Jerry Scharf wrote: >to keep the bus topology. Because I don't know how many will be 18b20s >connected, I am putting a dip switch that will allow the bus to bypass >open rj45s.
>This got me thinking about how long a stub I can have running from the >bus to the actual device. I know an inch on a board trace is fine, but >how long a stub can I get away with and still have the bus being happy? >I am wondering if the rj45 cable is 1-2 feet long, could I just leave >the switch shorted and plug the cable in? Every stub will cause reflections, so leaving the cable plugged in will not be good. If it matters in the end depends on a lot of (other) factors as well. >While I'm at it, do people put a pull up resistor on the end of their >buses? I haven't done so in the past but am wondering with a setup that >really can't fail. If so, what value should it be? I'd just solder a >resistor on the end of a stub of ethernet cable then shrink wrap it. If you can put a resistor there, then you should, to avoid the reflection at the end. The resistor should match the impedance of the cable used. -- Stephen. ------------------------------------------------------------------------------ New Year. New Location. New Benefits. New Data Center in Ashburn, VA. GigeNET is offering a free month of service with a new server in Ashburn. Choose from 2 high performing configs, both with 100TB of bandwidth. Higher redundancy.Lower latency.Increased capacity.Completely compliant. http://p.sf.net/sfu/gigenet _______________________________________________ Owfs-developers mailing list Owfs-developers@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/owfs-developers
