Acquiring and Generating Data at the Same Time with Digilent Analog Discovery
This example shows you how to synchronously generate and acquire voltage data at a rate of 300 kHz.
Discovery Digilent Device
Discover Digilent devices connected to your system using daqlist
daqlist("digilent")
ans = 1×4 table DeviceID Description Model DeviceInfo ________ _____________________________________________ ____________________ _______________________ "AD1" "Digilent Inc. Analog Discovery 2 Kit Rev. C" "Analog Discovery 2" [1×1 daq.di.DeviceInfo]
Create a DataAcquisition for a Digilent Device
Discover Digilent devices connected to your system using daqlist
dq = daq("digilent")
dq = DataAcquisition using Digilent Inc. hardware: Running: 0 Rate: 10000 NumScansAvailable: 0 NumScansAcquired: 0 NumScansQueued: 0 NumScansOutputByHardware: 0 RateLimit: [] Show channels Show properties and methods
Add an Analog Output Channel
Add an analog output channel using the listed Digilent device with ID AD1
, channel ID 1
, and measurement type Voltage
.
addoutput(dq, "AD1", "1", "Voltage"); addoutput(dq, "AD1", "2", "Voltage"); ch_out = dq.Channels(1:2); ch_out(1).Name = "AD1_1_out"; ch_out(2).Name = "AD1_2_out"
ch_out = Index Type Device Channel Measurement Type Range Name _____ ____ ______ _______ _____________________ ____________________ ___________ 1 "ao" "AD1" "1" "Voltage (SingleEnd)" "-5.0 to +5.0 Volts" "AD1_1_out" 2 "ao" "AD1" "2" "Voltage (SingleEnd)" "-5.0 to +5.0 Volts" "AD1_2_out"
Add an Analog Input Channel
Add an analog input channel with the same device and measurement type Voltage
.
addinput(dq, "AD1", "1", "Voltage"); addinput(dq, "AD1", "2", "Voltage"); ch_in = dq.Channels(3:4); ch_in(1).Name = "AD1_1_in"; ch_in(2).Name = "AD1_2_in"
ch_in = Index Type Device Channel Measurement Type Range Name _____ ____ ______ _______ ________________ __________________ __________ 1 "ai" "AD1" "1" "Voltage (Diff)" "-25 to +25 Volts" "AD1_1_in" 2 "ai" "AD1" "2" "Voltage (Diff)" "-25 to +25 Volts" "AD1_2_in"
Set DataAcquisition Properties and Define an Output Waveform
Set the generation rate to 300 kHz.
rate = 300e3;
dq.Rate = rate;
% Specify a 10 Hz sine wave for 1 second.
f = 10;
totalduration = 1;
n = totalduration * rate;
t = (1:n)/rate;
output = sin(2*pi*f*t)';
Generate and Acquire Data
Generate a sine wave with amplitude 1 V on channel 1 and amplitude 2 V on channel 2 and acquire timestamped data at the same rate.
[data, startTime] = readwrite(dq, [output 2*output]);
Plot Acquired Data
plot(data.Time, data.AD1_1_in, data.Time, data.AD1_2_in); xlabel('Time (s)'); ylabel('Voltage (V)'); title(['Clocked Data Triggered at: ' datestr(startTime)])