Example: capture analog streams with NationInstrument DAQ from MATLAB

capture.m

function [] = main()
close all;

% Make sure:
disp('Searching devices...');
devs=daq.getDevices();

if (length(devs.Vendor)~=1),
    error('Is the USB DAQ connected?');
end
dev=devs(1);
fprintf('Connected to: %s\n', dev.Description);

% Create session:
s = daq.createSession ('ni');

[ch1,idx1] = s.addAnalogInputChannel(dev.ID, 'ai1', 'Voltage');
[ch2,idx2] = s.addAnalogInputChannel(dev.ID, 'ai9', 'Voltage');

ch1.TerminalConfig='SingleEnded';
ch2.TerminalConfig='SingleEnded';

% Capture:
s.IsContinuous = true;
s.Rate = 1000;
s.prepare();

global GRAB;
GRAB=[];

disp('Push any KEY to START...');
pause;

%[data,timeStamps,triggerTime] = s.startForeground();
lh = s.addlistener('DataAvailable', @plotData); 

s.startBackground();

disp('Push any KEY to STOP...');
pause;

s.stop();
delete (lh);

FIL=sprintf('GRAB_%s.txt', datestr(now(),'yyyy_mm_dd_HH_MM_SS') ) ;
fprintf('Saving to: %s\n',FIL);
save(FIL,'GRAB', '-ascii');

end

function plotData(src,event)
    global GRAB;
    GRAB=[GRAB;event.TimeStamps event.Data];
    plot(GRAB(1:150:end,1),GRAB(1:150:end,2:end));
    title(sprintf('Valor: AL=%f F=%f',event.Data(end,1),event.Data(end,1)));
end