Usage of SUTP Data Transmission Protocol

Abstract

The present invention provides a method for using the SUTP data transmission protocol, which includes the following steps: S1. Deploy the SUTP data transmission protocol on the intelligent USB storage device interface, and integrate an APP with the SUTP data transmission protocol on the terminal device; S2. Plug the intelligent USB storage device into the terminal device, and the terminal device recognizes the intelligent USB storage device and starts the corresponding APP; S3. The intelligent USB storage device recognizes the operating system of the terminal device, and according to the characteristics of different platform systems, the APP of this system platform uses the transmission protocol corresponding to this system platform to perform an initial handshake with it to ensure the command sets and services supported by each other; S4. Operate the APP to enable the terminal device to transmit data, and during the transmission process, the SUTP data transmission protocol encrypts and authenticates the data; S5. After the data transmission is completed, perform a safe ejection operation on the intelligent USB storage device. The SUTP protocol can be compatible with multiple operating system platforms, greatly reducing the software development difficulty and cost.

Description

Technical Field

[0001] The present invention relates to the field of data processing methods, and particularly to the usage method of the SUTP data transmission protocol. Background Art

[0002] With the rapid development of technology, the functions of terminal devices (especially handheld devices) have become increasingly rich. These devices are equipped with diverse hardware and operating system platforms, such as Windows, Linux, Android, iOS, and Mac OS, etc. The continuous growth of user demands has led to the possibility that they may own multiple terminal devices of different platforms, which has caused the amount of data stored on the terminal devices to increase sharply. However, the built-in memory of terminal devices often fails to meet this growing storage demand. Therefore, users need to back up or transfer data to terminal devices of other different platforms. USB intelligent storage devices have become an ideal choice for data backup and transfer.

[0003] However, when USB intelligent storage devices on the current market communicate with terminal devices, the commonly used method is USB bulk transfer. Although this method meets the data transmission requirements to a certain extent, during the usage process, the following problems exist for different operating systems respectively:

[0004] 1. MacOS system: When implementing functions such as secure encryption management of USB intelligent storage devices on MacOS, it is necessary to customize non-standard protocols. This not only requires developing Kernel extension programs and APPs, but also a complex signature certificate application process. In addition, due to the different security levels and installation methods of different system versions, the software is difficult to install, and after installation, the transmission of custom protocol commands may fail due to permission and other issues, resulting in the inability to use functions such as the security management of USB intelligent storage devices;

[0005] 2. iOS system: When using USB intelligent storage devices for data storage on iOS, it is usually necessary to use Apple's custom transmission protocols such as the iAP2 protocol. However, using the iAP2 protocol requires applying to Apple and passing the MFI certification, and at the same time, an Apple certification chip is installed on the USB intelligent storage device. This not only increases the development difficulty and time cost, but also raises the product cost;

[0006] 3. Android system: The openness of the Android system has led to the existence of numerous manufacturers. When transmitting standard SCSI commands and custom commands based on the standard bulk transfer method, the APP is often unable to be installed or used due to system permission issues, which brings great inconvenience to users.

[0007] Therefore, it is necessary to provide a new usage method of the SUTP data transmission protocol to solve the above technical problems. Summary of the Invention

[0008] To solve the above technical problems, the present invention provides a method for using the SUTP data transmission protocol.

[0009] The method for using the SUTP data transmission protocol provided by the present invention includes the following steps: S1. Deploy the SUTP data transmission protocol on the intelligent USB storage device interface, and integrate an APP with the SUTP data transmission protocol on the terminal device;

[0010] S2. Plug the intelligent USB storage device into the USB interface of the terminal device that needs to perform data transmission. The terminal device recognizes the intelligent USB storage device and starts the corresponding APP;

[0011] S3. The intelligent USB storage device recognizes the operating system of the terminal device, and according to the characteristics of different platform systems, the APP of this system platform uses the corresponding transmission protocol of this system platform to perform an initialization handshake with it to ensure the command sets and services supported by each other, and build a communication channel;

[0012] S4. Operate the APP to make the terminal device transmit data. During the transmission process, the SUTP data transmission protocol encrypts and authenticates the data;

[0013] S5. After the data transmission is completed, perform a safe ejection operation on the intelligent USB storage device;

[0014] In step S3, the intelligent USB storage device and the terminal device building a communication channel includes the following steps:

[0015] S31. After the intelligent USB storage device is plugged into the terminal device, it first performs an initialization operation to prepare to establish communication with the terminal device;

[0016] S32. The intelligent USB storage device quickly recognizes the operating system of the terminal device through its internal recognition mechanism;

[0017] S33. According to the recognized operating system, select the protocol that matches it to build a connection with the terminal device;

[0018] In step S4, when the intelligent USB storage device recognizes that the operating system is an iOS terminal device, the data transmission steps are as follows:

[0019] The intelligent USB storage device recognizes and confirms that the operating terminal is an iOS terminal device. At the same time, after the iOS device detects a new hardware connection, it starts the device enumeration process and reads the descriptor information of the intelligent USB storage device;

[0020] The intelligent USB storage device and the APP within the iOS operating system perform an initialization handshake through the custom MTP protocol in the SUTP data transfer protocol, exchange configuration parameters, confirm the supported commands and services, and establish a communication channel;

[0021] After establishing the communication channel, the APP within the iOS operating system sends instructions through the custom MTP protocol in the SUTP data transfer protocol, and the intelligent USB storage device executes the operation and returns the result;

[0022] The intelligent USB storage device periodically sends status updates to the APP within the iOS operating system to ensure that the user is aware of the operation progress and any error messages;

[0023] The SUTP data transfer protocol includes a custom MTP protocol and a custom USB interrupt transfer protocol.

[0024] Preferably, in step S4, the data transfer steps when the intelligent USB storage device recognizes the operating system as a Mac OS computer terminal are as follows:

[0025] The intelligent USB storage device recognizes and confirms the operating terminal as a Mac OS computer terminal, and at the same time, the device sends a signal to the Mac OS computer terminal indicating that a new hardware has been connected;

[0026] The intelligent USB storage device and the APP of the Mac OS computer terminal perform an initialization handshake through the custom USB interrupt transfer protocol in the SUTP data transfer protocol, confirm the command sets and services supported by both parties, and establish a communication channel enabling both parties;

[0027] After the communication channel is established, the APP of the Mac OS computer terminal sends commands to the intelligent USB storage device. The intelligent USB storage device executes corresponding operations according to the received commands and feeds back the results to the APP of the Mac OS computer terminal.

[0028] Preferably, in step S4, the data transfer steps when the intelligent USB storage device recognizes the operating system as an Android terminal device are as follows:

[0029] The intelligent USB storage device recognizes and confirms the operating terminal as an Android terminal device, and at the same time, the device sends a signal to the Android terminal device indicating that a new hardware has been connected;

[0030] The intelligent USB storage device and the APP of the Android terminal device perform an initialization handshake through the system API, confirm the standard SCSI protocol command sets and services supported by both parties, and the APP uses the system API to establish a communication channel with the intelligent USB storage device through the standard SCSI protocol;

[0031] After the communication channel is established, the APP of the Android terminal device sends commands to the intelligent USB storage device. The intelligent USB storage device performs corresponding operations according to the received commands and feeds back the results to the APP of the Android terminal device.

[0032] Preferably, the custom MTP protocol is based on GetObject and SetObject of the MTP protocol, and customizes the MTP protocol header, operation command information, operation data length, and operation address of the MTP protocol.

[0033] Preferably, the custom USB interrupt transfer protocol redefines the data read / write direction, identifier, data transfer batches, command encoding, and data length of the command packet based on the characteristics of the standard USB Control command packet.

[0034] Compared with the related technologies, the method for using the SUTP data transfer protocol provided by the present invention has the following

[0035] Advantages:

[0036] 1. Cross-platform compatibility: The SUTP protocol can be compatible with multiple operating system platforms, including Windows, Linux, Android, iOS, and Mac OS, etc. This greatly reduces the software development difficulty and cost, enabling developers to easily develop communication software for USB intelligent storage devices for terminal devices on different platforms;

[0037] 2. Simplify installation and use: The SUTP protocol simplifies the installation and use process. Users can easily back up or transfer data to terminal devices on different platforms without complex configuration and settings, which greatly improves the user experience and convenience;

[0038] 3. Reduce product cost: Since the SUTP protocol does not require additional authentication chips or complex authentication processes, the production cost of USB intelligent storage devices can be reduced, making the product more competitive and better meeting market demands. BRIEF DESCRIPTION OF THE DRAWINGS

[0039] Figure 1 It is the complete wireframe flowchart of the method for using the SUTP data transfer protocol provided by the present invention;

[0040] Figure 2 It is the wireframe flowchart for the intelligent USB storage device and the terminal device to establish a communication channel;

[0041] Figure 3 It is the wireframe flowchart for data transfer when the intelligent USB storage device recognizes that the operating system is an iOS terminal device;

[0042] Figure 4 A wireframe flowchart for data transmission when the intelligent USB storage device recognizes that the operating system is a Mac OS computer terminal;

[0043] Figure 5 A wireframe flowchart for data transmission when the intelligent USB storage device recognizes that the operating system is an Android terminal device. Specific implementation manners

[0044] The present invention will be further described below in conjunction with the accompanying drawings and implementation manners.

[0045] Please refer to Figure 1 — Figure 5 , wherein, Figure 1 is a complete wireframe flowchart of the method for using the SUTP data transmission protocol provided by the present invention; Figure 2 is a wireframe flowchart for the intelligent USB storage device and the terminal device to establish a communication channel; Figure 3 is a wireframe flowchart for data transmission when the intelligent USB storage device recognizes that the operating system is an iOS terminal device; Figure 4 is a wireframe flowchart for data transmission when the intelligent USB storage device recognizes that the operating system is a Mac OS computer terminal; Figure 5 is a wireframe flowchart for data transmission when the intelligent USB storage device recognizes that the operating system is an Android terminal device.

[0046] In the specific implementation process, the method for using the SUTP data transmission protocol includes the following steps:

[0047] S1. Deploy the SUTP data transmission protocol on the intelligent USB storage device interface, and integrate an APP with the SUTP data transmission protocol on the terminal device, ensuring that the terminal device is running the latest operating system version. Although the SUTP data transmission protocol itself does not strictly depend on a specific terminal device version, a newer version usually provides better compatibility and performance optimization. Confirm that the terminal device has the USB OTG (On-The-Go) function or is connected to the intelligent USB storage device through a Lightning to USB adapter. In addition, it is also necessary to check whether the intelligent USB storage device can work properly on the terminal device;

[0048] S2. Connect the intelligent USB storage device to the USB interface of the terminal device through an OTG cable or a Lightning to USB adapter. At this time, the terminal device will pop up a prompt asking the user whether to allow access to the device. After the user selects "Trust", the device can be recognized. Once the device is successfully connected, if the relevant settings have been configured in advance, the terminal device system may automatically start the preset APP. If not, the user needs to manually open the installed APP that supports the SUTP data transfer protocol.

[0049] S3. After the APP is started, it will first enumerate the connected USB device to obtain its basic information, such as device ID, manufacturer name, product model, etc. Then, the application will try to establish a communication connection with the intelligent USB storage device and send commands to understand the functions and services supported by the device. To ensure the security and stability of subsequent operations, the APP will send commands to the intelligent USB storage device and create a new session. This session remains valid throughout the connection until the device is disconnected. The session ID is generated by the APP and passed to the intelligent USB storage device as an identifier.

[0050] S4. Operate the APP to make the terminal device transfer data. During the transfer process, the SUTP data transfer protocol encrypts and authenticates the data.

[0051] S5. Perform a safe ejection operation on the intelligent USB storage device after the data transfer is completed.

[0052] It should be noted that the SUTP data transfer protocol (Super USB Transfer Protocol) is composed of a custom protocol based on the MTP (Media Transfer Protocol) protocol and a custom protocol based on the USB Control (USB interrupt transfer) protocol. According to the characteristics of different platform systems and enabling the system platform APP (abbreviation of Application, meaning "APP") to use the corresponding transfer protocol, the purpose of low product cost and convenient customer use is achieved.

[0053] MTP Custom Protocol

[0054] I. Overview: Based on MTP's GetObject (retrieve object) and SetObject (send object), protocols are defined to meet the project requirements. The entire protocol includes: MTP protocol header, operation command information, operation data length, operation address, etc., as shown in the following protocol table.

[0055] II. Custom Command 1. General Command Format

[0056]

[0057]

[0058] 2.1. Write data to the sector (0x200x01) 2.1.1 Command

[0059]

[0060]

[0061] 2.1.2 Data

[0062] Sector data in units of sectors to be written to the disk.

[0063] 2.1.3 Return

[0064]

[0065] Note:

[0066] Only when the encoding returns 0x2001: OK, it means that the DATA (data) is successfully written to the disk.

[0067] 2.2 Read sector data (0x200x02)

[0068] 2.2.1 Command

[0069]

[0070]

[0071] 2.2.2 Data

[0072] Sector data in units of sectors to be written to the disk.

[0073] 2.2.3 Return

[0074]

[0075] Note: Only when the encoding returns 0x2001: OK (normal), the returned DATA (data) is valid;

[0076] USB Control (USB interrupt transfer) custom protocol

[0077] 1. Overview: According to the characteristics of the standard USB Control command packet (8 bytes), combined with the project requirements, a secondary custom protocol is made. A command packet includes: data read / write direction, identifier, number of data batches transmitted, command encoding, and data length.

[0078] Custom command

[0079] 2. General Command Format

[0080]

[0081] 2.1 Read Data from 1024 - Byte Space

[0082]

[0083] 2.2 Write Data to 1024 - Byte Space

[0084]

[0085]

[0086] Note: 1. ByteOffset: Byte offset; 2. Value: Numerical value; 3. Description: Description; 4. LittleEndian: Little - endian byte order; 5. LSB: Least significant bit; 6. MSB: Most significant bit; 7. Code: Encoding; 8. LUN: Logical unit number; 9. GetObject: Get object; 10. SendObject: Send object; 11. LBA: Logical block addressing.

[0087] In step S3, the identification between the intelligent USB storage device and the terminal device includes the following steps:

[0088] S31. Initialization stage: After the intelligent USB storage device is plugged into the terminal device, it first performs an initialization operation to prepare for establishing communication with the terminal device;

[0089] S32. Operating system identification: The intelligent USB storage device quickly identifies the operating system of the terminal device through its internal identification mechanism;

[0090] S33. According to the identified operating system, select a protocol that matches it to establish a connection with the terminal device.

[0091] Embodiment 1

[0092] When the intelligent USB storage device identifies that the operating system is an iOS terminal device, the data transfer steps are as follows:

[0093] The intelligent USB storage device identifies and confirms that the operating terminal is an iOS terminal device. At the same time, after the iOS device detects a new hardware connection, the APP enumerates the connected USB device to obtain its basic information, such as device ID, manufacturer name, product model, etc. Then, the application attempts to establish a communication connection with the intelligent USB storage device and sends a Get DeviceInfo (Get device information) command to understand the functions and services supported by the device;

[0094] The APP sends an Open Session command to the intelligent USB storage device through a custom MTP protocol, transmits the session ID, and uses the command - response mechanism of the custom MTP protocol to ensure that each command has a corresponding confirmation response. After receiving the command, the intelligent USB storage device creates a session and returns the confirmation information to the APP (all the above commands are transmitted in the form of a Package, i.e., a compressed package).

[0095] When uploading files from an iOS device to the intelligent USB storage device, the APP first calls the SendObject Info command to inform the device of the file information to be sent (such as file name, size, etc.). Then, the file data is transmitted to the device in batches through the SendObject Info command. For the download operation, the process is the opposite, that is, the file is read from the intelligent USB storage device and saved locally on the iOS device.

[0096] The APP provides a clearly visible transfer progress bar for the user, showing the current completed percentage and the estimated remaining time. This can not only help the user understand the transfer status but also facilitate the reasonable arrangement of work.

[0097] It should be noted that for iOS terminal devices: MTP (Media Transfer Protocol) is a media transfer protocol mainly used for file transfer between media devices such as digital cameras and smartphones and computers. This protocol is developed by Microsoft, adopts a command - response mechanism, and all commands are transmitted in the form of a Package, with wide applicability and high transfer efficiency. When used in iOS system APPs, usually no additional authentication is required. Therefore, a custom MTP protocol is integrated into the USB intelligent storage device, and the corresponding custom MTP protocol is also integrated into the iOS APP. When the device is connected to an iOS device, the two communicate through the custom MTP protocol to achieve file transfer and secure data management, avoiding issues such as the need for the USB intelligent storage device to pass Apple authentication.

[0098] Embodiment 2

[0099] When the intelligent USB storage device recognizes that the operating system is a Mac OS computer terminal, the data transfer steps are as follows:

[0100] The intelligent USB storage device identifies and confirms that the operating terminal is a Mac OS computer terminal. After the Mac OS computer terminal detects the connection of a new hardware, the intelligent USB storage device establishes a communication connection with the APP in the Mac OS computer terminal through a custom USB interrupt transfer protocol. Meanwhile, the APP uses the IOKit framework to start the enumeration process to obtain the basic information of the intelligent USB storage device, such as device ID, manufacturer name, product model, etc.;

[0101] After the intelligent USB storage device receives the initialization signal sent by the APP, it starts to prepare to receive commands from the APP. To ensure the reliability of communication, the APP should adopt a command-response mechanism, that is, wait for the confirmation response from the device for each command sent. This method not only improves the accuracy of data transmission but also facilitates debugging and error handling. In addition, to further enhance security, an encryption mechanism can be added during the command transmission process to ensure the security of data;

[0102] When it is necessary to upload files from a Mac OS device to the intelligent USB storage device, the APP will first send an initialization command containing file information (such as file name, size, etc.), and then transfer the file data to the device through bulk transfer. For the download operation, the process is the opposite, that is, read the file from the intelligent USB storage device and save it to the local Mac OS device through the same transfer method;

[0103] The APP provides a clearly visible transfer progress bar for users, showing the current completed percentage and the estimated remaining time. This not only helps users understand the transfer status but also facilitates the reasonable arrangement of work;

[0104] It should be noted that for the Mac OS system, the USB intelligent storage device communicates with the upper computer APP through a custom USB interrupt transfer method. This method avoids the restrictions of the system security level, making the installation and use of the APP more convenient. At the same time, through the development of firmware and the integration of custom protocols, the stable transmission of data is also ensured.

[0105] Embodiment 3

[0106] The data transfer steps when the intelligent USB storage device identifies that the operating system is an Android terminal device are as follows:

[0107] The intelligent USB storage device identifies and confirms that the operating terminal is an Android terminal device. After the user grants permission, the APP can enumerate all connected USB devices and select the target device for initialization. Then the APP establishes a connection with the intelligent USB storage device through the API provided by the libaums library;

[0108] After the intelligent USB storage device receives the initialization signal sent by the APP, it starts to prepare to receive commands from the APP. To ensure the reliability of communication, the APP should adopt a command-response mechanism, that is, wait for the confirmation response from the device for each command sent. This method not only improves the accuracy of data transmission but also facilitates debugging and error handling;

[0109] When uploading a file from an Android device to an intelligent USB storage device, the APP will first send an initialization command containing file information (such as file name, size, etc.), and then transfer the file data to the device through batch transfer, and transfer the protocol for password management through a custom USB interrupt transfer method, such as the TLS protocol (Transport Layer Security Protocol), to protect the data transfer through this protocol and enhance the security of data transfer. For the download operation, it is the opposite process, that is, read the file from the intelligent USB storage device and save it to the local Android device through the same transfer method;

[0110] The APP provides a clearly visible transfer progress bar for users, showing the current completed percentage and the estimated remaining time. This not only helps users understand the transfer status but also facilitates the reasonable arrangement of work;

[0111] It should be noted that the libaums library is an open-source library for Android that allows applications to interact with USB mass storage devices (UMS, Universal Mass Storage). The main function of this library is to enable developers to read and write data from USB storage devices such as connected USB flash drives and SD cards on Android devices without the need for users to manually mount or unmount these devices;

[0112] For Android 11 and above systems, it supports the APP to read and write data of USB intelligent storage devices through the system API (Application Programming Interface) through the standard SCSI (Small Computer System Interface) protocol; the USB interrupt transfer method can reliably transfer custom protocols without system permission issues; the security management function of the USB intelligent storage device can be implemented through a custom USB interrupt transfer method protocol. This method avoids the problem that the APP cannot be occupied due to system security issues and affects the use, and improves the compatibility and user experience of the device.

[0113] The circuits and controls involved in the present invention are all prior arts and will not be elaborated here. The above are only embodiments of the present invention and do not limit the patent scope of the present invention. Any equivalent structural or equivalent process transformation made by using the content of the specification and drawings of the present invention, or directly or indirectly applied in other related technical fields, shall be equally included in the patent protection scope of the present invention.

Claims

1. The method for using the SUTP data transmission protocol is characterized in that: The steps include: S1. Deploy the SUTP data transmission protocol on the smart USB storage device interface, and integrate an APP with the SUTP data transmission protocol on the terminal device; S2, plugging the smart USB storage device into the USB interface of the terminal device that needs to perform data transmission, and the terminal device recognizes the smart USB storage device and starts the corresponding APP; S3. The smart USB storage device identifies the operating system of the terminal device, and according to the characteristics of the operating system of the terminal device, enables the APP integrated in the terminal device to perform an initial handshake with the smart USB storage device using a transmission protocol corresponding to the operating system of the terminal device, to ensure that the command sets and services supported by each other are established, and a communication channel is established; S4. The terminal device transmits data by operating the APP. During the transmission process, the SUTP data transmission protocol encrypts and authenticates the data. S5, after the data transfer is completed, the smart USB storage device is safely ejected; In step S3, the smart USB storage device and the terminal device establish a communication channel including the following steps: S31, after being plugged into the terminal device, the intelligent USB storage device first performs an initialization operation to prepare to establish communication with the terminal device; S32, the intelligent USB storage device quickly identifies the operating system of the terminal device through its internal identification mechanism; S33, according to the identified operating system, selecting a protocol that matches the operating system and establishing a connection with the terminal device; The SUTP data transmission protocol includes a custom MTP protocol and a custom USB interrupt transmission protocol; In step S4, when the smart USB storage device identifies that the operating system is an iOS terminal device, the data transmission steps are as follows: The smart USB storage device identifies the operating terminal and confirms it as an iOS terminal device. After the iOS device detects a new hardware connection, it starts the device enumeration process and reads the descriptor information of the smart USB storage device. The smart USB storage device and the APP in the iOS operating system perform an initial handshake through the custom MTP protocol in the SUTP data transmission protocol, exchange configuration parameters, confirm supported commands and services, and establish a communication channel; After the communication channel is established, the APP in the iOS operating system sends instructions through the custom MTP protocol in the SUTP data transmission protocol, and the smart USB storage device executes the operation and returns the result; The smart USB storage device sends regular status updates to the app within the iOS operating system, ensuring that the user is aware of the progress of the operation and any error messages.

2. The method for using the SUTP data transmission protocol according to claim 1, characterized in that: In step S4, when the smart USB storage device recognizes that the operating system is a Mac OS computer terminal, the data transmission steps are as follows: The smart USB storage device identifies the operating terminal and confirms it as a Mac OS computer terminal. At the same time, the device sends a signal to the Mac OS computer terminal, indicating that new hardware has been connected; The smart USB storage device and the APP of the Mac OS computer terminal perform an initial handshake through the custom USB interrupt transmission protocol in the SUTP data transmission protocol, confirm the command sets and services supported by both parties and establish a communication channel; After the communication channel is established, the APP of the Mac OS computer terminal sends a command to the smart USB storage device. The smart USB storage device performs corresponding operations according to the received commands and feeds back the results to the APP of the Mac OS computer terminal.

3. The method for using the SUTP data transmission protocol according to claim 1, characterized in that: In step S4, when the smart USB storage device identifies that the operating system is an Android terminal device, the data transmission steps are as follows: The smart USB storage device identifies the operating terminal and confirms it as an Android terminal device. At the same time, the device sends a signal to the Android terminal device, indicating that new hardware has been connected. The smart USB storage device and the Android terminal device's APP perform an initial handshake through the system API to confirm the standard SCSI protocol command set and services supported by both parties. The APP uses the system API to establish a communication channel with the smart USB storage device through the standard SCSI protocol, and implements the security management of the smart USB storage device through a custom USB interrupt transmission mode protocol; After the communication channel is established, the APP of the Android terminal device sends a command to the smart USB storage device. The smart USB storage device performs corresponding operations according to the received commands and feeds back the results to the APP of the Android terminal device.

4. The method for using the SUTP data transmission protocol according to claim 1, characterized in that: The customized MTP protocol is based on GetObject and SetObject of the MTP protocol, and customizes the MTP protocol header, operation command information, operation data length, and operation address of the MTP protocol.

5. The method for using the SUTP data transmission protocol according to claim 1, characterized in that: The custom USB interrupt transmission protocol is based on the characteristics of the standard USB Control command packet, and redefines the data reading and writing direction, identifier, transmitted data batch, command encoding and data length of the command packet.

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