Hello, Am trying to use Win32::SerialPort on a portable strawberry perl implementation, version 5-32-1. (32 bit). Using it to try and set up a datalogger on a Win10 machine, for an instrument that reports through a RS232 output. Also have a general test bed which is two windows PCs connected by a serial cable, and one sending messages (from Powershell) to the other - which testing has shown acts in the same way as the end use. Have come across a variety of scripts online. For some reason though, I can't get any Perl script to output the RS232 input on its own. However, if I open and close the port in powershell, suddenly the exact same Perl script DOES work! The perl script continues to work as expected until the PC is rebooted. So I'm wondering if there's a key parameter needing to be set, which is sorted by Powershell but not by Perl? Couldn't see anything obvious in the SerialPort documentation. An example script that only works when powershell has "activated" the port is: 
use Win32::SerialPort;  # Use instead for Windows
my $port=Win32::SerialPort->new("COM1") || die "couldn't open COM1";
$port->baudrate(9600); # Configure this to match your device
$port->databits(8);
$port->parity("none");
$port->stopbits(1);
#$port->handshake("none");
$port->user_msg(ON);
print "Port COM1 successfully opened\n"; 
$count = 0;
my $chars=0;
my $buffer="";
print "1\n";
do {
       print "2\n";
       my ($count,$saw)=$port->read(255); # will read _up to_ 255 char
+s
       print "3\n";
       if ($count > 0) {
               $chars+=$count;
               $buffer.=$saw;
               print $saw;
       }
       print "4\n";
       $port->lookclear;
       print "5\n";
} while 1;
$port->close;

[download]
This code stops after printing "2" if I've not opened/closed the port in Powershell yet - it's the reading of RS232 input where the script seems to get blocked quite consistently across different scripts. Powershell code to open and close is: 
$port = new-Object System.IO.Ports.SerialPort COM1,9600,None,8,one
$port.open()
$port.close()

[download]
Powershell to send RS232 on test bed is: $port.WriteLine("test") Unfortunately access permissions do not let me run a powershell script, and I'd rather not have the end user have to manually type in powershell code each time the PC is turned on... Many thanks for any advice provided.

In reply to SerialPort issues under Windows 10 by clinicalAD

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