Abstract: An intelligent card reader is provided to replace existing magnetic stripe readers, bar code readers, and Wiegand effect readers without the need for expensive retrofitting of existing computer systems which are coupled to the existing readers. The intelligent card reader can replace the aforementioned readers and yet remain compatible with their existing interfaces by emulating a magnetic card reader, a Wiegand effect reader, or a bar code reader. Moreover, the card reader can accept smart cards having different functions and/or software interfacing techniques, thus allowing different types of smart cards can be used in the same reader. A reprogramming feature allows the unit to be easily reprogrammed to support new features and smart card types without rewiring or removing the unit.