The first thing that I would suggest is to make sure you have the latest VISA driver. Make sure you get the full version.
http://digital.ni.com/softlib.nsf/websearch/8E7D54CA3A1FDECF86256E4D007ED2E0?opendocument&node=132070_US Then open up LabVIEW and run the Serial Communication.vi shipping example that can be found in the example finder. Connect pins 2 and 3 together on your serial port. Then run the example. You should be able to see the data being read back. If not, open the block diagram and set the handshaking so that it is set to none. Another good utility is portmon. You can use it and compare what windows is seeing across the serial port. It's very useful and it allows you to monitor the serial calls when hyper terminal or LabVIEW is running and then compare the differences. http://www.sysinternals.com/ntw2k/freeware/portmon.shtml If the program still doesn't work you might want to create a service request and call in. It's possible your serial port doesn't support the standard serial features that VISA tries to configure. For example if you serial port does not support handshaking and you try to set the handshaking to none it could cause problems, because the port will not understand the handshaking attribute or the setting of none. I hope this helps out. JoshuaP National Instruments
