Unable to Communicate over Serial Protocol using USB to Serial Converter in Phar Lap

Updated Feb 26, 2019

Reported In


  • USB-485
  • USB-232


  • NI-Serial

Issue Details

I am using an instrument or sensor which has a serial port. I connected the instrument to a PharLap Real-Time (RT) PXI controller using a third party USB to Serial Adapter. Why am I not able to communicate with the instrument?


Drivers of Serial to USB converters from vendors other than NI, might not be supported by LabVIEW and LabVIEW RT hence you might not be able to communicate over this device. NI recommends customers to use the NI USB-232 or NI USB-485 USB to Serial Converters for Windows Targets as both converters are fully supported by NI-Serial for Windows Targets.

Please note that both converters are not fully supported as serial interfaces for Real-Time Operating Systems, such as Phar Lap, and will be identified as a USB RAW device.
For a full list of supported serial interfaces under Phar Lap Targets please check the according NI-Serial for LabVIEW Real-Time Readme file .


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