Implementing a Windows virtual COM port via FTDI drivers in communication between a µFR reader and software can sometimes cause slow and unstable operation.
If you encounter this type of problem during the development of your project, you can avoid using FTDI D2XX drivers by communicating directly with the reader via the COM port.
For this you need to call the ReaderOpenEx function using the following parameters:

ReaderOpenEx (1, COMXX, 1, 0)

Replace “XX” with the actual COM port of your device.

Please find more details about the ReaderOpenEx function in theµFR Series APIdocument (pages 26-28).