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From: DPM on 30 May 2007 07:39
I'm trying to use a call to:

l = ComDBGetCurrentPortUsage( HComDB,
bufBits,
256,
CDB_REPORT_BITS,
pMaxPortsReported );

to determine if a USB serial port device is plugged in. Before plugging in
the device, the device manager reports that I have 2 COM ports and 2 printer
ports. After plugging in the device it reports 3 COM ports and 2 printer
ports. However, before plugging in the device, a call to
ComDBGetCurrentPortUsage fills in the bit array with 05 00 00... and after
the call it still returns 05 00 00... (for COM 1 and COM 3) How can I
determine if the USB COM device has been plugged in and if it has, what
number has been assigned to it?

It returns these values even if I powered up with the device unplugged.

The call to ComDBGetCurrentPortUsage is in a dll written in 'C++'. The call
to the dll is from a routine written in Visual Basic.

Thanks for your help
--
Regards,
Dean


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