use strict;
require 5.003;
use Win32API::CommPort;
use Win32::SerialPort qw( :STAT 0.19);
use Win32;

my $quiet = 1; # Einschränkung bei Fehlermeldung
my $PortName = 'COM3';
my $configFile = 'ER400TRS.cfg';

my $PortObj = new Win32::SerialPort( $PortName, $quiet )
    or die "Can't open $PortName: $^E\n";

## initialize
$PortObj->user_msg( 'ON' );
$PortObj->baudrate( 19200 );
$PortObj->databits( 8 );
$PortObj->parity( "none" );
$PortObj->stopbits( 1 );

$PortObj->handshake( "none" );
my @ar=$PortObj->buffers( 128, 128 ); ## read buffer, write buffer

## write settings to com port
$PortObj->write_settings or undef $PortObj;
unless( $PortObj ){ print "can't change device control block: $^E\n"; }
## save settings in configuration file
$PortObj->save( $configFile ) or warn "can't save $configFile: $^E\n";

## close all stuff
$PortObj->close or die "failed to close";
undef $PortObj; ## frees memory back to perl

## open again with tie (needed for some functions)
$PortObj = tie( *COMFH, 'Win32::SerialPort', $configFile )
 or die "can't tie using $configFile: ^E\n";

### ready to communicate
##get current status

my $BlockingFlags;
my ( $InBytes, $OutBytes, $LatchErrorFlags );
( $BlockingFlags, $InBytes, $OutBytes, $LatchErrorFlags ) = $PortObj->status
        || warn "could not get port status\n";

if ( $BlockingFlags ) { warn "Port is blocked"; }
if ( $BlockingFlags & BM_fCtsHold ) { warn "Waiting for CTS (clear to send)"; }
if ( $LatchErrorFlags & CE_FRAME ) { warn "Framing Error"; }


#######write to serial port###################
my ( $count_out, $output_string );
$output_string = "Hallo ";

my $i = 10;
while( $i > 0 ) {
   $count_out = $PortObj->write( $output_string );
   warn "write failed\n"         unless ( $count_out );
   warn "write incomplete\n"     if ( $count_out != length( $output_string ) );
   $i--;
}

## close all stuff
$PortObj->close or die "failed to close";
undef $PortObj; ## frees memory back to perl