#!/usr/bin/perl -w

use POSIX;

$fd = POSIX::open('/dev/ttyS1', O_RDWR | O_NOCTTY) or die "$! in open";
$termios = POSIX::Termios->new;
$termios->getattr($fd) or die "$! in getattr";
print $termios->getispeed, " ", $termios->getospeed, " ", POSIX::B9600, " ", POSIX::B38400, "\n";
$termios->setispeed(POSIX::B38400);
$termios->setospeed(POSIX::B38400);
$termios->setattr($fd,&POSIX::TCSANOW);

for (;;) {
    for ($i = 0; $i < 256; $i++) {
        $buff = chr($i);
        POSIX::write($fd, $buff, 1) or die "$! in write";
	select undef, undef, undef, 0.1;
    };
    for ($i = 255; $i >= 0; $i--) {
        $buff = chr($i);
        POSIX::write($fd, $buff, 1) or die "$! in write";
	select undef, undef, undef, 0.01
    };
};

POSIX::close($fd);