error in parsing data from instrument i/o assistant

[James Liou]

I have used a GPIB card to talk with a HP53131 Counter. I tested the command in the Instrument IO Assistant, the data it reads back is good and never show a problem. But when I link output to text pallet or a chart, the data is wrong. I should get 5e6, it gives me 5e66. I can fix this by put a division in to data pipe-line. But the labview program has other errors too. for about 10-15% of the probability, Instrument IO Assistant outputs very high or low numbers like 55e66, or 0. Also fairly high interuption due to "GPIB scaning errors" (no less than 5% probability). Does anybody know such bugs from Instrument IO Assistant?

I used the same hardware and HP provided software in Excell. It can contiue take data for 1 wee
k and does not break. No error readings.

Thanks in advance
Regards
James

[TommyTestBoy]

James - what does the response you are parsing look like? I know of one bug that exists in the Assistant that this could be; if you show me a sample response I can let you know if this is a known issue or a new one.

[James Liou]

Tommy,

In the parsing window, I see the right number. But when it sends it out to other VIs, the number is wrong. I tested the assistant many times, I did not catch the error I saw outside. The VIs I used to check the Asistant are:chart, array (saved to file) and text box. All show the same wrong number if one does.

Attached is the VI I used to test and some saved data after divided by 1e60

[TommyTestBoy]

James, this is a very interesting problem. I am trying to get my hands on an HP 53131 or something similar to see if I can reproduce what you are seeing. One option you can try is to right click on the Instrument I/O Assistant block and select "Open Front Panel". This will convert the Express VI to a SubVI, meaning you cannot pull up the Instrument I/O Assistant again from that block, but then you can see the LV code and maybe you can tell where the error is occurring in the generated LabVIEW code. I will continue to try to reproduce the problem from my end. Thanks for your feedback and help!

-Tommy

[Zaw]

Hello

I am using LabView 7.1 to control the Agilent 33250A. I also have that error what jame had got. I try to read back the value from the device and it sometime show wrong value and sometime it's correct. Maybe it's the same bug as what james have. Can you kindly tell me how do i solve this problem. Thanks

Thanks & Regards,

Zaw

[Dennis_Knutson]

Why are you using the instrument assistant instead of the driver? You have both an IVI and native LabVIEW driver available. Why don't you try one of these?

p.s. this is another thread you hijacked.