Any ideas why '1 sample on demand' gives so many errors using Signal Express on simple analog input ? It would be nice to choose this option, run continuously, and have the data view act as a simple strip chart.
Thanks for your input - I'm using CompacDaq 9137 modules and Honeywell pressure sensors ( not transducers ). The 9137's are in full bridge mode as required by the sensors. The error is ( sorry I don't have it right in front of me ) basically that 1 sample on demand is not supported by this configuration. However, the other two modes ( continuous and N Samples ) work fine. What I really want to do is just sample 1 on demand and have the data view act as a simple strip chart. We all find that Signal Express is cumbersome and not very intuitive. We were hoping to just do this quick-n-dirty in Signal Express, but can always go right to LabVIEW, as we're well experienced there.
I assume you mean you are using the 9237. You are correct that this device does not a support a single sample read. This is not because of SignalExpress, however. The 9237 has a delta-sigma ADC that continuously samples with an oversample clock and has a built in integrator circuit that produces the measurement that is returned through software. The closest to single point you could get in your application would be to take a 2 point finite measurement and throw away one of your data points. That should be trivial to do in LabVIEW, but not so easy in SE.
Thanks Dan, kind sir... that answers my question. And oops - yep, I did mean 9237. It's funny - no matter what I seem to do ( I've been using LabVIEW for nearly 15 years heavily ) I always seem to be the one who runs into these dang quirks ! I'm always at a loss for words - how come something that should be so simple is causing me problems ?!?! Anyway, thanks for the info. I'll stick to ol' reliable LabVIEW.
