Instrument I/O Assistant

Hello,
I have created a vi which uses the I/O assistant. I am having a problem in that when I create a runtime build from the vi which I have written (attached) I find that the data it extracts from the com port using I/O assistant is truncated. This only happens for the built vi. I install the built vi on a different computer but almost identical in setup.
The problem I have is that the data is truncated so it is not shown correctly. Ie 500E-3 will be read a 500. This seems to be a problem with long data about 7 or 8 characters long which is truncated incorrectly. It seems to be a problem with character count shown below. But I thought this command was not set and varies for each data point read not matter its length. It does say 'to end of data' so I must presume it reads to the end of the data. I nave tried Hyperterminal and it seems to acquire the full data point with E numbers so it seems to be a parsing problem. All I do after data acquisition is remove the first five characters leaving the reading. Any ideas.
Attachments:
BARA_FINAL.vi ‏429 KB

Put an indicator on the string wire that comes out of the I/O assistant. That will at least tell you whether you are getting all the data in your read.
Put an indicator ont he wire coming out of the string subset function to make sure you are getting the portion of the data you want.
Which I/O assistant are you working with? Are you sure you are using the one you think you are? It seems like overkill to have 3 of those in different cases. If you were using lower level VISA functions, you could put your serial write and read in the loop and just have the case structure select between different string constants to write. One problem with the I/O assistant is that it opens and closes the com port every time it is called. It is possible you are getting some amount of data in during the time the com port is actually closed.
The default data in your I/O assistant doesn't make sense. When I open up the 2nd one, it has .02e-3 in it which is a weird way to express a scientific notation number. But it still seems to go through the string to fractional number okay and show up as 2e-5. However in your message, you are talking about a 500e-3 number in your example.
Message Edited by Ravens Fan on 09-03-2009 12:13 PM

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Instrument I/O Assistant Help - Parsing Errors

Hello All -
I am having trouble working with a TSI DustTrak DRX - which does not have its own driver so I had to make one. At this point, all I want to do is send a command to the instrument and get an indicator to repeat what the output is. So far no luck.
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Thanks.

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Message Edited by Meghan R on 07-10-2007 02:26 PM

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feliciacpw92 wrote:
Hi,
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Hello!
I am currently trying to create an instrument driver for a Ballard "Nexa" fuel cell with the Instrument I/O Assistant.
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Click "Run this step" to read the data coming in from the serial port, but nothing happens until the the timeout set on the choose device tab has expired, then I get a timeout message (see attached picture).
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I a previous thread, I read that the Instrument I/O Assistant has a bug concerning the locale settings of windows:
http://exchange.ni.com/servlet/ProcessRequest?RHIVEID=101&RPAGEID=135&HOID=5065000000080000002DBF0000&UCATEGORY_0=_49_%24_6_&UCATEGORY_S=0&USEARCHCONTEXT_TIER_0=0&USEARCHCONTEXT_TIER_S=0&USEARCHCONTEXT_QUESTION_0=Instrument+I%2FO+Assistant+is+not+communicating&USEARCHCONTEXT_QUESTION_S=0
So I tried the same after switching my locale settings from german to english, but with no success, the I/O Assistant still seems to see not input.
Does somebody have another s
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Ingo.
Attachments:
errormsg.gif ‏5 KB

Hi TN,
As I just started using LabVIEW, developing an instrument driver seems like some pretty heavy stuff. For now, I´ve managed to have someone else write the communications backend, I´ll only do the data conversion and display. But I´ll for sure take a closer look at that communications VI so I ´ll get it done myself next time...
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Ingo.

Instrument I/O Assistant: Close I/O Instrument

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Instrument I/O assistant error msg "Unable to view proterties"

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Attach file description :
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Sorry, forget attach file!
Attachments:
Add_Remove_List.JPG ‏99 KB
Add_Remove_NI_List.JPG ‏132 KB
Instrument IO Assistant - Unableto view properties error.JPG ‏77 KB

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(I'm using Labview 7.1 on
Windows XP)
I have a problem communicating with a device over a serial port using my lab
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I have successfully communicated with the device on this computer using
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I am using the Instrument I/O assistant to get things up and running, this
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Luke_A_P

I have solved the problem!
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Luke
Luke_A_P

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