#! C:\perl\bin\perl.exe

use strict;
use warnings;

use Win32::SerialPort;

my $port_name = 'COM5';
my $config_file = 'setup.cfg';

my $port = new Win32::SerialPort($port_name, $config_file) || die "Unable to open: $^E\n";

# my $status = pack('HHHHHH', 'ca', '00', '01', '00', '00', 'fe');

$port->write("ati"."\n");
sleep 0;

my $debug = 1;

while(1) {
    my $line = $port->lookfor();
    if( $line ) {
        {
            local $/ = "\r";
            chomp $line;
        }
        if ($debug)   {  print "[$line]" ;}
        # Some data processing takes place
    } else {
        sleep(1);     # Allocate time for other processes to run
        print ".";
    }
}

======================= Response ==================
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