How fast is a parallel port?

[Paul de Bra]

In article <1991Feb25.220636.23155 at cbnewsh.att.com> wcs at cbnewsh.att.com (Bill Stewart 908-949-0705 erebus.att.com!wcs) writes:
>I'm trying to find out how to connect big laser printers (50-100ppm)
>to normal computers, in particular to 386/486 boxes running UNIX.
>For a variety of ugly reasons, I don't want to use Ethernet -
>I'd really like to use a parallel port.  But nobody I've talked to
>knows how fast a parallel port can go on a typical machine, and
>nobody's tried it at speeds over about 10ppm.
>
>50-100 ppm is 1-2 pages/second, or typically 40-80 kilobits/second;
>not much faster than a 38.4 kbps RS-232 port.

Using the non-interrupt parallel driver (pp) which is public domain
one can drive the parallel port as fast as it can go.
The maximum speed depends largely on the combination of printer and
interface. (there is a big difference between interface boards)

I tried several interfaces on my Everex Step 386/25 and a Nec P5 printer,
and at 360dpi the best I got was about 3 seconds per 'line', which
means about 4kbyte per second. This most certainly will not be enough
to keep a fast printer busy, especially not when you are printing bitmaps.

Paul.
(debra at win.tue.nl, debra at research.att.com)