How to output analog signals after analog input voltage exceeds 5V?

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W Joey 2015-7-18

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此问题的直接链接

https://ww2.mathworks.cn/matlabcentral/answers/230330-how-to-output-analog-signals-after-analog-input-voltage-exceeds-5v

编辑： W Joey 2015-7-18

Hello everyone, I am currently using the analog input and analog output channels of NI DAQ devices with session-based interface. Now i want to output a pulse for 2 seconds whenever the PC detects a input voltage exceeding 5V, and then input restarts. Here's my code,

 si=daq.createSession(‘ni’）;
si.Rate=10;
si.DurationInSeconds=10;
si.addAnalogInputChannel('Dev1','ai0','Voltage');
si.Chennels.InputType='SingleEnded';
lh=addlistener(si.'DataAvailable',@pulseoutput);
si.IsContinuous=true;
si.startBackground();
function pulseoutput(hObject,eventdata) 
if any(eventdata.Data>=5.0)
stop(hObject);
s=daq.createSession('ni');
addAnalogOutputChannel(s,'Dev',0,'Voltage');
t=0:0.001:2;
w=4;
outputSignal=rectpuls(t,w)';
queueOutputData(s,outputSignal);
s.startForeground;
rerun();
end
end
function rerun()
si=daq.createSession(‘ni’）;
si.Rate=10;
si.DurationInSeconds=10;
si.addAnalogInputChannel('Dev1','ai0','Voltage');
si.Chennels.InputType='SingleEnded';
lh=addlistener(si.'DataAvailable',@pulseoutput);
si.IsContinuous=true;
si.startBackground();
end

Whenever voltage exceeding 5V is detected, a pulse will be generated successfully, but the analog input will not restart again and error message appears'Timeout expired before operation could complete'. Any suggestions on how to correct the codes? Thank you in advance.