digital stimulus-frequency response: Need to drive with digital output trigger. Using counters for response.

[ZAPS]

I need to drive stimulus-response with a software driven digital trigger and NI-TIO counter based response. No analog I/O is really relevant, although I have a PCI-6035E multi-function DAQ as part of my gear. I intend to use the analog, but its timing is non-critical and can be software timed.

The real trick is that I want to set the basic timing of the system (in the range of 1 - 50Hz) from the timer0 on the 6035E. This signal needs to be replicated to drive a trigger pulse and to route through RTSI (or a PFI) to trigger frequency counts using the four possible groups of counter/timers on the 6602.

What I need is:
while( enabled )
{
Repeat at (
software controllable rate = 1-50Hz)
{
Trigger Sets a PFI line for 10-20us
same trigger sets an RTSI line
- Software Set Delay (usually zero)- stable is more important than the delay time!
Count for software set time on 4 counters
analog samples
Post-process
}
}

I want to do this in LabView. I have checked out the Advanced sychronization demos online, but the examples all use analog triggering and buffered digital I/O. This doesn't really address what I need to do.

I have made some failed attempts which relied on software to sync up the trigger and the response frequency acquisition. This is definately flawed. I need to start the counting right after setting the digital output trigger, and stop the count after a fixed interval for frequency calculation.

I am having trouble working through the signal routing to get the timing to trigger off the digital stimulus output pulse.

Any help would be appreciated
.

Thanks,

Joe

[bman]

Joe

What are you using the trigger from the 6035E for? I do not know what you mean by, "to trigger frequency countes."

If you are having problems just routing the signal to the 6602, here is a vi that shows you how to route a signal through the RTSI cable to use as the source of a counter.

Brian

[ZAPS]

The 6035E trigger is intended to set the overall repetition rate for this.
This is a red herring however. The real trick is getting a digital pulse to be immidiately followed by a frequency count on four seperate counters. This can all be done on the 6602 in all truth.
Pulse -> count edges -> calculate freq