A portable computer system wherein the printer port can be used, at the user's option, not only for connection to a printer, but also for connection to an external floppy disk drive. If the BIOS determines that there is an external floppy drive attached, the BIOS disables the normal operation of the...http://www.google.de/patents/US5535371?utm_source=gb-gplus-sharePatent US5535371 - Portable computer with automatic adaption to different device types on a standard port
