| With the development of the information technology, there is a growing tendency for the application of hand-input products. Now hand-input products represented to the tablet are used to the handwriting recognition, and high-density and high-quality real-time writing could not come true. The interactive electronic white board could record the handwriting in real time and display on the computer, and replace of the mouse action, it has a wide foreground of application. But the bulk of the interactive electronic white board is big, and needs to be used with computer, so it not convenience to used. Based on the researches carried on the above two technologies and the blackboard DM4600.Lab of Signal Processing of Jilin University independently designed and invented the U-disk-notebook based on ultrasonic infrared allocation technology.In the process of a system design, we can have a complete record of the real-time written content using the ultrasonic infrared allocation technology to confirm the location of the signal pen on the board. And we can save the written content in a U-disk by USB technology. The entire system is compatible with the file formats of the Windows operating system, thereby, it gets rid of the depending on the computer when carrying on a U-disk saving. At the same time, it can also connect with the computer directly through the USB port, makes the written content show up on the computer screen meanwhile.U-disk-notebook is cabinet, light enough, and easy to carry, it could be widely used in all kinds of teaching and office affairs. At the same time, it reserves the traditional habit of people writing to record on a sheet of paper. It is also easy to operate, and there is no need for the users to master the computer technology, it has a more widely applicable crowd.This paper is mainly based on the realization of the basic function of the U-disk-Notebook and the improvement of the overall hardware and system software optimization are completed. Its main tasks are the design and implementation of low-power system and power supply. The design of a complete signal capture procedures is also included using new signal pen instead of the old signal one, which achieves a more stable writing result. At the same time based on the existing system, we further improve the system software, and perfect the system function. In addition, considered the needs of product of the system, the design of the structure and implementation of the U-Disk- Notebook are also processed.This paper reads as follows.Chapter 1 briefly expatiates on the modern office and teaching development trend. The advantages and social values of the U-disk-notebook are discussed. The status of the research is introduced and the overall structure of the full text is outlined at the same time.Chapter 2 introduces the overall U-disk-notebook design idea. And we expound the theory of method from the aspects of the principle of the position, the signal optimization as well as the USB Communication theory.Chapter 3 mainly introduces the data structure and management methods of the U-Disk file system. We also determine the U-disk-notebook in the host mode data storage method through experimental data analysis.Chapter 4 expounds low power design of the U-disk-notebook. The design is mainly from the aspects of designing a processor, USB communication circuit, dynamic power management and power supply circuit.Chapter 5 completes the optimization of the system software, including the design of the signal receiver capture process and the host system optimization procedures.Chapter 6 expounds PCB system design and the analysis of system testing results.Chapter 7 is the conclusion of the full paper and research projects in the outlook.The main work and contributions of this article are as follows.1. In this article, the hardware circle and software are progressed based both on the searching on the low power cost of the system and the need to take the equipment more conveniently.a) The system uses two power supplying modes. The U-disk uses the 5V power and both the receiving circuit and USB communication circuits use the 3.3 V power. According to the needs of the product, we choose the low voltage power supply pattern and paste the piece type seal the monolithic integrated circuit to take the CPU of the system, and made improvements to the correlation electric circuit in order to adapt the low voltage power supply design.b) Optimizing the logical design in the procedure, taking full use of the electricity falling pattern of CPU and the USB connection chip, the supersonic signal processing electric circuit uses the timesharing/district power supply technology. When there is no written movement, the system will be cut over to low power loss pattern by a timer time way automatically; If there is one , the system will be awaken and the signal automatically cut over to the active status by the infrared signal's achievement.2. This article selects the rising voltage chip MAX1676 to design the power feeding circuit and the power source to transforming chip TPS76033 to realize 5V and the 3.3V regulated supply outputs according to the need of the system. In order to suppress EMI(Electromagnetic Interference), we uses the damping technology in the circuit design and the LC filter circuit to reduce the ripple, so we get to the point that the regulated voltage output has been realized which the system needed.3. This paper tests and researches on problem of the "near poor writing results", suggests programmes of the use of new signal pen, analysis through comparison of the two types of T characteristics of the signal output, completes the delay of the design process of extraction and designs based on the agreement of USB1.1 data transfer procedures and improves the effectiveness of the near writing.4. This paper studies the applications of USB communication protocol in the basic norms of embedded system and FAT16 file system in the U-disk format in document .Introduces the new function on how to check the remaining space of U-disk, creates functions on documents and directories, completes the function on design and implementation procedures.5. This paper PCB suggest a reasonable shielding technology in design system and optimize the layout alignment, thereby reduces external noise, electromagnetic interference and electrostatic interference, and improves the noise performance of U-disk-notebook, improves composite indicator of the positioning accuracy, real-time, the edge and the effect of the writing of U-disk-notebook, joins products of hardware and software to get debugging prototype.The research of this paper is part of the project of The Ministry of Science and Technology Innovation fund of Miniature and Medium-sized Enterprise called U-Disk-Notebook Based on Wireless allocation technology(No.D5c26212200372), which is already achieved State invention patents (No.200510016846.5) and State utility model patents (No.200520028732.8). The performance of the manufacture is already passed appraisal of the Jilin Province Electronic & Information Products Superintending & Inspecting & Research Institute(No.W07177). |
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