LPT(4)

NAME
lpt - Parallel port driver

SYNOPSIS
For interrupt-driven ports:
device lpt0 at isa? port "IO_LPT1" tty irq 7 vector lptintr
device lpt1 at isa? port "IO_LPT2" tty irq 7 vector lptintr
device lpt2 at isa? port "IO_LPT3" tty irq 7 vector lptintr

For BIOS-probed ports:
device lpt0 at isa? port? tty irq 7 vector lptintr

For polled ports:
device lpt0 at isa? port? tty
device lpt1 at isa? port "IO_LPT2" tty

DESCRIPTION
This driver provides access to parallel ports.

The driver can be configured either to be either interrupt-driven, or to poll the printer. Ports that are configured to be interrupt-driven can be switched to polled mode by using the lptcontrol(8) command.

This driver replaces the functionality of the lpa(4) driver, which is now defunct.

FILES
/dev/lpt0
    first parallel port driver

SEE ALSO
lptcontrol(8)

BUGS
There are lots of them, especially in cheap parallel port implementations.

It is only possible to open a lpt port when a printer is connected and on-line, making it impossible to run lptcontrol(8) when there is no printer connected.

This driver could still stand a rewrite.