基于FPA的门禁系统设计.doc

摘 要 门禁系统是集计算机技术、电子技术、数字密码技术为一体的机电一体化高科技产品，具有安全性高，使用方便等优点。本论文从门禁系统系统整体功能，硬件电路设计、软件设计等方面阐述密码门禁系统设计过程。 密码门禁系统系统包括电子锁，电子钥匙，用户卡及用户卡生成器四部分。电子锁里保存着当前开门密码，以及用户第一次使用用户卡时的用户卡号和加密位。用户凭用户卡在门上随时更改开门密码，更新或配制钥匙里的开门密码。 本系统考虑到门禁系统成本及体积因素，在设计门禁系统部分时，以FPGA 为核心；由多个数码管，按键和发光二极管组成外围电路。 本文采用VHDL语言使用自顶而下的方法对系统进行了描述。采用FPGA开发设计，所有算法完全由硬件电路来实现，使得系统的工作可靠性大为提高，同时由于FPGA具有在系统可编程功能，当设计需要更改对，只需更改FPGA中的控制和接口电路，利用EDA工具将更新后的设计下载到FPGA中即可，无需更改外部电路的设计，大大提高了设计的效率。因此，采用FPGA开发的数字系统，不仅具有很高的工作可靠性，其升级与改进也极其方便。 关键：FPGA VHDL Abstract The technology of access control system combines computer, electronics and digital coding technology together, and seems to be a high-tech electromechanical integration product, can be used safely and easily. This paper discussed the whole system architecture of the access control system; hardware design and software design were presented separately. The whole password access control system consists of four parts: electronic lock, electronic key, user card and user card generator. The electronic lock is used to preserve the current unlock password, the user card numbers and encrypted spaces. Users can use the card to unlock the lock, update or preparation the unlock password at any time. The cost and size are put most emphasis in the design of access control system. Design based on FPGA is presented. The system then is designed and verified through some external circuit components, such as keyboard and LEDs. The paper is described with VHDL using the top-down approach.FPGA-based development and design which is achieved all entirely by the hardware circuit algorithm，makes the system work much more reliability，as well as because FPGA in the system can be made available for the in-system programmable function，when the design needs to be changed，the control and the interface circuit can be restructured in the FPGA conveniently，using EDA tools，to download the updated design to the FPGA without changing the external circuit design．So the efficiency of the design Can be proved．T