The platform consists of a dc motor , a decelerating mechanism , a driving unit , an i / o circuit of interface , several kinds of sensors and a pc with control software . the communication between the software and the hardware can be implemented on the basis of pc parallel port . this platform uses computer control technology to realize its functions , but for users it can achieve analogue and digital control 平台由直流电机、机械减速装置、驱动模块、 i o接口电路、各种传感器件和安装了控制软件的个人计算机组成，软硬件通过计算机并行口进行通讯，其内核采用计算机控制技术，对用户来说既可以作为模拟控制器，也可以实现数字控制器。
Abstract : a kind of microcomputer control system for teaching is presented . this system is composed of 89c51 microcomputer and its periphery circuit . many kinds of experiments of software and hardware can be done by this system , and the students can be trained in both programming and operational ability 文摘:介绍了一种用于单片机实验的多功能教学控制系统.该控制系统以89c51单片机为核心，进行了串、并行口的扩展和外围电路的设计，可进行单片机教学的多种软、硬件实验，这样既可以锻炼学生的编程能力，又有助于提高学生的操作能力
The relevant program of both the dongle and the computer have also been developmented . a parallel port and a serial port are provided for the pcb . there is a program ( in vhdl , vhsic hardware description language ) carrying out in the pld which implementi ng the parallel protocol . an encrpt arithmetic is designed and embeded in pld . to providing a interface for the user , a dll ( dynamic link library ) is developmented in c + + builder 所设计的电路板上可以选择连接串行口或者并行口，在pld内用vhdl ( vhsichardwaredescriptionlanguage ，硬件描述语言)实现了并口的通信协议和一个自行研制的密码算法，并在c + + builder环境下开发了配套的上位机软件，主要是提供了dll (动态链接库)和一些函数用于pc机和加密锁之间进行通信。
Based on analyzing the development and tendency of interface technique , the generalized interface is presented in this paper , which is following the design principles - high speed , convenience , high reliability , cheapness . this interface makes the switching input / output and analogue input / output to use the same enhanced parallel port by using the in - system programmable logic device - isp1032e 本文在分析接口技术的发展历史及发展趋势的基础上，本着顺应接口发展趋势以及高速、便用、可靠、经济等设计原则，设计开发了基于计算机并行口epp工作模式及在系统可编程逻辑器件isp1032e的开入、开出、模入、模出四路复用计算机并行口的通用接口。
The function of the software use pc - computer to dispose the output signal which is produced by the device as following steps : ( 1 ) to input data by parallel interface ( 2 ) to record and form a file ( 3 ) to demonstrate results step by step ( 4 ) the results could be compiled ( 5 ) it can synthesis in the permitted error scope , substituted original dot for line or arc , finally we could get a graph that is described by some simply curve . ( 6 ) to convert these graph into a program , which used in the cutting process of numerical control . ( 7 ) the software also includes some protective methods 而系统处理软件的作用是：利用pc兼容机，将上述装置的输出信号( 1 )通过并行口输入( 2 )记录成文件( 3 )逐点显示出来( 4 )可人工进行化简，编辑(删、改点)等( 5 )可在给定误差范围内进行人工拟合，用直线和圆弧取代原来的点，得到一个与原图形的误差在规定范围内，又消除跟踪过程中因受到各种干扰而造成的缺陷，由尽可能少而简捷的数学曲线描述的图形( 6 )把这些图形转化成用于编制数控线切割加工程序及autocad能够识别的文件(主要指dxf格式) ( 7 )该软件还有一定的加密措施。
The paper lays a strong emphasis on discussing the realization of the autocontrol of raster scanning of the scanner in x - y dimension , the " tapping " of the cantilever of the tappingmode afm by a direct digital synthesizer . then a method of parallel communication between dsp and pc in epp mode is given . finally , the author discussed the digital pid closed loop control of the scanner in z - direction , the automatic approaching of the tip using step - motor , and also some electro - magnetic interferences 论文首先简单介绍了扫描探针显微镜的发展、分类、工作原理及应用；接着对ti公司的tms320vc5402dsp的特点及外围扩展作了简单介绍；然后分章节重点讲述了利用vc5402dsp实现扫描探针显微镜的核心部件? ?压电陶瓷管的x向和y向的光栅扫描控制；借助直接数字集成器( dds )实现轻敲式原子力显微镜的微悬臂的“轻敲” ； vc5402dsp的主机接口( hpi )与pc机在增强并行口( epp )模式下的通信；论文最后还介绍了扫描管z向的数字pid闭环控制，步进电机的自动进针，并对实际出现的一些电磁干扰问题作了讨论。
