General questions about USB6009

[drj]

Hi:

I have the following questions regarding the USB 6009.

1. The green LED on unit always flashes at a constant rate as soon as I plug it into the PC's USB port. This occurred from the first time I connected it to the PC. Is this normal?

2. I have a photoelectric sensor w/ a electromech. relay. I want to set up a timer in my VI that starts when the beam is blocked .
I was planning the following:

a. Use the 5V Power Source on  the 6009 and run it to the relay.
b. Connect the NO  (normally open) contact to the PF10 Digital Counter
c. Once the beam is blocked on the sensor, the relay switches from the NC contact to the NO contact--thus sending 5V to PF10, and starting the timer.

Is this the best way to do this? Or should I try to use a Digital Input instead of PF10?
Are there any example of this anywhere?

3. How do I turn "on" the 5V Power supply or even the 2.5 V ref. signal on the 6009. I tried  measure the voltage on the 2.5 V and 5 V ports w/ a voltmeter (relative to the GND next to the 5V channel). But I keep getting 0 V on either of them. I can't find these ports in the DAQ assistant either.

I am using LabVIEW 7.1

Thanks!

[Laura F.]

Hello drj,

1.  The flashing LED is normal. 

2.  The way you have proposed to count will not work because of the functionality of the counter.  Please see this excerpt from the USB-6006 User Manual:

You can configure PFI 0 as a source for a gated invertor counter input edge

count task. In this mode, falling-edge events are counted using a 32-bit

counter.

What this means is that you can only increment the count in the counter on a falling edge of a signal.  From what I understand that you are trying to do, you would be better off to use a counter's gate to set up a pause trigger, which is functionality not supported by your device.  Instead, you should probably use a digital input to start a software timer when the input changes.  You can see the LabVIEW Example Finder (Help >> Find Examples) for examples of how to do digital input with your device.  In particular, navigate to Hardware Input and Output >> DAQmx >> Digital Measurements >> Read Dig Chan.vi

3.  As long as your 6009 is connected to your computer, you should be able to read +5 or 2.5 V on terminals 30 and 31.  If you are not getting this voltage, try connecting to a different USB port or even a different computer in case it is a problem with the port you are currently connected to.

Please let us know if you have additional questions.

Hope this helps!

Laura