Satellite firmware upgrading system and method based on Android system

Abstract

The invention relates to the technical field of communication, in particular to a satellite firmware upgrading system and method based on an Android system, and the system comprises an Android Telephone which is used for processing and managing the communication interaction of wireless electronic communication equipment loaded with the Android system; the Framework is in communication connection with the Android Telephone through an SAT RIL, is an Android system framework layer and is used for providing an application program API interface; the SAT Modem is integrated with a satellite communication module, is connected with the Android Telephone through the Framework, and is in communication connection with a satellite module through a UART (Universal Asynchronous Receiver / Transmitter) serial port at the same time; and the SatUpgrader App is respectively in communication connection with the Android Telephone and the SAT Modem, and meanwhile, the SatUpgrader App is provided with a satellite firmware upgrading program which is used for upgrading a satellite module. According to the invention, various satellite firmware upgrading application scenes are comprehensively considered, and the updated satellite firmware can be quickly transmitted to the satellite module of the user mobile phone, so that the functional problem caused by the fact that the satellite firmware of the user mobile phone is not updated for a long time is avoided.

Description

Technical Field

[0001] The present invention relates to the field of communication technology, and in particular to an Android-based satellite firmware upgrade system and method. Background Art

[0002] With the continuous advancement and innovation of satellite communication technology, more and more consumer smartphones are equipped with satellite communication functions. In order to achieve this function, it is usually necessary to integrate a dedicated satellite communication module into the smartphone so that it can communicate effectively with the satellite network. These satellite communication modules are pre-burned with specific satellite firmware, similar to the software version in ordinary mobile phones. Whenever a new update of the satellite firmware is released, users need to upgrade the satellite firmware and burn the latest firmware version into the satellite module of the mobile phone to ensure the normal operation of its functions and improve its performance.

[0003] At present, most smartphones automatically check the version number of satellite firmware when they are turned on, and upgrade the firmware as needed. However, with the increasing richness and diversity of satellite functions in smartphones, this single firmware upgrade solution can no longer meet the increasingly complex upgrade needs. In order to ensure the stability and reliability of satellite communication functions, the phone needs a complete and efficient satellite firmware upgrade solution in different scenarios such as restarting, manually turning on or off the satellite communication function by the user, and performing OTA (Over-The-Air) upgrades. This solution not only needs to be able to cope with various emergencies, but also ensure the simplicity and security of the upgrade process, so as to provide users with a smoother and more reliable satellite communication experience.

[0004] To achieve this goal, smartphone manufacturers and software developers are constantly exploring and optimizing satellite firmware upgrade mechanisms. They have developed smarter firmware upgrade algorithms that can automatically select the best time and method for upgrading based on user habits and network environment. For example, some smartphones will automatically upgrade their firmware at night when users are not using their phones to avoid affecting their normal use. In addition, in order to improve the reliability and security of upgrades, many mobile phones have also introduced a double verification mechanism to ensure that only verified firmware can be burned into the satellite module.

[0005] At the same time, in order to deal with the compatibility issues of different satellite communication modules, smartphone manufacturers are also actively promoting the standardization process. They have cooperated with satellite communication technology providers to jointly develop a series of standard interfaces and protocols so that smartphones of different brands can be better compatible with various satellite communication modules. This not only reduces the R&D costs of manufacturers, but also makes it easier for users to continue to use the original satellite communication modules when changing their phones.

[0006] In general, with the continuous development of satellite communication technology, the satellite communication function in smartphones will become more popular and powerful. In order to ensure the stability and reliability of this function, a complete and efficient satellite firmware upgrade solution is essential. By continuously optimizing the upgrade mechanism, introducing intelligent algorithms and standardized interfaces, smartphone manufacturers and software developers are working hard to provide users with a smoother and more reliable satellite communication experience.

[0007] When the phone leaves the factory, an initial version of satellite firmware will be burned into the satellite module. When the satellite firmware is subsequently updated, the satellite firmware needs to be placed in the system software package, and upgraded to the user's phone through OTA along with the system version, and installed in the system / etc directory. After the system version upgrade is completed, turn on the phone and determine whether the satellite firmware bin file version number in the system / etc directory is consistent with the current satellite module firmware version number. If the bin file version number is newer, then execute the satellite firmware upgrade. Summary of the invention

[0008] In view of the deficiencies in the prior art, the present invention discloses a satellite firmware upgrade system and method based on the Android system, which are used to solve the above problems.

[0009] The present invention is achieved through the following technical solutions:

[0010] In a first aspect, the present invention provides a satellite firmware upgrade system based on an Android system, comprising:

[0011] Android Telephony, which is used to process and manage the communication interactions of wireless electronic communication devices running Android system;

[0012] Framework, which is connected to the Android Telephony through SAT RIL, is the Android system framework layer and is used to provide an application program API interface;

[0013] SAT Modem, integrated with a satellite communication module, connected to the Android Telephony through the Framework, and connected to the satellite module through a UART serial port;

[0014] The SatUpgrader App is respectively connected to the Android Telephony and the SAT Modem for communication, and is provided with a satellite firmware upgrade program for upgrading the satellite module.

[0015] Furthermore, the Android Telephony system receives the initialization completion broadcast from the satellite module through the SAT Modem, indicating that the satellite communication module has been successfully started and is ready. This process ensures that the device can communicate through the satellite network and provide users with reliable connection services.

[0016] Furthermore, the SatUpgrader application (App) includes a user interface that is specifically designed to display and present detailed progress and status information during the satellite firmware upgrade process. Through this interface, users can clearly understand the various stages of the current upgrade, such as initialization, downloading firmware, verifying files, transferring data, and the final completion status.

[0017] In addition, the user interface will provide real-time feedback, displaying the current progress bar, percentage, and estimated remaining time, ensuring that users can understand the progress of the upgrade in real time. During the upgrade process, if any errors or abnormalities occur, the user interface will also display the corresponding error messages or warning prompts in a timely manner to help users quickly identify the problem and take appropriate solutions.

[0018] Furthermore, the SatUpgrader application not only includes basic upgrade functions, but also has a firmware verification module. The main responsibility of this module is to perform a comprehensive and detailed integrity check on the firmware file to be used before the firmware upgrade process begins. Through this process, it can be ensured that the firmware file has not been tampered with or damaged, thereby ensuring the security and stability of the device during the upgrade process.

[0019] Specifically, the firmware verification module uses various algorithms and technical means to check key information such as the digital signature and hash value of the firmware file to verify its authenticity and integrity.

[0020] Furthermore, after receiving the firmware upgrade instruction, the SAT Modem will start a specific upgrade process. First, it will establish a communication connection with the satellite module through the UART serial port. The UART serial port is a commonly used serial communication interface that can ensure stable data transmission. Once the communication connection is successfully established, the SAT Modem will call the satellite firmware upgrade program, which is responsible for handling the entire upgrade process.

[0021] Next, the SAT Modem will transfer the firmware file from the local storage device to the satellite module. This firmware file contains the latest software code and improvements that can enhance the performance and functionality of the satellite module. During the transmission process, the SAT Modem will ensure the integrity and reliability of the data to avoid any transmission errors that may cause the upgrade to fail.

[0022] After the transfer is complete, the SAT Modem will control the satellite module to perform the firmware upgrade operation. This usually involves writing the new firmware to the module's memory and ensuring the normal operation of the module during the upgrade process. The upgrade operation may include restarting the module, verifying the correctness of the firmware, and completing necessary configuration changes. The entire upgrade process will be carried out under the precise control of the SAT Modem to ensure that the upgrade is carried out smoothly and will not affect the normal operation of the satellite module.

[0023] Furthermore, the SAT RIL is responsible for forwarding the upgrade instruction from the SatUpgrader App to the SAT Modem during the upgrade process, and reporting the status information of the upgrade process to the SatUpgrader App.

[0024] Furthermore, the Android Telephony is used to determine whether the satellite module is turned on. If the satellite module is turned off, the satellite module is automatically turned on to check whether the firmware needs to be upgraded. If an upgrade is required, the SatUpgrader App is notified to start the satellite firmware upgrade program.

[0025] In a second aspect, the present invention provides a satellite firmware upgrade method based on the Android system, the method using the satellite firmware upgrade system based on the Android system described in the first aspect, comprising the following steps:

[0026] Check whether the satellite module of the wireless electronic communication device is turned on. If it is turned on, wait for its initialization to complete and send a broadcast to Android Telephony;

[0027] Android Telephony detects wireless device broadcasts and checks whether there is a new satellite firmware bin file in the system / etc directory;

[0028] Check for firmware updates. If a new version is found, Android Telephony obtains the current firmware number of the satellite module through the Framework API. If no new version is found, it continues to check.

[0029] Check the satellite module firmware version. If it is lower than the new version, notify to start SatUpgrader App to upgrade, update the firmware through the UART serial port and restart the device. If it is not lower, no action is taken.

[0030] Furthermore, in the method, after the satellite firmware is upgraded, Android Telephony will check the status of the satellite module when it is powered on for the first time. If the module is turned off, it will automatically turn on and check for firmware upgrade requirements. If there is a firmware upgrade requirement, it will control the SatUpgrader App to perform the upgrade;

[0031] During restart, if the satellite module is turned off, no action will be taken; if it is turned on, the Telephony app will check for firmware upgrade requirements after the satellite module is initialized. If there is a firmware upgrade requirement, it will control the SatUpgrader App to perform the upgrade.

[0032] Furthermore, in the method, after the user manually turns on the satellite module, after recognizing and receiving the initialization completion signal, it is checked whether a firmware upgrade is required. If necessary, the SatUpgrader App is controlled to start the upgrade program.

[0033] The beneficial effects of the present invention are:

[0034] Based on the existing Android system, the present invention has carefully designed and developed three main modules: FrameworkAPI, Telephony application and SatUpgrader App. These modules each have different functional responsibilities, making the design of the entire system more reasonable and the process clearer. This innovative design method enables the present invention to be widely used in various satellite mobile phone devices based on the Android system.

[0035] First, the Framework API module, as the core of the entire system, is responsible for providing the underlying interface support to ensure that other modules can interact smoothly with the Android system. Secondly, the Telephony application module focuses on processing telephone functions related to satellite communications, allowing users to enjoy a more stable and efficient communication experience when using satellite phones. Finally, the SatUpgrader App module is mainly responsible for upgrading the satellite firmware, ensuring that the satellite module in the user's mobile phone can receive the latest firmware updates in a timely manner.

[0036] During the design process, the present invention fully considers various scenarios of satellite firmware upgrades, including but not limited to online upgrades, offline upgrades, and emergency upgrades. Through comprehensive consideration of these scenarios, the present invention can ensure that the satellite firmware can be quickly and accurately transmitted to the user's satellite mobile phone module after the update. In this way, users do not need to worry about functional problems caused by the long-term non-update of satellite firmware, thereby greatly improving the user experience and the reliability of the device. BRIEF DESCRIPTION OF THE DRAWINGS

[0037] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0038] Figure 1 This is a structural block diagram of a satellite firmware upgrade system based on the Android system of the present invention;

[0039] Figure 2 It is a principle flow chart of the satellite firmware upgrade method based on the Android system of the present invention. DETAILED DESCRIPTION

[0040] In order to make the purpose, technical solution and advantages of the embodiments of the present invention clearer, the technical solution in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0041] In one embodiment, referring to Figure 1 As shown, a satellite firmware upgrade system based on the Android system is provided, comprising:

[0042] Android Telephony, which is used to process and manage the communication interactions of wireless electronic communication devices running Android system;

[0043] Framework, which is connected to the Android Telephony through SAT RIL, is the Android system framework layer and is used to provide an application program API interface;

[0044] SAT Modem, integrated with a satellite communication module, connected to the Android Telephony through the Framework, and connected to the satellite module through a UART serial port;

[0045] The SatUpgrader App is respectively connected to the Android Telephony and the SAT Modem for communication, and is provided with a satellite firmware upgrade program for upgrading the satellite module.

[0046] In one embodiment, in the Android Telephony system, the initialization completion broadcast received by the SAT Modem indicates that the satellite communication module has been successfully started and is ready. This process ensures that the device can communicate through the satellite network, thereby providing a reliable connection service for the user. When the satellite communication module is started, it will perform a series of initialization operations to ensure that its functions are functioning normally.

[0047] As a preferred embodiment of the present invention, these operations include but are not limited to establishing a connection with a satellite, calibrating signal strength, configuring necessary communication parameters, etc. Once these steps are completed, the SAT Modem will send a broadcast signal of initialization completion to the Android Telephony system. This signal indicates that the satellite communication module has been fully started and is ready for data transmission and reception. Therefore, users can rely on this process to ensure that their devices can maintain communication connections through satellite networks in the absence of terrestrial network coverage. This reliable connection service is particularly important for users who need to communicate in remote areas or in emergency situations.

[0048] In one embodiment, the SatUpgrader application (App) is not just a simple tool, but a powerful platform that includes a user interface designed specifically for users. The purpose of this user interface is to display and present detailed progress and status information during the satellite firmware upgrade process, allowing users to fully understand the entire upgrade process. Through this interface, users can clearly understand the various stages of the current upgrade, such as initialization, downloading firmware, verifying files, transferring data, and the final completion status.

[0049] To further enhance the user experience, the UI also provides real-time feedback, showing the current progress bar, percentage, and estimated remaining time. This information will help users understand the progress of the upgrade in real time, ensuring that they are always aware of the current upgrade status. During the upgrade process, if any errors or abnormal situations occur, the UI will also display the corresponding error messages or warning prompts in a timely manner. These prompts will help users quickly identify the problem and take appropriate solutions, thereby avoiding any delays or interruptions that may occur during the upgrade process.

[0050] Overall, the SatUpgrader application’s user interface is more than just a presentation tool, it is a comprehensive upgrade management platform that ensures users maintain a high level of control and transparency throughout the upgrade process with detailed status information, real-time feedback, and error notifications.

[0051] In one embodiment, the SatUpgrader application not only provides basic upgrade functions, but also introduces a powerful firmware verification module. The main responsibility of this module is to perform a comprehensive and detailed integrity check on the firmware file to be applied before the firmware upgrade process officially begins. Through this process, it can be ensured that the firmware file has not been tampered with or damaged, thereby ensuring the security and stability of the device during the upgrade process.

[0052] Specifically, the firmware verification module uses a variety of advanced algorithms and technical means to conduct a detailed check on the digital signature, hash value, and other key information of the firmware file to verify its authenticity and integrity. These inspection steps include but are not limited to comparing whether the hash value of the file is consistent with the officially released hash value, verifying whether the digital signature is valid, and checking whether the metadata of the firmware file is complete and correct. Through these strict verification measures, it can be ensured to the greatest extent that the source of the firmware file is reliable and has not been maliciously modified or damaged, thereby providing a solid security guarantee for device upgrades.

[0053] In one embodiment, after receiving the firmware upgrade instruction, the SAT Modem will start a specific upgrade process. First, it will establish a communication connection with the satellite module through the UART serial port. The UART serial port is a commonly used serial communication interface that can ensure stable data transmission. Once the communication connection is successfully established, the SAT Modem will call the satellite firmware upgrade program, which is responsible for handling the entire upgrade process.

[0054] Next, the SAT Modem will transfer the firmware file from the local storage device to the satellite module. This firmware file contains the latest software code and improvements that can enhance the performance and functionality of the satellite module. During the transmission process, the SAT Modem will ensure the integrity and reliability of the data to avoid any transmission errors that may cause the upgrade to fail.

[0055] After the transfer is complete, the SAT Modem will control the satellite module to perform the firmware upgrade operation. This usually involves writing the new firmware to the module's memory and ensuring the normal operation of the module during the upgrade process. The upgrade operation may include restarting the module, verifying the correctness of the firmware, and completing necessary configuration changes. The entire upgrade process will be carried out under the precise control of the SAT Modem to ensure that the upgrade is carried out smoothly and will not affect the normal operation of the satellite module.

[0056] In one embodiment, SAT RIL plays a crucial role in the upgrade process. It is responsible for receiving upgrade instructions from SatUpgrader application and forwarding these instructions to SAT Modem accurately. In addition, SATRIL also undertakes the task of monitoring the upgrade process to ensure that the entire upgrade process proceeds smoothly. During the upgrade process, SAT RIL will collect and record the status information of SAT Modem in real time, including but not limited to the current upgrade progress, system status and any errors or exceptions that may occur.

[0057] As the preferred embodiment of the present invention, these status information are very important to ensure the smooth progress of the upgrade process. Once this information is collected, SAT RIL will immediately report it to the SatUpgrader application so that the application can monitor and manage the entire upgrade process in real time. In this way, SAT RIL ensures the accurate transmission of the upgrade instructions and the timely feedback of the status information, thus playing a key bridge role in the entire upgrade process.

[0058] In one embodiment, Android Telephony is a powerful system component that can help us determine the current working status of the satellite module. Specifically, this component will check whether the satellite module is in an activated state. If the satellite module is found to be in an off state after checking, Android Telephony will automatically take measures to ensure that the satellite module is turned on.

[0059] In this embodiment, once the satellite module is successfully activated, the system will further check whether a firmware upgrade is necessary. If it is detected that the firmware version is outdated or there are potential problems, Android Telephony will notify the SatUpgrader application to start the satellite firmware upgrade procedure. This process ensures that the satellite module always operates in the best state, thereby providing stable and reliable communication services.

[0060] In one embodiment, the present invention provides a satellite firmware upgrade method based on the Android system, comprising the following steps:

[0061] Check whether the satellite module of the wireless electronic communication device is turned on. If it is turned on, wait for its initialization to complete and send a broadcast to Android Telephony;

[0062] Android Telephony detects wireless device broadcasts and checks whether there is a new satellite firmware bin file in the system / etc directory;

[0063] Check for firmware updates. If a new version is found, Android Telephony obtains the current firmware number of the satellite module through the Framework API. If no new version is found, it continues to check.

[0064] Check the satellite module firmware version. If it is lower than the new version, notify to start SatUpgrader App to upgrade, update the firmware through the UART serial port and restart the device. If it is not lower, no action is taken.

[0065] In this embodiment, after the satellite firmware is upgraded, when the device is started for the first time, the Android Telephony system will automatically perform a check to confirm the current status of the satellite module. If it is detected that the satellite module is in a turned-off state, the system will automatically start the module and further check whether there is a need for firmware upgrade. Once a need for firmware upgrade is found, the system will immediately start the SatUpgrader application to perform the necessary firmware upgrade operations.

[0066] During a device reboot, the situation is slightly different. If the satellite module is off when it reboots, the system will not take any action. However, if the satellite module is already on, the Telephony application will check again after the satellite module has completed initialization to confirm whether there is a need for a firmware upgrade. If a firmware upgrade is detected, the system will launch the SatUpgrader application again to ensure that the satellite module firmware can be updated to the latest version in a timely manner.

[0067] In this embodiment, when the user manually activates the satellite module, the device will automatically enter the initialization state, and after receiving the signal that the initialization is completed, the system will immediately check to determine whether a firmware upgrade is necessary. If the detection result shows that a firmware upgrade is required, the control module will start the SatUpgrader application, and then start the entire upgrade process to ensure that the firmware of the satellite module is kept up to date to provide optimal performance and functionality.

[0068] In summary, based on the existing Android system, the present invention has carefully designed and developed three main modules: Framework API, Telephony application and SatUpgrader App. These modules each have different functional responsibilities, making the design of the entire system more reasonable and the process clearer. This innovative design method enables the present invention to be widely used in various satellite mobile phone devices based on the Android system.

[0069] First, the Framework API module, as the core of the entire system, is responsible for providing the underlying interface support to ensure that other modules can interact smoothly with the Android system. Secondly, the Telephony application module focuses on processing telephone functions related to satellite communications, allowing users to enjoy a more stable and efficient communication experience when using satellite phones. Finally, the SatUpgrader App module is mainly responsible for upgrading the satellite firmware, ensuring that the satellite module in the user's mobile phone can receive the latest firmware updates in a timely manner.

[0070] During the design process, the present invention fully considers various scenarios of satellite firmware upgrades, including but not limited to online upgrades, offline upgrades, and emergency upgrades. Through comprehensive consideration of these scenarios, the present invention can ensure that the satellite firmware can be quickly and accurately transmitted to the user's satellite mobile phone module after the update. In this way, users do not need to worry about functional problems caused by the long-term non-update of satellite firmware, thereby greatly improving the user experience and the reliability of the device.

[0071] The above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit the same. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that the technical solutions described in the aforementioned embodiments may still be modified, or some of the technical features may be replaced by equivalents. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A satellite firmware upgrade system based on Android system, characterized in that: include: Android Telephony, which is used to process and manage the communication interactions of wireless electronic communication devices running Android system; Framework, which is connected to the Android Telephony through SAT RIL, is the Android system framework layer and is used to provide an application program API interface; SAT Modem, integrated with a satellite communication module, connected to the Android Telephony through the Framework, and connected to the satellite module through a UART serial port; The SatUpgrader App is respectively connected to the Android Telephony and the SAT Modem for communication, and is provided with a satellite firmware upgrade program for upgrading the satellite module.

2. The satellite firmware upgrade system based on the Android system according to claim 1, characterized in that: The Android Telephony receives the broadcast of satellite module initialization completion through the SAT Modem.

3. The satellite firmware upgrade system based on the Android system according to claim 1, characterized in that: The SatUpgrader App includes a user interface for displaying satellite firmware upgrade progress and status information.

4. The satellite firmware upgrade system based on the Android system according to claim 1, characterized in that: The SatUpgrader App also includes a firmware verification module for performing integrity verification on the firmware file before upgrading.

5. The satellite firmware upgrade system based on Android system according to claim 1, characterized in that: After receiving the firmware upgrade instruction, the SATModem communicates with the satellite module through the UART serial port, transfers the firmware file to the satellite module through the satellite firmware upgrade program, and controls the satellite module to perform the firmware upgrade operation.

6. The satellite firmware upgrade system based on Android system according to claim 1, characterized in that: The SATRIL is responsible for forwarding the upgrade instruction from the SatUpgrader App to the SAT Modem during the upgrade process, and reporting the status information of the upgrade process to the SatUpgrader App.

7. The satellite firmware upgrade system based on Android system according to claim 1, characterized in that: The Android Telephony is used to determine whether the satellite module is turned on. If the satellite module is turned off, the satellite module is automatically turned on to check whether the firmware needs to be upgraded. If the firmware needs to be upgraded, the SatUpgrader App is notified to start the satellite firmware upgrade program.

8. A satellite firmware upgrade method based on the Android system, the method using the satellite firmware upgrade system based on the Android system as claimed in any one of claims 1 to 7, characterized in that: The following steps are involved: Check whether the satellite module of the wireless electronic communication device is turned on. If it is turned on, wait for its initialization to complete and send a broadcast to Android Telephony; Android Telephony detects wireless device broadcasts and checks whether there is a new satellite firmware bin file in the system / etc directory; Check for firmware updates. If a new version is found, Android Telephony obtains the current firmware number of the satellite module through the Framework API. If no new version is found, it continues to check. Check the satellite module firmware version. If it is lower than the new version, notify to start SatUpgrader App to upgrade, update the firmware through the UART serial port and restart the device. If it is not lower, no action is taken.

9. The method for upgrading satellite firmware based on Android system according to claim 8, characterized in that: In the method, after the satellite firmware is upgraded, Android Telephony will check the status of the satellite module when it is turned on for the first time. If the module is turned off, it will automatically turn on and check the firmware upgrade requirement. If there is a firmware upgrade requirement, it will control the SatUpgrader App to perform the upgrade; During restart, if the satellite module is turned off, no action will be taken; if it is turned on, the Telephony app will check for firmware upgrade requirements after the satellite module is initialized. If there is a firmware upgrade requirement, it will control the SatUpgrader App to perform the upgrade.

10. The method for upgrading satellite firmware based on Android system according to claim 8, characterized in that: In the method, after the user manually turns on the satellite module, after recognizing and receiving the initialization completion signal, it is checked whether a firmware upgrade is required. If necessary, the SatUpgrader App is controlled to start the upgrade program.

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