为解决当前计算机串行通讯接口只有USB，难以满足旧型号设备或某些单片机要求RS232通讯的问题，设计出两款RS232/USB电路。采用CH341A与MAX223集成电路芯片构建标准9线RS232/USB通用接口转换器，无需编程。采用CH341A与PIC16F877A构建单片机与计算机之间的USB通讯电路，软件遵循RS232通讯协议，硬件进行电平转换。实际使用表明，这两款产品与计算机端Windows 操作系统下的串口应用程序完全兼容，且通讯过程中无握手失败现象。 Abstract: To solve the problem that current computer serial communication only with USB interface can not satisfy with the old type equipments or MCU to communicate with RS232， two kinds of RS232/USB circuit were designed.CH341A and MAX223 integrated circuit chips were used to create a standard 9-line RS232/USB universal interface convertor without programme. CH341A and PIC16F877A chips were adopted to build the USB communication circuit between computers and MCU. The software follows RS232 communication protocol， and the hardware converts electrical levels. Actual practices indicate that the two manufactures are compatible with serial application program of Windows operation system completely，and get avoid of handshake lost.
上传时间： 2013-11-03
上传用户：siying
单片机通讯电路的抗干扰设计
上传时间： 2013-12-20
上传用户：jing911003
详细介绍工控软件组态王与单片机多机串口通讯的设计原理。分析组态王提供的直接与单片机串口通信方法的优点，给出系统基于RS-485总线传输的接口电路原理图。根据组态王提供的通讯协议和单片机多机串口通讯的原理，给出程序设计流程与思路。 Abstract: In this paper，the design principle of communication between multi-SCM and KingView by serial ports is described in detail.We analysis the advantage of method supplied by KingView,by which KingView can communicate with serial ports of SCM directly，and provide the system’s interface circuit based on the RS-485transmission line.We provide flow diagram of programming and thinking on the basis of communication protocol supplied by KingView and principle of communication among multi-SCM through serial ports.
上传时间： 2013-12-19
上传用户：tecman
介绍一种基于CAN总线的牵引变电站自动化系统通讯规约的设计，CAN通讯规约采用标准帧，报文采用主动发送和发送查询两种处理形式。该设计在城市轻轨与地铁牵引变电站中的应用表明：可实现间隔层和通讯处理层的数据快速、可靠的交换，提高牵引变电站的安全性和稳定性 。 Abstract: This paper firstly presents a kind of design dealing with communicational protocol to the traction substation automation system based on CAN bus,and then comes up with the ideas that all frames of CAN communicational protocol should adopt the standard frame,and that messages be processed by two ways:sending initiatively and sending quiries.Subway and light rail application shows that the use of the CAN bus is possible to exchange data quickly and reliably between the layers of the middle and the communicational processing,hence to improve the safety and stability of traction substations.
上传时间： 2013-11-07
上传用户：bs2005
基于幅移键控技术ASK（Amplitude-Shift Keying），以C8051F340单片机作为监测终端控制器，C8051F330D单片机作为探测节点控制器，采用半双工的通信方式，通过监控终端和探测节点的无线收发电路，实现数据的双向无线传输。收发电路采用直径为0.8 mm的漆包线自行绕制成圆形空心线圈天线，天线直径为（3.4±0.3）cm。试验表明，探测节点与监测终端的通信距离为24 cm，通过桥接方式，节点收发功率为102 mW时，节点间的通信距离可达20 cm。与传统无线收发模块相比，该无线收发电路在受体积、功耗、成本限制的场合有广阔的应用前景。 Abstract: Based on ASK technology and with the C8051F340 and C8051F330D MCU as the controller， using half-duplex communication mode， this paper achieves bi-directional data transfer. Transceiver circuit constituted by enameled wire which diameter is 0.8mm and wound into a diameter （3.4±0.3） cm circular hollow coil antenna. Tests show that the communication distance between detection and monitoring of the terminal is 24cm，the distance is up to 20cm between two nodes when using the manner of bridging and the node transceiver power is 102mW. Compared with the conventional wireless transceiver modules， the circuit has wide application prospect in small size， low cost and low power consumption and other characteristics.
上传时间： 2013-10-19
上传用户：xz85592677
串口与单片机通讯问题
上传时间： 2013-11-12
上传用户：wbwyl
摘要：介绍用MCS-51系列单片机控制手机收发短信息的原理、硬件电路、PDU数据格式和符合GSM07.05协议要求的短信息发送/接收程序，同时给出了一个应用实例。关键词：单片机子 短信息 PDU GSM 接口
上传时间： 2013-11-19
上传用户：lingfei
将AVR上的队列串口驱动程序修改后，运行在STM32开发板，采用中断方式接收和中断发送，并加入了缓冲收发队列操作。由于该驱动是用来操作西门子的TC35或MC55等通信模块，所以加入了“等待串口接收完成”函数，该函数需要一个10ms的定时进行计数累加。
上传时间： 2013-11-11
上传用户：kaixinxin196
介绍了一种基于单片机和GSM模块的短消息收发系统设计。该系统通过串12'通信实现单片机与GSM模块间数据传送。同时完成了基于Visual Basic语言的PC机上位机程序开发工作，实现在PC上位机环境中对短消息进行编写，读取、发送、删除等多种功能。该系统具有成本低，功耗小，使用方便等优点，拥有良好的使用价值和工程指导意叉。
上传时间： 2013-11-08
上传用户：fghygef
本文介绍RS一485电气特性和简单的结构方式。以及采用RS485自定义实现 串行通信协议，并介绍单片机RS一485多机通讯的方法和技巧。
上传时间： 2013-10-15
上传用户：我们的船长
