#!/usr/bin/perl

use strict;
use warnings;

my $port = "/dev/ttyUSB0";

open (SERIALPORT, "+<", "$port") or die "can't open $port. ";
print SERIALPORT chr(254);
print SERIALPORT chr(27);
my $result = getc(SERIALPORT);
print ord($result) . "\n";

close (SERIALPORT);

##</code><code>##

#!/usr/bin/perl

use strict;
use warnings;

my $port = "/dev/ttyUSB0";

open (SERIALPORT, "+<", "$port") or die "can't open $port. ";
select(SERIALPORT), $| = 1;
print SERIALPORT chr(254);
print SERIALPORT chr(27);
my $result = getc(SERIALPORT);
print ord($result) . "\n";

close (SERIALPORT);

##</code><code>##

#!/usr/bin/perl

use strict;
use warnings;
use Device::SerialPort;

my $ob = Device::SerialPort->new("/dev/ttyUSB0") || die "Can't open port: $!";
$ob->baudrate(115200) || die "failed setting baudrate";
$ob->parity("none") || die "failed setting parity";
$ob->databits(8) || die "failed setting databits";
$ob->handshake("none") || die "failed setting handshake";
$ob->stopbits(1) || die "failed setting stopbits";
$ob->write_settings || die "failed writing settings";

my $cmd1 = chr(254);
my $cmd2 = chr(27);
$ob->write($cmd1);
$ob->write($cmd2);

open(LOG, ">>", "test2.txt") || die "can't open log file: $!";

open(DEV, "<", "/dev/ttyUSB0") || die "can't open prt: $_";

select(LOG), $| = 1;

while($_ = <DEV>) {
 print LOG $_;
}

undef $ob;

##</code><code>##

#!/usr/bin/perl -w

use strict;
use warnings;
use Device::SerialPort;

my $port = Device::SerialPort->new("/dev/ttyUSB0");
$port->databits(8);
$port->baudrate(115200);
$port->parity("none");
$port->stopbits(1);
$port->handshake("on");
$port->write_settings;

$port->write(chr(254));
$port->write(chr(27));

my $char = $port->lookfor();
if ($char) {
 print "$char";
}