How to use Extech Instruments model 407123 with Labview 7.1

Question

I am pretty new to Labview.  With the help of this forum I was able to configure my DAQpad 6020E with my Labview 7.1.
Now I am looking at using an Extech Instruments Hot Wire Thermo-Anemometer (407123) in my experiment and running it through Labview.  Based on my research, I was led to believe that I should use the Instrument Assistant I/O and NI-Visa, but I am having a lot of difficulties.  First off, the Thermo-anemometer is wired for RS232 and I have it connected to an RS232 to USB converter, which is then plugged into my computer.  I have the driver for the converter.  When I plug the thermo-anemometer into my computer, MAX reads it as a serial port and it is listed as COM3.  MAX claims that the device is working properly.  However, when I run Labview's Instrument Assistant I/O, and tell it to read data I get a bff0015 error and it says that the device timed out.  I have tried changing the time and I still get the same error.  I am assuming this means that Labview and my device are not communicating.
I have seen some mention of instrumentation drivers, but I haven't been able to find any for my particular device.  I am assuming that is the root of my problem, and that if I had an instrument driver to run my device in Labview that it would work properly.  So here are my questions.
1)  What do I need to take data from a third party thermo-anemometer in Labview?
2)  Am I correct in thinking I need some sort of instrument driver?  And if so, where could I find one (I have already searched for one and did not find it)?
3)  Is it possible and practical to take data through Labview from a DAQpad and a third party instrument at the same time?
4)  Are there any guides or tutorials I could use that may show me how to accomplish what I'm trying to do?
Thanks.
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Answer 1

I've been trying numerous things to get this to work, and I've had little luck in getting exactly what I want.  I have been able to get data from some example VI's designed for serial read, and I was able to tweak them some, but this data seems to be only able to be saved to a .txt file.  I want the data from my anemometer to be read along with the time it was read and stored in a spreadsheet.
Instrument I/O Assistant appears to have exactly what I need to do this, but I can't get it to work.  I keep getting the bff0015 error, which is that the device timed out before the operation completed.  I don't understand why it is doing this, or how to stop it, because I am able to get data from the device otherwise.  In fact, following these steps I can see the exact data I want:
1.  Open Instrument I/O Assistant
2.  On "Select Instrument" I select the correct port and then click "properties"
3.  At the top corner of the window I click "Open VISA Session"
4.  Once there, I go to the "Basic I/O" tab.  Within that tab I click the "Read" tab.
Please see attached screenshots if you want to see what I'm talking about below.
At this point I can read the data from my device.  The default count value is 1024 bits.  If I click "execute" the device is read and I can read the data in the textbox that says "buffer."  However, my device only makes one 16-bit reading every 1.6 seconds, so I have to let the device sit for some time before it can fill the buffer up with 1024 bits.  If I don't, the reading takes place, I can see all of my data in the buffer, but the "Return Count" value on the screen is something significantly less than the "Count" value.  This makes sense because the buffer did not have time to fill.  Needless to say, the "Return Value" says "bff0015" which means it would return the time-out error.
If I wait for the full time for the buffer to fill, OR if I change the "count" value to something significantly lower, say... 32 bits, the buffer "fills" much faster, the "return count" count is correct, and the "return value" reads "3FFF0006" which I assume is a standard code meaning everything went correctly.  I also notice that if I wait long enough, the buffer will continue to fill, and I can click "Execute" many times rapidly and get readings instantly.  I can tell that the program is just reading data stored in the buffer when it doesn't take a second to perform the reading, and if I continue to click "Execute" rapidly, I will eventually expend the data stored in the buffer and I will start to see the "fresh" readings again.
So here is my question.  How do I lower the expected "count" value in the actual "Instrument I/O Assistant"?  I can do it in the "Open VISA session" under properties, but the only thing I can change in the Instrument I/O Assistant is the timeout value, but even when I set the value to 5 minutes, I still get the time out error.  What else can I do?
Attachments:
Instrument IO view select.pdf ‏119 KB
Instrument IO view read.pdf ‏125 KB