storing the data of this scan, so that the first sample data containing the pressure information can be stored only by the first buffer of the second pair of buffers, the first buffer of the first pair of buffers, and the second buffer of the second pair of buffers, for example, the RAM C is used for the next scan, and the a of the RAM a is used for the next scan_ITo save the data of this scan

Can only pass through A_Q、B_I、B_QFirst sample data containing pressure information is saved.

In the embodiment, when the second pair of Buffer areas and the third pair of Buffer areas are scanned, the stored sampling data are also scanned circularly by adopting the method, so that the scanning method of the circular Buffer is realized, the length of the sampling data for pressure demodulation is increased on the premise of not influencing the reporting rate, and the demodulation precision of the active pen is further increased.

As an alternative implementation, in step S104, performing pressure demodulation on the first sample data according to peak data of the first sample data to obtain a pressure frequency of the active pen includes: acquiring a first sine wave periodicity obtained by scanning the first pair of buffer areas; acquiring a second sine wave periodicity obtained by scanning the second pair of buffer areas; acquiring a third sine wave cycle number obtained by scanning a third pair of buffer areas; acquiring the sum of the first sine wave periodicity, the second sine wave periodicity and the third sine wave periodicity to obtain a target sine wave periodicity; and performing pressure demodulation on the first sampling data according to the target sine wave periodicity and the number of sampling points of the first sampling data to obtain the pressure frequency of the active pen.

In this embodiment, the sine wave cycle number is obtained when the first pair of buffers, the second pair of buffers, and the third pair of buffers are scanned. Acquiring a first sine wave periodicity obtained by scanning the first pair of buffer areas; acquiring a second sine wave periodicity obtained by scanning the second pair of buffer areas; and acquiring a third sine wave cycle number obtained by scanning a third pair of buffer areas, wherein the acquisition methods of the first sine wave cycle number, the second sine wave cycle number and the third sine wave cycle number can be the same. For example, for the first pair of buffers, Peak points (PK 1-PKn) are counted, in the process, a Peak point with a short distance needs to be filtered due to the influence of noise, the Peak points with an adjacent Peak distance of less than 10 points can be judged as noise points and filtered, then the number of sampling points between the adjacent Peak points is counted, and the average value of the number of sampling points is calculated, so that the average value CirclePtNum of the sampling points in each sampling period is obtained. And counting the number of sampling points Extra _ Pt _ Num except the first and last Peak points, so as to obtain the first sine wave period number obtained by scanning the first pair of buffers: CircleNum + Extra _ Pt _ Num/CirclePtNum. In the same way, the same algorithm is applied to the results of two other scans in the first scan pattern, resulting in a second number of sine wave periods and a third number of sine wave periods. After the first sine wave periodicity, the second sine wave periodicity and the third sine wave periodicity are obtained, the sum of the first sine wave periodicity, the second sine wave periodicity and the third sine wave periodicity is obtained to obtain a target sine wave periodicity, and finally, pressure demodulation is performed on the first sampling data according to the target sine wave periodicity and the sampling point number of the first sampling data, so that the pressure frequency of the active pen is obtained, the pressure frequency is further filtered, the pressure information of the active pen is obtained, and the effect of improving the demodulation precision of the active pen is achieved.

As an alternative embodiment, obtaining the first number of periods of the sine wave cycle from scanning the first pair of buffers comprises: acquiring a plurality of peak data of first sample data in a first pair of buffers; acquiring the number of sampling points of sampling data between a plurality of adjacent peak data in a plurality of peak data in the first pair of buffer areas, and acquiring the number of average sampling points between a plurality of adjacent peak data according to the number of sampling points; acquiring a first sine wave cycle number for scanning the first pair of buffers according to a sine wave cycle number between first peak data and second peak data of the plurality of peak data in the first pair of buffers, a sampling point number of sampling data other than the first peak data, the second peak data, and sampling data between the first peak data and the second peak data in the first sampling data, and an average sampling point number, wherein the first peak data and the second peak data are respectively located at a head position and a tail position of the plurality of peak data ordered according to time.

This embodiment acquires, when acquiring the first sine wave cycle number obtained by scanning the first pair of buffers, a plurality of peak data of the first sample data in the first pair of buffers, which may be a plurality of peak points of the first sample data, for example, PK1 to PKn, and a complete cycle number of the sine wave between two peak points at the beginning and end (PK1, PKn) may be represented by CircleNum 1. In the process, due to the influence of noise, the Peak points with a short distance need to be filtered, filtering can be performed according to the calculation that the distance between the Peak points is 14.6-15.6 sampling points, and optionally, when the distance between the adjacent Peak points is judged to be less than 10 points of the threshold value, the Peak points are determined to be noise points. After acquiring the Peak data of the first sampling data in the first pair of buffers, acquiring the number of sampling points of the sampling data between the adjacent Peak data in the first pair of buffers, and acquiring the average number of sampling points between the adjacent Peak data according to the number of sampling points, for example, counting the number of sampling points between each adjacent Peak point, and averaging the number of sampling points between the adjacent Peak points, thereby obtaining the average number of sampling points circleptm of sampling points in each sampling period.

Acquiring the number of sampling points Extra _ Pt _ Num of sampling data in the first sampling data except the first Peak data, the second Peak data and the sampling data between the first Peak data and the second Peak data, wherein the first Peak data and the second Peak data are respectively positioned at the head and the tail of a plurality of Peak data sequenced according to time, for example, the first Peak data is a head Peak point, the second Peak data is a tail Peak point, and counting the number of sampling points of the sampling data except the head Peak point and the tail Peak point.

The number of sine wave cycles CircleNum1 between the acquisition of the first peak data and the second peak data, the number of sampling points Extra _ Pt _ Num, and the average number of sampling points CirclePtNum, the first number of sine wave cycles for scanning the first pair of buffers is acquired, and can be calculated by CircleNum1+ Extra _ Pt _ Num/CirclePtNum.

Alternatively, the second number of sine wave cycles and the third number of sine wave cycles of this embodiment may both be acquired in accordance with the acquisition method of the first number of sine wave cycles.

Acquiring a plurality of peak data of the first sample data in the second pair of buffers when acquiring the second sine wave cycle number; acquiring the number of sampling points of sampling data between a plurality of adjacent peak data in a plurality of peak data in the second pair of buffer areas, and acquiring the number of average sampling points between a plurality of adjacent peak data according to the number of sampling points; and acquiring a second sine wave cycle number for scanning the first pair of buffers according to the sine wave cycle number between the first peak data and the second peak data of the plurality of peak data in the second pair of buffers, the sampling point number of the sampling data except the first peak data, the second peak data and the sampling data between the first peak data and the second peak data in the first sampling data, and the average sampling point number.

Acquiring a plurality of peak data of the first sample data in the third pair of buffers when acquiring the third sine wave cycle number; acquiring the number of sampling points of sampling data between a plurality of adjacent peak data in a plurality of peak data in the third pair of buffer areas, and acquiring the number of average sampling points between a plurality of adjacent peak data according to the number of sampling points; and acquiring a third sine wave cycle number for scanning the third pair of buffers according to the sine wave cycle number between the first peak data and the second peak data of the plurality of peak data in the third pair of buffers, the sampling point number of the sampling data in the first sampling data except the first peak data, the second peak data and the sampling data between the first peak data and the second peak data, and the average sampling point number.

As an alternative embodiment, acquiring the first number of sine wave cycles for scanning the first pair of buffers, based on the number of sine wave cycles between the first peak data and the second peak data of the plurality of peak data, the number of sampling points of the first sample data other than the first peak data, the second peak data, and the sample data between the first peak data and the second peak data, and the number of average sampling points, includes: a first sine wave cycle number CircleNum a, which is CircleNum1+ Extra _ Pt _ Num/CirclePtNum, is obtained by a first formula, where CircleNum1 is used to represent the number of sine wave cycles between first peak data and second peak data of the plurality of peak data, Extra _ Pt _ Num is used to represent the number of sampling points of the sample data other than the sample data between the first peak data, the second peak data, the first peak data, and the second peak data in the first sample data, and CirclePtNum is used to represent the number of average sampling points.

As an alternative implementation, in step S104, performing pressure demodulation on the first sample data according to peak data of the first sample data to obtain a pressure frequency of the active pen includes: respectively acquiring a plurality of peak data of first sampling data in a first pair of buffer areas, a second pair of buffer areas and a third pair of buffer areas; respectively acquiring sine wave cycle numbers between first peak data and second peak data of a plurality of peak data in a first pair of buffer areas, a second pair of buffer areas and a third pair of buffer areas to obtain the sine wave cycle number between the first peak data and the second peak data corresponding to the first pair of buffer areas, the sine wave cycle number between the first peak data and the second peak data corresponding to the second pair of buffer areas and the sine wave cycle number between the first peak data and the second peak data corresponding to the third pair of buffer areas; respectively obtaining the sampling point number of sampling data except the sampling data among the first peak data, the second peak data, the first peak data and the second peak data in the first pair of buffer areas, the second pair of buffer areas and the third pair of buffer areas, and obtaining the sampling point number corresponding to the first pair of buffer areas, the sampling point number corresponding to the second pair of buffer areas and the sampling point number corresponding to the third pair of buffer areas, wherein the first peak data and the second peak data are respectively positioned at the head and the tail of a plurality of peak data sequenced according to time; respectively acquiring the sampling point number of sampling data among a plurality of peak data in a first pair of buffer areas, a second pair of buffer areas and a third pair of buffer areas and acquiring the average sampling point number among a plurality of adjacent peak data according to the sampling point number to obtain the average sampling point number corresponding to the first pair of buffer areas, the average sampling point number corresponding to the second pair of buffer areas and the average sampling point number corresponding to the third pair of buffer areas; acquiring a target sine wave cycle number according to the sine wave cycle number between first peak data and second peak data corresponding to the first pair of buffer areas, the sine wave cycle number between the first peak data and the second peak data corresponding to the second pair of buffer areas, the sine wave cycle number between the first peak data and the second peak data corresponding to the third pair of buffer areas, the sampling point number corresponding to the first pair of buffer areas, the sampling point number corresponding to the second pair of buffer areas, the sampling point number corresponding to the third pair of buffer areas, the average sampling point number corresponding to the first pair of buffer areas, the average sampling point number corresponding to the second pair of buffer areas and the average sampling point number corresponding to the third pair of buffer areas; and performing pressure demodulation on the first sampling data according to the target sine wave periodicity and the number of sampling points of the first sampling data to obtain the pressure frequency of the active pen.

In this embodiment, a plurality of peak data of the first sample data in the first pair of buffers, the second pair of buffers, and the third pair of buffers are acquired, respectively; respectively acquiring sine wave cycle numbers between first peak data and second peak data of a plurality of peak data in a first pair of buffer areas, a second pair of buffer areas and a third pair of buffer areas to obtain sine wave cycle numbers CircleNum1 between the first peak data and the second peak data corresponding to the first pair of buffer areas, a sine wave cycle number CircleNum2 between the first peak data and the second peak data corresponding to the second pair of buffer areas and a sine wave cycle number CircleNum3 between the first peak data and the second peak data corresponding to the third pair of buffer areas; respectively obtaining the sampling point number of the sampling data except the sampling data among the first peak data, the second peak data, the first peak data and the second peak data in the first pair of buffer areas, the second pair of buffer areas and the third pair of buffer areas, and obtaining the sampling point number Extra _ Pt _ Num1 corresponding to the first pair of buffer areas, the sampling point number Extra _ Pt _ Num2 corresponding to the second pair of buffer areas and the sampling point number Extra _ Pt _ Num3 corresponding to the third pair of buffer areas, wherein the first peak data and the second peak data are respectively positioned at the head position and the tail position of a plurality of peak data sequenced according to time; respectively obtaining the sampling point number of sampling data among a plurality of peak data in a first pair of buffer areas, a second pair of buffer areas and a third pair of buffer areas and obtaining the average sampling point number among a plurality of adjacent peak data according to the sampling point number to obtain the average sampling point number CirclePtNum1 corresponding to the first pair of buffer areas, the average sampling point number CirclePtNum2 corresponding to the second pair of buffer areas and the average sampling point number CirclePtNum3 corresponding to the third pair of buffer areas; a target sine wave number of cycles is acquired based on the number of sine wave cycles CircleNum1 between the first peak data and the second peak data corresponding to the first pair of buffers, the number of sine wave cycles CircleNum2 between the first peak data and the second peak data corresponding to the second pair of buffers, the number of sine wave cycles CircleNum3 between the first peak data and the second peak data corresponding to the third pair of buffers, the number of sampling points Extra _ Pt _ Num1 corresponding to the first pair of buffers, the number of sampling points Extra _ Pt _ Num2 corresponding to the second pair of buffers, the number of sampling points Extra _ Pt _ Num3 corresponding to the third pair of buffers, the number of average sampling points circlePtNum1 corresponding to the first pair of buffers, the number of average sampling points circlePtNum2 corresponding to the second pair of buffers, and the number of average sampling points PtlePtm 3 corresponding to the third pair of buffers, and the target sine wave data is demodulated according to the number of the first sampling cycles and the first sampling points, the pressure frequency of the active pen is obtained.

As an alternative embodiment, the acquisition of the target number of sine wave cycles from the number of sine wave cycles between the first peak data and the second peak data corresponding to the first pair of buffers, the number of sine wave cycles between the first peak data and the second peak data corresponding to the second pair of buffers, the number of sine wave cycles between the first peak data and the second peak data corresponding to the third pair of buffers, the number of sampling points corresponding to the first pair of buffers, the number of sampling points corresponding to the second pair of buffers, the number of sampling points corresponding to the third pair of buffers, the number of average sampling points corresponding to the first pair of buffers, the number of average sampling points corresponding to the second pair of buffers, and the number of average sampling points corresponding to the third pair of buffers includes: acquiring a target sine wave cycle number CircleNum by a second formula as follows:

wherein CircleNum1 is for indicating the number of sine wave cycles between first peak data and second peak data corresponding to the first pair of buffers, CircleNum2 is for indicating the number of sine wave cycles between first peak data and second peak data corresponding to the second pair of buffers, CircleNum3 is for indicating the number of sine wave cycles between first peak data and second peak data corresponding to the third pair of buffers, Extra _ Pt _ Num1 is for indicating the number of sample points of sample data other than sample data between first peak data, second peak data, first peak data, and second peak data among the first sample data in the first pair of buffers, Extra _ Pt _ Num2 is for indicating the number of sample points of sample data other than sample data among first peak data, second peak data, first peak data, and second peak data among the first sample data in the second pair of buffers, extra _ Pt _ Num3 is used to represent the third pair of the first sample data in the buffer divided by the first peak data, the second peak data, the sample data between the first peak data and the second peak dataThe number of sampling points of the other sample data, CirclePtNum1 is used to represent the average number of sampling points corresponding to the first pair of buffers, CirclePtNum2 is used to represent the average number of sampling points corresponding to the second pair of buffers, CirclePtNum3 is used to represent the average number of sampling points corresponding to the third pair of buffers, and CirclePtNumArg is used to represent the average number of sampling points corresponding to the first pair of buffers, the average number of sampling points corresponding to the second pair of buffers, and the average number of sampling points corresponding to the third pair of buffers.

In this embodiment, the above CycleNum1, CycleNum2 and CycleNum3 correspond to the complete sine wave cycle number between the first and the last two peak points during three scans respectively. Since the ADC sampling frequency (2M) is higher than the sine wave frequency (mostly within 100K) emitted by the active pen, there are typically tens of samples per sine wave period.

The embodiment adopts the circular Buffer algorithm, and can increase the sampling length on the premise of not influencing the point reporting rate, thereby increasing the demodulation precision of the active pen and greatly reducing the demodulation error.

Example 2

The signal processing method according to the embodiment of the present invention is described below with reference to preferred embodiments.

The method comprises the following steps of active pen pressure analysis overall process, wherein the most core is a cyclic Buffer scanning algorithm and a pressure demodulation algorithm, and the overall process comprises two parts: the first part is to carry out coordinate detection, detect the position information of the hand and the active pen through self-contained scanning, the coordinate of the hand is detected through the self-contained scanning, and the coordinate of the pen is detected through the self-contained scanning; the second part is pressure detection, sine wave data can be obtained through three times of scanning under the ADC Test mode (a cyclic Buffer scanning algorithm is adopted here), and pressure information can be analyzed according to the sine wave data through a pressure demodulation algorithm.

Fig. 2 is a flow chart of another signal processing method according to an embodiment of the present invention. As shown in fig. 2, the method comprises the steps of:

step S201, wait for the end of normal self-compatible scanning.

And waiting for the end of normal self-contained scanning (waitschancomplete), wherein the mutual-contained scanning is used for detecting the coordinates of the hand, and the self-contained scanning is used for detecting the coordinates of the pen, so that the position information of the pen is detected.

In step S202, three scans in the ADC Test mode are performed.

And after the normal self-capacitance scanning is finished, performing three times of scanning in the ADC Test mode by adopting a circulating Buffer scanning algorithm to obtain sine wave data.

Step S203, normal scanning is started.

After three scans in the ADC Test mode are performed, a normal scan (start normal scan) is started. Under mutual capacitance scanning, the coordinates of the finger are detected, and under a self-capacitance scanning mode, the coordinates of the active pen are detected.

And step S204, data processing and coordinate calculation are carried out.

After the normal scanning is started, data processing and coordinate operation are carried out, the position information of the finger is obtained through detecting the obtained coordinates of the finger, the position information of the active pen is obtained through detecting the obtained coordinates of the active pen, and therefore the purpose of detecting the position information of the hand pen is achieved.

In step S205, it is determined whether the active pen is touched.

After data processing and coordinate operation, whether the active pen is touched is judged (Stylus On). If the active pen is detected to be touched, step S206 is performed, and if it is determined that the active pen is not touched, step S201 is performed.

In step S206, the pressure of the active pen is demodulated.

After determining whether or not the active pen is touched, pressure Demodulation (Press Demodulation) of the active pen is performed. After the pressure demodulation of the active pen is completed, the pressure demodulation of the active pen is performed.

Three scans (cyclic Buffer scan algorithm) under the ADC Test mode are described below. ICN86xx has 3 pairs of RAMs in total, and is set as RAM A (A)_I，A_Q)、RAM A(A_I，A_Q)、RAM C(C_I，C_Q) Thus, this embodiment is actually using 6 blocks of RAM for circular scanning.

Fig. 3 is a flow chart of a circular Buffer scan algorithm according to an embodiment of the present invention. As shown in fig. 3, the method comprises the steps of:

in step S301, the normal scan Mode is switched to the ADC Test Mode scan Mode.

Assuming that the current scanning is completed by the RAM B, the normal scanning Mode is switched to the ADC Test Mode scanning Mode.

Step S302, scanning for the first time B_I。

In ADC Test Mode scan Mode, scan B for the first time_I。B_IThe sampled data stored in (c) is ADC data containing information.

Step S303, adding B_IStoring the sampled data in A_Q。

In the process of mixing B_IStoring the sampled data in A_QThen, the first scan B_IStoring the sampled data of time to A_QWherein A in RAM A_IFor storing the data of this scan

Step S304, scanning for the second time B_I。

In ADC Test Mode, scanning for the second time B_I。

Step S305, adding B_ISample data storage to C_I。

Scanning for the second time B_IStoring the sampled data of time to C_IWhere RAM C is to be used for the next scan.

Step S306, scanning for the third time B_I。

In the second scanning B_IStoring the sampled data of time to C_IThereafter, a third scan B_I。

Step S307, adding C_IStoring the sampled data in B_Q。

In the third scan B_ISince RAM C is to be used for the next scan, then C is used_IStoring the sampled data in B_Q. In addition, the first and second substrates are,due to scanning B_IWhen, B_QThe sampled data in (B) is erased, so that in the second scan (B)_IWhen it is not possible to directly react B_ITo B_QIn the third scan B, otherwise_IWhen, B_QThe sampled data in (1) is cleared.

In step S308, the ADC Test Mode scanning Mode is switched to normal scanning.

This example uses A_I、B_IAnd B_QStoring the ADC data containing the information. In the process of mixing C_IStoring the sampled data in B_QThereafter, the ADC Test Mode scanning Mode is switched to the normal scanning.

In this embodiment, when the RAM a and the RAM C are scanned, the method is the same as that from step S301 to step S302, so that as much ADC data as possible is collected without affecting the reporting rate, thereby improving the pressure demodulation accuracy.

The pressure demodulation algorithm is described below.

Fig. 4 is a waveform diagram of sampled data according to an embodiment of the invention. Fig. 5 is a flow chart of a pressure demodulation method according to an embodiment of the present invention. As shown in fig. 4 and 5, the pressure demodulation method includes the steps of:

step S501, counting Peak points.

For the first RAM storing ADC pressure data, the number (CircleNum) of Peak points (PK 1-PKn) is counted, n is a natural number larger than 1, and is 81 as shown in FIG. 4.

It should be noted that n is 81 in this embodiment for illustration only, and the Peak number is not limited to 81, and any average value of the number of points per cycle, number of sine wave cycles, pressure frequency, etc. may be obtained within the scope of the embodiment of the present invention, and are not illustrated herein.

And step S502, filtering Peak points with close distances.

According to the embodiment, due to the influence of noise, the Peak points with the shorter distance need to be filtered, the distance between every two adjacent Peak points is 14.6-15.6 sampling points according to calculation, if the distance between every two adjacent Peak points is judged to be less than 10 points, the adjacent Peak points with the distance less than 10 points are determined as the noise points, and the noise points are filtered.

In step S503, the average value of the number of dots in each sine wave cycle is counted.

After the Peak points with close distances are filtered, counting the number of sampling points between adjacent Peak points, and calculating the average value of the number of the sampling points, thereby obtaining the average value CirclePtNum of the number of the sampling points in each sampling period.

And step S504, acquiring the sine wave periodicity between the head and tail Peak points.

In this embodiment, the sine wave cycle numbers CircleNum1 between PK 1-PKn are (n-1) the sine wave cycle numbers T1-Tn-1, respectively. For example, when n is 81, the sine wave cycle number CircleNum1 is 80, and the sine wave cycles are T1 to T80, respectively.

In step S505, the number of points outside the head and tail Peak points is counted, Extra _ Pt _ Num 1.

Counting the number of sampling points Extra _ Pt _ Num except the first and last Peak points (PK1 and PK81) to obtain the sine wave period number of the current scanning: CircleNum1+ Extra _ Pt _ Num1/CirclePtNum 1.

The above-mentioned processes from step S501 to step S505 can be performed on the other two RAMs to obtain CircleNum2, CirclePtNum2, Extra _ Pt _ Num2, CircleNum3, CirclePtNum3, and Extra _ Pt _ Num 3.

Thereby obtaining the average value of the number of points in each period,

sine wave cycle number:

let the frequency of the pressure adjusted be x, then

Thereby obtaining

The pressure frequency can be 128-136K.

After the pressure frequency is obtained, a moving average filtering algorithm is performed on the demodulated frequency, so that the pressure value is smoother.

Fig. 6 is a schematic diagram of a measured waveform according to an embodiment of the present invention. As shown in FIG. 6, Section1 is an ADC sample mode waveform for active pen pressure demodulation; section2 is a mutual capacitance waveform used for the resolution of finger coordinates; section3 is a self-contained waveform used for active pen coordinate resolution.

The embodiment adopts the circular Buffer algorithm, can increase the sampling length on the premise of not influencing the report rate, adopts the peak detection algorithm and a series of filtering algorithms to reduce the demodulation error, can reach 1024 orders in a frequency interval of 10K, and can control the demodulation error within 10Hz, thereby increasing the demodulation precision of the active pen and greatly reducing the demodulation error.

It should be noted that the steps illustrated in the flowcharts of the figures may be performed in a computer system such as a set of computer-executable instructions and that, although a logical order is illustrated in the flowcharts, in some cases, the steps illustrated or described may be performed in an order different than presented herein.

Example 3

The embodiment of the invention also provides a signal processing device. It should be noted that the signal processing apparatus of this embodiment may be used to execute the signal processing method of the embodiment of the present invention.

Fig. 7 is a schematic diagram of a signal processing apparatus according to an embodiment of the present invention. As shown in fig. 7, the apparatus includes: a scanning unit 10 and a demodulation unit 20.

The scanning unit 10 is configured to scan a plurality of buffer areas corresponding to a first scanning mode in the first scanning mode to obtain first sampling data of the active pen, where the plurality of buffer areas are used to store the first sampling data, the first sampling data includes pressure information of the active pen, and a sampling length of the first sampling data is greater than a target sampling length.

And the demodulation unit 20 is configured to perform pressure demodulation on the first sampling data according to peak data of the first sampling data to obtain a pressure frequency of the active pen.

In this embodiment, the scanning unit 10 scans a plurality of buffer areas corresponding to the first scanning mode in the first scanning mode to obtain first sample data of the active pen, where the plurality of buffer areas are used to store the first sample data, the first sample data includes pressure information of the active pen, and a sampling length of the first sample data is greater than a target sampling length, and the demodulating unit 20 performs pressure demodulation on the first sample data according to peak data of the first sample data to obtain a pressure frequency of the active pen. Due to the fact that the plurality of buffer areas are scanned, on the premise that the report rate of the active pen is not influenced, the sampling length is increased, the demodulation error is reduced by adopting a peak detection algorithm, the purpose of improving the demodulation order is achieved, the problem of low demodulation precision of the active pen is solved, and the effect of improving the demodulation precision of the active pen is achieved.

Example 4

The embodiment of the invention also provides a storage medium. The storage medium includes a stored program, wherein the apparatus in which the storage medium is located is controlled to execute the signal processing method of the embodiment of the present invention when the program is executed.

Example 5

The embodiment of the invention also provides a processor. The processor is used for running a program, wherein the program executes the signal processing method of the embodiment of the invention.

It will be apparent to those skilled in the art that the modules or steps of the invention described above may be implemented by a general purpose computing device, they may be centralized on a single computing device or distributed across a network of multiple computing devices, and they may alternatively be implemented by program code that is receivable by the computing devices, and that may be stored in a memory device for execution by the computing devices, or that may be separately fabricated into individual integrated circuit modules, or that may be fabricated from multiple modules or steps within them into a single integrated circuit module. Thus, the present invention is not limited to any specific combination of hardware and software.

The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention, and various modifications and changes may be made by those skilled in the art. Any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. A signal processing method, comprising:

under a first scanning mode, scanning a plurality of buffer areas corresponding to the first scanning mode to obtain first sampling data of an active pen, wherein the plurality of buffer areas are used for storing the first sampling data, the first sampling data comprises pressure information of the active pen, and the sampling length of the first sampling data is greater than a target sampling length;

performing pressure demodulation on the first sampling data according to peak data of the first sampling data to obtain the pressure frequency of the active pen;

wherein, in the first scanning mode, scanning the plurality of buffer areas of the active pen to obtain first sample data of the active pen includes: scanning a first buffer area in a first pair of buffer areas under the first scanning mode, wherein the first pair of buffer areas are buffer areas which need to be scanned currently, and first sub-sampling data, second sub-sampling data and third sub-sampling data in the first sampling data are stored in the first buffer area in the first pair of buffer areas; storing the first sub-sampling data from a first buffer area of the first pair of buffer areas to a first buffer area of a second pair of buffer areas, wherein the second pair of buffer areas is a buffer area which has been scanned last time, and the second buffer area of the second pair of buffer areas is used for storing sampling data obtained by scanning the first pair of buffer areas; scanning the first buffer area in the first pair of buffer areas again, and storing the second sub-sampling data from the first buffer area in the first pair of buffer areas to the first buffer area in a third pair of buffer areas, wherein the third pair of buffer areas are the buffer areas needing to be scanned next time; the method further includes scanning again a first buffer of the first pair of buffers, retaining the third sub-sampled data in the first buffer of the first pair of buffers, and storing the second sub-sampled data from the first buffer of the third pair of buffers to a second buffer of the first pair of buffers, wherein the sampled data in the second buffer of the first pair of buffers is cleared while scanning the first buffer of the first pair of buffers.

2. The method of claim 1, wherein after pressure demodulating the first sampled data according to peak data of the first sampled data to obtain a pressure frequency of the active pen, the method further comprises:

and filtering the pressure frequency to obtain the pressure information of the active pen.

3. The method of claim 2, wherein after scanning the plurality of buffers of the active pen for the first sample data of the active pen, the method further comprises:

switching the first scanning mode to a second scanning mode;

in a second scanning mode, scanning a buffer area corresponding to the second scanning mode to obtain second sampling data of the active pen, wherein the buffer area corresponding to the second scanning mode is used for storing the second sampling data, the second sampling data is used for obtaining position information of the active pen and/or position information of a target object, and the target object is used for supporting the active pen in a process that the active pen is used;

processing the second sampling data to obtain the position information of the active pen under the condition that the second sampling data is used for obtaining the position information of the active pen;

and processing the second sampling data to obtain the position information of the target object under the condition that the second sampling data is used for obtaining the position information of the target object.

4. The method of claim 3, wherein pressure demodulating the first sampled data according to peak data of the first sampled data to obtain the pressure frequency of the active pen comprises:

detecting whether the active pen is touched after processing the second sampled data;

and under the condition that the active pen is detected to be touched, performing pressure demodulation on the first sampling data according to peak data of the first sampling data to obtain the pressure frequency of the active pen.

5. The method of claim 4, wherein after detecting whether the active pen is touched, the method further comprises:

detecting whether scanning of a buffer corresponding to the second scanning mode is finished or not under the condition that the active pen is not detected to be touched;

after detecting that scanning of a buffer area corresponding to the second scanning mode is finished, switching the second scanning mode to the first scanning mode;

and under the first scanning mode, scanning a plurality of buffer areas of the active pen to obtain the first sampling data of the active pen.

6. The method of claim 1, wherein pressure demodulating the first sampled data according to peak data of the first sampled data to obtain the pressure frequency of the active pen comprises:

acquiring a first sine wave periodicity obtained by scanning the first pair of buffer areas;

acquiring a second sine wave periodicity obtained by scanning the second pair of buffer areas;

acquiring a third sine wave cycle number obtained by scanning the third pair of buffer areas;

acquiring the sum of the first sine wave periodicity, the second sine wave periodicity and the third sine wave periodicity to obtain a target sine wave periodicity;

and performing pressure demodulation on the first sampling data according to the target sine wave periodicity and the number of sampling points of the first sampling data to obtain the pressure frequency of the active pen.

7. The method of claim 6, wherein obtaining a first number of sine wave cycles from scanning the first pair of buffers comprises:

obtaining a plurality of peak data of the first sample data in the first pair of buffers;

acquiring the number of sampling points of sampling data between a plurality of adjacent peak data in the plurality of peak data in the first pair of buffer areas, and acquiring the average number of sampling points between the plurality of adjacent peak data according to the number of the sampling points;

acquiring a first sine wave cycle number for scanning the first pair of buffers according to a number of sine wave cycles between first peak data and second peak data of the plurality of peak data in the first pair of buffers, a number of sampling points of the first sampling data excluding the first peak data, the second peak data, and sampling data between the first peak data and the second peak data, and the average sampling point number, wherein the first peak data and the second peak data are respectively located at a head position and a tail position of the plurality of peak data sorted by time.

8. The method according to claim 7, wherein acquiring a first number of sine wave cycles for scanning the first pair of buffers, based on a number of sine wave cycles between the first peak data and the second peak data of the plurality of peak data, a number of sampling points of the first sample data other than the first peak data, the second peak data, and sample data between the first peak data and the second peak data, and the average number of sampling points, comprises: the first sine wave cycle number CircleNum a is obtained by a first formula,

CircleNum a — CircleNum1+ Extra _ Pt _ Num/CirclePtNum, where CircleNum1 is used to represent a sine wave between first peak data and second peak data among the plurality of peak data in the first pair of buffers, Extra _ Pt _ Num is used to represent the number of sample points of the sample data other than the sample data among the first peak data, the second peak data, the first peak data, and the second peak data, and CirclePtNum is used to represent the number of average sample points.

9. The method of claim 1, wherein pressure demodulating the first sampled data according to peak data of the first sampled data to obtain the pressure frequency of the active pen comprises:

respectively acquiring a plurality of peak data of the first sample data in the first pair of buffers, the second pair of buffers and the third pair of buffers;

acquiring sine wave cycle numbers between first peak data and second peak data in the plurality of peak data in the first pair of buffer areas, the second pair of buffer areas and the third pair of buffer areas respectively to obtain the sine wave cycle number between the first peak data and the second peak data corresponding to the first pair of buffer areas, the sine wave cycle number between the first peak data and the second peak data corresponding to the second pair of buffer areas and the sine wave cycle number between the first peak data and the second peak data corresponding to the third pair of buffer areas;

respectively acquiring sampling points of sampling data except for first peak data, second peak data, and sampling data between the first peak data and the second peak data in the first pair of buffer areas, the second pair of buffer areas, and the third pair of buffer areas, and acquiring sampling points corresponding to the first pair of buffer areas, the second pair of buffer areas, and the third pair of buffer areas, wherein the first peak data and the second peak data are respectively located at the first position and the last position of the multiple peak data sorted according to time;

respectively acquiring sampling points of sampling data among a plurality of peak data in the first pair of buffer areas, the second pair of buffer areas and the third pair of buffer areas, and acquiring average sampling points among a plurality of adjacent peak data according to the sampling points to obtain average sampling points corresponding to the first pair of buffer areas, average sampling points corresponding to the second pair of buffer areas and average sampling points corresponding to the third pair of buffer areas;

acquiring target sine wave cycle numbers according to sine wave cycle numbers between the first peak data and the second peak data corresponding to the first pair of buffer areas, sine wave cycle numbers between the first peak data and the second peak data corresponding to the second pair of buffer areas, sine wave cycle numbers between the first peak data and the second peak data corresponding to the third pair of buffer areas, sampling point numbers corresponding to the first pair of buffer areas, sampling point numbers corresponding to the second pair of buffer areas, sampling point numbers corresponding to the third pair of buffer areas, average sampling point numbers corresponding to the first pair of buffer areas, average sampling point numbers corresponding to the second pair of buffer areas, and average sampling point numbers corresponding to the third pair of buffer areas;

10. The method of claim 9, acquiring a target number of sine wave cycles from the number of sine wave cycles between the first peak data and the second peak data corresponding to the first pair of buffers, the number of sine wave cycles between the first peak data and the second peak data corresponding to the second pair of buffers, the number of sine wave cycles between the first peak data and the second peak data corresponding to the third pair of buffers, the number of sampling points corresponding to the first pair of buffers, the number of sampling points corresponding to the second pair of buffers, the number of sampling points corresponding to the third pair of buffers, the number of average sampling points corresponding to the first pair of buffers, the number of average sampling points corresponding to the second pair of buffers, and the number of average sampling points corresponding to the third pair of buffers, includes: acquiring the target sine wave cycle number CircleNum by a second formula as follows:

wherein CircleNum1 is used to represent the number of sine wave cycles between the first peak data and the second peak data corresponding to the first pair of buffers, CircleNum2 is used to represent the number of sine wave cycles between the first peak data and the second peak data corresponding to the second pair of buffers, CircleNum3 is used to represent the number of sine wave cycles between the first peak data and the second peak data corresponding to the third pair of buffers, Extra _ Pt _ Num1 is used to represent the number of sample points of the first sample data in the first pair of buffers excluding sample data between the first peak data, the second peak data, the first peak data, and the second peak data, and Extra _ Pt _ Num2 is used to represent the number of sample points of the first sample data in the second pair of buffers excluding the first peak data, the second peak data, and the second peak data, Sample points of sample data other than sample data between the first peak data and the second peak data, Extra _ Pt _ Num3 for indicating sample points of sample data other than the first peak data, the second peak data, sample data between the first peak data and the second peak data among the first sample data in the third pair of buffers, CirclePtNum1 for indicating an average sample points number corresponding to the first pair of buffers, CirclePtNum2 for indicating an average sample points number corresponding to the second pair of buffers, CirclePtNum3 for indicating an average sample points number sample corresponding to the third pair of buffers, circleptnurg is used to represent the average number of samples corresponding to the first pair of buffers, the average number of samples corresponding to the second pair of buffers, and the average number of samples corresponding to the third pair of buffers.

11. A signal processing apparatus, characterized by comprising:

the scanning unit is used for scanning a plurality of buffer areas corresponding to a first scanning mode in the first scanning mode to obtain first sampling data of an active pen, wherein the plurality of buffer areas are used for storing the first sampling data, the first sampling data comprises pressure information of the active pen, and the sampling length of the first sampling data is greater than a target sampling length;

the demodulation unit is used for carrying out pressure demodulation on the first sampling data according to peak data of the first sampling data to obtain the pressure frequency of the active pen;

wherein the apparatus is further configured to scan the plurality of buffers of the active pen in the first scan mode to obtain first sample data of the active pen by: scanning a first buffer area in a first pair of buffer areas under the first scanning mode, wherein the first pair of buffer areas are buffer areas which need to be scanned currently, and first sub-sampling data, second sub-sampling data and third sub-sampling data in the first sampling data are stored in the first buffer area in the first pair of buffer areas; storing the first sub-sampling data from a first buffer area of the first pair of buffer areas to a first buffer area of a second pair of buffer areas, wherein the second pair of buffer areas is a buffer area which has been scanned last time, and the second buffer area of the second pair of buffer areas is used for storing sampling data obtained by scanning the first pair of buffer areas; scanning the first buffer area in the first pair of buffer areas again, and storing the second sub-sampling data from the first buffer area in the first pair of buffer areas to the first buffer area in a third pair of buffer areas, wherein the third pair of buffer areas are the buffer areas needing to be scanned next time; the method further includes scanning again a first buffer of the first pair of buffers, retaining the third sub-sampled data in the first buffer of the first pair of buffers, and storing the second sub-sampled data from the first buffer of the third pair of buffers to a second buffer of the first pair of buffers, wherein the sampled data in the second buffer of the first pair of buffers is cleared while scanning the first buffer of the first pair of buffers.

12. A storage medium, characterized in that the storage medium includes a stored program, wherein, when the program is executed, a device in which the storage medium is located is controlled to execute the signal processing method according to any one of claims 1 to 10.

13. A processor, characterized in that the processor is configured to run a program, wherein the program is configured to execute the signal processing method according to any one of claims 1 to 10 when running.