Generating pulse trains independent from my PC

[FullyBeginner]

Hallo,
I want to ask , how to generating a digital pulse with counter gate from my Labview 7.0 and that signal should be independent from my PC (My tutor said, even i shut down my PC , the signal will always be generated). I use Labview 7.0 , DAQ card , and Shielded I/O Connector Block SCB-68 . And which PIN should i use in that connector?
Thank you very much for any help.

Jimmy

[Bill B]

Hello Jimmy,

Thank you for contacting National Instruments.

You can easily generate a pulse or a pulse train from your DAQ board using LabVIEW 7.0. If you choose to generate this output on counter 0, you will most likely need to connect to pin #2. If you choose to use counter 1, you will most likely need to connect to pin #40. You can connect to any of the DGND signals for a ground reference. These are pins: 35, 36, 4, 39, 9, ...

In order to actually program your board, I recommend that you use our DAQmx driver. I have attached two example programs below. One demonstrates how to generate a pulse and the other generates a pulse train. You can find these examples on your machine by going to Help >> Find Examples >> Hardware Input and
Output >> DAQmx >> Generating Digital pulses

You will not be able to have the signal be independent of your PC. First, the board must be programmed by your PC to start and stop the output. Secondly, your DAQ board is powered by your PC power supply. If you turn off the PC, you will effectively turn off your board.

Let me know if you need any additional assistance with this issue.

Regards,
Bill B
Applications Engineer
National Instruments

[FullyBeginner]

Hallo Bill, Hallo all ,

Thank you very much for the answer.
I have tried your suggestion (with DAQmx),but unfortunately when i click on stop (red buttom), the signal will be terminated.

So i use another method and i attach that program. With that Program i just need to run once and the signal will be generated and even i click on red buttom (stop), the signal is still there (So far i dont close Labview main window).

I need to generate 2 signal. The problem is that both signal dont start at the same time (Signal 1 has delay about 0,7 ms).I connect Pin #2 and #36 for counter 1 and pin #40 and #36 for counter 2.

I have seen in internet , that one should use PFI or trigger to start it simultaneously ,but I can not find a good tutoria
l about that.
Can somebody help me with this problem,
Thank you very much for your time.

Yours sincerely
Jimmy

[Bill B]

Hello Jimmy,

I have attached an example program which uses our DAQmx VIs rather than the Traditional VIs which you used in your example VI. The example I attached will allow you to set the frequency of each counter ouput signal and uses PFI0 as the trigger input so that you can start both pulse trains at the same time. You simply need to connect a TTL trigger signal up to PFI0 and when a rising edge is received, the pulse train outputs will be triggered.

Let me know if you have any questions about this example.

Regards,
Bill

[FullyBeginner]

Hallo Bill,

Thank you very much for your help. But sorry that it is not so clear for me.
I generate signal 1 by connecting Pin 2 to Pin 36. And signal 2 by connecting Pin 40 to Pin 36.
And how should i connect the trigger? Pin #11(PFI0) to where?
Thank you very much.

Regards
Jimmy

[Bill B]

Jimmy,

You will need to connect an external signal that produces a trigger pulse to pin #11 (PFI0). This pin will receive a pulse that you generate and when it receives the pulse, it will trigger the output of the pulse trains on pin 2 and pin 40.

Regards,
Bill B