[ Thanks to jcondon
for this link. ]
“This second of two articles details the nitty-gritty
expectations surrounding specialized hardware such as ports,
multimedia, filesystems, and bus support in the upcoming 2.4 Linux
kernel….“
“Compared to later editions of Linux 2.x, Linux 2.4 has very few
changes in serial ports. It is still possible to share IRQs. Some
special serial hardware devices, including multiport boards, are
better supported. That’s about it.”
“But the parallel port subsystem has undergone major changes.
2.4 features a generic parallel port driver for abstracted
communication with “unknown” types of parallel devices. Programs
can use this to do PNP polling. (A side effect of the parallel port
driver is that it allows the root console to be split out to a
parallel port.) It is possible to configure the parallel port
driver to cause console messages to be written out to a printer.
This is very useful for debugging when there is a problem copying
from the screen or using the printer as console on servers without
a CRT. Linux 2.4 supports writing to the parallel ports using DMA,
which speeds up access to printers.”
“Linux 2.2 had Infrared port support in special builds that is
now standard in 2.4.”