ai.llb ... where is it?

[jmb22]

Hi,

I have Labview 6.i under windows XP. I just purchased a PCI-6220 and want to read data from a couple of channels. I installed the software on the CD and also TDAQ741 downloaded form this web site. I want to write a vi with "AI Read One Scan.vi" but I cannot find the file in the NI folder. I also cannot find the ai.llb library.
Please, can you help and let me know what to do?

Thanks.

[xseadog]

Hi

I have Labview 8.2 so unable to really help, however

check out the following location : jump down into your NI software, labview folders :

\vi.lib\DAQ\1EASYIO.LLB\AI Sample Channel (scaled value).vi

hope that helps

[pincpanter]

Hi jmb22,
Below is an excerpt from the 7.4.1 DAQ Readme.htm.
You need either to use LV7.0 or later, either to download an older DAQ version.

NI Application Software Support

The following table lists the NI application software versions supported by NI-DAQmx and Traditional NI-DAQ (Legacy). If you are not using NI application software, refer to Microsoft Visual Studio Support.

NI Application Software	Versions Supported by NI-DAQmx	Versions Supported by Traditional NI-DAQ (Legacy)
LabVIEW	7.0 and later	7.0 and later
LabVIEW Real-Time Module	7.1 1 and later	7.0 and later
LabWindows/CVI	7.x and later	6.0—7.x
Measurement Studio	7.x and later	6.0—7.x2
1 To use LabVIEW Real-Time Module 7.1 with NI-DAQmx, you must use NI-DAQmx 7.2 or later.
2Traditional NI-DAQ (Legacy) does not include a Measurement Studio C++ or .NET interface.

[stilly32]

Hi,

Before you go off and download another driver, you should note that the 6220 only runs off of the DAQmx driver - the Traditional DAQ driver does not support this card. DAQmx is also not supported on LabVIEW versions 6.x and earlier - you need at least LabVIEW 7.0 or later to be able to use this card.

Hope this helps,

Andrew S

[jmb22]

Thanks for your help. Some progress here. I installed the trial version of LV 8.0. I got the vi working.
The purpose of the vi is to continuously read on two channels the voltage outputs by two independent equipment. The voltage ranges from 0 to +10 V. I used the DaqMax Assistant (powerful tool BTW...thanks for that).
I have a PCI-6220. The chosen channels are AI12 and AI9. In "DAQ Assistant Terminal configuration" I chose "RSE". I don't really know what this means so I'd really appreciate if someone could give more info on what those Config means.
For each equipment, the voltage measurements are done versus the ground. The computer and the 2 equipments are grounded.
The reading from the card is very noisy (~100mV noise on a ~8V signal). I checked that the noise does not come from the equipment that outputs the voltage by connecting it to a Keithley DC voltmeter (with Filter off).
Please, I would really appreciate to get some help here. The voltage reading must be accurate down to the mV (this should not be a massive job for this card !!!).     

[stilly32]

Hi,

RSE is short for Reference Single Ended - which probably means less to you than the letters. Here is a good link for the different grounding considerations. The first question I would ask is - where is your ground signal connected? For RSE, you'll want to go to AI GND. Also, when you say noisey do you mean there's an offset of 100 mV, or random noise of 100mV peak to peak centered around 8 V? Also, at what acquisition rate are you acquiring?

Let us know if grounding doesn't fix the issue.

Andrew S