FTDI drivers

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In case the usb port is not recognised by your machine, you might need to download the usb drivers at http://www.ftdichip.com/Drivers/VCP.htm

The procedure to manually add VCPs to a MAC is described here:

http://www.ftdichip.com/Support/Documents/TechnicalNotes/TN_105%20Adding%20Support%20for%20New%20FTDI%20Devices%20to%20Mac%20Driver.pdf