Design And Realization Of Learning Machine Based On Cortex-M3and μC/OS-Ⅱ Operating System

Electronic dictionary learning machine came out in the late1940s, but it developed veryslowly in the beginning because of the limitations of the development of electronictechnology, until the1980s. Compared with traditional paper dictionary, it's easy to carry,function-rich, etc. Rapidly it becomes the mainstream tool for learning. For now, the researchand development of electronic dictionary learning machine has reached an unprecedentedperiod of prosperity.The contents of this paper are jointly developed with enterprise, which aims to design akind of fully functional, stable performance, market-oriented learning machine. It designsand implements a learning machine based on the electronic dictionary from both hardwareand software aspects,and the USB communication capabilities between learning machineand PC will be realized.At the hardware aspect, the system uses LM3S6911as the interface controller, uses thekeyboard input and LCD display output as the man-machine interface. The vocabulary of theelectronic dictionary is up to457525, corresponding thesaurus data and word pronunciationdata size is about60M, the size of its corresponding thesaurus data and pronouncing words isabout60M, therefore, it chooses the SD card as the storage device for storing thesaurus andword pronunciation data, etc. Meanwhile, in order to facilitate the user to restore andupgrade the thesaurus and add their interest learning materials, the system achieves thecommunication with PC end of the USB by using the USB interface chip PDIUSBD12. Thepronunciation of the word in the system is in MP3format audio data, uses the MP3decoderchip VS1003to decode and playback the MP3.At the software aspect, first of all, transplants the μC/OS-Ⅱ operating system in theprocessor LM3S6911, designs drivers for each hardware module. System designs thespecialized dictionary font data structure, which makes it can achieve efficient retrievalfunction by using a simple two sub-queries algorithm. Dictionary front stored in the SD cardin the form of documents, therefore, the system also implements the related operations ofFAT16.