deepsilence

I won't argue with an NI Eng... ...but I am pretty sure I have used the older cDAQ (with M series board and therefore STC2-based timing) and inserted a module with inbuilt timing and exported the clock so I can do Buffered Counter Input on Slot 5/6 with a DIO module.

I implemented a plug-in for Signal Express as it didn't allow Buffered Counter Input even though MAX/LabVIEW support it.

I thought it would have been similar with Buffered Counter Output.

I am not sure if you can set something up like that with the hardware you have, but I think that is a workaround for STC2-based CompactDAQ?

Thanks, jgcode.

I will give it some thinking.

I got official reply from NI engineers:

Buffered counter operations are only supported on STC3-based devices (i.e. X Series and CompactDAQ).

Your M Series is an STC2-based device and so does not have support for buffered counter outputs. Any updates to the counter output characteristics on this board have to be software-timed.

If you do need deterministic counter updates, you could either switch hardware or implement a workaround using the digital output with a pre-defined digital waveform.

Also look at the following example for reconfiguring pulse frequency during a finite task, it would be useful if you want an exact number of pulses but don't need the updates to occur deterministically.

https://decibel.ni.com/content/docs/DOC-6109

Thanks guys

Hey, JG,

yep, i've searched through the examples. I didn't find any one using Counter Write NSamp.

Hi,

I wrote the following program trying to output a series of 100 samples of pulses whose frequency is ramping up from 10 to 100. Device: PCI-6229.

I got error: -201291: Pulse specifications cannot be written to a finite counter output task on this device.

I do not know what was wrong.

Basically I have no idea how to use the vi, DAQmx Write: Counter Freq NSamp 1Chan or NChan

I do know how to use property node to change frequency and duty cycle on the fly. However, In this particular post I would like to know how to use this NSamp VI.

Thanks.