On Wed, Jan 25, 2012 at 09:16:11AM -0800, Jerry Scharf wrote: > Mick, > > The problem with 1-wire is that it is has "single ended" data > communications signaling vs. "differential" in rs485 or ethernet over > cat5. If you have the differential on a single twisted pair, the signal > will be very resistant to external noise. With single ended systems, > noise is always a problem. The more wire and the worse the environment, > the greater the problem (think of it as a giant antenna.)
Nice post. Indeed, with the 1-wire (without power) mode and twisted pair and a single endpoint you are in effect getting differential signalling (with a dc bias). Once you add a second element to this, or provide power, this breaks down. Which is why star topologies are much more reliable for 1-wire. njh ------------------------------------------------------------------------------ Keep Your Developer Skills Current with LearnDevNow! The most comprehensive online learning library for Microsoft developers is just $99.99! Visual Studio, SharePoint, SQL - plus HTML5, CSS3, MVC3, Metro Style Apps, more. Free future releases when you subscribe now! http://p.sf.net/sfu/learndevnow-d2d _______________________________________________ Owfs-developers mailing list Owfs-developers@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/owfs-developers
