-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA512 Jan,
Thanks for that, I'll implement the verification on write, I didn't realize that I could read from the output register without affecting state. This may be enough to get the levels of reliability I need. Note that the only element in the system that gets hot, or even warm for that matter, is the DS18B20. Heating of connectors isn't a problem. When I first discovered this issue I replaced all the wiring, connectors, and devices to make sure everything was well connected and working properly. The results were identical. The HobbyBoards I/O board is where I'm inserting power for the bus. It also grounds pins 1, 2, 5, and 8 on the RJ45. I could ground the rest, but it doesn't seem likely that this would cause a temperature sensitivity such as what I'm seeing even if it introduces some additional noise through capacitive coupling. I'm not doing anything programmatically with owcapi that would scan the bus other than at initialization when I read the directory. However, I don't know what owfs is doing in the background. The BAE0911 sounds interesting, but seems to be severe overkill for the purpose, especially if I want to commercialize any of this. It also doesn't seem to be available from distributors as a chip or board in the US, and I can't find anything on the RailBox Board availability anywhere. The only reference is the Brain4home.eu site which appears to be down. Regards, Paul Jan Kandziora wrote: > Am 29.04.2015 um 02:04 schrieb Paul W Panish: >> I’m providing power and ground through the CAT5e cabling. >> > I assume you use one wire for +5V, one wire for 1W and six wires for > GND? That would be correct. > > >> The errors are not just on access to the temperature sensors (which >> are hot), but also on access to the DS2408 devices (which remain at >> room temperature), though much less frequently. >> > If you don't scan the bus, all chips but the addressed one are > remaining in pure listen mode, so they could interfere with others > only by shorting the bus at random times. That's not very likely > unless you are near 125°C chip temperature. > > I'd say, check cabling and connectors, they may move mechanically > when heated. > > > >> I’ve implemented a redundant read mechanism (in addition to any >> redundancy owfs implements), which has made the system usable, but >> over the long term this is a risky solution. I can tolerate the >> read errors assuming I get an occasional success, however if a >> write to a PIO output is dropped the results could be messy. >> > The obvious solution is to read the PIO after writing and retry if > writing has failed. > > > I personally use Pascal's BAE0911 instead of DS2408 and have put a > simple AE watchdog program on it so it going into a safe default > automatically after some seconds without communication. > > Kind regards > > Jan > > ------------------------------------------------------------------------------ > > One dashboard for servers and applications across Physical-Virtual-Cloud > Widest out-of-the-box monitoring support with 50+ applications > Performance metrics, stats and reports that give you Actionable > Insights Deep dive visibility with transaction tracing using APM > Insight. http://ad.doubleclick.net/ddm/clk/290420510;117567292;y > _______________________________________________ Owfs-developers > mailing list Owfs-developers@lists.sourceforge.net > https://lists.sourceforge.net/lists/listinfo/owfs-developers -----BEGIN PGP SIGNATURE----- Version: GnuPG/MacGPG2 v2 Comment: GPGTools - https://gpgtools.org iQEcBAEBCgAGBQJVQQhjAAoJEG+gBufEaU3Y+SwIANK/JfdvRtWUFfPzf6ZMTwNB BlC0pSWSqBfhzLeIrffvrryvl+j52suLo50mNXEa+J1ujVKLKnP3oSVUbMJqFo62 V3yD39BLOC+SzX53qojfGq7TUF8rncQF1GklqApXvo5auyaKTqtGuXvagp10tosC 6YAVUkMiHu3lDhwWulbaJUiwzTaiYZo4UkBuIzfNWHjPidH7lJen/LY2CkaibSsR CDazWOJnpzitroacAnWJz2Ct3l2M1uuUWsEKGNN78/TEmAWf4agLH+DTIgijH5To GYMAUzxxZxw2nr7hUgAfpBAQT9b70we/l99nbwSTVG5J11eKU+JLji9x8F/cWaA= =0rF+ -----END PGP SIGNATURE----- ------------------------------------------------------------------------------ One dashboard for servers and applications across Physical-Virtual-Cloud Widest out-of-the-box monitoring support with 50+ applications Performance metrics, stats and reports that give you Actionable Insights Deep dive visibility with transaction tracing using APM Insight. http://ad.doubleclick.net/ddm/clk/290420510;117567292;y _______________________________________________ Owfs-developers mailing list Owfs-developers@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/owfs-developers
