On Fri, Mar 26, 2010 at 3:21 AM, Alex Shepherd <list...@ajsystems.co.nz> wrote:
> Just joined the list, so - hello everyone! Welcome! > > Last year I've had some custom PCB's made (min order of 100 actually) for > the DS28EA00 sensor to use in my new house to monitor the floor/room > temperatures and control my underfloor heating system, that's powered by a The DS28EA00 is supported in OWFS for temperature and PIO. Chain mode hasn't been implemented, since there was no demand and since it fits a little awkwardly in our filesystem metaphor. > > Having a background in industrial automation and control system I thought > I'd try and be a bit smarter with the controls side of things and sprinkle a > bunch of sensors around the house to have a better idea of the thermal load > characteristics of the house and hopefully control it a bit better than with > just a simple thermostat on the wall. However I did run some mains cables to > where thermostats on the wall could go in case my grand plans fail... :( There is a DS1821 thermostat chip. It's only sort of a 1-wire device, with no ID and needing external circuitry to return to 1-wire control. You would be better off using a microprocessor 1-wire slave. > I have run 2 separate microLAN's using Cat5e UTP cable that will have about > 20-30 sensors on each LAN. These LAN's run back to my central comms rack. I > decided to keep the LAN's simple and linear as I need robustness and so I > avoided going down the path of hubs etc to manage what would become a star > network with it's associated impedance problems. Very nice. Even if your wire runs didn't return to the same location, you could have joined the 1-wire networks with owserver over TCP/IP. > I have 3 x LinkUSB adaptors (1 spare for a while) and an old Compaq Thin > Client with a 2.5" 80G disk and Debian LXDE Linux installed. I'll use this > initially to get things going and host a web server to display the various > room temperatures on a nice graphs to assist with commissioning the system. > Hopefully I will be able to move some or all of this to a diskless NSLU2 > once things are all working. The NSLU2 certainly works. Something more recent like the SheevaPlug is the same price and power consumption and has 512MB ram vs 32MB. > Initially I need to get my head around how to configure owfs to interface > the 2 LinkUSB adaptors and get the temperatures stored in a database > somewhere on my LAN and display the temperatures on graphs via a web > browser. Once I get the measurement system in place I'll move on to > controlling it. I'd use owserver as the interface to the LINK adapters, and then communicate with owserver using the various OWFS programs. This allows ad-hoc queries and debugging, while also running a data collection and control process separately. The general syntax is /opt/owfs/bin/owserver -d serial_port -p tcp_port (default tcp_port of 4304 is used if -p is omitted) Linking the two adapters is effortless, just list them both on the command line. /opt/owfs/bin/owserver --LINK /dev/ttyS0 --LINK /dev/ttyS1 (Here I used the LINKs in LINK mode rather than DS9097U emulation mode, and used the default port of 4304) Depending on serial port permissions, this may have to be run as root. To see your network: /opt/owfs/bin/owdir To mount it as a filesystem on /mnt/1wire (with proper permission) /opt/owfs/bin/owfs -s 4304 -m /mnt/1wire Then get all your temperatures with grep -r '.' /mnt/1wire/*/temperature You should also look at the alias file entry to give each of the sensor ID a human readable name (like the location of the sensor). As for making web interface, and storing in a database, I'll let other people chime in. Paul Alfille ------------------------------------------------------------------------------ Download Intel® Parallel Studio Eval Try the new software tools for yourself. Speed compiling, find bugs proactively, and fine-tune applications for parallel performance. See why Intel Parallel Studio got high marks during beta. http://p.sf.net/sfu/intel-sw-dev _______________________________________________ Owfs-developers mailing list Owfs-developers@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/owfs-developers
