Pull-up impedance calibration method and device, and electronic equipment

Abstract

The application discloses a pull-up impedance calibration method and device of LPDDR4 / NV-LPDDR4, electronic equipment and a readable storage medium. The scheme provided by the application comprises the following steps: acquiring a power supply voltage accessed by a pull-up driving module of a memory / controller of LPDDR4 / NV-LPDDR4, a voltage output high level output by the pull-up driving module, and an impedance of an on-chip termination resistor of the memory / controller; determining a theoretical impedance value of the pull-up driving module based on the power supply voltage, the voltage output high level and the impedance; and calibrating a pull-up impedance of the pull-up driving module based on the theoretical impedance value and a preset reference voltage.

Description

Technical Field

[0001] This application relates to the field of memory technology, and in particular to a pull-up impedance calibration method and apparatus for LPDDR4 / NV-LPDDR4, electronic equipment, and readable storage medium. Background Technology

[0002] The impedance calibration of existing LPDDR4 / NV-LPDDR4 memory directly sets the reference voltage VREF to the voltage value required for different calibration modes. For example, for Dynamic Random Access Memory (DRAM), the reference voltage is set to VDDQ / 3 or VDDQ / 2.5, where VDDQ is the DRAM memory's I / O power supply; for Flash Memory, the reference voltage is set to VCCQ / 3 or VCCQ / 2.5, where VCCQ is the Flash Memory's I / O power supply. Then, the On-Die Termination (ODT) impedance value RODT of the receiving end is directly copied proportionally. Based on the copied ODT impedance value RODT and the reference voltage VREF, the pull-up resistors of the memory's pull-up drive controller are calibrated. For the LPDDR4 / NV-LPDDR4 controller, one of the memory and the controller can act as a data transmitter, and the other as a receiver. The impedance calibration of the LPDDR4 / NV-LPDDR4 controller also uses the same method described above.

[0003] However, the above calibration method requires multiple different reference voltages, necessitates a built-in reference voltage generation circuit, and requires switching between different reference voltages during the calibration process. This results in a cumbersome and costly process for calibrating the pull-up impedance of LPDDR4 / NV-LPDDR4 memory or controllers. Summary of the Invention

[0004] The purpose of this application is to provide a pull-up impedance calibration method, apparatus, electronic device, and readable storage medium for LPDDR4 / NV-LPDDR4, in order to solve the problems of cumbersome and costly pull-up impedance calibration process in existing LPDDR4 / NV-LPDDR4 systems.

[0005] To solve the above-mentioned technical problems, this specification is implemented as follows:

[0006] Firstly, a pull-up impedance calibration method for LPDDR4 / NV-LPDDR4 is provided, including:

[0007] Obtain the power supply voltage connected to the pull-up driver module of the LPDDR4 / NV-LPDDR4 memory / controller, the high-level output voltage of the pull-up driver module, and the impedance of the on-chip termination resistor of the memory / controller;

[0008] Based on the power supply voltage, the high-level voltage output, and the impedance, the theoretical impedance value of the pull-up drive module is determined.

[0009] Based on the theoretical impedance value and the preset reference voltage, the pull-up impedance of the pull-up drive module is calibrated.

[0010] Optionally, the theoretical impedance value of the pull-up driver module is determined based on the power supply voltage, the high-level voltage output, and the impedance, including:

[0011] The theoretical impedance value of the pull-up driver module is determined based on the power supply voltage, the high-level voltage output, the impedance, and the following formula:

[0012]

[0013] Among them, R PU VDDQ represents the theoretical impedance value of the pull-up driver module, VOH represents the power supply voltage, and VOH represents the high-level voltage output.

[0014] Optionally, the ratio of the high voltage output level to the power supply voltage may differ depending on the calibration mode.

[0015] Optionally, based on the theoretical impedance value and a preset reference voltage, the impedance of the pull-up drive module is calibrated, including:

[0016] The simulated pull-down impedance of the pull-down driver module of the memory / controller is calibrated to the theoretical impedance value;

[0017] The pull-up impedance of the pull-up drive module is calibrated based on the simulated pull-down impedance and the preset reference voltage.

[0018] Optionally, calibrating the pull-up impedance of the pull-up drive module based on the simulated pull-down impedance and the preset reference voltage includes:

[0019] The preset reference voltage is input to the first input terminal of the comparator of the preset calibration module;

[0020] The analog pull-down impedance is input to the second input terminal of the comparator;

[0021] Based on the output of the comparator, the pull-up impedance of the pull-up drive module is calibrated.

[0022] Optionally, the preset reference voltage is the same as the reference voltage used to calibrate the pull-down impedance of the pull-down drive module, and the preset reference voltage is a fixed voltage value.

[0023] Secondly, an impedance calibration device for LPDDR4 / NV-LPDDR4 is provided, comprising:

[0024] The acquisition module is used to acquire the power supply voltage connected to the pull-up driver module of the LPDDR4 / NV-LPDDR4 memory / controller, the high-level voltage output of the pull-up driver module, and the impedance of the on-chip termination resistor of the memory / controller.

[0025] The determination module is used to determine the theoretical impedance value of the pull-up drive controller based on the power supply voltage, the voltage output high level, and the impedance.

[0026] The calibration module is used to calibrate the pull-up impedance of the pull-up drive module based on the theoretical impedance value and the preset reference voltage.

[0027] Optionally, the determining module is specifically used for:

[0028] The theoretical impedance value of the pull-up driver module is determined based on the power supply voltage, the high-level voltage output, the impedance, and the following formula:

[0029]

[0030] Among them, R PU VDDQ represents the theoretical impedance value of the pull-up driver module, VOH represents the power supply voltage, and VOH represents the high-level voltage output.

[0031] Thirdly, an electronic device is provided, including a memory and a processor electrically connected to the memory, the memory storing a computer program executable by the processor, the computer program, when executed by the processor, implementing the steps of the method described in the first aspect.

[0032] Fourthly, a computer-readable storage medium is provided that stores a stored program or instructions which, when executed by a processor, implement the steps of the method described in the first aspect.

[0033] In this embodiment, the power supply voltage connected to the pull-up driver module of the LPDDR4 / NV-LPDDR4 memory / controller, the high-level voltage output of the pull-up driver module, and the impedance of the on-chip termination resistor of the memory / controller are obtained. Based on the power supply voltage, the high-level voltage output, and the impedance, the theoretical impedance value of the pull-up driver module is determined. Based on the theoretical impedance value and a preset reference voltage, the pull-up impedance of the pull-up driver module is calibrated. Since the voltage output high-level calibration is performed using the ratio between the power supply voltage and the high-level voltage output, only a fixed reference voltage is needed. Different reference voltage generation circuits do not need to be built-in, and different reference voltages do not need to be switched during the calibration process. An externally supplied fixed reference voltage can be used to meet all application requirements, which not only saves design resources and reduces the cost of impedance calibration, but also ensures the accuracy of calibration. Attached Figure Description

[0034] The accompanying drawings, which are included to provide a further understanding of this application and form part of this application, illustrate exemplary embodiments and are used to explain this application, but do not constitute an undue limitation of this application. In the drawings:

[0035] Figure 1 This is a schematic flowchart of the pull-up impedance calibration method for LPDDR / NV-LPDDR4 according to an embodiment of this application.

[0036] Figure 2 This is a schematic diagram of the pull-up mechanism when LPDDR4 / NV-LPDDR4 is working normally, according to an embodiment of this application.

[0037] Figure 3 This is a schematic diagram illustrating the pull-up impedance calibration principle of LPDDR4 / NV-LPDDR4 in an embodiment of this application.

[0038] Figure 4 This is a structural block diagram of the pull-up impedance calibration device for LPDDR4 / NV-LPDDR4 according to an embodiment of this application.

[0039] Figure 5 This is a structural block diagram of an electronic device according to an embodiment of this application. Detailed Implementation

[0040] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application. The drawing numbers in this application are only used to distinguish the various steps in the solution and are not used to limit the execution order of the various steps. The specific execution order is subject to the description in the specification.

[0041] To address the problems existing in the prior art, this application provides a pull-up impedance calibration method for LPDDR4 / NV-LPDDR4. Figure 1 This is a schematic flowchart of the pull-up impedance calibration method for LPDDR4 / NV-LPDDR4 according to an embodiment of this application.

[0042] like Figure 1 As shown, it includes the following steps:

[0043] Step 102: The power supply voltage connected to the pull-up driver module of the LPDDR4 / NV-LPDDR4 memory / controller, the high-level output voltage of the pull-up driver module, and the impedance of the on-chip termination resistor of the memory / controller;

[0044] Step 104: Based on the power supply voltage, the high-level voltage output, and the impedance, determine the theoretical impedance value of the pull-up drive module;

[0045] Step 106: Based on the theoretical impedance value and the preset reference voltage, calibrate the pull-up impedance of the pull-up drive module.

[0046] Here, memory includes LPDDR4 / NV-LPDDR4 DRAM or flash memory, and the controller corresponds to the LPDDR4 / NV-LPDDR4 memory. The pull-up impedance calibration method for LPDDR4 / NV-LPDDR4 is applicable to both LPDDR4 / NV-LPDDR4 memory and controller. Below, in conjunction with... Figures 2 to 3 Taking LPDDR4 / NV-LPDDR4 memory as the transmitter and LPDDR4 / NV-LPDDR4 controller as the receiver as an example, this paper describes the pull-up impedance calibration method of the transmitter memory.

[0047] refer to Figure 2The IO power supply voltage connected to the pull-up driver module Mp1 of the memory is, for example, VDDQ or VCCQ. The pull-up driver module Mp1 outputs a high-level voltage VOH to the controlled object (not shown in the figure) at the receiving end and the internal termination resistor (ODT) of the pull-down chip through the transmission line. The impedance of the pull-up driver module Mp1 is RPU, and the impedance of the pull-down ODT at the receiving end is RODT.

[0048] In step 102, the power supply voltage, such as VDDQ or VCCQ, is known, and the impedance RODT of the pull-down ODT is known. Depending on the impedance calibration mode or requirements, the required output high-level voltage VOH varies and is related to the power supply voltage. For example, in the first mode, VOH is 1 / 3 of the power supply voltage, i.e., VCCQ / 3 or VDDQ / 3; in the second mode, VOH is 1 / 2.5 of the power supply voltage, i.e., VCCQ / 2.5 or VDDQ / 2.5.

[0049] Based on the solution provided in the above embodiments, optionally, the theoretical impedance value of the pull-up driver module Mp1 is determined based on the power supply voltage, the high-level voltage output, and the impedance, including:

[0050] The theoretical impedance value of the pull-up driver module Mp1 is determined based on the power supply voltage, the high-level voltage output, the impedance, and the following formula:

[0051]

[0052] Among them, R PU VDDQ represents the theoretical impedance value of the pull-up driver module, VOH represents the power supply voltage, and VOH represents the high-level voltage output.

[0053] like Figure 2 As shown, when the LPDDR4 / NV-LPDDR4 mode DRAM / FLASH is working normally, the high-level voltage output VOH is driven by the pull-up impedance R of the pull-up driver module Mp1 of the pull-up circuit at the transmitting end. PU The impedance of the transmission line through which the high-level voltage output VOH flows is negligible, determined by the impedance of the pull-down ODT at the receiving end and the impedance of the RODT.

[0054] That is, the high-level voltage output VOH is obtained by voltage division between the pull-up impedance RPU and the impedance RODT of ODT. Taking the IO power supply voltage VDDQ of DRAM memory as an example, the following formula can be obtained:

[0055]

[0056] Therefore, it can be deduced that:

[0057]

[0058] Optionally, the ratio of the high voltage output level to the power supply voltage may differ depending on the calibration mode.

[0059] For example, in the calibration mode of VOH = VDDQ / 3, That is, R PU =2*R ODT In calibration mode with VOH = VDDQ / 2.5, That is, R PU =1.5*R ODT .

[0060] As mentioned above, the impedance of the pull-down ODT is known, so the theoretical impedance R of the pull-up drive module Mp1 under different calibration modes can be calculated according to the above formula (2). PU .

[0061] After obtaining the theoretical impedance R of the pull-up driver module Mp1 PU Then, the pull-up impedance of the pull-up drive module Mp1 can be calibrated by combining the preset reference voltage, so that the actual pull-up impedance of the pull-up drive module Mp1 is as close as possible to the theoretical value.

[0062] Based on the solution provided in the above embodiments, optionally, in step 106 above, calibrating the impedance of the pull-up driver module Mp1 based on the theoretical impedance value and the preset reference voltage includes: calibrating the simulated pull-down impedance of the pull-down driver module of the memory / controller to the theoretical impedance value; and calibrating the pull-up impedance of the pull-up driver module Mp1 based on the simulated pull-down impedance and the preset reference voltage.

[0063] In this embodiment, calibrating the pull-up impedance of the pull-up drive module Mp1 based on the simulated pull-down impedance and the preset reference voltage includes: inputting the preset reference voltage into the first input terminal of the comparator of the preset calibration module; inputting the simulated pull-down impedance into the second input terminal of the comparator; and calibrating the pull-up impedance of the pull-up drive controller Mp1 based on the output of the comparator.

[0064] The first input terminal of the comparator can be either a positive input terminal or a negative input terminal. When the preset reference voltage is input to the positive input terminal of the comparator, the corresponding analog pull-down impedance is input to the negative input terminal of the comparator; when the preset reference voltage is input to the negative input terminal of the comparator, the corresponding analog pull-down impedance is input to the positive input terminal of the comparator.

[0065] The pull-up impedance calibration principle of LPDDR4 / NV-LPDDR4 in this application embodiment can be referred to Figure 3 ,like Figure 3As shown, the calibration module includes a comparator. In this embodiment, the positive input terminal of the comparator is connected to a reference voltage, and the negative input terminal of the comparator is connected to the theoretical pull-up impedance obtained by the above formula (2).

[0066] When calibrating the pull-up impedance, first calibrate the simulated pull-down impedance in the comparator of the calibration module to the theoretical pull-up impedance value, i.e. Then, the pull-up drive impedance is calibrated using a simulated pull-down impedance, when R PU and R PD The calibration is complete when the voltage level generated by the voltage divider equals the reference voltage VREF. The reference voltage VREF is preset to a fixed value throughout the calibration process.

[0067] Optionally, the preset reference voltage is the same as the reference voltage used to calibrate the pull-down impedance of the pull-down drive module Mn1, and the preset reference voltage is a fixed voltage value.

[0068] Typically, the reference voltage for calibrating the pull-down impedance is, for example, VDDQ / 2 or VCCQ / 2. Since the theoretical pull-up impedance in this embodiment corresponds to a high-level voltage output VOH that meets the requirements of the corresponding calibration mode, the pull-up impedance calibration is independent of the reference voltage value. Therefore, after calibrating the pull-down impedance, the reference voltage value can be kept at VDDQ / 2 or VCCQ / 2 without switching different reference voltage VREF values, and the calibration of the high-level voltage output VOH of the pull-up impedance after calibration can still be achieved.

[0069] The pull-up impedance calibration method for LPDDR4 / NV-LPDDR4 controllers is the same as that for memory pull-up impedance calibration. Figure 2 The sending end can be used as the controller, and the receiving end as the memory; this will not be elaborated further here.

[0070] In this embodiment, the power supply voltage connected to the pull-up driver module of the LPDDR4 / NV-LPDDR4 memory / controller, the high-level voltage output of the pull-up driver module, and the impedance of the on-chip termination resistor of the memory / controller are obtained. Based on the power supply voltage, the high-level voltage output, and the impedance, the theoretical impedance value of the pull-up driver module is determined. Based on the theoretical impedance value and a preset reference voltage, the pull-up impedance of the pull-up driver module is calibrated. Since the voltage output high-level calibration is performed using the ratio between the power supply voltage and the high-level voltage output, only a fixed reference voltage is needed. Different reference voltage generation circuits do not need to be built-in, and different reference voltages do not need to be switched during the calibration process. An externally supplied fixed reference voltage can be used to meet all application requirements, which not only saves design resources and reduces the cost of impedance calibration, but also ensures the accuracy of calibration.

[0071] The pull-up impedance calibration method for LPDDR4 / NV-LPDDR4 provided in this application embodiment can be executed by a pull-up impedance calibration device for LPDDR4 / NV-LPDDR4 memory or its corresponding controller. This application embodiment uses the pull-up impedance calibration device for LPDDR4 / NV-LPDDR4 to illustrate the pull-up impedance calibration method for LPDDR4 / NV-LPDDR4 provided in this application embodiment as an example.

[0072] refer to Figure 4 , Figure 4 This is a structural block diagram of the pull-up impedance calibration device for LPDDR4 / NV-LPDDR4 according to an embodiment of this application. Figure 4 As shown, the pull-up impedance calibration device 1000 includes: an acquisition module, used to acquire the power supply voltage connected to the pull-up driver module of the LPDDR4 / NV-LPDDR4 memory / controller, the high-level voltage output of the pull-up driver module, and the impedance of the on-chip termination resistor of the memory / controller; a determination module, used to determine the theoretical impedance value of the pull-up driver controller based on the power supply voltage, the high-level voltage output, and the impedance; and a calibration module, used to calibrate the pull-up impedance of the pull-up driver module based on the theoretical impedance value and a preset reference voltage.

[0073] Optionally, the determining module 1400 is specifically used for:

[0074] The theoretical impedance value of the pull-up driver module is determined based on the power supply voltage, the high-level voltage output, the impedance, and the following formula:

[0075]

[0076] Among them, R PU VDDQ represents the theoretical impedance value of the pull-up driver module, VOH represents the power supply voltage, and VOH represents the high-level voltage output.

[0077] Optionally, the calibration module 1600 is specifically used for:

[0078] The simulated pull-down impedance of the pull-down driver module of the memory / controller is calibrated to the theoretical impedance value;

[0079] The pull-up impedance of the pull-up drive module is calibrated based on the simulated pull-down impedance and the preset reference voltage.

[0080] In this embodiment, the power supply voltage connected to the pull-up driver module of the LPDDR4 / NV-LPDDR4 memory / controller, the high-level voltage output of the pull-up driver module, and the impedance of the on-chip termination resistor of the memory / controller are obtained. Based on the power supply voltage, the high-level voltage output, and the impedance, the theoretical impedance value of the pull-up driver module is determined. Based on the theoretical impedance value and a preset reference voltage, the pull-up impedance of the pull-up driver module is calibrated. Since the voltage output high-level calibration is performed using the ratio between the power supply voltage and the high-level voltage output, only a fixed reference voltage is needed. Different reference voltage generation circuits do not need to be built-in, and different reference voltages do not need to be switched during the calibration process. An externally supplied fixed reference voltage can be used to meet all application requirements, which not only saves design resources and reduces the cost of impedance calibration, but also ensures the accuracy of calibration.

[0081] The pull-up impedance calibration device for LPDDR4 / NV-LPDDR4 provided in the embodiments of this specification can achieve... Figures 1 to 3 The various processes implemented in the method implementation examples will not be described again here to avoid repetition.

[0082] Optionally, embodiments of this application also provide an electronic device. Figure 5 This is a structural block diagram of an electronic device according to an embodiment of this application.

[0083] like Figure 5 As shown, the electronic device 2000 includes a memory 2200 and a processor 2400 electrically connected to the memory 2200. The memory 2200 stores a computer program that can be run on the processor 2400. When the computer program is executed by the processor, it implements the various processes of any of the above embodiments of the LPDDR4 / NV-LPDDR4 pull-up impedance calibration method and can achieve the same technical effect. To avoid repetition, it will not be described again here.

[0084] This application also provides a computer-readable storage medium storing a computer program. When executed by a processor, this computer program implements the various processes of any of the above-described embodiments of the LPDDR4 / NV-LPDDR4 pull-up impedance calibration method, achieving the same technical effect. To avoid repetition, it will not be described again here. The computer-readable storage medium may be a read-only memory (ROM), a random access memory (RAM), a magnetic disk, or an optical disk.

[0085] It should be noted that, in this document, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Unless otherwise specified, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes that element.

[0086] Through the above description of the embodiments, those skilled in the art can clearly understand that the methods of the above embodiments can be implemented by means of software plus necessary general-purpose hardware platforms. Of course, they can also be implemented by hardware, but in many cases the former is a better implementation method. Based on this understanding, the technical solution of this application, in essence, or the part that contributes to the prior art, can be embodied in the form of a software product. This computer software product is stored in a storage medium (such as ROM / RAM, magnetic disk, optical disk) and includes several instructions to cause a terminal (which may be a mobile phone, computer, server, air conditioner, or network device, etc.) to execute the methods described in the various embodiments of this application.

[0087] The embodiments of this application have been described above with reference to the accompanying drawings. However, this application is not limited to the specific embodiments described above. The specific embodiments described above are merely illustrative and not restrictive. Those skilled in the art can make many other forms under the guidance of this application without departing from the spirit and scope of the claims, and all of these forms are within the protection scope of this application.

Claims

1. A method for calibrating the pull-up impedance of LPDDR4 / NV-LPDDR4, characterized in that, include: Obtain the power supply voltage connected to the pull-up drive module of the corresponding transmitting end of the LPDDR4 / NV-LPDDR4 memory / controller, the high-level output voltage of the pull-up drive module, and the impedance of the internal termination resistor of the pull-down chip of the corresponding receiving end of the memory / controller; Based on the power supply voltage, the high-level voltage output, and the impedance, the theoretical impedance value of the pull-up drive module is determined. Based on the theoretical impedance value and the preset reference voltage, the pull-up impedance of the pull-up driver module is calibrated, specifically including: calibrating the simulated pull-down impedance of the memory / controller's pull-down driver module to the theoretical impedance value; and calibrating the pull-up impedance of the pull-up driver module based on the simulated pull-down impedance and the preset reference voltage, wherein the preset reference voltage is the same as the reference voltage used to calibrate the pull-down impedance of the pull-down driver module, and the preset reference voltage is a fixed voltage value. The ratio of the high-level voltage output to the power supply voltage varies under different calibration modes, while the ratio remains a fixed value during the calibration of the pull-up impedance under the same calibration mode. Determining the theoretical impedance value of the pull-up driver module based on the power supply voltage, the high-level voltage output, and the impedance includes: determining the theoretical impedance value of the pull-up driver module based on the power supply voltage, the high-level voltage output, the impedance, and the following formula: in, This represents the theoretical impedance value of the pull-up driver module. This indicates the power supply voltage. This indicates that the voltage output is high. This represents the impedance.

2. The method as described in claim 1, characterized in that, Based on the simulated pull-down impedance and the preset reference voltage, the pull-up impedance of the pull-up drive module is calibrated, including: The preset reference voltage is input to the first input terminal of the comparator of the preset calibration module; The analog pull-down impedance is input to the second input terminal of the comparator; Based on the output of the comparator, the pull-up impedance of the pull-up drive module is calibrated.

3. A pull-up impedance calibration device for LPDDR4 / NV-LPDDR4, characterized in that, include: The acquisition module is used to acquire the power supply voltage connected to the pull-up drive module of the corresponding transmitting end of the LPDDR4 / NV-LPDDR4 memory / controller, the high-level voltage output of the pull-up drive module, and the impedance of the internal termination resistor of the pull-down chip of the corresponding receiving end of the memory / controller. A determination module is used to determine the theoretical impedance value of the pull-up drive module based on the power supply voltage, the high level of the voltage output, and the impedance. The calibration module is used to calibrate the pull-up impedance of the pull-up driver module based on the theoretical impedance value and a preset reference voltage. Specifically, it includes: calibrating the simulated pull-down impedance of the memory / controller's pull-down driver module to the theoretical impedance value; and calibrating the pull-up impedance of the pull-up driver module based on the simulated pull-down impedance and the preset reference voltage, wherein the preset reference voltage is the same as the reference voltage used to calibrate the pull-down impedance of the pull-down driver module, and the preset reference voltage is a fixed voltage value. The ratio of the high-level voltage output to the power supply voltage varies under different calibration modes, while the ratio remains a fixed value during the calibration of the pull-up impedance under the same calibration mode. The determining module is specifically used to: determine the theoretical impedance value of the pull-up drive module based on the power supply voltage, the high-level voltage output, the impedance, and the following formula: in, This represents the theoretical impedance value of the pull-up driver module. This indicates the power supply voltage. This indicates that the voltage output is high. This represents the impedance.

4. An electronic device, characterized in that, include: A memory and a processor electrically connected to the memory, the memory storing a computer program executable by the processor, the computer program, when executed by the processor, implementing the steps of the method as described in claim 1 or 2.

5. A readable storage medium, characterized in that, The readable storage medium stores a stored program or instructions that, when executed by a processor, implement the steps of the method as described in claim 1 or 2.

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