But looking at the Win32::SerialPort docs, that doesn't look like it's the problem. W32::SP seems to expect to find the port in the registry.

I don't have a serial port on this box here, but do a quick search under \\HKEY_LOCAL_MACHINE\HARDWARE for COM1, and see if COM6 is defined there. (I hope that's where com ports would be...)

It's possible your other applications are finding it via "well known" IRQ/IO settings, and not via the registry.

If it's not in your registry, how to add it will depend on your version of Windows, unfortunately. Look for "Ports" in the Control Panel, if you're lucky.
--
Mike

In the registry is:
\Device\Serial0 ... COM1
\Device\Serial1 ... COM2
\Device\vspciser0 ... COM4
\Device\vspciser1 ... COM5
Winachsf0 ... COM3

The setup runs fine on COM1 and COM2, and when on COM4 or COM5 the script returns no errors when opening the port but still never "sees" any data on the port. If I shutdown the script and launch the win32 app it reads the waiting data.

-Nitrox

Hmmm... Did you try referring to it with the "vspciser0" name? There's an example in the perldocs that shows that usage.

That's just a wild guess, though. :(
--
Mike

-Nitrox

Here's a snippet of my test stub:

my $ob = Win32::SerialPort->new("COM5") || die("Couldn't open COM5");
$ob->baudrate(19200);
$ob->parity("none");
$ob->databits(8);
$ob->stopbits(1);
$ob->handshake("none");
$ob->write_settings || die("Couldn't write serial port settings");
[download]

-Nitrox