🚀 go-pugleaf

Hello  Giuliano,

Let me explain:

I installed a bluetooth dongle and became 9 serial blue tooth ports, some 
are only for reading, others just for writing.
I'm not quite sure how everyhing works, the menuitmes are in Chinese and 
that's a little diificult for me.

But in contrast with a 'normal'  usb to serial plug, those ports dont's 
disappear after the dongle is unplugged
They are visible in the hardware-view and in the windows register.

So the software thinks the ports are present, tries to open them and maybe 
that's the reason it takes such a long time.

But even if the dongle is plugged in it takes some time to detect which 
ports are in use.

In fact I'm using then API232 functions like sio_open, but the results are 
the same.

Regards,

Anton






"Giuliano" <nonfracassatelepalline@non_fracassate_le_pall.ine> schreef in 
bericht news:vegkp3hhb89k52eol1c49492gc46k3iedv@4ax.com...
> Il Fri, 25 Jan 2008 14:26:01 +0100, "Anton" <acvoosten@zeelandnet.nl> ha 
> scritto:
>
> [snip]
>>With a few of those existing virtual ports which are not really active, it
>>takes more then 10 seconds to open them and that's just the thing I want 
>>to
>>avoid.
>>Maybe there's a timeout you can set or something else?
> [snip]
>
> Hi Anton
>
>    ten seconds? Uhm... I never seen a such behaviour when opening a com 
> port.
> For example, AFAIK, if the USB of a virtual COM port is unplugged, the 
> port simply
> disappears. However, I use the following code to detect if a comport 
> exists and if it's
> available. The fn returns true if the com exists and set the 2nd parameter 
> to true
> if it's busy.
>
> bool IsComPortAvailable( int PortNumber, bool& InUse )
> {
>    AnsiString const ComName = AnsiString( "\\\\.\\COM" ) + PortNumber;
>
>    HANDLE const hComm =
>        CreateFile(
>            ComName.c_str(),
>            GENERIC_READ | GENERIC_WRITE,
>            0,
>            0,
>            OPEN_EXISTING,
>            0,
>            0
>        );
>
>    if ( hComm == INVALID_HANDLE_VALUE ) {
>        DWORD const dwError = GetLastError();
>        if ( dwError == 5 )  // Port exists, but cannot be opened
>            InUse = true;
>        else if ( dwError == 2 )  // Port does not exist
>            return false;
>    }
>    else {
>        CloseHandle( hComm );
>        InUse = false;
>    }
>
>    return true;
> }
>
> Regards
>
> Giuliano
>