sampling increase buffer size

[Fibo]

hello, I'm trying to sample my scxi module (SCXI-1100 32Ch analog input module) at 10Hz... so I'm taking my samples in a timed while loop... I was wondering if I had this wired correctly... I'm sampling 16 inputs of the scxi-1100... inside my timed while loop I have set up "NChan 1Samp"..... I keep getting the increase buffer size error.... but I'm only taking 1 sample.... I'm not sure where I've gone wrong... I'm including a picture.... much thanks.

[10Degree]

I am not 100% sure without mucking around with this myself, but it looks like you are using the create channel vi twice when you set up the analog input.  I don't think the first is necessary (AI Voltage).  Try whacking this one and just configuring the thermocouple channel only.

-cb

[Hillman]

Hi Fibo,

Thanks for the post!

If you require to do continous aquisation you need to read Nsamples.. i.e. to pull all the samples collected out of the buffer when you loop re-iterates.

I would recommend looking in the example finder (Help>>Find Examples...Hardware Input/Output>>DAQmx>>Analog..

Im pretty sure this would explain the buffer zier error.

** Its fine to have two create channels, if you want to change the settings relating to each channel. You just cant have mutiple Analog Tasks.

Let me know what you think,

Kind Regards, 

Message Edited by Hillman on 10-15-2008 09:14 PM

[Monse]

Thanks for the suggestions.... I create two channels because I'm taking samples from two different modules... should I do all of this in one create channel vi?

I will check out that example now, thanks for the tip

[Hillman]

Hi Monse,

Let me know how you get on.

So for one device, you can only have 1 AI task, because you'll only have 1 Analog Sample Clock.

If you have two devices, then you'll have two samples clock and hence you can have two analog tasks (i.e. two create channel vi's).

Kind Regards,