Švieslentės valdiklio tyrimas

Abstract

Baigiamojo magistro darbo tiriamasis objektas viešojo transporto informacinė sistema, naudojama Vilniaus miesto autobusuose. Tyrimo tikslas – išanalizuoti tris dažniausiai naudojamas informacines sistemas bei ištirti jose naudojamus duomenų perdavimo protokolus. Uždaviniai – išsiaiškinti duomenų perdavimo protokolų struktūrą ir sukurti valdiklį, gebantį valdyti švieslentes, naudojamas visose trijose informacinėse sistemose.

Research subject of the master thesis is scoreboard controller. Objective of the study - investigate different electromechanical flip-dot information display systems used in Vilnius public buses. Tasks - analyze and fully decode data protocols used by different vendors to control flip-dot displays and develop universal controller capable of controlling all of different kinds of flip-dot information signs. In the literary analysis part three main flip-dot information display systems used in Vilnius public buses are described. Articles with descriptions of different electromechanical display systems components have been given. In theoretical part widely used parallel and serial data transmission buses are described. A detailed list of hardware and software tools, which could be used for analysis of unknown data transmission protocols, is provided. In research part data protocols used by three different vendors to control flip-dot displays was fully decoded. A comparison of different data transfer protocol structures was provided. A unique controller capable of controlling all of different kinds of flip-dot displays was designed: functional and principle electrical diagrams of the controller, algorithm and microcontroller control program were engineered. Principle of operation of the electromechanical flip-dot display was investigated. Various electric current oscillograms ware obtained and explained. The influence to amplitude of electromagnetic coil current made by “sluggish” or damaged flip-dot segments was determinate. In the generalization part conclusions and recommendations are given.