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Error -200462 OUTPUT BUFFER IS EMPTY

To all,

 

I am new to labview so please be patient. Thanks.

 

Basically, I am trying to make up a code that will synchronize several different testing apparatuses (cameras, force sensor, testing machine).

 

I am using a  DAQ USBX-6341 board.

 

I am using a counter terminal to generate a digital pulse that will trigger the cameras, force sensor and testing machine all to start at the same time.

 

I have the force sensor hooked up into the analog in channel/port 1.

I have the cameras hooked up into the digital p0.0 channel/port.

I have the testing machine connected via COM5.

 

When I press RUN, the force sensor and testing machine work fine, but I get the following error message:

 

" ERROR  -200462   

Generation cannot be starte because output buffer is empty. ......"

 

I think the problem is the camera is a digital output port and that the trigger signal does not support this.

 

If I change the digital output to a digital  input, the output buffer problem goes away.

 

I do not want to collect data (such as a wave) from the inport. I just want to tell the camera to start collecting data in its respective software.

 

Does anyone have an idea about what my error is and how I can get around this? My labview is very close to working!

 

Thanks

 

gcass

 

 

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gcass,

 

It sounds like your project is coming along!  It sounds like you are trying to generate a digital pulse to activate your camera, is that correct?  If so, you might consider using a counter to generate this pulse instead of a digital output.  You can look at the Gen Dig Pulse example under Hardware Input and Output » DAQmx » Generating Digital Pulses in the LabVIEW examples.

 

As far as your current error is concerned though, it sounds like you are trying to start your DAQmx task before you write any data to the buffer.  In the case of a finite generation, you should add your data (in this case, a single pulse) to the buffer with a DAQmx Write before the DAQmx Start Task.  I hope this helps!

 

Regards,

Trey C.

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Yes, I want to start the cameras on a digital pulse. Attached is a picture of my current code and a documentation of it.

 

Basically, I have a counter terminal (crt1) creating a digital pulse and that outputs to another temrinal (crt0) which is used as a clock and trigger source for my cameras and force sensor.

 

The error that I am having involves routing the digital pulse created by the counter into the digital output.

 

I simply want the cameras to start on a digital pulse. I keep getting that buffer error though.

 

I will try the daq write, but I dont have data coming in so it wont work.

 

Do you have any advice?

 

Thanks

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Error with Digital OUTUT.JPG

 

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gcass,

 

Can you tell me which Start Task this error is generated from? You can use highlight execution (the lightbulb in the top left) to watch the code run and see what throws the error.

 

On your bottom task, the Digital Output, you will need to write data to the buffer before starting the task.  You can see an example of this under Hardware Input and Output » DAQmx » Digital Generation » Cont Write Dig Port - Ext Clk.vi.  As you will see in this example, the DAQmx Write is used to determine what data is generated on that port.

 

Regards,

Trey C. 

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