% MATLAB supports M-Series, E-Series, and USB hardware from
% National Instruments with the Data Acquisition Toolbox.  This basic code
% example shows you how to use MATLAB to sample from two analog input
% channels and put the data out on two analog output channels

% Use this command to determine Board IDs in system, if needed
%hw = daqhwinfo('nidaq')
%hw.InstalledBoardIds
%hw.BoardNames

% Create an analog input object using Board ID "Dev1".
ai = analoginput('nidaq','Dev1');
% Create an analog output object using Board ID "Dev1".
ao = analogoutput('nidaq','Dev1');

% Data will be acquired from hardware AD channels 0 and 1
addchannel(ai,[0 1]);
% Data will be sent to hardware DA channels 0 and 1
addchannel(ao,[0 1]);

% Review the basic configuration of the acquisition by typing
% the name of the variable.
% ai

% Use this command to see properties that can be configured
% set(ai)

% Use this comment to get a listing of all object properties and
% their current settings
% get(ai)

% Configure the analog input for single-ended or differential mode
set(ai,'InputType','SingleEnded');
%set(ao,'InputType','Differential');

numsamps = 500;  % take 500 samples
% allocate a data array to save data from AD channel 0
alldata = zeros(numsamps,1);  

tic;  % start the timer so we can calculate sampling rate when finished
% acquire the samples
for i = 1:numsamps
    % get data from the analog input channels
    data = getsample(ai);  
    
    % --------
    % you would put your control law here
    % --------
    
    % put data on the analog output channels
    putsample(ao,data);
    
    % save AI channel 0 into a data array 
    alldata(i) = data(1);
end
% put zero volts on the AO channels when you are finished
putsample(ao,[0 0]);
% calculate your average sampling rate
samprate = numsamps/toc

% Graphically plot the results
clf;
plot(alldata,'.');
shg;

% Clean up
delete(ai);
delete(ao);