On 3 September 2016 at 13:04, Jan Kandziora <j...@gmx.de> wrote: > Am 03.09.2016 um 10:36 schrieb Colin Law: > ... > 2. You have to put > > dtoverlay=w1-gpio,gpiopin=4 > > or > > dtoverlay=w1-gpio-pullup,gpiopin=4,pullup=5 > > into your Raspberry Pi boot partition config.txt. And of course, the > w1-gpio resp. w1-gpio-pullup dtb files have to be present in the boot > partition overlays directory. Then reboot.
Could I ask for further clarification on this please? I have used dtoverlay=w1-gpio,gpiopin=4 and installed the kernel module using sudo modprobe w1-gpio and the DS18B20 works fine in three wire mode with a 4.7k pullup on DQ Google tells me (Ithink) that if I use dtoverlay=w1-gpio-pullup,gpiopin=4,pullup=5 then I can use parasitic mode with an external strong pullup driven by gpio05 in the way described in [1] However other results appear to suggest that I can use parasitic mode without the strong pullup, and I have also seen suggestions that to install the module I could use modprobe w1-gpio pullup=1 and I have been unable to determine exactly how the various options relate to each other. Further clarification would be much appreciated. Regards Colin [1] https://hatfors.wordpress.com/2015/09/12/measuring-temperature-with-a-parasite-power-1-wire-sensor-raspberry-pi-and-integrating-into-ose-using-haskell/ > > > 3. You have to use --w1 for this. The w1 kernel driver is the only way > to use the bitbanging host adapter. > > > 4. You have to update your owfs to 3.1p1 or later, because Debian Jessie > uses kernel 3.16.x, and there was a long-unseen incompatiblity between > post-3.16rc kernels and pre-3.1p1 owfs. > > You can use the owfs packages from the Raspbian testing repository. Edit > (or create) your /etc/apt/preferences to contain: > -------------------------------------------------------------------------- > Package: * > Pin: release o=Raspbian,a=stable > Pin-Priority: 500 > > Package: * > Pin: release o=Raspbian,a=testing > Pin-Priority: 300 > -------------------------------------------------------------------------- > This is important so you keep stable (Jessie) for all packages but the ones > explicitly taken from testing (Stretch). > > > Then, add a line > -------------------------------------------------------------------------- > deb http://mirrordirector.raspbian.org/raspbian/ testing main contrib > non-free rpi > -------------------------------------------------------------------------- > to your /etc/apt/sources.list to get access to the Raspbian testing > repository. > > Do an > > $ sudo apt-get update > > to read the package metadata, then check > > $ sudo apt-cache policy > > whether the testing repo is there with priority 300. Then > > $ sudo apt-get update -t testing owserver ow-shell > > That should install all you need, including the startup files and systemd > units. > Note you have to edit /etc/owfs.conf again to contain (this and only this) > -------------------------------------------------------------------------- > !server: server = localhost:4304 > server: w1 > -------------------------------------------------------------------------- > Restart the owserver service after that. > > > Done. > > > Kind regards > > Jan > > ------------------------------------------------------------------------------ > _______________________________________________ > Owfs-developers mailing list > Owfs-developers@lists.sourceforge.net > https://lists.sourceforge.net/lists/listinfo/owfs-developers ------------------------------------------------------------------------------ _______________________________________________ Owfs-developers mailing list Owfs-developers@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/owfs-developers
