Computer device manager to identify the COM1, COM300, COM301 three port equipment,
But the Java software, the use of RXTXcomm. Jar,
Through the Enumeration portEnum=CommPortIdentifier. GetPortIdentifiers ();
Can only access to the COM1,

But the manual COM300 COM301 into less than under COM256, Java software can identify that
COM256 is manually choose port can choose the maximum value, who knows the reason for this problem?
Why more than COM256 port, Java software through RXTXcomm package can't identify?

Note: I can identify to port, so should not RXTX DLL didn't put the cause of the position,