06-13-2006 10:01 AM
06-13-2006 12:31 PM
06-14-2006 05:01 AM
Chad,
Answers to your questions:
1. In my original query i was using NI-SWITCH but have also tried out the NI-DAQmx Switch API to try and get around my problem.
2. Trigger line set-up is as you stated (plus sink switch in there as well but i simplified things in the query).
3. NI-DAQmx 8.1 and NI-SWITCH 3.1
Suggested Solutions:
1. I don't see how this solution saves relay life on the source switch, surely this still requires a channel change from every switch before the trigger is sent to the DMM? Might have completely mis-understood this solution...
2. I think this solution will probably do what i want, will crack on and test it out and let you know. I didn't relise from the documentation that it was possible to have multiple switches in the same scan list.
Cheers for your help,
Leon
06-14-2006 07:50 AM
Hi Leon,
I do hope the second solution works for you!
The first solution would only require a channel change on just one switch (DMM switch - the switch that changes each measurement) before the trigger is sent to the DMM. In this scenario, you could think of it as handshaking between the DMM and one switch. The other two switches would synchronous scan, moving to the next scan list entry whenever the DMM's measurement complete is sent, but these two switches (because they may or may not change each measurement) do not send a scan advanced output. The handshaking switch is the only one with the power to tell the DMM to make a measurement.
Good Luck!
Chad Erickson
Switch Product Support Engineer
NI - USA
06-14-2006 09:42 AM
Chad,
The second solution works exactly as i needed. And think i prefer the greater control over which switch acts first.
Think i understand your first solution now. For this would the scan list for the source be as i put in my original post, with the lone debounce ';' commands signifying no channel change?
Thanks for all your help,
Leon
06-14-2006 09:57 AM
Hi Leon,
Good to hear you application is working!
In response to the first suggestion, you would be correct to place dummy entries ';' in the scan list. Exactly.
Chad Erickson
Switch Product Support Engineer
NI - USA