Adding serial and parallel ports

About parallel ports

By default, ISA parallel drivers are not configured into the kernel, so you must configure ISA parallel cards using the Hardware/Kernel Manager or mkdev parallel. ISA parallel ports configured in the system are assigned device nodes /dev/lp0, /dev/lp1, and /dev/lp2, respectively.

By default, the system is configured to support up to two PCI parallel ports. PCI parallel ports are detected at boot-time; the first port that is detected is assigned device node /dev/lp3, the second /dev/lp4, and so forth. (Note that ports beyond /dev/lp4 are ignored unless you run the Hardware/Kernel Manager or mkdev parallel to increase the number of allowed PCI parallel ports.

``Parallel port addresses and interrupts'' lists the addresses and interrupts associated with the different types of parallel ports:

Parallel port addresses and interrupts

Bus Physical Device IRQ Base I/O
type port name vector address
ISA LPT1 /dev/lp0 7 0x378
LPT2 /dev/lp1 5 0x3bc
EISA LPT1 /dev/lp0 7 0x378
LPT2 /dev/lp1 5 0x3bc
LPT3 /dev/lp2 5 0x278
MCA LPT1 /dev/lp0 7 0x378
LPT2 /dev/lp1 7 0x3bc
LPT3 /dev/lp2 7 0x278
PCI 1st port /dev/lp3 N/A N/A
2nd port /dev/lp4 N/A N/A

NOTE: Some EISA and MCA machines can assign any interrupt vector to the parallel ports. MCA machines and some others may swap the default addresses for LPT1 and LPT2.

See also:

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© 2003 Caldera International, Inc. All rights reserved.
SCO OpenServer Release 5.0.7 -- 11 February 2003