09-29-2009 11:01 AM
I'm trying to measure the frequency of a digital input on my 6034E card, but I need some filtering/de-bouncing which is not available in hardware. I've attached a screenshot of the approach I've taken (which may well be totally wrong - I've not dealt with measuring digital signals before). Before this approach I had tried using a counter to measure the frequency, which kind of worked, but the signal was very noisy. Anyway, I seem to be stuck at 1st base with this, as I get an error from the DAQmx Read node (code 200014) which says the terminal cannot appear multiple times within a single digital input task. I've checked the examples, and it doesn't look obvious to me what I'm doing wrong - can someone help me out please?
Solved! Go to Solution.
09-30-2009 01:58 AM
First impressions show me that what you are attempting looks correct in theory, the error is in relation to your channel setup. I notice you have a "task" and "line" input, the task should exist under Measurement & Automaticion Explorer (MAX) and contain all settings for the digital channel therefore the line input shouldn't be required. I can also see that you DAQmx Read has no timeout wired to it, I think it should automatically accept -1 in this scenario but may be worth wiring that in to be sure.
If that doesn't help I'd appreciate a copy of your code and I will try it out on my system.
All the best,
09-30-2009 06:58 AM
Just having the lines input, and deleting the task input helped. Then realised my hardware limits what kind of timing I can have (only On Demand). Finally worked through a series of error messages and I now have some code ready to test on real signals.
Thanks for your help,
09-30-2009 08:09 AM
You're more than welcome, I'm glad its up and running for you!
All the best,