介紹一種基于單片機控制的數控直流電流源。系統以AT89S52單片機為控制核心，由V/I轉換電路、DA轉換、AD轉換等模塊組成。通過按鍵設定電流值，并在LCD上同步顯示預設值，利用模擬閉環控制原理實現V/I轉換功能，采樣電阻兩端的電壓值送給A/D轉換電路，經單片機換算成實際輸出電流值，并利用LCD顯示，供用戶參考。經測試，本系統穩定性好、精度較高、操作簡單、人機界面友好。在科學研究和設備生產中，能夠廣泛應用到這種可靠性高、操作簡單的數控電流源，不僅能夠提高設備的性能，同時能夠縮短研發周期，本系統具有較高的實用性。
上傳時間： 2013-11-06
上傳用戶：csgcd001
針對船舶對中小型信息監控終端的需求，提出了一種基于AVR單片機的設計方案。以AVR單片機為核心，采用LCD控制器RA8835實現對液晶顯示模塊的控制，通過軟硬件的緊密配合，實現信息圖文并茂的實時顯示，以及液晶對比度的調節。試驗結果表明，該終端在高溫高濕、低溫高濕等惡劣環境條件下，顯示清晰、工作穩定。
上傳時間： 2013-11-16
上傳用戶：農藥鋒6
為降低汽車倒車時的碰撞事故，提出了一種基于單片機的超聲波測距倒車雷達的設計方案。該設計根據超聲波測距原理，采用AT89S52單片機為控制核心，設計了超聲波測距倒車雷達，并對測量距離誤差進行了分析。測量距離為0.1～5.0 m，其精度經過校正后可達1 cm。該設計結構簡單、工作可靠，有良好的測量精度和靈敏度。
上傳時間： 2013-11-10
上傳用戶：songkun
介紹了一種基于單片機的區域交通信號控制系統設計方案，闡述了系統的工作原理及各主要模塊的軟硬件實現方法。系統能夠根據車流量信號動態地改變交通信號燈各狀態配時，并通過無線通信技術，有效地解決了特定區域內各路口信號機之間數據的傳輸，實現了區域交通信號的智能控制。該系統抗干擾能力強，可靠性高，使用非常方便。
上傳時間： 2013-10-21
上傳用戶：kinochen
一、 main.c(35): warning: #128-D: loop is not reachable from preceding code 原因，前面有一個while(1){ …….} 二、 main.c(54): warning: #1-D: last Line of file ends without a newLine 少了一個回車在}之后
上傳時間： 2014-12-26
上傳用戶：sjb555
為解決當前計算機串行通訊接口只有USB，難以滿足舊型號設備或某些單片機要求RS232通訊的問題，設計出兩款RS232/USB電路。采用CH341A與MAX223集成電路芯片構建標準9線RS232/USB通用接口轉換器，無需編程。采用CH341A與PIC16F877A構建單片機與計算機之間的USB通訊電路，軟件遵循RS232通訊協議，硬件進行電平轉換。實際使用表明，這兩款產品與計算機端Windows 操作系統下的串口應用程序完全兼容，且通訊過程中無握手失敗現象。 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.
上傳時間： 2013-11-03
上傳用戶：siying
提出一種基于凌陽單片機的步進電機加減速的控制方法。采用凌陽科技推出的16位結構工控單片機SPMC75F2413A為控制器，由Allegro公司生產的兩相步進電機專用驅動器件SLA7042M構成步進電機的驅動電路，在傳統的3段直線加減速控制算法基礎上增加至7段S形曲線加減速過程，控制步進電機的啟動和停止。實驗結果表明，該控制方法克服了直線加減速中不連續、易造成系統沖擊的問題，整個系統實現柔性控制，電機啟動、停止連續性能提高30%。 Abstract: The method of controlled stepping motor is referred based on SPMC75F2413A MCU， which adopts the 16 knots SPMC75F2413A MCU as the controller. The special-purpose actuation chip SLA7042M of two stepping motor produced by Allegro Corporation constituted to actuation electric circuit. The purpose of increasing to seven section of S shape curve based on the traditional three sections of straight Line is to control the start and stop process of stepping motor. The experimental results show that the control method solves easy to pull-out and overshot problems. The overall system realizes flexible control， and the performance of motor start or stop continuity is increased 30%
上傳時間： 2013-12-08
上傳用戶：jiangfire
單片機作為一種微型計算機，其內部具有一定的存儲單元（8031除外），但由于其內部存儲單元及端口有限，很多情況下難以滿足實際需求。為此介紹一種新的擴展方法，將數據線與地址線合并使用，通過軟件控制的方法實現數據線與地址線功能的分時轉換，數據線不僅用于傳送數據信號，還可作為地址線、控制線，用于傳送地址信號和控制信號，從而實現單片機與存儲器件的有效連接。以單片機片外256KB數據存儲空間的擴展為例，通過該擴展方法，僅用10個I/O端口便可實現，與傳統的擴展方法相比，可節約8個I/O端口。 Abstract: As a micro-computer,the SCM internal memory has a certain units(except8031),but because of its internal storage units and the ports are limited,in many cases it can not meet the actual demand.So we introduced a new extension method,the data Line and address Lines combined through software-controlled approach to realize the time-conversion functions of data Lines and address Lines,so the data Lines not only transmited data signals,but also served as address Lines and control Lines to transmit address signals and control signals,in order to achieve an effective connection of microcontroller and memory chips.Take microcontroller chip with256KB of data storage space expansion as example,through this extension method,with only10I/O ports it was achieved,compared with the traditional extension methods,this method saves8I/O ports.
上傳時間： 2014-12-26
上傳用戶：adada
詳細介紹工控軟件組態王與單片機多機串口通訊的設計原理。分析組態王提供的直接與單片機串口通信方法的優點，給出系統基于RS-485總線傳輸的接口電路原理圖。根據組態王提供的通訊協議和單片機多機串口通訊的原理，給出程序設計流程與思路。 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.
上傳時間： 2013-12-19
上傳用戶：tecman
Mega16是一款采用先進RISC精簡指令，內置A/D的8位單片機，可支持低電壓聯機 Flash和EEPROM 寫入功能；同時還支持 Basic和C 等高級語言編程。用它設計電子時鐘不僅成本低，硬件簡單，而且很容易實現系統移植。介紹了如何利用AVR系列單片機Mega16及1602字符液晶來設計電子時鐘的方法，同時給出了相應的電路原理及部分語言程序。 Abstract: ?Mega16 is a high-performance, low power consumption, the use of advanced RISC concise instructions, built-in A/D 8-bit microcontrollers, the on-Line support for low-voltage Flash, EEPROM write function. Except Mega16 also support the Basic, C, and other high-level language programming.The electronic clock which is deisgned by Mega16 is not only low-cost, simple hardware, but easy to achieve system migration.The design method of electrioic clock based on the AVR Mega16 and character LCD1602 is introduced in this paper,and the corresponding circuit electrionic and some language program are given.
上傳時間： 2014-12-27
上傳用戶：zl5712176
