Write Continuous Digital Pattern - PXI-6229

[DeonS]

Hi,

I am trying to generate a continuous digital pattern with the PXI-6229 DAQ card. I thought the project named: "ContWriteDigPort-ExtClk" from the shipping examples would be helpful to me. However, I haven't had success in seeing the digital pattern with a scope.

The following is my settings:

-Physical channel:      Dev6/port0/Line0 (to the scope)

-Clock Source:            Dev6/PFI0 (a 1kHz square wave, amplitupde = 5V going in)

-Sample clock rate:    1000.00

I didn't get any errors, and the EXE appeared to be running. Do I need to make any routes? Is it possible to generate the digital pattern with the internal clock? Thank you for the help.

[John_P1]

Hi DeonS,

Welcome to the NI forums!  The ContWriteDigPort-ExtClk example sounds like a good place to start--it accepts data as an unsigned 32-bit integer (one bit per line on Port0 of your 6229).  If you are only interested in line0, that would be Least Significant Bit of the integer.  For example: 1, 3, 5... would set line0 to high, and 0, 2, 4... would set it to low.  You may be doing this correctly already but it is worth mentioning just in case.

Although the digital subsystem does not have its own dedicated clock, you may provide a sample clock from a number of other sources (such as the PFI line you are currently using).  Other options are mentioned in the manual (page 6), but a good description can be found in the following KB:

What Options Do I Have for Hardware-Timed Digital I/O on my M Series DAQ Device?

If you feel that you are doing everything correctly but still not observing any output, you should verify that you are able to generate and measure a digital signal using a test panel in Measurement and Automation Explorer.

-John