EGR 103/DAQ 2

This page contains pictures and graphs related to DAQ 2 for EGR 103. It has been updated for Fall 2015.

Notes

As before, if the system seems to not recognize Dev1, try Dev2 instead.

Pauses

There are pause commands in the code which will cause the program to...pause - specifically when the program first runs to check the lights. You will need to hit a key to un-pause the program. The way to see if the program is paused is to look at the bottom left corner of your MATLAB window - it will tell you if it is paused.

Graph Labels

For this particular assignment, you do not need axis labels. You need a title on each subplot, however.

Circuit for BasicAOutput

Circuit layout for BasicAOutput.

Circuit for BasicAIO

Circuit layout for BasicAIO (two measurements).

Graph from BasicAIO

Graph showing outputs when

Vout0 = 2.5+2.5*sin(2*pi*k/100);
Vout1 = 2.5+2.5*cos(2*pi*k/100);

That is,

\( \begin{align} V_{out,\,0}=2.5+2.5\sin\left(\frac{2\pi k}{100}\right)\\ V_{out,\,1}=2.5+2.5\cos\left(\frac{2\pi k}{100}\right) \end{align} \)

Circuit for AIO

Circuit layout for AIO (six measurements).

Graph from AIO

Graph showing outputs from six measurement channels.

Codes

Pasting codes from PDF files is...a bad idea. Here are the text versions of some of the codes in the assignment.

BasicAOutput.m

% Clear out workspace
clear

% Clear out DAQ objects
delete(daqfind)

% Create Analog Output Object
AO = analogoutput('nidaq', 'Dev1');

% Change sample rate
set(AO, 'SampleRate', 500);

% View Analog Output Object
AO

% Add channels to Analog Output Object
addchannel(AO, [0 1])







% Write values to output channels
putsample(AO, [5 5])
pause
putsample(AO, [0 0])

% Use loop to set several different voltages
for k=1:300
    % Calculate voltages for each channel
    Vout0 = 2.5+2.5*sin(2*pi*k/100);
    Vout1 = 2.5+2.5*cos(2*pi*k/100);
    % Put voltages to each output channel
    putsample(AO, [Vout0 Vout1])
    % leave line 31 blank for now
    % leave line 32 blank for now
    pause(0.02)
end








% Turn all outputs off
putsample(AO, [0 0])

BasicAIO.m

% Clear out workspace
clear

% Clear out DAQ objects
delete(daqfind)

% Create Analog Output Object
AO = analogoutput('nidaq', 'Dev1');

% Change sample rate
set(AO, 'SampleRate', 500);

% View Analog Output Object
AO

% Add channels to Analog Output Object
addchannel(AO, [0 1])

% Create Analog Input Object
AI = analoginput('nidaq', 'Dev1')

% Add channels to Analog Input Object
addchannel(AI, [0 4])

% Write values to output channels
putsample(AO, [5 5])
pause
putsample(AO, [0 0])

% Use loop to set several different voltages
for k=1:300
    % Calculate voltages for each channel
    Vout0 = 2.5+2.5*sin(2*pi*k/100);
    Vout1 = 2.5+2.5*cos(2*pi*k/100);
    % Put voltages to each output channel
    putsample(AO, [Vout0 Vout1])
    % Read voltages from all input channels
    Voltages(k,:) = getsample(AI);
    pause(0.02)
end

% Plot voltages versus index
n = 1:k;
Vleft  = Voltages(:,1);
Vright = Voltages(:,2);
plot(n, Vleft, 'g', n, Vright, 'r')
legend('Green LED', 'Red LED', 0)

% Turn all outputs off
putsample(AO, [0 0])

Function to Plot Curves

function CurvePlotter(Vin, MyAdjective)
subplot(1, 2, 1)
plot(Vin(:,1), Vin(:,1), 'k-',...
     Vin(:,1), Vin(:,2), 'b-',...
     Vin(:,1), Vin(:,3), 'g-') 
axis([-1 5 -1 5])
grid on
title(sprintf('%s Green', MyAdjective))
subplot(1, 2, 2)
plot(Vin(:,4), Vin(:,4), 'k-',...
     Vin(:,4), Vin(:,5), 'm-',...
     Vin(:,4), Vin(:,6), 'r-') 
axis([-1 5 -1 5])
grid on 
title(sprintf('%s Red', MyAdjective))

Script to Plot All Three Figures

% Small LEDs
load SmallData
figure(1); clf
CurvePlotter(Voltages, 'Small')

% Large LEDs
load LargeData
figure(2); clf
CurvePlotter(Voltages, 'Large')

% Rectangular LEDs
load RectData
figure(3); clf
CurvePlotter(Voltages, 'Rectangular')

Questions

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