On Sun, Jan 10, 2010 at 11:10 PM, Paul Alfille <[email protected]> wrote: >> Some sensors are powered some are not. > > > That might be a problem. There isn't enough current in the data line to fuel > simultaneous parasitic-powered temperature conversions.
It is not really a current problem. The data line must be held high during all the temperature conversion. So it is not possible to access any other device during the conversion >> >> My big problem I had: I don't have the /simultaneous directory when I >> "ls" in the owfs directory. But when I do 'ls simultaneous', the dir >> exists! >> > > The directory is only listed when there is a relevant device on the bus. > (But the directory is valid, just hidden). I was perplexed until I saw in > the next section that you have a DS2409 microhub. > So this is not a bug? Maybe it should appear at each hub "aux" and "main" dirs? > Thanks for the report. Sounds like a bug. Thanks for your support. I would also have a feature wish concerning this. As I said, I have some sensors that are not powered but all alone on their own bus segments behind the hub. Is it possible to make an asynchronous read? This means make simultaneous reads but between distincts hub segments, as if there were several 1 wire bus controlers. I don't know if it is electrically feasible, but I think it should. Maybe it could look something like a temperatureReadTrigger in each sensor dir. This would start the conversion process, and lock the bus segment until the conversion ends. During this time, other hub's bus segment should remain accessible and it should be possible to start other temperature conversion on these other bus segments. A read in the corresponding temperature file would wait until the required conversion time is finished. This should work even if sensors are not powered. But if they are powered, it should be also possible to trigger several simultaneous sensor read in differents hub's buses. What do you think about this? Thanks ------------------------------------------------------------------------------ This SF.Net email is sponsored by the Verizon Developer Community Take advantage of Verizon's best-in-class app development support A streamlined, 14 day to market process makes app distribution fast and easy Join now and get one step closer to millions of Verizon customers http://p.sf.net/sfu/verizon-dev2dev _______________________________________________ Owfs-developers mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/owfs-developers
