NAME

Sys::PortIO - perform direct port I/O from Perl

SYNOPSIS

use Sys::PortIO;

port_open($portnum);
write_byte($portnum, $value);
$value = read_byte($portnum);
port_close($portnum);

DESCRIPTION

This module provides a Perl interface to the low-level port I/O operations provided by Linux, FreeBSD, or OpenBSD. Among other things, this is useful for writing Perl scripts that interface with parallel, serial, or joystick ports.

BUGS

On some systems (for example, Linux), doing a port read or write on an unopened port will cause a segmentation fault.

TODO

Support optional range argument to port_open().

Set $! on errors, instead of dying (sometimes with a segfault).

Alternately, automatically open ports as needed.

SEE ALSO

Linux I/O port mini-HOWTO: http://www.faqs.org/docs/Linux-mini/IO-Port-Programming.html

On Linux or other glibc systems, see ioperm(2), inb(2), and outb(2). FreeBSD uses /dev/io for port access. On OpenBSD and NetBSD, see i386_iopl(2) and sysarch(2).

AUTHOR

Andrew Ho, <andrew@zeuscat.com>

COPYRIGHT AND LICENSE

Copyright (C) 2005 by Andrew Ho.

This library is free software; you can redistribute it and/or modify it under the same terms as Perl itself, either Perl version 5.6.0 or, at your option, any later version of Perl 5 you may have available.