Dual pulse generation

[ianfirth]

I am trying to generate a dual pulse signal 90 degrees out of phase. I am wanting to use a compactDaq digital output card if possible, as I also want to be able to drop occasional pulses in each pulse train. I can generate a single train with missing pulses, but I need to have 90 out of phase signals, and it appears all the digital cards are grounded to the same place. I have seen DI cards have a differential input versions, is a differential version available for the DO units.

Ian

[Kurt_NISalesEngineer]

Hi,

With regard to the first query - you should be able to programmatically define two signals 90 degrees out of phase and even like you describe drop a pulse in the signal by, for example flicking a switch on the front panel. Are you working with LabVIEW? If so which version - have you coded up a VI that you can post to this discussion forum board for us to be able to help you a little further? There are some kool examples that are shipped with LabVIEW if you are looking for a starting point. In LabVIEW go to > help > find examples.

The following example code might be helpful for you. In this example it demonstrates how to perform correlated digital generation on a cDAQ module using an internal counter as a sample clock.

http://zone.ni.com/devzone/cda/epd/p/id/5086

Unfortuantly we don't sell "differential" DIO cDAQ modules at the moment. The compact DAQ online advisor shows we only sell SE DIO cDAQ cards, please goto: http://ohm.ni.com/advisors/compactdaq?cmd=NiCfgCdaqIntroPage:Continue

Kind Regards,

Kirtesh Mistry
National Instruments UK & Ireland

[ianfirth]

Kirtesh

I have at present fieldpoint devices as well as a PCI 6534 and labview 7. I am looking into purchasing the new usb compact DAQ, for benchwork and I can simulate everything that I require other than the dual pulse which I really require to be at a differential output. I wanted to see if it was possible before buying new hardware and Labview 8.2 Pro, and as such had a visit from David Baker the other day, giving me a demonstration. As your range is increasing at a fast pace  my question  was wondering if you had a differential DO in the pipeline, but not yet released.

Ian

[Kurt_NISalesEngineer]

Hi Ian,

I'm wondering what you are hoping to do with the overall application. Can you tell me more about the application itself and your objectives? I.e. why do you need to have differential DIO? Did you want to have a varible digital output voltage different range? Are using TTL? Have you considered generating a logic signal 0/1 type signal via analog output lines?

Unfortunatly I can't disclose any details about forthcomming products that are to be released and yes you are correct we do have quite an impressive portfolio of products and it just gets bigger and better - always worthwhile to keep in tune with our website for new product releases.  

Kindest Regards,

Kirtesh Mistry

Applications Engineer

National Instruments UK & lreland.