NI-DAQMX and logic signals generation with external clock

[zhal]

Hi everybody

LABVIEW 8

NI-DAQMX 7.2

PXi system w/ PXI-6251 DAQ

I'm a french student and i have a problem using LABVIEW and nidaqmx.

l'm actually designing a board to generate PLC signals. Acquiring signals (Analog/Numeric) is not a problem for me, every thing is fine for this. But i need to generate a 24 bits word to configure a chip on a board, with an external clock given by the chip itself.

Actually i read a file with boolean values and i have a table with them. I would like to change the value on the line at every rising edge of the external clock. But i have errors like "the buffer is to small" and other things like that.

Does anybody have any tutorial that could help me ?

Ps : I took a look on the exemple furnished with LABVIEW (generates a square signal according to an external clock on PFI1), but i'm unable to change the square signal by something else.

Pss : LABVIEW is an really interesting software but they are wrong when they say it's intuitive 😛

thanks a lot

[Ludovic R.]

Hi,

Here is a good place to start with NI-DAQmx : Getting Started with NI-DAQmx: Main Page.

Then you should take a look at "Cont Write Dig Port-Ext Clk-Non Regeneration" example in LabVIEW. This does what you described in your post.

Regards,

Ludovic R.