Still to do in the implementation:

- Only build Python support based on a configure check

- Only build xmlto documentation based on a configure check

- Find a (portable if possible) way to accurately sleep with ms accuracy
  (scheduling can cause problems here)

- F1284_EXCL for iopl() and /dev/port (use /dev/lp0).  This needs
  configuration file support.

- Default implementations of the block transfer functions, in terms of
  the pins.

- Bounded ECP mode.

- Notice/handle USB printers, at least for device IDs.

--
Tim Waugh <tim@cyberelk.net>