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Has anyone run into problems using FTDI direct driver functions while using VISA to write/read  to a VCP in same VI?  When I use the direct diver alone in a labview VI I see FT_STATUS = FT_OK from the point of opening the device to reads, writes and closing.  I have a board with a micro and FT232RL for the USB and a RS-232 connection on a separate buffered port on the micro.  I am trying to put together a VI to echo messages into USB and out RS-232 and vise-versa.  I can get this to work using a VI (FTDI example LabVIEW_String_7.0 with while loop added) with direct driver functions and another serial Port terminal which is written in C#.  I think there is an issue using the direct driver so I have been trying to get a VCP to work for the USB connection to the FTDI converter - but no luck so far.

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Hi TTL4,


Which FTDI direct driver are you utilizing in LabVIEW?  How are you making the calls to this driver?



Daniel Dorroh
National Instruments
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Are you trying to make one direct call and one VCP call to the same FTDI chip? The 232HL creates two VCP (COMn and COMn+1). Device Info List says there are two devices. I can't throw a loopback on, right now, but I can open COMn with VISA and Device Index 1 (but not 0) with the driver - no errors.

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