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Error when generating pulses from NI USB 6501

I'm new in LABVIEW.  I'm working on the following LABVIEW code to control a motor. I have connected the port 2.7 for the ctr but I still get the error as: 

I/O type of the physical channel does not match the I/O type required for the virtual channel you are creating.

Physical Channel Name: ctr0
Virtual Channel Name: Dev1/ctr0
I/O Type Required for Virtual Channel: Counter Output

Moreover, when testing via LED for pulses, the LED glows continuously. Even when my LABVIEW simulation is not running. See the image below if you'd like to see the connection.

Please help.

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Counter measurements: Falling edge counting


So this thing only has one counter and it's only good as an input, not as an output. So if you just want to count things on the falling edge, you can get this to work by correctly configuring the task as a counter input (CI) task. Otherwise, you'll need another device. Either one with buffered digital or analog outputs, or one with a better counter (see for instance, or one with an exposed clock source.


Depends on your application.

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