The Design And Practice Of Bar Led-Screen Remote Control System

Compared with the traditional display equipments, the led-screen hasmany advantages, for example, the color is fresher and brighter, the informationcapacity is greater, the life span is longer,it runs on very little electricity, theweight is lighter, the stability is higher and operating, installing and maintenanceand so on are easier. So it plays an important role in the society. From on themarket demand, not only need a big scaled led-screen but also need install thesmall led-screens according to the different places. Among them, the bar characterdisplay screen is mainly used to announce some simple writing information, suchas bank, telecommunication office ,post , station, dock, and hospital etc..Though the application field of led-screen is more and more wide, but somenew problems are exposed in the application. Such as to update content mustemploy a computer, but the communications between a computer and a led-screenare limited in the certain distance, which is difficult to come a remotecommunication true ; Sometimes one computer can only real-timely control a ledscreen.So the single body invest of the system is greater, the expense ofmaintenance and administrative is also higher, which restricts application of theled-screen. If we can throw a calculator away or several display screenscommunally use one computer, which can effectively reduce the devotion andwidely expand the applying scope of the led-screen.Domestic and international LED manufacturers have also studied on theremote control, and put forward some projects, but all have some restriction in theactual movement, for example, if the some manufacturers leads the Internettechnique into a remote communication, that is, each led-screen is still adopted anoriginal computer system, making computer and Internet connect with each other,carrying on data exchanges with computers through Internet. This kind of methodcan work from the principle, but still have a very big problem in using practically.Because the customer's each led-screen is requested to connect with Internet, which currently can only come true in local region with the Internet. From onmanagement, this kind long range control way can't solve the need of no computerequipments on the spot; the administrative expense everyday is still higher thanoriginal. So this kind of method actually uses a little.To solve the two problems of refreshing data using PC and remotecommunication, the thesis brought forward new control technique with MCU,which took designing the control system of"electron doorplate"for instance. Wemainly described in the thesis the designing process with MCU for core, replacingthe control system of 485 interface technology with pc machine coming true along range control. This design can lower the usage cost of whole manifestationsystem, more conveniently take and operate more flexible, can carry out the spotcontrol, can even adapt the need of common customer, have better marketforeground.This thesis studied the control method of bar led-screen, as follows:The first, elaborated a led-screen of development and foreground, the keyanalyzed work principle of led-screen and the structure and related parameters andconcrete caring out process, which concretely include the choice and control ofMCU and affiliated chips, the basic component of hardware electric circuit andsoftware describe of the workflow. In the form manifestation system design, inconsideration of the speed of disposing information, adopted a double MCU ofSTC12C5410AD in the system. The main MCU is responsible for carrying oncorrespondence with exterior long range controller and refreshing contents ofdisplay screen, and can also directly carry on initializing to the clock chip ofDS1302 and the SHT sensor of the humidity degree. The subsidiary MCU canthen independently carry on refreshing the current time and the data of thehumidity degree and display the data in corresponding number tubes. Because ofthe system needing very big of work electric current, so chose to use the function better switch power to supply the whole system.The second mainly solves the design method of MCU control system.Include the realization of hardware electric circuit, the choice of the MCU modeland the input method, the type matrix pick-up technique, and studiedcommunication problem. The working process of the control system as follows:the customer inputs The information into long range controller, and then thecontroller converts the information into corresponding frame data, was deliveredby 485 total lines to the terminal display(extension), to come true remotecommunication. After each display terminal correspondence interface receives astring data, the information is stored into buffer section and according to thecontrol information delivers the manifestation data to the unit of the latticedisplay screen, completing the whole process. For improving the reliability of thesystem, adopts the MCU of STC12C5410AD, this series MCU has single clock/ aperiod(1 T) of machine is compatible with 8051 MCU kernel, have highspeed/less power, all new flowing water line/simplify instruction gather structure,internal integration MAX810 resetting electric circuit, having functions, such aselectric voltage monitor and watchdog etc., applying this model number of MCUcan raise a system processing speed and can prevent from system because ofpower supply interference and other interferences the device appears power off.This control system still provided with OCM4X8C 12864 liquid crystal displays,exteriors saving machine and matrix type keyboard, can convenient customerrenewal the screen contents and complete a related constitution.The third, the price of the remote control system using MCU lowersobviously, but MCU remote controller remains not agile compared with the PCmachine software control in Chinese characters record, can't change the fontfreely, so this thesis still mainly aimed at the usage need of customer who alreadyhas PC, resolved to use PC as long range controller problem, and described indetail concrete the process. We used Microsoft Visual Basic 6.0 soft to edit textinformation and withdraw and deliver word pattern information, set the show effect and preview characters and communication etc. Among them, the key pointdiscussed the advantages and disadvantages of picking-up character models withisn inquire method and image element method, and carry on introduction to theMSComm components which can carry out serial communication.In this thesis through the research of above contents, it discussed a workprinciple of the bar lattice display screen, design method and the systemcommunication and so on, carrying out a design of the related hardware electriccircuit and software, the physically applied effect is better.