In the Analog Output Generator Toolbox, how do I trigger the analog output with a external digital signal ?

Hi,

I use the NI-USB 6211 to output a DC voltage signal in ao channel which is triggered by an external TTL signal, imported by PFI0.

I use the function addtrigger to enable the external trigger mode. However, the external trigger signal cannot trig the output. I wonder how to config it ?

The codes are listed below:

d = daq("ni");      
addoutput(d,"Dev1","ao0","Voltage"); 
addtrigger(d, "Digital", "StartTrigger", "External", "Dev1/PFI0");
write(d,OutputVol); % OutputVol is the Output DC Voltage

Additionally, I tried another way to realize the triggering the output, the codes are :

s=daq.createSession('ni'); 
ch=s.addAnalogOutputChannel('Dev1',0,'Voltage'); 
s.addTriggerConnection('External','Dev1/PFI0','StartTrigger')
output=1; % for example
s.queueOutputData(output);
s.startForeground();

It is effective, but the speed, executing from Line 4 to Line 6, is much slower than the method using the first method. How to accelerate it? And what is the difference between the two methods?

Thanks a lot.

[Sakari Vekki]

I had similar issues trying to trigger output signal with external trigger (using NI-USB 6216). Code below seems to do the trick in my matlab app.

                    app.speedOutput =daq("ni");
                    addoutput(app.speedOutput,"Dev1","ao0","Voltage");
        % %         With this configuration writing Dev1/PFI0 high will output preloaded data
                    addtrigger(app.speedOutput,"Digital","StartTrigger","External","Dev1/PFI0");
        
        
        
        %%         Preload output values
                    preload(app.speedOutput,output);
                    start(app.speedOutput);
        %%         app.speedOutput will wait for PFI0 to go high before writing preloaded values

So instead of using 'write', try to preload the data and use 'start' command. Output signal and incoming trigger are perfectly synchronized this way.