Application design of military PDA based on SHARP LH7A400 processor

With the informatization and electronicization of modern warfare, handheld smart devices (military PDAs) with diverse functions but also exquisite and practical are increasingly being valued by the military. Because military PDAs need to integrate satellite positioning, wireless communication, image capture and transmission, and other functions, they are essential for combat entities in high-tech warfare. Some foreign countries have long been engaged in the research and development of related technologies, and such products Equipped to specific combat situations.

Author: Tan Yong

With the informatization and electronicization of modern warfare, handheld smart devices (military PDAs) with diverse functions but also exquisite and practical are increasingly being valued by the military. Because military PDAs need to integrate satellite positioning, wireless communication, image capture and transmission, and other functions, they are essential for combat entities in high-tech warfare. Some foreign countries have long been engaged in the research and development of related technologies, and such products Equipped to specific combat situations. Military PDA products[/I]have different functional requirements according to different applications, involving a variety of current most advanced technologies, such as embedded CPU applications, multi-task operating system RTOS, GIS applications, satellite positioning system positioning, wireless communication , Bluetooth technology, CCD technology, image processing technology, etc. This article combines a general-purpose 32-bit CPU to illustrate the composition and implementation of a military PDA.

1. Hardware implementation:

According to the characteristics of high-tech combat of the modern military, the PDA we designed for the military should meet the special requirements of the military. First of all, in terms of function, it should have strong real-time, stable positioning function, clear image processing and transmission, wireless communication, etc. In this way, our hardware composition is basically determined.

Application design of military PDA based on SHARP LH7A400 processor

1.1. Introduction to CPU:

・ Three serial ports, synchronous serial port (SSP), one IrDA infrared port
・ PCMCIA/CF controller
・ AC97 Codec interface controller
・ Programmable LCD controller
・ USB controller
・ SMART CARD interface
・ MultiMediaCard interface
・ 60 general programmable ports
・ JTAG programming interface
・ Three serial ports
· Real Time Clock
・ Watchdog clock

1.2. Power planning:

A considerable part of the use environment of military PDAs is in the field, and the working environment in the field is unable to charge PDA devices regularly, but our peripherals are very large and the current consumption is very large. In this way, there is a very prominent contradiction. Therefore, we have to plan very carefully in the circuit design.

First of all, we use large-capacity lithium batteries here, such as 1000mAh or even larger. Secondly, we use a large number of LDOs here to subdivide each power consumption link as much as possible to achieve independent power supply or combined power supply to control the start and stop of the equipment. Once again, we need to provide independent power supply for high-current equipment. We not only need to ensure the stable power demand of the system, but also the large current consumption of modules such as GPRS. Finally, pay special attention to the problem of power shock when the power of a certain module is started. If you do not give enough knowledge, it will cause system instability or even crash.

Application design of military PDA based on SHARP LH7A400 processor

1.3. CCD interface:

CCD image technology can be used in specific occasions, such as reconnaissance, detection, etc., with the help of the storage, processing and transmission functions of military PDAs to achieve corresponding military purposes. Here we use CMOS with 300,000 pixels or even higher resolution to meet our needs. At the same time, for the real-time requirements of the system, we have to add a FIFO to buffer the image data to avoid data loss.

1.4. USB communication interface:

Through the USB interface, we can transmit many important information that needs to be stored and analyzed, such as image data, satellite positioning system channel information, and so ON. The USB1.1 interface is sufficient to meet most data communication needs. The CPU we used here includes a USB Device interface, and the need for data serial communication can be achieved by controlling specific registers and writing software.

Application design of military PDA based on SHARP LH7A400 processor

1.5. Satellite positioning system positioning system:

Satellite Positioning System (GPS) is a very important basic part of PDA, and its role in war is obvious to all. In addition to missile guidance and other functions, in military PDA products, in conjunction with military maps, satellite positioning system technology allows each combat entity to accurately determine their position, providing guarantees for the assembly of troops under special terrain or the march of specific purposes.

GIS (Geographic Information System) is an important application of military PDA. It usually embeds a specific military Electronic map into the PDA, which can be zoomed, rotated, and dragged, and can be used as a platform to identify the precise geographic location of combat individuals at any time.

In order to realize the modular design idea, we can use the satellite positioning system module to replace the integrated design of separate components. The communication between the module and the CPU is simply realized through a specific serial communication port.

Application design of military PDA based on SHARP LH7A400 processor

1.6. Wireless communication:

The use of wireless communication technology in military PDAs enables various combat entities to communicate with each other and maintain contact with the command center. Civil related products can use GSM or CDMA technology, but for military use, other methods or special encryption must be used. We can see how important wireless voice technology is, so it is an indispensable important component. Here we use industrial or military grade GSM modules to meet specific needs.

1.7. Infrared interface:

Infrared serial communication interface is a common way of short-distance communication. Because of its convenience and practicality, most palm devices have infrared interfaces. SHARP7A400 integrates an infrared serial high-speed interface controller, so it only needs to be electrically connected to send and receive infrared data.

Application design of military PDA based on SHARP LH7A400 processor

2. Software Implementation:

Because the data recorded in the field is often non-repeatable, we must fully consider the importance of data backup in terms of software. At the same time, the system must have a variety of self-protection functions, such as automatic restart after crash, to maintain high stability. Around the CPU, there must be a layer of operating system, file system, graphics system, etc., as well as corresponding network software protocols to handle communications. On this basis, build upper-level application software.

Therefore, we must consider the above factors when choosing an operating system. The currently popular WINCE and Nucleus real-time systems are all relatively stable operating systems. This choice is based on different priorities. At the same time, write the relevant BSP package on the application software according to the specific hardware structure.

Under normal circumstances, our software should meet the following main functions. The whole system consists of five parts:

1. Sub-system: Using 100MHZ high-speed ARM9 processor, 64M memory, 32M FLASH memory. Built-in lithium battery power supply system, rechargeable, continuous working for 10 hours, standby for 1 week.

2. Communication subsystem: including communication circuit, GSM module and infrared module. Support HCI, L2CAP protocol, can carry out data transmission and reception and UART connection. Be able to surf the Internet (data service), send and receive e-mails, and send and receive short messages.

3. Positioning sub-system: using the combination of GIS and satellite positioning system, the electronic map can be zoomed 64 times, positioning and tracking through coordinates, and the map can be dragged with the touch Screen.

4. Image subsystem: Obtain and process image information.

5. Software subsystem: the underlying software platform is a full set of real-time multitasking operating system (RTOS) with independent intellectual property rights, including scheduling kernel (KERNEL), graphics software package (GRAFIX), file system (FILE) and TCP/IP software package, etc. . The driver software includes touch screen driver, keyboard driver, serial port driver, infrared driver, GSM driver, satellite positioning system driver and CCD driver. The upper application software includes electronic map, satellite positioning system application package, e-mail, digital image processing package, GSM short message sending and receiving package, notepad, clock, calculator, address book, paint brush, etc.

3. Structural design:

According to military PDAs, they often work in harsh outdoor environments. Low temperature, rain and snow, strong electromagnetic interference, mechanical shock, etc. are all great tests for PDA. In this way, we must consider how to ensure that the PDA still works stably under such conditions. Circuit boards, connecting wires, fixing screws, housings, etc. must be treated with special treatment.

The circuit board is the main carrier of the electrical part. First of all, the above comprehensive factors should be considered in the process of drawing the circuit board. The multi-layer circuit board structure is adopted, and the surface layer is not routed as much as possible, so that EMC protection is effectively carried out. At the same time, the circuit board after welding and debugging should be treated with three preventions. In this way, the surface of the circuit board is well protected.

The connecting wire is an indispensable part of the body. It is best to use waterproof treatment and reinforcement treatment at the interface, so that it can resist mechanical shock and rain.

The fixing screws must be non-slip fastening screws, and the pads must be non-slip pads. At the same time, it must be glued after installation. Such processing of general mechanical vibration will not damage the fastening relationship of the PDA.

The shell is the most important protection measure for the PDA. Here we use all aluminum alloy to make the shell. This structure changes the shortcomings of the plastic housing that cannot withstand mechanical shocks. It also provides good EMC protection. In addition, his weight is relatively light and easy to carry.

Structural protection measures are not limited to these. Some of the above measures can basically meet the protection needs of the complex environment in the wild.

4. Concluding remarks:

With the continuous development of technology, military-grade PDAs have broad development prospects. According to its technical performance and characteristics, the PDA solution can be widely used in the following fields:

1. Military/police: Because of its GIS system, satellite positioning system and flexible communication methods, it can be effectively applied to individual combat systems, liaison command systems, patrol and pursuit systems, etc.
2. Aviation: dispatch command system
3. Medical: Robotic medical control system
4. Railway: Dispatching Command System
5. Industrial control: data acquisition systems for firefighting, electric power, etc.
6. General PDA with email and Internet functions

Author: Tan Yong

With the informatization and electronicization of modern warfare, handheld smart devices (military PDAs) with diverse functions but also exquisite and practical are increasingly being valued by the military. Because military PDAs need to integrate satellite positioning, wireless communication, image capture and transmission, and other functions, they are essential for combat entities in high-tech warfare. Some foreign countries have long been engaged in the research and development of related technologies, and such products Equipped to specific combat situations. Military PDA products[/I]have different functional requirements according to different applications, involving a variety of current most advanced technologies, such as embedded CPU applications, multi-task operating system RTOS, GIS applications, satellite positioning system positioning, wireless communication , Bluetooth technology, CCD technology, image processing technology, etc. This article combines a general-purpose 32-bit CPU to illustrate the composition and implementation of a military PDA.

1. Hardware implementation:

According to the characteristics of high-tech combat of the modern military, the PDA we designed for the military should meet the special requirements of the military. First of all, in terms of function, it should have strong real-time, stable positioning function, clear image processing and transmission, wireless communication, etc. In this way, our hardware composition is basically determined.

Application design of military PDA based on SHARP LH7A400 processor

1.1. Introduction to CPU:

・ Three serial ports, synchronous serial port (SSP), one IrDA infrared port
・ PCMCIA/CF controller
・ AC97 Codec interface controller
・ Programmable LCD controller
・ USB controller
・ SMART CARD interface
・ MultiMediaCard interface
・ 60 general programmable ports
・ JTAG programming interface
・ Three serial ports
· Real Time Clock
・ Watchdog clock

1.2. Power planning:

A considerable part of the use environment of military PDAs is in the field, and the working environment in the field is unable to charge PDA devices regularly, but our peripherals are very large and the current consumption is very large. In this way, there is a very prominent contradiction. Therefore, we have to plan very carefully in the circuit design.

First of all, we use large-capacity lithium batteries here, such as 1000mAh or even larger. Secondly, we use a large number of LDOs here to subdivide each power consumption link as much as possible to achieve independent power supply or combined power supply to control the start and stop of the equipment. Once again, we need to provide independent power supply for high-current equipment. We not only need to ensure the stable power demand of the system, but also the large current consumption of modules such as GPRS. Finally, pay special attention to the problem of power shock when the power of a certain module is started. If you do not give enough knowledge, it will cause system instability or even crash.

Application design of military PDA based on SHARP LH7A400 processor

1.3. CCD interface:

CCD image technology can be used in specific occasions, such as reconnaissance, detection, etc., with the help of the storage, processing and transmission functions of military PDAs to achieve corresponding military purposes. Here we use CMOS with 300,000 pixels or even higher resolution to meet our needs. At the same time, for the real-time requirements of the system, we have to add a FIFO to buffer the image data to avoid data loss.

1.4. USB communication interface:

Through the USB interface, we can transmit many important information that needs to be stored and analyzed, such as image data, satellite positioning system channel information, and so on. The USB1.1 interface is sufficient to meet most data communication needs. The CPU we used here includes a USB Device interface, and the need for data serial communication can be achieved by controlling specific registers and writing software.

Application design of military PDA based on SHARP LH7A400 processor

1.5. Satellite positioning system positioning system:

Satellite Positioning System (GPS) is a very important basic part of PDA, and its role in war is obvious to all. In addition to missile guidance and other functions, in military PDA products, in conjunction with military maps, satellite positioning system technology allows each combat entity to accurately determine their position, providing guarantees for the assembly of troops under special terrain or the march of specific purposes.

GIS (Geographic Information System) is an important application of military PDA. It usually embeds a specific military electronic map into the PDA, which can be zoomed, rotated, and dragged, and can be used as a platform to identify the precise geographic location of combat individuals at any time.

In order to realize the modular design idea, we can use the satellite positioning system module to replace the integrated design of separate components. The communication between the module and the CPU is simply realized through a specific serial communication port.

Application design of military PDA based on SHARP LH7A400 processor

1.6. Wireless communication:

The use of wireless communication technology in military PDAs enables various combat entities to communicate with each other and maintain contact with the command center. Civil related products can use GSM or CDMA technology, but for military use, other methods or special encryption must be used. We can see how important wireless voice technology is, so it is an indispensable important component. Here we use industrial or military grade GSM modules to meet specific needs.

1.7. Infrared interface:

Infrared serial communication interface is a common way of short-distance communication. Because of its convenience and practicality, most palm devices have infrared interfaces. SHARP7A400 integrates an infrared serial high-speed interface controller, so it only needs to be electrically connected to send and receive infrared data.

Application design of military PDA based on SHARP LH7A400 processor

2. Software Implementation:

Because the data recorded in the field is often non-repeatable, we must fully consider the importance of data backup in terms of software. At the same time, the system must have a variety of self-protection functions, such as automatic restart after crash, to maintain high stability. Around the CPU, there must be a layer of operating system, file system, graphics system, etc., as well as corresponding network software protocols to handle communications. On this basis, build upper-level application software.

Therefore, we must consider the above factors when choosing an operating system. The currently popular WINCE and Nucleus real-time systems are all relatively stable operating systems. This choice is based on different priorities. At the same time, write the relevant BSP package on the application software according to the specific hardware structure.

Under normal circumstances, our software should meet the following main functions. The whole system consists of five parts:

1. Sub-system: Using 100MHZ high-speed ARM9 processor, 64M memory, 32M FLASH memory. Built-in lithium battery power supply system, rechargeable, continuous working for 10 hours, standby for 1 week.

2. Communication subsystem: including communication circuit, GSM module and infrared module. Support HCI, L2CAP protocol, can carry out data transmission and reception and UART connection. Be able to surf the Internet (data service), send and receive e-mails, and send and receive short messages.

3. Positioning sub-system: using the combination of GIS and satellite positioning system, the electronic map can be zoomed 64 times, positioning and tracking through coordinates, and the map can be dragged with the touch screen.

4. Image subsystem: Obtain and process image information.

5. Software subsystem: the underlying software platform is a full set of real-time multitasking operating system (RTOS) with independent intellectual property rights, including scheduling kernel (KERNEL), graphics software package (GRAFIX), file system (FILE) and TCP/IP software package, etc. . The driver software includes touch screen driver, keyboard driver, serial port driver, infrared driver, GSM driver, satellite positioning system driver and CCD driver. The upper application software includes electronic map, satellite positioning system application package, e-mail, digital image processing package, GSM short message sending and receiving package, notepad, clock, calculator, address book, paint brush, etc.

3. Structural design:

According to military PDAs, they often work in harsh outdoor environments. Low temperature, rain and snow, strong electromagnetic interference, mechanical shock, etc. are all great tests for PDA. In this way, we must consider how to ensure that the PDA still works stably under such conditions. Circuit boards, connecting wires, fixing screws, housings, etc. must be treated with special treatment.

The circuit board is the main carrier of the electrical part. First of all, the above comprehensive factors should be considered in the process of drawing the circuit board. The multi-layer circuit board structure is adopted, and the surface layer is not routed as much as possible, so that EMC protection is effectively carried out. At the same time, the circuit board after welding and debugging should be treated with three preventions. In this way, the surface of the circuit board is well protected.

The connecting wire is an indispensable part of the body. It is best to use waterproof treatment and reinforcement treatment at the interface, so that it can resist mechanical shock and rain.

The fixing screws must be non-slip fastening screws, and the pads must be non-slip pads. At the same time, it must be glued after installation. Such processing of general mechanical vibration will not damage the fastening relationship of the PDA.

The shell is the most important protection measure for the PDA. Here we use all aluminum alloy to make the shell. This structure changes the shortcomings of the plastic housing that cannot withstand mechanical shocks. It also provides good EMC protection. In addition, his weight is relatively light and easy to carry.

Structural protection measures are not limited to these. Some of the above measures can basically meet the protection needs of the complex environment in the wild.

4. Concluding remarks:

With the continuous development of technology, military-grade PDAs have broad development prospects. According to its technical performance and characteristics, the PDA solution can be widely used in the following fields:

1. Military/police: Because of its GIS system, satellite positioning system and flexible communication methods, it can be effectively applied to individual combat systems, liaison command systems, patrol and pursuit systems, etc.
2. Aviation: dispatch command system
3. Medical: Robotic medical control system
4. Railway: Dispatching Command System
5. Industrial control: data acquisition systems for firefighting, electric power, etc.
6. General PDA with email and Internet functions

The Links:   NL2432HC22-30B 1DI300M-120