Pulse input to DAQ PCI-MIO-16XE-50

[Doug Clauder]

Hello,
I have seven analog
inputs which vary slowly and need to be sampled at 10Hz max. I have one pulse
input which changes
at 2000Hz maximum. The pulse input needs to be converted to a frequency value.
I intend to
use LabView to view the data as it changes, and store the data at one second
intervals in CSV format
on the hard disk. I need to know what DAQ card to use.

I am looking at the PCI-MIO-16XE-50, but I have two concerns:
1) With its overall sampling rate of 20kHz, that's 2.5 kHz per channel (since
I have 8 inputs), or can I individually adjust the sampling rates on the
channels?
If the pulse train is pulsing 2000 times per second, I need at least 4kHz
sampling on the channel.
2) My understanding is that thi
s board uses system ram to store the data.
I would prefer to have the
board calculate the rate of change on the pulsed input and allow me to store
the result once per second,
because I am concerned about burdening the host (Windows 95) with the rate
of change calculation. Does this
mean I need a high-end board? If so, is "burdening the host" really an issue
in this case (dedicated 350MHz IBM PC)?

Please respond via email.
Thanks,
Doug Clauder

[Dmitry Rozmanov]

Hi,

You can do this with XE-50.

Use 7 AI to meassure your analog inputs.

And frequency you can meassure with two counter, it is standard task for
them. The card has two counter this is what you need, but if there is
another such input so you will need to get another pair.

It is implemented like this:
- first count generate a pulse of known period, say, 0.2 sec, and this
pulse is connected to start/stop pin of the second counter

- second counter counts pulses from your sourse during period first
counter feed to him.

- then you get number of pulses for the given period, in our case for
0.2 sec, N/0.2=>F. Bingo. And card do everithing


Best regards.

---Dmitry.

Doug Clauder wrote:
>
> Hello,
> I have seven analog
> inputs which vary slowly and need to be
sampled at 10Hz max. I have one pulse
> input which changes
> at 2000Hz maximum. The pulse input needs to be converted to a frequency value.
> I intend to
> use LabView to view the data as it changes, and store the data at one second
> intervals in CSV format
> on the hard disk. I need to know what DAQ card to use.
>
> I am looking at the PCI-MIO-16XE-50, but I have two concerns:
> 1) With its overall sampling rate of 20kHz, that's 2.5 kHz per channel (since
> I have 8 inputs), or can I individually adjust the sampling rates on the
> channels?
> If the pulse train is pulsing 2000 times per second, I need at least 4kHz
> sampling on the channel.
> 2) My understanding is that this board uses system ram to store the data.
> I would prefer to have the
> board calculate the rate of change on the pulsed input and allow me to store
> the result once per second,
> because I am concerned about burdening the host (Windows 95) with the rate
> of change calculation. Does this
> mean I need a high
-end board? If so, is "burdening the host" really an issue
> in this case (dedicated 350MHz IBM PC)?
>
> Please respond via email.
> Thanks,
> Doug Clauder