... 2nd Edition June 2001 . ... I/O Ports and I/O Memory . ... Although playing with scull and similar toys is a good introduction to the software interface of a Linux device driver, implementing a real device requires hardware. ... Up to now, we have examined the internals of software concepts; this chapter completes the picture by showing you how a driver can access I/O ports and I/O memory while being portable across Linux platforms. ... Back to: Linux Device Drivers, 2nd Edition . ...