On Fri, Jul 8, 2011 at 11:41 AM, Paul Alfille <[email protected]> wrote: > Hi Pedro, > > I looked at the HobbyBoards site and I think the humidity sensor is HIH-4000 > based. > http://www.hobby-boards.com/catalog/product_info.php?cPath=24&products_id=54 > > I presume you are reading the HIH4000/humidity property.
I am indeed reading that. > My thought is to figure out which value is causing the sprious readings. The > calculation requires > VDD VAD and Temperature. > > Possibly putting in a line line: > printf( "%g,%g,%g,%g\n", VAD, VDD, T, OWQ_F(owq) ) ; > > before the return statement > File: owfs/module/owlib/src/c/ow_2438.c > Subroutine: FS_HUMID_4000 > Line 372 > > // temperature compensation > temperature_compensation = 1.0546 - 0.00216 * T ; > OWQ_F(owq) = humidity_uncompensated / temperature_compensation ; > > + printf( "%g,%g,%g,%g\n", VAD, VDD, T, OWQ_F(owq) ) ; > return 0; > } > > And running owserver in foreground piped to a file. > > We'll get a CSV file that is easy to read in any spreadsheet. (Maybe some > fancy gnuplot script would do it too). > The columns will be VAD, VDD, Temperature and Humidity > Plotted out, it should be obvious if the outlier humidity readings > correspond to any outlier voltage or temperature readings. I can definitely try and do that. Shouldn't take too long to get something. For some reason with this setup I'm getting a lot of these. One initial thought is that it may be a problem with the temperature as I was getting some strange "85ºC" readings on first connection of these sensors. Another strange thing with these sensors is that they include both a DS2438 for the humidity reading and a DS18S20 for the temperature. The DS2438 includes a temperature reading but they don't seem to agree. A quick read just now gives me: DS18S20: 24.375 DS2438: 25.7188 The difference is substantial. > Perhaps the reading needs a delay for the line to settle. I've had the same problem, only less serious, with at least a pressure sensor and another humidity sensor from AAG. That's why I ended up building the outlier removal stuff in saal. Do you think those are individual bugs and not something generic? Pedro ------------------------------------------------------------------------------ All of the data generated in your IT infrastructure is seriously valuable. Why? It contains a definitive record of application performance, security threats, fraudulent activity, and more. Splunk takes this data and makes sense of it. IT sense. And common sense. http://p.sf.net/sfu/splunk-d2d-c2 _______________________________________________ Owfs-developers mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/owfs-developers
