ICP DAS USA PDS-700 Series, Руководство пользователя

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PDS Series User Manual ( V1.4, Oct. 2009) ----- 182
2.
How to open a virtual COM port that larger than "COM 9" by calling
CreateFile() Win32 API?
If you want to open "COM 10", the correct way to call the CreateFile() is as follows:
CreateFile(
"\\\\. \\COM10", // address of name of the communications device
fdwAccess, // access (read-write) mode
0, // share mode
NULL, // address of security descriptor
OPEN_EXISTING, // how to create
0,
// file attributes
NULL // handle of file with attributes to copy
);
NOTES:
1. This syntax also works for ports COM 1 through COM 9. See more... MS Q115831 .
2. Maximum COM port number for VxComm Driver is COM 256.
3. Valid COM port number for MSCOMM.OCX is between 1 to 16. Please refer to
MSComm.CommPort .
4. The "\\.\" prefix must be add to the COM port name (device name) when it is larger
than "COM 9". But please note that the "\" character is a special escape symbol in
C\C++ language, thus you have to use "\\\\.\\" prefix in C\C++ language.