LPT(3) LPT(3)
NAME
lpt - parallel port interface
SYNOPSIS
bind -a #L[123] /dev
/dev/lpt[123]data
/dev/lpt[123]dlr
/dev/lpt[123]pcr
/dev/lpt[123]psr
DESCRIPTION
The lpt driver provides an interface to the parallel inter-
face normally used for printers. The specifiers 1, 2, and 3
correspond to the parallel interfaces at PC ports 0x378,
0x3bc, and 0x278 respectively.
Lpt?data is write only. Writing to it sends data to the
interface. This file is sufficient for communicating with
most printers.
Lpt?dlr, lpt?pcr, and lpt?psr are used for fine control of
the parallel port. Reading or writing these files corre-
sponds to reading and writing the data latch register,
printer control register, and printer status register.
These are used by programs to drive special devices. The
data is written as a hexadecimal (leading 0x), octal (lead-
ing 0) or decimal number. Reads return a hexadecimal number
representing the value of the register.
SOURCE
/os/*/devlpt.c
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