Embedded linux is an operating system that tailors the increasingly popular Linux operating system so that it can run on an embedded computer system. Embedded Linux not only inherits the unlimited open source code resources on the Internet, but also has the characteristics of an embedded operating system. Embedded Linux is characterized by free copyright fees; purchase costs, media costs, technical support, free software developers around the world, and support. Network features are free, with excellent performance, easy software transplantation, open code, support for many application software, and application product development cycle Short, new products are launched quickly, because there are many open codes that can be referenced and transplanted, real-time performance RT_Linux Hardhat Linux and other embedded Linux support, real-time performance stability is good and security is good.
First of all, the source code of its kernel is open, and many technical questions can be answered on the embedded LINUX website. The support is very good, and at the same time, it can save the cost of buying other operating system source code and corresponding support costs; secondly, the LINUX operating system It is easier to master with the compiler, and has better support for standard C, which saves the time spent on familiarizing the operating system and compiling; finally, through the development of the LINUX system, it is easy to develop products belonging to your own platform in the future, in terms of security Improved to avoid the problem of backdoors left in many operating systems.
2. Description of program operation using LINUX platform.After the CPU is powered on or reset, a bootloader is required to boot the system, and then the system loads the GUI graphical interface. At this time, we can use the touch screen, soft keyboard, keyboard (custom or standard PS/2) Interact with the handheld computer in order to run our own programs and observe the results of the operation on the LCD.
3. Measures to be taken to solve the problems that need to be solved by adopting this scheme.1. The bootloader, because it is directly related to the boot of the system kernel, is an important part of the system. (Because the source code of the bootloader has not yet been disclosed, the foreign lineo company has already solidified the bootloader on the board when it provides the development board. After the delivery of the bootloader, foreign LINEO will receive lincnes. Because of the special status of the bootloader, in the domestic development board level, no company has publicly released a development system that can provide VZ embedded LINUX. But fortunately Yes, our studio has developed its own bootloader program. With bootloaer, you can interact with the development board without entering the operating system on the board, such as online burning, memory modification, program download, etc. And the domestic Huaheng company There is no bootloader that needs to process the development board after entering the operating system.
2. To support VZ by the compiler and LINUX system, you need to purchase a development kit that can support VZ328. The most important thing is a patch in this kit, which can make the compiler successfully compile VZ328. The operating system and compiler downloaded from the Internet can only support the compilation of EZ328, which is the set of Huaheng.
3. The purchase of GUI interface, touch screen, soft keyboard driver and other human-computer interaction programs. Because of this, it plays a vital role in the development progress and performance of the system. If time allows for self-development, it will be very difficult to do so. You can also consider buying from a third party. Of course, we have already finished some of them outside the workshop.
Fourth, the situation of third parties that can provide our embedded LINUX system support1. The company
a. Beijing Co-Creation Open Source Software Company, which has a mature LINUX system GUI solution for embedding ARM, but has no mature solution for DragONBall system, mainly refers to its GUI part. But the price will be very expensive.
b. Huaheng Technology Network Co., Ltd. of the University of Science and Technology of China in Hefei can provide EZ development boards and corresponding LINUX kits, but it has not yet been released for VZ.
c. Foreign Lineo company provides a full set of development support for LINUX system, including development board and development compilation system. The price of development board is 775 US dollars. A key development kit PRE10 may cost 495 US dollars, totaling 1270 US dollars. English support is good, but local support is not good enough. Only Japan and Taiwan have offices in Asia.
Five, the current development of domestic LINUX embedded operating systemIn China, embedded operating systems can be divided into two types: one is an operating system with independent copyright, and the other is an operating system based on Linux. In recent years, embedded Linux has made rapid progress. In China, Linux-based embedded operating systems are relatively active, among which Chinasoft Linux, Red Flag Linux, and Eastern Linux are the representatives of the industry. Based on the CNC platform, Chinasoft Corporation launched Chinasoft Linux3.0. Chinasoft Embedded Linux is a real-time system. This Linux-based embedded system not only meets the needs of CNC machine tools, but also can be applied to other industrial control areas. Red Flag Linux regards industrial control and information appliances as its primary development category. Red Flag Linux provides users with Windows-style control sets, graphical Chinese environment and embedded database development tools. Zhongke Hongqi has developed an embedded Linux system for industrial control. Eastern Linux is a product launched by Keith Group. Through cooperation with SMIC, Kai Si Road has launched a network computer (NC). In addition to the traditional final functions, the NC series products using Eastern Linux also have local computing capabilities. Users can use the applications installed on the server through the NC and use a variety of local software. The working method of this product is based on the computing standard style of centralized and open network services, and is compatible with multiple network protocol standards. Users can pass through the network connection equipment at any place and visit the server in real time. The product can be used in government, national defense, education, commerce, finance and other fields.
Attachment: DragonBall 68VZ328 processor based on Motorola's 68K architecture
1. Application introduction:
The DragonBall series is a quasi-32-bit embedded CPU. Because of its low price and powerful functions, it is adopted by many PDA manufacturers. Businesslink, Autotoll, Celebrities, and Aurora all have their own PDAs with their CPUs. The essence should be Motorola. The Baodian 828 was made at the same time when the DragonBall CPU system was launched. However, the RF part adopts the FLAX protocol. The nationwide wireless seeks to unify the frequency point without pushing it. The next step is to give up your handwriting pen and search. Calling the market, of course, it gave up the PDA market and became a provider of PDA solutions. However, the profit of the guitar provided by the chip is much easier and better than that of the PDA.
In addition to being mainly used for PDAs, the DragonBall CPU can also be used on some handheld terminals, such as POS and data acquisition terminals. It can also be used on fixed terminals, such as cash registers, ticket collectors, medical equipment, and computer phones. It can also be used on e-books and MP3 master CPUs.
This CPU will occupy a large area of ​​the market with an absolute advantage in the next few years, and its potential will be close to 51. Therefore, many companies are preparing to develop their products. Of course, several companies are developing their embedded LINUX operating system. Heng Studio is also a company, but not a company. It is a team of students. LINUX has successfully run, GUI and some applications have been completed. The last job is to cooperate with the company to create a brand.
2. Supported operating systems:
2.1 Motorola PPSM real-time single-task operating system.
2.2 ATI Nuclues real-time multitasking operating system.
2.3 Microsoft WindowsCE operating system.
2.4 Linux
2.5 PalmOS
3. Main processor features:
3.1 Based on FLX68K core.
3.2 Peripheral chip selection logic and bus interface, addressing space up to 4G.
3.3 Clock generation mode and power control.
3.4 76 parallel general purpose I/O ports.
3.5 Two pulse width regulators, and one PWM output.
3.6 Two general purpose timers.
3.7 Two serial SPI.
3.8 Two UART and infrared interface support.
3.9 Internal LCD controller, support STN color and monochrome, resolution up to 640*512.
3.10 The real-time clock can count up to 512 days.
3.11 Internal WatchDog
3.12 DRAM controller supports EDO and SDRAM.
3.13 ICE simulation mode support.
3.14 Bootstrap mode support.
3.15 External clock 32.768KHz, internal 33MHz, 5.4MIPS.
3.16 9 interrupt input ports, 7-level interrupt, 4 can be dedicated to keyboard interrupt.
3.17 The processor performance and speed are more than twice as high as EZ328.
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