Technology Of The Application Of Handheld RFID Reader For Embedded Linux Porting

Along with the rapid development of computer technology, microprocessor technology and radio frequency identification (RFID) technology, the application of handheld RFID reader oriented research in the development of embedded system becomes to be the present hot spot of research. The Linux system, which is characterized with the features of powerful functions, open source, scalable, etc, becomes the first choice of embedded operating system by porting. However, there are two essential issues on the application of handheld RFID reader oriented research which is based on Linux system in the development of embedded system: First, when tailoring the Linux kernel for the embedded system, because of the problems of oversize granularity and small precision, the existing tailoring methods cannot satisfy the handheld RFID reader's needs for smaller kernel volume. Second, the existing real-time scheduling algorithm for Linux system is unable to satisfy the handheld RFID reader's requests to higher real-time performance. Therefore, this article is carried out mainly on following aspects:In view of the tailoring methods for Linux kernel cannot meet the smaller kernel volume's requirements for the applications of handheld RFID reader, a kind of embedded Linux kernel mixed tailoring method is proposed. Based on the code analysis tailoring method and the advantage of the call graph tailoring method, this method utilizes the configuration tailoring method by synthesis, and tailors the embedded Linux kernel's scalable items of the application of handheld RFID reader oriented research, and a smaller size granularity and higher precision kernel image is obtained. The test and the results indicate that, the tailoring rate of this method is promoted more than 24% comparing with the configuration tailoring method.In view of the Linux system real-time performance cannot meet the higher real-time performance's requirements for the applications of handheld RFID reader, a kind of real-time task classification scheduling algorithm is proposed. This algorithm is classified into periodic tasks and the non-periodic tasks according to the arrival situation, and uses different improvement real-time scheduling algorithm to schedule different types of real-time task, reduces the system's scheduling delays and deadlines miss rate. The test and the results indicate that, compared with Earliest Deadline First (EDF) and Rate-Monotonic (RM) algorithm, the integrated real-time performance of embedded Linux system gets 10% - 20% improvement by using this algorithm.At the end of this paper, on the ARM (Advanced RISC Machines) Corporation's S3C2410 platform, we have realized the embedded Linux system porting for the applications of handheld RFID reader, and use the source software SkyEye to confirm the porting results. The results show that the above Linux kernel mixed tailoring method and the real-time task classification scheduling algorithm are correct and effective, the ported embedded Linux system can be successfully and reliably operated.