Design of ID card reader based on USB interface

In this paper,the design of USB interface ID card reader based on SN8P2201 and EM4095 is presented.Combing the features of microcomputer and Manchester code,the design uses the means of counting carrier between the falling edge intervals in Manchester to decodes.It improves the decoding speed and accuracy.USB simulates output of the keyboard without PC software.The distance between the card reader and card reaches five centimeters.This design is especially suitable for internet management and attendance machine and so on,and the design has operational stability and broad application prospects.