I am trying to open port COM1 at 115200 baud using the following code:
unless ($Port = new Win32::SerialPort($PortName)
    and $Port->baudrate($Baudrate)
    and $Port->parity('none')
    and $Port->databits(8)
    and $Port->stopbits(2)
    and $Port->handshake('rts')
    and $Port->buffers(4096,4096)
    and $Port->binary(1)
    and $Port->xon_limit(3000)
    and $Port->xoff_limit(300)
    and $Port->rts_active(1)
    and $Port->write_settings)
{
    $mw->messageBox(
        -message => "Can't open $PortName at $Baudrate baud.",
        -type => 'OK'
    );
    exit
}

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After first powering up my computer, it fails. Further investigation has shown that it's because COM1 doesn't, at this point, show 115200 baud as one of its capabilities (using WIN32API::CommPort's can_baud method). However, if I first open COM1 at 115200 baud using HyperTerminal, then close it, the above code will allow me to do so, too -- until rebooting. And, indeed, can_baud then lists 115200 as a capability for COM1. So what is HyperTerminal doing to force this capability that I can't also do in perl? Thank you!

In reply to Windows serial I/O by Anonymous Monk

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