How can I output an analog signal while acquiring background data?

Question

Chris Carlson 2017-7-25

0
链接

此问题的直接链接

https://ww2.mathworks.cn/matlabcentral/answers/350250-how-can-i-output-an-analog-signal-while-acquiring-background-data

I am trying to acquire data while also sending an output signal to a external circuit using the DAQ toolbox. How can I do this? Ideally the output signal would be immediately sent out as soon as a certain condition is met in the data.

Below is my code:

s = daq.createSession('ni');
% 2 inputs and one output
addAnalogInputChannel(s,'Dev1', 'ai1', 'Voltage');
addAnalogInputChannel(s,'Dev1', 'ai2', 'Voltage');
addAnalogOutputChannel(s,'Dev1', 'ao0','Voltage');
s.Rate = 83000;
% event listener
lh = addlistener(s,'DataAvailable', @(src,event) perturb(event.TimeStamps, event.Data));
% max size in data buffer
s.NotifyWhenDataAvailableExceeds = 2000;
s.startBackground();

%% function that is called by event listener

function perturb(curTime , data)
    plot(curTime, data(:,1), curTime, data(:,2));
      %if some condition in the data is met, output analog signal
      if (data(1300,2) < 0)
          % immediately output signal here:
          % my attempt:
          %outputSingleValue1 = 1.5;
          %outputSignal1 = [zeros(1,520) outputSingleValue1*[0:0.1:1 1:-0.1:0] zeros(1,4000)];
          %queueOutputData(s,outputSignal1');
      end
end