The parallel device provides a hardware-independent interface to the
Amiga's Centronics-compatible parallel port. The primary use of the Amiga
parallel port is for output to printers, but with its extensions for
bi-directional I/O, it can also be used for communication with digitizers
and high-speed links with other computers.  The parallel device is based
on the conventions of Exec device I/O, with extensions for parameter
setting and control.

 parallel device commands and functions 
 device interface 
 ending a read or write with termination characters 
 setting parallel parameters 
 querying the parallel device 
 additional information on the parallel device