What a curious idea...  It seems like you need some sort of shift
register to save the count when you MUX the gate.  Otherwise you are not
really timesharing the counter you are just doing a bunch of little
counting jobs with differnet inputs and outputs each time.

My first thought is that a 6602 card is going to be cheaper than the time
to kluge this in software, and probably kluge with some external hardware
as well.

Off the top of my head...A couple of fast (solid state to eliminate
contact bounce) relays might allow you to shift from one input source and
output destination to another with a digital output as a control.
 Reassigining PFI lines sounds very slow to me since that is likely done
in the counter config vi and you are starting and stopping the counting
routine completely.   Maybe the more advanced vis will allow some
trickery.

Unless you have used the counters a lot, you will find a steep learning
curve (I am still at the foot of the slope).  There is little
documentation and few examples that illustrate tricks and techniques (I
have not delved into this for a year or so, maybe LV7 has more neat
stuff...)  I would go immediatley to the tech support people to see what
they think.

Some comments about the actuall speed you need to count and MUX would be
useful to those offering advise.

Mike

 -----Original Message-----
From: Brumfield, Anne [mailto:[EMAIL PROTECTED]
Sent: Wednesday, March 24, 2004 11:55 AM
To: info-labview
Subject: multiplexing counters



Has anyone ever tried to alternate the PFI lines at the gate of a
counter (rapidly) in order to gather data from more that one device (PWM
output)??

Limited to 2 counters, I can only get data from the 2 outputs of a
single device. Trying to stretch resources here and just curious if this
particular topic has ever come up??

With pwm proliferating, thought it might have.... Appreciate any input!

Sincerely,

Anne Brumfield


Reply via email to