Control PCI-6115 by matlab

[jfcc]

HI,
I try  to use matlab 2007a to control my PCI-6115. There are a strange problem, I can acquire correct data(a DC 5V voltage) when I use LabView but when I use matlab there is always strange noise which is close to zero. How could I make this daq card work normally? thx

[rpurser]

Hi,

Can you tell us more about how you have the card configured (single ended, differential, input range, AC/DC coupling?)  Are you using NIDAQmx or Traditional NI-DAQ?  Can you post some MATLAB code?

-Rob

[jfcc]

HI,
I give a 5V DC input and a 1.5V form a battery and use the MATLAB example code form here.

ai = analoginput('nidaq','Dev1');
addchannel(ai, 0);
ai.SampleRate = 10000;
ai.SamplesPerTrigger = 10000;
start(ai);
wait(ai,2);
data = getdata(ai);
plot(data);
stop(ai);
delete(ai);

[rpurser]

By default, I believe we will automatically choose ac coupling for this device.  You may want the Coupling property on your channel to be set to DC, if you're using a battery.

-Rob