The Research And Development Of GPRS DTU Based On ARM

Nowadays, embedded systems are one of the most popular research fields and will be the most promising direction of the Post-PC Era. It's widely used in Information Appliances (IA), hand-held communications equipment, instrumentation, automotive, aerospace, industrial control, data acquisition and so on. It has brought great convenience for people to work and live.GPRS DTU is an important application of embedded systems in the fields of industrial control and data acquisition. Its function is to transmiss serial data through GPRS network and to provide a wireless back up link. Therefore it improves the reliability of data transmission. With the growing demand for intelligence, the concept of intelligent GPRS DTU is put forward. In addition to the original basic functions, more intelligent modules need to be provided, such as maintaining a permanent on-line by automatic heartbeat, remote access, web remote management, automatic updates and so on. It could save the cost of maintenance and is more cost-effective and therefore the research on intelligent GPRS DTU has broad sense and good business prospects.This paper is aimed to design and implement GPRS DTU intelligent application platform and to deeply analyze the key technology on intelligent functions. First of all, the basic concept and design process of embedded systems are introduced based on the theoretical level, and some methods are summed up, such as seizing the essence, hierarchical integration, coordination division, scene analysis and so on; second, introduce GPRS DTU hardware platform, which adopts ATMEL's AT91RM9200 as core control unit and Telit's GM862 as GPRS module in order to achieve industrial-level requirement; third, sum up the method to convert Linux ELF format file to a binary file, and then focus on correcting U-boot's unreasonable application on AT91RM9200's remap mechanism and realizing the independence of U-boot's boot mode; fourth, an embedded hybrid filesystem (Cramfs+JFFS2+Initramfs) for intelligent GPRS DTU design scheme is proposed, which is a key module of intelligent GPRS DTU. Meanwhile, port and customize Linux-2.6.20 kernel based on the needs of EFS and applications; finally, illustrate the basic theorial model of application development using design scheme of serial/Ethernet data gateway.The key technology on research and development of the GPRS DTU intelligent platform has got good results and gives a strong technical support for intelligent GPRS DTU.