Dear Monks!

I am desparately trying to connect to a serial port. However whatever I do, it simply walks through my <FH> or $PortObj->input statements. Currently I am testing between 2 PCs using perl on one end, Teraterm on the other

Just for completeness: This is perl 5, version 16, subversion 1 (v5.16.1) built for MSWin32-x64-multi-thread (strawberry perl) OS is WinXP 32bit SP3

This is my script:

use Win32::SerialPort qw( :STAT 0.19 );
use Convert::ASCIInames;
use String::HexConvert ':all';
#use strict;

$PortName = "COM1";
$Configuration_File_Name = "Serial_Settings.cfg";

$PortObj = new Win32::SerialPort ($PortName, $quiet)
       || die "Can't open $PortName: $^E\n";    # $quiet is optional

#$PortObj->user_msg(1);
$PortObj->databits(8);
$PortObj->baudrate(115200);
$PortObj->parity("none");
$PortObj->stopbits(1);
$PortObj->handshake("none");
$PortObj->buffers(4096, 4096);

$PortObj->are_match("\n");    # possible end strings

$PortObj->read_interval(100);    # max time between read char (millise
+conds)
$PortObj->read_char_time(5);     # avg time between read char
$PortObj->read_const_time(100);  # total = (avg * bytes) + const
$PortObj->write_char_time(5);
$PortObj->write_const_time(100);

$PortObj->write_settings || undef $PortObj;
$PortObj->save($Configuration_File_Name);

$PortObj->close || die "close failed";
undef $PortObj;
#---------------------------------------------------------

$PortObj = tie (*FH, 'Win32::SerialPort', $Configuration_File_Name)
       || die "Can't tie: $^E\n";
       
$PortObj->are_match("\n","\r");    # possible end strings
$PortObj->write_settings || undef $PortObj;
$PortObj->lookclear;                  # empty buffers

sleep 5;
print FH "Enter string:\n"; # works well
my $out = <FH>;    # shouldn't this be blocking?
print "$out\n";

print FH "Enter another string:\n"; # works well
my $out = <FH>;    # shouldn't this be blocking?
print "$out\n";


close FH || warn "close failed";           ## CLOSE     ##
undef $PortObj;
untie *FH;                                 ## DESTROY   ##
[download]

Whats the problem? I sometimes receive the right chars from serial port, but seldom all. The expected behavior is that the script waits at <FH> for an input with enter. Instead it just goes through. If I put the <FH> ito a loop then I can randomly catch my input.

I am using the native RS232, but I saw similar behavior with Win7 and USB a serial adapter. Any hints? Please save my strong believe into Perl :-)

Cheers and thanks, Archie