609 KB27 KB198520252001Ratej, BorisSvečko, Rajkoštevilka:3letnik:31str. 185-190ISSN:0352-9045COBISSID:6757142URN:URN:NBN:SI:doc-QZX6KY2OslStrokovno društvo za mikroelektroniko, elektronske sestavne dele in materialeInformacije MIDEMidentifikacija osebmikrokrmilnikinadzorovanjepristopsistemiMikrokrmilniški sistem brezkontaktne identifikacije in nadzora pristopa| Microcontroller contactless identification system and access control|The basic operations in the access control systems are identifications. They are divided according to identifying instruments on the PIN code, magnet storage media, fingerprint, voice, etc. and by procedures themselves divided into the contact and contactless ones /2/. Since the contactless memory medium has many advantages /5/, the contactless identification system LEGIN /8/ is used in the access control system which is described in this paper. This device is a Radio-Frequency Identification (RFID) system that is composed of three components - an interrogator (reader), a passive tag, and a host computer. The tag is composed of an antenna coil and a silicon chip that includes basic modulation circuitry and non-volatile memory. The tag is energized by a time-varying electromagnetic radio frequency (RF) wave (carriersignal) that is transmitted by the reader. A passive RFID tags use the backcatter modulation to send data back to the reader. By repeatedly shunting the tag coil through a transistor, the tag can cause slight fluctuations in the reader's RF carrier amplitude. This amplitude modulation loading of the reader's transmitted field provides a communication path back to the reader. In order to read multiple tags simultaneously, the tag and reader must be designed to detect the condition that more than one tag is active. A number of different methods are in use for preventing collisionsV članku opisujemo mikrokrmilniški sistem identifikacije oseb zaradi pristopa v prostore z uporabo brezkontaktnih identifikacijskih medijev. Sistem identifikacije in nadzora sestavljajo nadzorni računalnik, vmesnik med RS232 in CAN vodilom, CAN vodilo in mikrokrmilniški vmesniki, ki upravljajo čitalnike brezkontaktnih identifikacijskih medijev, krmilijo električne ključavnice, tipkovnice, LCD prikazovalnike ter druge svetlobne in zvočne naprave. Poleg identifikacije nudi opisani sistem tudi beleženja delovnega časa in popoln nadzor nad pristopi v posamezne prostore. Omogoča zajemanje podatkov o času prihoda-odhoda, pregled nad pretokom ljudi med prostori in nadzorovan pristop v vsak prostor, ki je vključen v sistem. Vsi dogodki se zapisujejo v podatkovno bazo na nadzornem računalniku, kjer so mogoče različne statistične analize o zasedenosti prostorov, izkoriščenosti opreme, prisotnosti uslužbencev itdTEXTznanstveno časopisjejournalsSlovenian National E-content AggregatorNational and University Library of SloveniaStrokovno društvo za mikroelektroniko, elektronske sestavne dele in materiale