| The content recommended of this paper is how to apply embedded Linux to the GPS trade terminal device.The so-called GPS trade terminal, can describe as GPS +PDA + cell-phone simply as for the function. That is to say that such a system contains a set of intact GPS user's acception systems functionally in GPS, hardware already include GPS satellite data receive module, software include GPS data processing software. And this terminal device also includes the function of PDA and cell- phone besides GPS function, can say so , the GPS trade terminal of this project is a SmartPhone products with GPS function . And what this paper discussed is to use embedded Linux system to realize the all function on this GPS trade terminal device .In the field of embedded cell-phone operating system, Palm OS , Symbian , Pocket PC are three major operating systems occupying the nearly all market, now relying on the remarkable behavior in embedded respect Linux have ability to join the contention among the cell-phone operating systems. From the view of application development, for the source code of Linux is open, Linux can help the independent software developer to develop application software with high efficiently utilization of hardware and better function, and help trade users develop one's own security , controlled authentication system too. Especially while a large number of PDA cell-phones is used as trade application portable terminals , using Linux can implement security tactics of system integration easily. All sorts of advantages of Linux indicate that it must become a dark horse on the operating system of the cell-phone .Though embedded Linux operating system has a lot of advantages , it is still a new subject to apply to the GPS trade terminal device, face a great deal of challenges. This paper has carried on detailed analysis on the technology that embedded Linux applied to the GPS trade terminal device and the question may meet , and has put forward the method to solve to the technological difficult problem . The GPS trade terminal described of this paper is a actual project that author participates in, the microprocessor adopted is Motorola MX1 processor. Because Motorola MX1 processor builds up besed on ARM, so we need to establish the cross development environment based on ARM to carry on Linux embedded development. The ARM cross development environment is made up with a suit of components for compiling , assembling ,linking kernel and application program. These components include: Binutils ,Gcc ,Glibc .The cross compiler Set up by above-mentioned components is run at x86 processor ,but can compile commands of ARM processor. And then, we can enter development of the whole embedded Linux system , applying embedded Linux operating system to above-mentioned trade terminal device need to solve some difficult problems, including develop bootloader program, cut down and customize the kernel, develop the driver, combine GUI procedure and develop the necessary application program, build up file system ,etc.. Now we will do the simple introduction to each question.The kernel is a core of an operating system, it is responsible for management process, memory, device driver, file and network of the system,and determines systematic performance and stability. According to kernel configuration principle and GPS trade terminal project's actual demand,we carry on effective reduction to kernel function and components.Using arm-linux-gcc compiler we can compile embedded Linux kernel running in arm environment.In the embedded system,BootLoader is a little similar to BIOS acting on on PC, it initialezes the main part on the board like CPU, SDRAM, FLASH, Serial port etc.. BootLoader is all used for Linux based on arm devices.While BootLoader is installed to flash memory, it will carry out the above-mentioned initializing works. Then, it plans to receive the kernel and file system from host computer. Once pack kernel into, BootLoader will give kernel the control right. The GPS trade terminal system in the paper adopts B...
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