【正文】
bottle neck in serial munication. This paper introduced a simple and convenient method to design a USB apparatus, that is to say, to realize an intact USB apparatus with a minimum system of singlechip puter that made of 51 singlechip puter and USB interface, the circuit greatly improves munication rate. In this system, I adopted 51 onechip puters AT89S52 as its controller, the chip PDIUSBD12 of PHILIPS Company as its electric interface. The onechip puter as the next machine, exchanges the data with the PC, through the USB bus and USB electric interface chip, and it realizes the logic function of USB apparatus. It can exchange data with PC, and realize its expanding function, through connecting with PC.Key words: singlechip puter system;interface technolo