Hello Mark, thanks for your fast response: >Your requirement includes a "closed loop" control and you imply a need >for rapid and accurate data from the sensors. You specify a max of >250ms to read 4 DS18B20 sensors. One closed loop control shall be around 250ms, so the four loops can also be measured at the same time.
> 1. The conversion time for the DS18B20 varies depending upon > resolution. Assuming your control requires the highest resolution (12 > bit) the best conversion time you will get is 1000 ms. no, I guess 0,5°C or 0,25°C shall be far enough and therefore I'm on 93..187ms > 2. OWFS can perform a "simultaneous" conversion on a given net > (simultaneous=1). This means all temperature sensors on a bus will > convert with a single one wire API call. But to take advantage of this > you must be certain that all four sensors are on the same physical net. Oh, yes, that's it. All sensors are powered, so this should work. > 3. I assume that a simultaneous conversion, or any OWFS temperature > conversion, is done for the highest resolution (Paul might weigh-in > here). As such, it can be assumed that any conversion of DS18B20's will >take about 1 second to complete. buuuh - I hope I can use it with 9-bits as well... So I try owcapi now. Thanks for your comments Achim -- View this message in context: http://old.nabble.com/different-access-performance-tp32230443p32235597.html Sent from the OWFS - Dev mailing list archive at Nabble.com. ------------------------------------------------------------------------------ uberSVN's rich system and user administration capabilities and model configuration take the hassle out of deploying and managing Subversion and the tools developers use with it. Learn more about uberSVN and get a free download at: http://p.sf.net/sfu/wandisco-dev2dev _______________________________________________ Owfs-developers mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/owfs-developers
