Something about counters???

[Peter_02]

Hello,

I have some question about the counters on the 6602 card.
In my application are signals connected to the gate pins of some counters (0,2,4 and 5).

I want to perform some measurement on these signals.

But some things are still ambiguous to me, 'coz I'm new to LabView.

I have set the source-settings to 20Mhz. So I have an internal timebase.
But what does mean the PFI-Line settings in Source Spec.? (now it is default)

And what does the gate-settings mean?

I think the PFI-option is the PFI-line I want to measure with the counter.
And the polarity is on which edge (rising or falling) the counter starts to count.

But what if I want to trigger the counters to start simultaneously?
I think I have to choose the same ga
te on all counters therefor, if I'm right???

But how can they count their own gate signals, so the signal on the PFI-lines? Or must I use an extra trigger?

Where can I find some information about counters and their functionality and and maybe an easy example of starting/stopping
two or more counters simultaneously (triggering)?

Thanks in advance

Peter

[RIO-Todd]

Peter,

To use the internal 20 MHz timebase you will need to set the source selection to internal timebase AND set the clock to 20 MHz. If the source selection is in the top position of PFI Line AND is set to default the counter will look at the counter's source pin of the device for the source signal (pin 7 for counter 1, pin 34 for counter 2, etc). Take a look at the user manual for the NI 6602 for the entire pin-out of the device.

To start two counters at the same time, you can configure a start trigger for two counters. The example program linked below illustrates how to trigger multiple counters. I hope this helps.

Simultaneous Triggered Buffered Event Counting with Two Counters
http://venus.ni.com/stage/we/niepd_web_display.DISPLAY_EPD4?p_guid=B4
5EACE3F0C356A4E034080020E74861&p_node=DZ52325&p_submitted=N&p_rank=&p_answer=&p_source=Internal

[Peter_02]

Hello Toddd,

thank you for your answer. It helps.

Peter