Trying to measure 2 channels of 5MHz TTL with E series board

[LoKey]

Using E series MIO board, LabVIEW 7, trying to measure two ~5MHz TTL signals. (sequential is OK)
Do not (can not) use AO channel.
Desire to use signal routing VI (I think) but, examples and description of exactly how to do this is unclear.
An adaptation of 'measure frequency.vi' with addition of 'signal routing.vi' would probably be what I need.
Unless of course there is something simpler.

[gus]

Using the 'measure frequency.vi' uses both counters on the MIO board, so you'll definitely have to measure the signals sequentially. By default, the example will measure frequency on the selected counter's default SOURCE pin (PFI8 for ctr0, PFI3 for ctr1). If you want to use the same example to measure on a different PFI line you can scroll to the left and change the 'Source Specification' cluster to your desired PFI line. All this said, if you have both of your signals connected to different PFI lines you shouldn't need to use the 'signal routing.vi'. After the first measurement you can just change the source selection and run again. Hope this helps.

[LoKey]

Tremendous amount of detail unanswered here.
What do I do about 'cross connecting' CTR0_OUT to CTR1_GATE and CTR1_OUT to CTR0_GATE???
Also, as soon as I actually (simultaneousley) connect 2nd channel of ~5MHz TTL signal to 'other' counters source, counting on previous channel starts to read incorrectly.
To restate...can I actually bring in two ~5MHz TTL signals to simultaneousley connect but sequentially measure their frequencies?
I've tried 'swapping' (reassigning) PFI lines, but to no avail.
My alternative is of course to build a MUX and control it with a DIO line.

[LoKey]

There is NOTHING scrolled to the left on my measure frequency.VI.

[LoKey]

I don't see any 'source specification' cluster.

[gus]

I guess I forgot to ask, but I assumed that you're using traditional DAQ and not DAQmx. And what example are you using? The one I am specifically looking at is installed by default to ..\Program Files\National Instruments\LabVIEW 7.0\examples\daq\counter\daq-stc.llb\Measure Frequency (DAQ-STC).vi.

That example handles all the connections between the two counters on its own. When using this example you shouldn't have any problems with other signals being connected to other PFI lines.

[LoKey]

Ah-ha, I was looking at measure frequency.vi instead of measure frequency (DAQ-STC).vi.
In any event, the code looks understandable, especiall if I use wire to other counters output for the GATE signals.
The problem is...and maybe it's analog? the instant I connect the second TTL signal to (any) PFI connector, it drives the frequency measurement of the previous existing counter (channel) to a 'bad' measurement (usually high by ~10%).

[LoKey]

Gack! Looks like I've got an analog problem and some unstable oscillators here. If I get the oscillators under control I think all will be well.
thanks
~paul

[LoKey]

Nope, still no good.
I tried several different TTL sources, and as soon as I connect a second TTL source (even if from descreetly seperate pulse gen!) to ANY PFI connection, it destroys the integrity (starts to read something higher and unstable!) of the prior (singular) frequency measurment.
Any hints?
Running PCI-MIO-E16-1 card, no other software (or hardware) running. Battery operated pulse gen(s), so no ground loops.
~paul