Count the number of Pluses Generated

[raghavendra]

we are using the pxi-6602(counter/IO) along with SCB-68.
the problem we are encountering is that,we want count the
number of pulses generated.

we are using the counter0 and generating the
pluse, using the example VI Genrate Finite pulse(TIO).VI
which we are able to capure at the CTR0-out.

we want to count the number of pulses generated at
CTR0, so we have connected to the gate of CTR1
and we are running the example vi Measure Pluse NI(TIO)

we are not able to count back the number of pulses generated.

can any one guide us ....

are we heading in the right

1)is it possiblt to count and measure the number of pulse generated.
2)is it neccessary to specify the PFI line in the measuring/counting.
3)output of one counter is connected to gate of the other counter to measure. is it right
4)since this is the first time we are using counter/timers, please guide us, about connecting the
  out and source and gate in scb-68.

thanking you

rags

[Kevin_Price]

I'm not at a LV PC now, so I can't look at the examples you mentioned.  However, the primary problem is that when you generate a finite pulse train on Ctr0, the DAQ driver makes use of Ctr1 to control the # of pulses generated by Ctr0.

Because you have a 6602, you can simply measure the # of pulses with any of the other 6 counters on board.  Ctr1, the one you might naturally think to use, is the only one that won't work.

The method will depend on whether you're using traditional NI-DAQ or DAQmx.  The example names sound like traditional NI-DAQ, so the simplest thing is to actually wire from Ctr0 output to your measurement Ctr's Source input.  Each of the Ctr's has a different PFI pin as its (default) Source input.   Summarizing your questions:

1. Yes it's possible to measure # of counts generated by Ctr0 with any Ctr EXCEPT Ctr1.  (Note that if you generated continuous pulses with Ctr0, you could then use Ctr1 to count them).

2. It's possible to specify the PFI line for counting pulses.  If you physically wire to the default Source input, it won't be necessary.

3. Output of one counter should be connected to the SOURCE of another counter.

4. Ctr0 Out should be wired to, say, Ctr2 Source.  Don't have hw here to be able to identify pin #'s.

Final note: under DAQmx, you wouldn't need any wiring.  You can programmatically tell any measuring counter to count the edges on any other pulse-generating counter.

-Kevin P.